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1.
PURPOSE: Three patients with acute hepatitis B virus infection were identified who had been hospitalized on the same medical ward during a 19-day period several months earlier. An investigation was undertaken to determine if nosocomial transmission had occurred. SUBJECTS AND METHODS: A cohort study of patients admitted to the medical ward during the 19-day period in 1995 was conducted. In addition, we reviewed medical charts and laboratory records of all patients with acute hepatitis B virus infection who had been admitted to the hospital from 1992 through October 1996 to identify other cases with possible nosocomial acquisition. RESULTS: The 3 patients who had developed acute hepatitis B infection 2 to 5 months after hospitalization on the same medical ward had diabetes mellitus but no identified risk factors for hepatitis B infection. A source patient with diabetes mellitus and hepatitis B "e" antigenemia also was present on the same medical ward at the same time; all 4 patients were infected with the same viral subtype (adw2). Diabetes mellitus and fingerstick monitoring were associated with illness (P <0.001). Through the review of medical charts and laboratory records, 11 additional cases of suspected nosocomial acquisition via fingersticks were identified in 1996, including two clusters involving an unusual subtype of hepatitis B virus (adw4). The fingerstick device employed had a reusable base onto which disposable lancet caps were inserted. There was ample opportunity for cross-contamination among patients because deficiencies in infection control practices, particularly failure to change gloves between patients, were reported by nurses and patients with diabetes mellitus. CONCLUSION: Transmission during fingerstick procedures was the most likely cause of these cases of nosocomial hepatitis B infection. Contamination probably occurred when healthcare workers failed to change gloves between patients undergoing fingerstick monitoring, although other means of contamination cannot be ruled out.  相似文献   

2.
This study was designed to determine whether ambulatory electrocardiography in patients with recent stroke would lead to a change in clinical management or outcome and to express these findings in terms of cost benefit. A prospective, consecutive sample of patients (n = 100) with recent stroke referred from the neurology or medical services for ambulatory electrocardiography was identified. Ambulatory electrocardiograms were reviewed to identify patients with potentially important bradyarrhythmias, tachyarrhythmias, or atrial fibrillation. Patients were then followed up without interference with ongoing care to determine whether these findings led to changes in clinical management that might influence patient outcome. Of the 100 patients, 16 had an index "important" arrhythmia. No significant bradyarrhythmias were noted. Nonsustained ventricular tachycardia (> or = 6 complexes) in two patients and supraventricular tachycardia (> or = 10 complexes) in seven patients did not lead to management changes. Four patients had a history of atrial fibrillation who were in sinus rhythm; anticoagulation had been addressed in three; the fourth patient died before the issue could be addressed. Of three patients in atrial fibrillation, there was a history of atrial fibrillation and a decision regarding anticoagulation in each before monitoring. The cost of these 100 ambulatory electrocardiograms was about $55,000. In conclusion, these findings do not support the routine use of ambulatory electrocardiography in the evaluation of patients with stroke.  相似文献   

3.
BACKGROUND: The phantom breast syndrome (PBS) is a complication of mastectomy which consists of a sensation of breast persistence after mastectomy. MATERIALS, PATIENTS AND METHODS: The incidence, clinical course and location of PBS in 97 operated women were studied for a 15-year period. All women were interviewed in postoperative follow-up controls after mastectomy. RESULTS: The incidence of PBS was 29 patients out of the 97 total. The syndrome was present for more than 48 months in eleven of these patients. In most cases the location of "phantom sensations" was the nipple (15 cases) and the entire breast in five patients. In only three patients was phantom breast pain (PBP) reported whereas some discomfort was reported by the other patients. CONCLUSIONS: The incidence of PBS in our series was similar to that reported by other authors, but PBP was less common. Neither postoperative sequelae nor the antitumoral specific therapy seemed to have influence on the emergence of PBS.  相似文献   

