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1.
The epidemic cycle of Chlamydia pneumoniae infection was examined in two areas in eastern Finland over a period of 15 years, 1972-87. The C. pneumoniae IgG antibody prevalence was determined with 5-year intervals in a random sample of the population aged 25-59 years. The total number of sera studied using immunofluorescence was 2387. In 1972 the antibody prevalence was 57% and it increased to 66% in 1977. Over the next 5 years the prevalence decreased to 44% in 1982, but by 1987 it had again increased to 59%. The temporal variation in prevalence was statistically significant (P < 0.001) and similar for both genders. Throughout the observation period the overall prevalence was 7-11% higher in men than in women (P < 0.01). The antibody prevalence increased with age, being the highest among the oldest study subjects of both genders. The periods of high and low prevalence alternated in an epidemic cycle (P < 0.001) of about 10 years.  相似文献   

2.
Hospital discharge records were used to study the relationship between human immunodeficiency virus (HIV) epidemic and hospitalized patients with tuberculosis in New York State from 1987 through 1992. The discharges of patients coinfected with HIV and tuberculosis increased by 270%, rising from 1,573 in 1987 to 5,825 in 1992. This constitutes an increase from 19.8 to 49.1% of all discharges of patients with tuberculosis. Discharges of tuberculosis patients who were not infected with HIV decreased slightly during this time, going from 6,359 to 6,039. Postdischarge treatment plans, HIV prevention, HIV testing, and HIV educational programs for the tuberculosis population require special consideration, given the significant rise of HIV in the tuberculosis-infected population.  相似文献   

3.
Understanding storm-water runoff quality is required to develop effective urban storm-water runoff management for regions of semiarid climate. In this study, the quality of storm-water runoff from a semiarid, urban residential catchment, draining through separated storm-water sewers was investigated in 2006 and 2007. Water temperature, conductivity, pH, dissolved oxygen, and turbidity were continuously measured during 16 storm events. Storm-water runoff quality was characterized in terms of event mean values (EMVs), loads, and first flush (FF) loads and their relationships with rainfall characteristics. Discharge of total suspended solids (TSSs) is in general governed by the flow magnitude in storms and no significant relationships exist between the FF loads of TSS and rainfall intensity. The discharge of dissolved solids is independent of the flow magnitude. Strong FF effect for dissolved solids and weak FF effect for TSS were observed. This semiarid region provided no relationship between the EMVs of both TSS and conductivity and the antecedent dry period. This raises doubts on storm-water runoff being more heavily loaded with pollutants after a longer dry period in semiarid regions.  相似文献   

4.
This study examines the intermediate determinants of fertility in Sri Lanka by making use of the data collected in the 1982 Sri Lanka Contraceptive Prevalence Survey and the 1987 Sri Lanka Demographic and Health Survey. The analysis shows that the most important inhibitor of potential fertility is deliberate control. The marital structure of the population is also an important fertility-inhibitor, but lactational infecundability is increasingly becoming an unimportant contributor. The findings show the success of the family planning program in Sri Lanka, which propelled fertility to a substantial lower level. Achievement of the replacement level fertility by the turn of the century, set by the Sri Lankan government, would largely depend on the efforts to increase the quality and quantity of contraceptive use and the duration of breastfeeding.  相似文献   

5.
6.
The aim of this study was to determine whether gastric intramucosal pH (pHim) and/or gastric intramucosal carbon dioxide tension (PCO2,im) measured by tonometry can be used to predict the success of weaning in chronic obstructive pulmonary disease (COPD) patients. Twenty six consecutive COPD patients, undergoing mechanical ventilation for acute respiratory failure and satisfying the criteria of weaning from mechanical ventilation with nasogastric tonometer in place, were studied. Arterial blood gas values and PCO2,im were measured 24 h before (H-24), just before (H0), and after 20 min of a weaning trial on T-piece (H20min). Weaning failure was defined as the development of respiratory distress and/or arterial blood gas impairments during the first 2 h of spontaneous breathing on T-piece, or reintubation within 24 h after extubation. Between the weaning failure (n = 6) and weaning success (n = 20) groups, there were no differences in blood gas analysis readings at H-24 and H0 before the weaning period, age, Simplified Acute Physiology Score (SAPS) on admission, SAPS on the day of weaning trial, and duration of ventilation. Clinical status, tonometric and arterial gasometric data were similar at H-24 and H0 in all patients. During mechanical ventilation, pHim was < or = 7.30 in patients who failed weaning and > 7.30 in patients who were successfully weaned (p < 0.001; 100% sensitivity and specificity). The threshold value for PCO2,im of 8.0 kPa (60 mmHg) represents a clear demarcation with respect to outcome before the weaning trial. PCO2,im values during mechanical ventilation are significantly different (p < 0.001) between patients who were successfully weaned and those who were not (6.9 +/- 0.9 vs 9.9 +/- 1.1 kPa (51.9 +/- 6.7 vs 74.3 +/- 8.0 mmHg, respectively)). At H20min, pHim and PCO2,im were still statistically different between the weaning failure and the weaning success group. We conclude that measurement of gastric intramucosal pH (or gastric intramucosal carbon dioxide tension) represents a simple and accurate index to predict weaning outcome in chronic obstructive pulmonary disease patients before attempting weaning.  相似文献   

