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991.
PURPOSE: To screen patients with abdominal aortic aneurysm for popliteal aneurysm and investigate cardiovascular and genetic risk factors associated with aneurysmal disease at more than one site (generalised aneurysmal disease). SUBJECTS, DESIGN AND SETTING: All patients referred to the Regional Vascular Surgical Service at Charing Cross Hospital with unruptured abdominal aortic aneurysm between 1989 and 1993 were screened for popliteal aneurysms, using ultrasonography. MAIN OUTCOME MEASURES: Palpation of a popliteal aneurysm or ultrasonographic detection of popliteal dilatation, where the ratio maximum popliteal fossa diameter/suprageniculate popliteal diameter was > or = 1.5, in relation to cardiovascular and genetic risk factors. RESULTS: Clinical examination detected popliteal aneurysms in only 11/232 patients (5%), but ultrasonography demonstrated the presence of popliteal aneurysm in a further 13 patients, 24/232 in total (10%). Multivariate regression identified four independent factors associated with popliteal dilatation disease: age (p = 0.046), height (p = 0.006), systolic hypertension (p = 0.037) and triglyceride concentration (p = 0.009). Generalised aneurysmal disease and systolic blood pressure were associated with polymorphic variation in the fibrillin-1 gene, but not with variations in the apolipoprotein B and type III collagen genes. CONCLUSIONS: Few patients with abdominal aortic aneurysm (10%) also have popliteal aneurysms: the risk of popliteal dilatation increases with age, height, systolic blood pressure, triglyceride concentration and fibrillin genotype. The strong interaction between fibrillin genotype and blood pressure may contribute to the familial tendency to aortic aneurysm.  相似文献   
992.
993.
To determine the suitability of a new colostrum substitute derived from goat serum and to determine the amount of colostral IgG needed to achieve serum IgG concentration > 800 mg/dl, twin kids from 14 does were fed colostrum or a colostrum substitute. The volume of colostrum or colostrum substitute fed was calculated so that half the kids in each group received IgG at a low dosage (1.5 g/kg of body weight) and the other half received IgG at a high dosage (3 g/kg). Kids were bottle fed the colostrum or colostrum substitute and then fed pooled goat's milk until 18 hours old, at which time they were allowed to nurse their dams. Does were milked manually every 2 hours after parturition until specific gravity of mammary secretions was < 1.02, the specific gravity of goat's milk. Serum IgG concentration of each kid was determined by means of single radial immunodiffusion at birth and 12, 18, and 24 hours and 7, 21, and 42 days after birth. Kids were weighed at each blood collection and monitored for illness daily. None of the kids had measurable serum IgG concentrations at birth. Mean serum IgG concentration was significantly higher in kids fed colostrum than in kids fed colostrum substitute at all times, except days 7 and 42 (P < 0.05). By 24 hours after birth, serum IgG concentration was > 800 mg/dl in all kids fed colostrum, in 4 of 7 kids fed the substitute at the higher dosage, and in 2 of 7 kids fed the substitute at the lower dosage.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
994.
Nine cases of unilateral internal derangement of TMJ indicated for surgical intervention, were selected for this study. The affected joints were imaged by MRI presurgically. The non-affected joints were also imaged as controls. MRI findings were correlated with intraoperative surgical findings. The results were absolutely accurate as regards degenerative joint pathosis and capsular rupture, and with high degree of accuracy (85.7%) in detection of disc displacement. Two cases of disc perforation were not detected by MRI. The results were promising and encouraging the use of this noninvasive imaging technique as presurgical aid in TMJ disorders.  相似文献   
995.
996.
The relation of exercise habits of 113 female college students to their knowledge about osteoporosis and their health beliefs was investigated, using the health belief model to determine why some people participate in self-care preventive actions but others do not. Age was positively correlated with the level of osteoporosis knowledge, awareness of personal susceptibility, and motivation for general health behaviors. Older participants, however, perceived more barriers to exercise as an osteoporosis-prevention measure than did the younger respondents. The authors' conclusions support the importance of early osteoporosis education and lifetime physical activities to prevent osteoporosis.  相似文献   
997.
In tasks requiring sustained attention, human alertness varies on a minute time scale. This can have serious consequences in occupations ranging from air traffic control to monitoring of nuclear power plants. Changes in the electroencephalographic (EEG) power spectrum accompany these fluctuations in the level of alertness, as assessed by measuring simultaneous changes in EEG and performance on an auditory monitoring task. By combining power spectrum estimation, principal component analysis and artificial neural networks, we show that continuous, accurate, noninvasive, and near real-time estimation of an operator's global level of alertness is feasible using EEG measures recorded from as few as two central scalp sites. This demonstration could lead to a practical system for noninvasive monitoring of the cognitive state of human operators in attention-critical settings.  相似文献   
998.