4.
OBJECTIVES: This study sought to assess the maximal rate of acute Thrombolysis in Myocardial Infarction (TIMI) grade 3 patency that can be achieved in unselected patients. BACKGROUND: Early and complete (TIMI grade 3 flow) reperfusion is an important therapeutic goal during acute myocardial infarction. However, thrombolysis, although widely used, is often contraindicated or ineffective. The selective use of primary and rescue percutaneous transluminal coronary angioplasty (PTCA) may increase the number of patients receiving reperfusion therapy. METHODS: A cohort of 500 consecutive unselected patients with acute myocardial infarction were prospectively treated using a patency-oriented scheme: Thrombolysis-eligible patients received thrombolysis (n = 257) and underwent 90-min angiography to detect persistent occlusion for treatment with rescue PTCA. Emergency PTCA (n = 193) was attempted in patients with contraindications to thrombolysis, cardiogenic shock or uncertain diagnosis and in a subset of patients admitted under "ideal conditions." A small group of patients (n = 38) underwent acute angiography without PTCA. Conventional medical therapy was used in 12 patients with contraindications to both thrombolysis and PTCA. RESULTS: Ninety-eight percent of patients received reperfusion therapy (thrombolysis, PTCA or acute angiography), and angiographically proven early TIMI grade 3 patency was achieved in 78%. Among patients with TIMI grade 3 patency, thrombolysis alone was the strategy used in 37%, emergency PTCA in 40% and rescue PTCA after failed thrombolysis in 15%; spontaneous patency occurred in 8%. CONCLUSIONS: Reperfusion therapy can be provided to nearly every patient (98%) with acute myocardial infarction. Rescue and direct PTCA provided effective early reperfusion to patients in whom thrombolysis failed or was excluded.  相似文献   

5.
OBJECTIVE: To determine the value of visible retinal emboli as a diagnostic "test" for the detection of hemodynamically significant carotid artery stenosis in the setting of acute retinal artery occlusion. METHODS: A cross-sectional diagnostic accuracy study was performed in a tertiary North American center, with the results of the dichotomous diagnostic test (the presence or absence of visible retinal emboli) being placed against the dichotomous outcome of the presence or absence of hemodynamically significant carotid artery stenosis (defined as > or = 60%, or < 60%, carotid artery stenosis on either side). RESULTS: Forty-eight (18.7%) of our 256 patients had hemodynamically significant carotid artery stenosis. The sensitivity and specificity of retinal emboli for the detection of hemodynamically significant carotid artery stenosis were 39% and 68%, respectively. The presence of a visible retinal embolus generated a likelihood ratio of 1.24 (95% confidence interval, 0.84-1.86). This value corresponds to a patient with a pretest probability of 50% having a posttest probability of 55.3%. The absence of a visible retinal embolus generated a likelihood ratio of 0.88 (95% confidence interval, 0.68-1.15). CONCLUSIONS: The presence of a visible retinal embolus is a poor diagnostic test for the detection of hemodynamically significant carotid artery stenosis in the setting of acute retinal artery occlusion. Accordingly, the presence of an embolus should not influence the decision to perform carotid Doppler ultrasonography in patients with acute retinal arterial occlusion.  相似文献   

6.
The evaluation of risk after myocardial infarction accomplishes two objectives: a) selecting patients with high-risk for coronary angiography and revascularization, and b) identifying low-risk patients to avoid unnecessary laboratory investigation and revascularization procedures. Currently, patients eligible for exercise test are those with no evidence of heart failure or angina, and with a preserved left ventricular function. Overall prognosis for such patients, especially if they were thrombolyzed, is very good. In this setting, in contrast to that pointed out in previous reports, the positive predictive value of exercise electrocardiography is very low (i.e., a patient with S-T depression has a probability of cardiac death in the ensuing year of only 4% vs 2% if the test is negative). This suggests that a routine postinfarction exercise test is inefficient from a prognostic point of view. However, a recent study has shown that thrombolyzed patients with a positive response to the exercise test, have a significantly lower rate of reinfarction and unstable angina when they undergo myocardial revascularization. Mortality rate, as it was low in the study population, was unchanged by the use of revascularization procedures. We conclude that, in spite of the limitations pointed out, there are at least two reasons to continue performing exercise tests in all uncomplicated infarctions: a) a negative test, due to its high negative predictive value for adverse events, reassures the patient and his family and prompts an early discharge, and b) some patients, despite an uncomplicated in-hospital evolution, have a "strong" positive response that suggests multivessel disease and a possible benefit from myocardial revascularization.  相似文献   