7.
The investigation done on the frequency or incidence of Paracoccidioidomycosis in the Republic of Paraguay, with the cases appeared and registered in the Institute of Pathology of Asuncion, presents an incidence rate of 0.46 per 100,000 in the total population; 0.52 per 100,000 in the population at risk. Considering the exposed masculine population the rate is 1.03 per 100,000 and for the feminine 0.02 per 100,000. The age group most affected is within the 50-54 year range with 3.54 per 100,000, the highest rate of all the groups studied. These are the incidence in a strongly exposed population which is controlled and well known. The period of 10 years (1960/69) which has been chosen for this investigation, shows a frequency of the mixed type (lymphatic-visceral or lymphoma-type) which reaches 25% of the total, and a low frequency for the pulmonary form which reaches a mere 12.5%. The mucocutaneous lesion with the involvement of the regional lymph nodes is the dominating form. Considering three consecutive 5 year periods between 1960 to 1974, no cases with proved pulmonary involvement were found until 1964; from 1965 to 1969 the percentage of pulmonary lesions in all the cases considered was 23.0% and from 1970 to 1974 reached to 38.4%. However, mucocutaneous and the lymphatic-visceral or mixed forms do not show significant variations. The rats are small and represent the incidence of this mycosis. It is suggested that a failure of the immunologic system would be found in those affected by the disease and there would be a strong resistence in the majority of the population exposed or within the endemic area of the infection.  相似文献   

8.
In this study, human platelets were used as a cellular model for exploring cytosolic free Ca (Cai) regulation in non-insulin-dependent diabetes mellitus (NIDDM). Cai levels were monitored in resting and thrombin-stimulated platelets from obese females with NIDDM; obese, nondiabetic women, and nonobese, nondiabetic women. All subjects were black. Significant and marked elevation of basal Cai levels was observed in platelets from the diabetic subjects when no aspirin was used during platelet isolation. However, no significant differences were observed in Cai between aspirin-treated platelets from women with NIDDM and platelets from nondiabetic women. The rate of the Cai return to basal level after thrombin stimulation was significantly lower in platelets from the diabetic subjects, suggesting an abnormality in platelet Ca extrusion or sequestration in NIDDM. Platelet Cai levels positively correlated with low-density lipoprotein cholesterol/high-density lipoprotein cholesterol ratio (LDL/HDL) and fasting blood glucose. These findings suggest abnormalities in platelet Cai homeostasis in NIDDM that are influenced by the serum lipid profile and perhaps glucose.  相似文献   

9.
BACKGROUND AND HYPOTHESIS: Valvar pulmonary stenosis is a common congenital heart defect. Progression of stenosis over time, even when mild initially, has been shown by serial cardiac catheterization studies in children and adults. We studied the natural history of asymptomatic valvar pulmonary stenosis diagnosed in infancy with two-dimensional echocardiography and Doppler method. METHODS: Between November 1986 and March 1993, 51 infants in the Northeast Tennessee and Southwest Virginia region were clinically diagnosed to have isolated valvar pulmonary stenosis. In 40 patients, the diagnosis was confirmed by two-dimensional echocardiogram/Doppler and color-flow mapping study at the time of presentation, and only their course is reported. Of 40 infants, six asymptomatic infants (15%) showed rapid progression of pulmonary stenosis over a relatively short period of time. Within the first 6 months of life, three of the six infants showed worsening of the stenosis needing intervention (one had surgical valvectomy and the others had percutaneous balloon valvuloplasty). The three other infants showed a more gradual increase of pulmonary stenosis over the first 2 years of life. RESULTS: Pulmonary stenosis even when mild can worsen in infancy, and it is not possible to predict which patients will follow this course. In our group of asymptomatic infants with initial mild pulmonary stenosis, 15% developed significant stenosis that needed intervention. CONCLUSION: We recommend frequent follow-up of asymptomatic infants with mild pulmonary stenosis during the first 2 years of life to detect rapid progression that may need intervention.  相似文献   