We evaluated the effects of 5-fluorouracil (5FU) and leucovorin (LV) on thymidylate synthase (TS) in normal rapidly dividing tissues, which may contribute to toxic side-effects of treatment with 5FU and LV. TS levels were determined in biopsies of human liver and colon mucosa and murine bone marrow, liver and intestinal mucosa at several time points after administration of therapeutic doses of 5FU or LV/5FU. In murine liver, after treatment with 100 mg/kg 5FU, TS inhibition was significantly higher than after LV/5FU administration (P < 0.001). A similar trend was observed in human liver tissue. Murine intestinal mucosa had TS levels below the limit of detection after 5FU or LV/5FU treatment. In human colon mucosa samples, administration of 500 mg/m2 5FU resulted in a large extent of TS inhibition but the small number of samples did not allow a time- or 5FU-LV/5FU-related evaluation. TS activity in murine bone marrow cells was strongly inhibited to 10% of the control value during 48 h. LV/5FU administration resulted in a slightly higher inhibition. No human bone marrow was available to measure TS levels. Both in mice and humans the most pronounced TS inhibition occurred in the tissue that was involved in dose-limiting toxicity. Therefore it is very likely that TS inhibition in normal tissues contributes to the toxic side-effects of 5FU treatment.  相似文献   
999.
PURPOSE: Patients with relapsed acute myelogenous leukemia (AML), who are not eligible for bone marrow transplantation, have a poor prognosis when treated with chemotherapy alone. Total body irradiation (TBI) is an effective modality against AML when used in doses of 1000-1400 cGy with hematopoietic stem cell support. We undertook a phase I study of TBI with granulocyte-colony-stimulating factor (G-CSF) support, without stem cell support in patients with AML either in relapse or second or subsequent remission. METHODS AND MATERIALS: Patients with relapsed AML, or AML in second or subsequent remission were treated in a phase I study of TBI followed by G-CSF. The first dose level was 200 cGy. After the initial cohort of patients it was clear that patients with overt leukemia did not benefit from this treatment, and subsequent patients were required to be in remission at the time of TBI. RESULTS: Eleven patients were treated, 4 in overt relapse, and 7 in remission. 200 cGy was used in all, and dose escalation was not possible due to prolonged thrombocytopenia in all patients but one. Neutrophil recovery was adequate in those patients who remained in remission after TBI. Patients with overt leukemia had transient reduction in blast counts, but rapid recurrence of their leukemia. Patients treated in remission had short remissions, with the exception of one patient who is in remission 32 months after treatment. CONCLUSION: There is some antileukemic effect of TBI even at 200 cGy, though this dose appears to be too low to help a significant number of patients. If TBI is to be escalated without stem cell support, then a thrombopoietic agent will need to be used.  相似文献   
1000.
The purpose of this study was: (i) to examine the impact of the clinical severity, anatomical location and treatment of psoriasis on patients' quality of life, and (ii) to investigate the effects of perceptions of psoriasis-related stress on patients' physical and mental health and on areas of disability in everyday life. All patients (n = 204) attending a psoriasis specialty clinic were invited to complete a multidimensional quality of life assessment comprising the Psoriasis Disability Index (PDI), the SF-36 Health Survey and the Psoriasis Life Stress Inventory (PLSI). Results (n = 150) indicated that overall clinical severity of psoriasis as assessed by the Psoriasis Area and Severity Index, and duration of psoriasis, were unrelated to impairment in any areas of quality of life. Anatomical location (social visibility) of psoriasis was associated with self-report of poor physical health (P = 0.01), and there was a modest association with patients' mental health (P = 0.04); however, anatomical location of psoriasis was not significantly associated with self-reported disability in everyday life, or stress scores. Patients who were classified as more reactive to the stress associated with psoriasis (78% of the sample) were functioning less well in terms of their mental health (P = 0.001) and also experienced significantly more disability in all areas of everyday life (P = 0.001). Differences in method of treatment for psoriasis did not significantly affect scores on the psoriasis-specific (PDI; PLSI) or generic (SF-36) quality of life measures. A multiple regression analysis demonstrated that stress resulting from anticipating other people's reactions to their psoriasis contributed more to the variance in patients' disability in everyday life than any other medical or health status variable. The results support the importance of assessing the effects of stress in patients' adjustment to their condition and may indicate a role for adjunctive psychological stress management training for a significant number of patients with psoriasis.  相似文献   
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