7.
Student attrition at colleges across the United States poses a significant problem for students and families, higher educational institutions, and the nation's workforce competing in the global economy. Heavy drinking is a highly plausible contributor to the problem. However, there is little evidence that it is a reliable predictor of attrition. Notably, few studies take into account indicators of collegiate engagement that are associated with both heavy drinking and persistence in college. Event-history analysis was used to estimate the effect of heavy drinking on attrition among 3,290 undergraduates at a large midwestern university during a 4-year period, and student attendance at a number of college events was included as covariates. Results showed that heavy drinking did not predict attrition bivariately or after controlling for precollege predictors of academic success. However, after controlling for event attendance (an important indicator of collegiate engagement), heavy drinking was found to predict attrition. These findings underscore the importance of the college context in showing that heavy drinking does in fact predict attrition and in considering future intervention efforts to decrease attrition and also heavy drinking. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

8.
BACKGROUND: After myocardial infarction, African Americans have been reported to undergo fewer catheterization and revascularization procedures than whites, but few studies have addressed racial variations in the delivery of thrombolytic therapy. METHODS: We conducted a retrospective analysis of data prospectively collected on consecutive patients admitted with acute myocardial infarction to the 16-bed coronary care unit of a large, urban teaching hospital. RESULTS: Over a 5-year period, 1948 consecutive patients were admitted with acute myocardial infarction to a single coronary care unit. Thrombolysis was administered to 19% of 1024 African Americans and 29% of 924 whites (P <.01). The initial diagnostic impression on admission was "definite" infarction less often in African Americans (30%) than in whites (43%, P <.001), a difference that appeared to largely account for the difference in thrombolytic administration in a multivariable model. Mortality adjusted for age and concomitant illnesses was similar in African Americans compared with whites (relative risk 1.0, 95% confidence interval 0.78 to 1.51). CONCLUSIONS: Much of the racial variation in thrombolytic administration could be accounted for by differences in clinical presentation, an issue that requires further study.  相似文献   

9.
BACKGROUND AND PURPOSE: Whether an initial depression of function in the unaffected hemisphere ("transcallosal diaschisis") plays a role in early neurological recovery after acute stroke remains controversial. Previous studies were confounded by lack of acute-stage assessment with follow-up and by the problem of defining a suitable control group, since preexisting stroke risk factors may influence prestroke cerebral metabolism. We evaluated with positron emission tomography (PET) the relationships between unaffected-hemisphere (ie, contralateral) oxygen consumption (cCMRO2) and quantitative neurological assessments (and their respective evolution over time) after ischemic stroke. METHODS: Among 30 consecutive patients with first-ever middle cerebral artery ischemic stroke studied with the (15)O equilibrium method, we selected all survivors (n=19; mean age, 74.6 years) who were investigated both within the first 18 hours after stroke onset (PET1; mean, 11 +/- 4 hours) and 15 to 30 days later (PET2; mean, 24 +/- 10 days), with each patient serving as his/her own control. Neurological deficits were quantified using Orgogozo's middle cerebral artery scale (N score) at each PET session. Neurological changes were calculated as changes in the N score. A late CT scan coregistered with PET provided infarct topography and volume index. RESULTS: At PET2, we observed the overall expected neurological recovery. There was a nearly significant trend for a decrease in cCMRO2 from PET1 to PET2, especially for the neocortex (P=.08, F test); in a subgroup of eight patients with large infarcts, this CMRO2 decline was significant (P<.05) in the mirror region to the infarct. There was no significant correlation (Spearman's tests) between acute-stage cCMRO2 and same-day N scores or between changes in cCMRO2 versus changes in N score from PET1 to PET2 (any region). There was a nearly significant trend for lower PET2 cCMRO2 in the subgroup of eight patients with large compared with small infarcts (P=.06). CONCLUSIONS: We found no evidence for an influence of cCMRO2 on acute-stage neurological deficit or for a role of the unaffected hemisphere in early recovery after acute MCA ischemic stroke. The decline in unaffected-hemisphere metabolism from the acute to the subacute stage in the face of overall clinical recovery appears clinically irrelevant. The fact that the neocortical cCMRO2 at PET2 tended to be lower, and declined significantly from PET1 to PET2 in the mirror region in the subgroup of patients with large infarcts, suggests that this delayed effect represents transcallosal fiber degeneration.  相似文献   