10.
11.
BACKGROUND: Hemochromatosis, which can lead to serious chronic diseases resulting from iron overload, has an estimated prevalence of 50 to 80 cases per 10000 persons. However, little population-based information is available on the impact of hemochromatosis on morbidity and mortality. OBJECTIVE: To evaluate trends over 14 years in deaths and medical conditions associated with hemochromatosis in the United States. DESIGN: We searched Multiple-Cause Mortality Files compiled by the National Center for Health Statistics for the years 1979 to 1992 for all records listing hemochromatosis. We used these data to calculate age-adjusted and age-specific mortality rates, identify medical conditions associated with a known diagnosis of hemochromatosis at death, and calculate proportionate mortality ratios for these medical conditions. RESULTS: The listing of hemochromatosis on death certificates increased 60% from 1979 to 1992. Decedents with hemochromatosis were 23, 13, and 5 times more likely to have liver neoplasms, liver disease, and cardiomyopathy, respectively, than were decedents without hemochromatosis. Conversely, decedents with liver neoplasms, liver disease, and cardiomyopathy were 26, 14, and 5 times more likely, respectively, to have hemochromatosis than were decedents without these conditions. Hemochromatosis was 82 times more likely in persons with the combination of liver neoplasms and diabetes and 43 times more likely in those with the combination of liver disease and diabetes than in those without these conditions. CONCLUSIONS: Comparison of the reported prevalence of hemochromatosis among decedents with estimates of prevalence in the general U.S. population suggests that either the penetrance or the recognition of hemochromatosis, or both, is low. Nevertheless, substantial mortality resulting from liver disease, liver neoplasms, cardiomyopathy, and a combination of liver disease and diabetes in patients with hemochromatosis argues for the improved diagnosis and treatment of hemochromatosis in persons with these conditions.  相似文献   

12.
This paper investigates the association between various psychiatric disorders and violent behavior using data from a community-based epidemiological study of young adults in Israel (N = 2678). Self-reports of recent fighting and weapon use were elevated among respondents diagnosed with psychotic or bipolar disorders but not among those diagnosed with non-psychotic depression, generalized anxiety disorder or phobias compared to respondents without these disorders. Violence was measured using the Psychiatric Epidemiology Research Interview; psychiatric disorders were diagnosed using a modified version of the Schedule for Affective Disorders and Schizophrenia. The analyses controlled for lifetime substance abuse, antisocial personality disorder and demographic characteristics, thereby extending support for a causal connection between some types of psychiatric disorders and violence. The association between disorder and violence was stronger among respondents with less education, indicating the potentially important role of social and cultural contexts in moderating the association between mental illness and violence.  相似文献   

13.
Resistance to toxicants is a convenient model for investigating whether adaptive changes are associated with pleiotropic fitness costs. Despite the voluminous literature devoted to this subject, intraspecific comparisons among toxicant resistance genes are rare. We report here results on the pleiotropic effect on adult survival of Culex pipiens mutants involved in the same adaptation: the resistance to organophosphorus insecticides. This field study was performed in southern France where four resistance genes sequentially appeared and increased in frequency in response to intense insecticide control. By repeated sampling of overwintering females through winter, we analysed the impact of each of three resistance genes on adult survival. We showed that (i) the most recent gene seems to be of no disadvantage during winter, (ii) the oldest affects survival in some environmental conditions, and (iii) the third induces a constant, severe and dominant survival cost. Such variability is discussed in relation to the physiological changes involved in resistance.  相似文献   

14.
The flow cytofluorimetric method allowed to show that intact liver nucleus population of adult (6 months) rats consists of discrete ploidy classes (2c, 4c, 8c and 16c+), from which the diploid class was approximately a half of the total nuclei. Thirty days after the wholebody X-ray irradiation with a dose of 2 Gy, the percentage frequency of each nuclear class was statistically unchanged. However, the polyploidization level of the total nuclear population increased. Partial hepatectomy induces an entering into mitotic cycle (maximum S-phase; 22 h after operation) of the most of the hepatocyte nuclei in both irradiated and unirradiated animals. With that the relative number of nuclei in S-phase decreases in geometric progression according to increasing of ploidy class. In regenerating liver of irradiated rats in comparison with that of unirradiated ones, the greater part of nuclei enters into the mitotic cycle at the expense of di- and especially tetraploid nuclei.  相似文献   

15.
Cellular elements of the vascular wall, such as endothelium (En) and smooth muscle cells/pericytes (SM/P) possess important immunologic properties. We have previously reported that murine brain microvessel En cells and SM/P express Major Histocompatibility (MHC) class II molecules and activate syngeneic CD4+ T cells in a class II dependent way. Herein we compare MHC class II expression on brain microvessel En to aorta large vessel En cells in order to explore the mechanisms of immune responses in brain tissue versus other peripheral tissues. Interestingly, we demonstrate that En cells from brain microvessel and large aortic vessel express the I-A but not the I-E subunit of MHC class II molecules. The expression of I-A class II molecules can be upregulated on brain microvessel and aortic En cells by interferon-gamma (IFN-gamma). Similarly, the expression of I-A, but not I-E, MHC class II molecules on brain microvessel endothelial cells was upregulated in the presence of activated T cells. Interleukin-10 (IL-10) was found to inhibit IFN-gamma-mediated upregulation of I-A class II molecule expression on aortic but not on microvessel En cells. Our data may indicate that some differences in organ-specific immune responses, are defined by local parameters, such as MHC distribution and regulation.  相似文献   

16.
Behavioral, neuropsychological, and brain imaging research points to a dedicated system for processing number that is shared across development and across species. This foundational Approximate Number System (ANS) operates over multiple modalities, forming representations of the number of objects, sounds, or events in a scene. This system is imprecise and hence differs from exact counting. Evidence suggests that the resolution of the ANS, as specified by a Weber fraction, increases with age such that adults can discriminate numerosities that infants cannot. However, the Weber fraction has yet to be determined for participants of any age between 9 months and adulthood, leaving its developmental trajectory unclear. Here we identify the Weber fraction of the ANS in 3-, 4-, 5-, and 6-year-old children and in adults. We show that the resolution of this system continues to increase throughout childhood, with adultlike levels of acuity attained surprisingly late in development. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

17.
BACKGROUND: Recently there has been increased interest in the special mental health needs of women. We used data from the PRIME-MD 1000 study to assess gender differences in the frequency of mental disorders in primary care settings, and to explore the potential impact of these differences on health-related quality of life (HRQL). SUBJECTS AND METHODS: One thousand primary care patients (559 women) were interviewed during the PRIME-MD study, which was conducted at four primary care clinics affiliated with university hospitals throughout the eastern United States. Patients completed a one-page questionnaire in the waiting room prior to being seen by the physician; patients and physicians then completed together a clinician evaluation guide that used DSM-III-R algorithms to diagnose mood, anxiety, somatoform, eating, and alcohol related disorders. Health-related quality of life was assessed with the Medical Outcomes Study SF-20 General Health Survey. RESULTS: Women were more likely than men to have at least one mental disorder (43% versus 33%, P < 0.05). Higher rates were particularly prominent for mood disorders (31% of women versus 19% of men, odds ratio [OR] = 1.9, 95% confidence interval [CI] 1.4 to 2.6), anxiety disorders (22% versus 13%, OR = 1.9, CI = 1.3 to 2.8), and somatoform disorders (18% versus 9%, OR = 2.2, CI = 1.5 to 3.4). Psychiatric comorbidity was also more common in women (26% of women had two or more mental disorders versus 15% of men, P < 0.05). Unadjusted HRQL scores, ranging from 0 to 100, with 100 = best health, were all significantly lower in women than in men (eg, physical function = 67 in women versus 76 in men, P < 0.0001; mental health = 69 in women versus 76 in men, P < 0.0001). Many HRQL differences persisted after controlling for age, education, ethnicity, marital status, and number of physical disorders; however, differences in HRQL were eliminated in 5 of 6 domains after controlling for number of mental disorders. When compared with female patients of male physicians, female patients of female physicians demonstrated similar satisfaction with care, health care utilization, HRQL, and recognition rate of mental disorders. CONCLUSIONS: In the 1,000 patients of the PRIME-MD study, mood, anxiety, and somatoform disorders and psychiatric comorbidity were all significantly more common in women than men. The HRQL scores were poorer in women than men, although most of this difference was accounted for by the difference in prevalence of mental disorders. These data suggest that one of the most important aspects of a primary care physician's care of female patients is to screen for and treat common mental disorders.  相似文献   