10.
Rats that had been pretrained on 2 tests of allocentric memory (water maze and T maze) received bilateral cytotoxic lesions in the anterior thalamic nuclei (ATN) or transection of the fimbria-fornix (FF). After surgery, both groups of rats were impaired on both tasks, although the preoperative training resulted in a rapid initial reacquisition of the water maze task. Those rats with lesions largely restricted to the ATN were impaired at a level comparable to that produced by FF lesions. This finding is consistent with a close functional relationship between the hippocampus and the ATN, necessary for the acquisition and on-line processing of allocentric spatial information but not for the maintenance/retrieval of procedural information. The rats with more extensive thalamic lesions were more impaired in both tasks and did show a loss of procedural information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

11.
This article examines whether longitudinal reading trajectories vary by the generational status of immigrant children as they begin formal schooling through the 3rd grade. The results of the hierarchical linear model indicated that 1st and 2nd generation children (i.e., those born in a foreign country and those born in the United States to foreign-born parents, respectively) had higher achievement scores at the spring of kindergarten than did 3rd generation children. Yet, controlling for race/ethnicity and maternal education fully reduced the 1st generation advantage. In addition, 1st generation children grew in reading achievement at a faster rate than did 3rd generation children. Controlling for a host of proximal and distal factors that included demographic, race/ethnic, family, and school characteristics somewhat reduced the association between generational status and rate of growth. First and 2nd generation children continued to increase their reading scores at a faster rate than did 3rd generation children. It is likely that additional factors not measured in the Early Childhood Longitudinal Survey-Kindergarten cohort, such as selection, cultural, or motivational factors, would be useful in further explaining the immigrant advantage. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

12.
BACKGROUND: Conventional management of stage IV colorectal carcinoma is palliative. The value of resecting both liver and lung colorectal metastases that occur in isolation of other sites of metastasis is undetermined. OBJECTIVES: Our objectives were to (1) assess the efficacy of resecting both hepatic and pulmonary metastases, (2) investigate the influence of the sequence and timing of metastases, and (3) identify the profile of patients likely to benefit from both hepatic and pulmonary metastasectomy. Patients and methods: Of 48 patients identified with resection of colorectal cancer and, at some point in time, both liver and lung metastases, 25 patients underwent metastasectomy (resection group). The remaining 23 patients comprised the nonresection group. Risk factors for death were identified by multivariable analyses. RESULTS: Median survival was longer after the last metastatic appearance in the resection group (16 months) than in the nonresection group (6 months; P <.001). The pattern of risk also differed; it peaked at 2 years and then declined in the resection group but was constant in the nonresection group. In the resection group, patients with metachronous resections survived longer after colorectal resection (median, 70 months) than patients with synchronous (median, 22 months) or mixed resections (median, 31 months; P <.001). Risk factors for death included older age, multiple liver metastases, and a short disease-free interval. CONCLUSIONS: Younger patients with solitary metachronous metastases to the liver, then the lung, and long disease-free intervals are more likely to benefit from resection of both liver and lung metastases. Patients with risk factors also had better survival with resection than without resection.  相似文献   

13.
Difficulty monitoring and inhibiting impulsive behaviors has been reported in marijuana (MJ) smokers; neuroimaging studies, which examined frontal systems in chronic MJ smokers, have reported alterations during inhibitory tasks. Diffusion tensor imaging (DTI) provides a quantitative estimate of white matter integrity at the microstructural level. We applied DTI, clinical ratings, and impulsivity measures to explore the hypotheses that chronic, heavy MJ smokers would demonstrate alterations in white matter microstructure and a different association between white matter measures and impulsivity relative to nonsmoking control subjects (NS). Fractional anisotropy (FA), a measure of directional coherence, and trace, a measure of overall diffusivity, were calculated for 6 locations including bilateral frontal regions in 15 chronic MJ smokers and 15 NS. Subjects completed clinical rating scales, including the Barratt Impulsivity Scale (BIS). Analyses revealed significant reductions in left frontal FA in MJ smokers relative to NS and significantly higher levels of trace in the right genu. MJ smokers also had significantly higher BIS total and motor subscale scores relative to NS, which were positively correlated with left frontal FA values. Finally, age of onset of MJ use was positively correlated with frontal FA values and inversely related to trace. These data represent the first report of significant alterations in frontal white matter tracts associated with measures of impulsivity in chronic MJ smokers. Early MJ use may result in reduced FA and increased diffusivity, which may be associated with increased impulsivity, and ultimately contribute to the initiation of MJ use or the inability to discontinue use. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   

14.
15.
Using a historical approach of malaria control in the island of S?o Tomé, the author describes the evolution of strategies used with special reference to the last 25 years. From a zero mortality rate in children under 4 years in 1981/83, malaria became the first cause of morbidity and mortality after the epidemic of 1985/86. Malaria was introduced in 1493, when the virgin island was populated with individuals of various origins (Europe, Africa). The problem became more important as the population of S?o Tomé increased in the XIXth century, with immigration of workers for cultivation of coffee and cocoa. At that time, methods of control of "fevers" were already defined including drainage of swamps, cleansing of the environment and use of quinine for prophylaxis and treatment. At the beginning of the XXth century, with the first epidemiological investigations, global plans of medical assistance and free delivery of chloroquine were elaborated. Between 1946 and 1967, localities were stratified according to their endemicity, the major vectorial species (Anopheles gambiae sp.) were identified and the parasitological indices were calculated. All species of the malarial parasites coexisted, Plasmodium falciparum being the most prominent. In 1968, the Mission of Eradication of Malaria was created. Between 1977 and 1983, anti-vectorial control (indoor spraying, larvicides) resulted in a decrease of mortality rate. The interruption of the antivectorial control activities was responsible for the 1985/86 epidemic and the restoration of the levels of endemicity.  相似文献   

16.
An educational project in nursery schools was carried out with the aim to improve children's sleep. Its effectiveness was tested in terms of awareness of families and length of sleep of children. The method was a prevention trial based on the random division of classes of 3-year old into two groups (intervention group and control group) comprising children enrolled in nursery schools in the Rh?ne region (France) in 1992. The project, lasting 2 years, relied on physicians from the community (Maternal, Child Health Service and School Health Service), their role being to mobilise the teaching teams, distribute specific teaching tools and raise awareness of families to respect the sleep patterns of children, during routine medical examinations. The study was carried out in 140 nursery schools with 1,500 children in each group. The evaluation was based on the application of a logistical regression model taking potentially confounding factors into account, and an analysis in sub-groups in order to demonstrate the effectiveness of intervention on particularly exposed groups. The results show: 1) the feasibility of such an intervention among nursery school children on a large scale, 2) the effectiveness of the action, with a reduction of the risk of "poor knowledge" among parents (OR = 0.76), particularly in urban areas, and a reduction in the risk "short nights" in the sub-group of children who had " little sleep at 3 years" in low social class families (OR = 0.50).  相似文献   

17.
Infection of BALB/c mice with Trypanosoma cruzi resulted in up-regulated expression of Fas and Fas ligand (FasL) mRNA by splenic CD4+ T cells, activation-induced CD4+ T cell death (AICD), and in Fas: FasL-mediated cytotoxicity. When CD4+ T cells from infected mice were co-cultured with T. cruzi-infected macrophages, onset of AICD exacerbated parasite replication. CD4+ T cells from T. cruzi-infected FasL-deficient BALB gld/gld mice had no detectable AICD in vitro and their activation with anti-TCR did not exacerbate T. cruzi replication in macrophages. However, infection of BALB gld/gld mice with T. cruzi resulted in higher and more prolonged parasitemia, compared to wild-type mice. Secretion of Th2 cytokines IL-10 and IL-4 by CD4+ T cells from infected gld mice was markedly increased, compared to controls. In addition, in vivo injection of anti-IL-4 mAb, but not of an isotype control mAb, reduced parasitemia in both gld and wild-type mice. These results indicate that, besides controlling CD4+ T cell AICD and parasite replication in vitro, an intact Fas: FasL pathway also controls the host cytokine response to T. cruzi infection in vivo, being required to prevent an exacerbated Th2-type immune response to the parasite.  相似文献   