18.
A nested polymerase chain reaction (PCR) assay was used to determine the levels of cytomegalovirus (CMV) genomes in cells of CSF from 19 patients with AIDS and 12 human immunodeficiency virus type I (HIV-1) seronegative individuals with various neurologic disorders. Five AIDS patients had autopsy-proven CMV encephalitis (CMVE) and 14 patients had no evidence of CMV-related CNS manifestations. CSF cells from AIDS patients with confirmed CMVE harbored viral genomes at a median value of 3,333/10(5) cells (range, 1,667 to 5,333/10(5) cells; mean, 3,558/10(5) cells) compared with a median value of 125/10(5) cells (range, 9 to 1,000/10(5) cells; mean, 281/10(5) cells) for AIDS patients with CMV-unrelated symptoms and a median value of 1.9/10(5) cells (range, 0 to 562/10(5) cells; mean, 52/10(5) cells) for HIV-1 seronegative control subjects. A subset of CSF samples was assessed using a modified single round amplification PCR with a detection limit of 500 viral copies. CMV DNA was detected in all four specimens from AIDS patients with proven CMVE, in two of five AIDS patients without CMVE, and in none of five seronegative control subjects. Quantitation of CMV genomes in CSF cells is indicative of latent or productive CMV infection and is a reliable means for diagnosis of CMVE in patients with AIDS. Detection of a cutoff value of cellular CMV genomes by means of nonquantitative PCR may identify patients at risk for CMV infection of the CNS.  相似文献   

19.
This study demonstrated that, in rice seedlings, genotypic difference in tolerance to anoxia only occurred when anoxia was imposed at imbibition, but not at 3 d after imbibition. When seeds were imbibed and grown in anoxia, IR22 (anoxia-'intolerant') grew much slower and had lower soluble sugar concentrations in coleoptiles and seeds than Amaroo (anoxia-'tolerant'), while Calrose was intermediate. After 3 d in anoxia, the sugar concentrations in embryos and endosperms of anoxic seedlings were nearly 4-fold lower in IR22 than in Amaroo. Sugar deficit in the embryo of IR22 is presumably due to the limitation of sugar mobilization rather than the capacity of transport as shown by similar sugar accumulation ratios of 1.8 between embryo and endosperm in IR22 and Amaroo at 3 d in anoxia. With 20 mol m-3 exogenous glucose, coleoptile extension and fresh weight increments in anoxic seedlings of IR22 were much closer to those in the two other genotypes, nevertheless protein concentration remained lowest on a fresh weight basis in the coleoptiles of IR22; indicating that protein synthesis has a lower priority for energy apportionment during anoxia than processes crucial to coleoptile extension. In contrast to these responses to anoxia imposed at imbibition, IR22 had nearly the same high tolerance to anoxia as Calrose and Amaroo, when anoxia was imposed on seedlings subsequent to 48 h aeration followed by 16 h hypoxic pretreatment. In fact, coleoptiles of anoxic IR22 had higher sugar concentrations and grew faster than Calrose, and exogenous glucose had no effect on the coleoptile extension of IR22. Excised coleoptile tips of IR22 and Amaroo with exogenous glucose had similar rates of ethanol production and were equally tolerant to anoxia. In conclusion, much of the anoxia 'intolerance' of IR22 when germinated in anoxia could be attributed to limited substrate availability to the embryo and coleoptile, presumably due to slow starch hydrolysis in the endosperm.  相似文献   

20.
The authors examined the amount and durability of change in the cognitive content of 156 adult outpatients with recurrent major depressive disorder after treatment with cognitive therapy. The pre-post magnitude of change was large for the Attributional Style Questionnaire Failure composite (d = 0.79), Dysfunctional Attitudes Scale (d = 1.05), and Self-Efficacy Scale (d = 0.83), and small for the Attributional Style Questionnaire Success composite (d = 0.30). Changes in cognitive content were clinically significant, as defined by their 64%-87% scores overlapping with score distributions from community dwellers. Improvement was durable over a 2-year follow-up. Changes in negative cognitive content could be detected early and distinguished responders from nonresponders. In responders, continuation-phase cognitive therapy was associated with further improvements on only 1 measure of cognitive content. Early changes in negative cognitive content did not predict later changes in depressive symptoms, which the authors discuss in the context of methodological challenges and the cognitive theory of depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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