18.
Chemical and electronic synapses are present in the ocellar synaptic region of the moth, Trichoplusia ni. The chemical synapses all appear to be of "conventional" type. Four different chemical synaptic contacts were observed: Receptor cell axons presynaptic to receptor cell axons, receptor cell axons presynaptic to 1st order interneurons, 1st order interneurons presynaptic to receptor cell axons, and 1st order interneurons presynaptic to 1st order interneurons. Two different types of contact made by electronic synapes were observed: Contacts between receptor cell axons and 1st order interneurons, and contacts between 1st order interneurons. The significance of this synaptic arrangement for the generation of "on" and "off" responses in the 1st order interneurons is discussed.  相似文献   

19.
BACKGROUND: The syndrome angina pectoris with effort-related chest pain or discomfort is usually easy to recognize. However, vague and nonspecific symptoms may cause little reason for extensive evaluation. The prognosis of such patients in the general population has so far not been well described. HYPOTHESIS: The study was undertaken to investigate long-term prognosis in men with chest pain considered to be nonspecific in comparison with men with typical angina pectoris (AP) or prior myocardial infarction (MI), and men without chest pain. METHODS: At the second screening of the G?teborg Primary Prevention Study in 1974-1977, 6,488 men aged 51 to 59 years at baseline were available for the present analysis. Men who had responded positively to a postal questionnaire about chest pain during exercise or at rest were interviewed by a physician according to a Rose questionnaire at the screening examination. Those with typical or probable AP were further examined by single experienced physician. The following four groups were formed: Group 1: men who did not complain of chest pain (n = 5,545). Group 2: men who had not consulted any doctor because of chest pain, but who had chest pain according to a questionnaire (n = 441); these men were not considered to have AP according to a three-step examination by experienced physicians. Group 3: typical AP (n = 232). Group 4: men who had suffered an MI (n = 134). RESULTS: During 16 years of follow-up, coronary heart disease (CHD) mortality for Groups 1-4 was 8.0, 19.5, 24.8, and 48.5%, respectively. Mortality from all cardiovascular diseases was 11.5, 24.5, 31.2, and 59.0%, respectively. Noncardiovascular disease mortality was 14.1, 17.7, 14.3, and 8.7%, respectively. Thus, the relative risk (RR) for CHD mortality among men with nonspecific chest pain (Group 2) was 2.77 [95% confidence interval (CI) 2.20, 3.50], for all cardiovascular disease mortality 2.46 (95% CI 2.00, 3.02), and for noncardiovascular disease mortality 1.60 (95% CI 1.28, 2.00). Total mortality in this group was as high (44%) as among those with typical AP (45%), but the highest mortality was found among men with a previous MI (68%). In men without chest pain it was 26%. Patients of Groups 2-4 had higher levels of cardiovascular risk factors than those in Group 1. Neither any specific questions in the Rose questionnaire, nor electrocardiographic changes at rest (uncommon) were of prognostic significance. Serum cholesterol, systolic blood pressure, diabetes, and smoking were significant predictors of outcome, both with respect to fatal CHD and to total mortality during the 16-year follow-up. CONCLUSION: We found a high cardiovascular as well as noncardiovascular mortality among patients with chest pain who had not been considered to have AP at a three-step examination procedure. It is important to be suspicious of early CHD symptoms in men (and women?) with "nonspecific" chest symptoms and to analyze their cardiovascular risk factor pattern further because they are at considerably higher risk for future events than those in whom CHD is not suspected.  相似文献   

20.
This study examined whether social anxiety is diminished among women in the company of a group and, if so, whether it is associated with perceptions of anonymity, being distracted, feelings of security, or an expectation that any evaluation will be diffused across the members of the group. Two social scenarios were presented to 61 female undergraduate students: a physique-salient and a general social situation. For the former situation, self-presentational anxiety was less pronounced in a group of female friends and a mixed group of male and female friends than when alone or in a group of male friends. For the general social situation, in comparison with being alone, being in a group of female friends, being in a group of male friends, and being in a mixed group of male and female friends were associated with less social anxiety. Diffusion of evaluation and perceptions of security were most strongly associated with the reduction in social anxiety. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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