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991.
The present studies measured bleeding times, without venous occlusion, in a series of patients, whose bleeding times (+ venostasis) consistently exceeded 20 min. During these tests, the amount of blood loss (expressed as mg/min) was also quantitated. To allow comparison, normal controls were studied before and following aspirin ingestion. In normal controls, the mean standard Ivy bleeding time was 5.0 with a range of 2.5 to 7.5 min. Two hours after aspirin (650 mg), this increased to 7.3 min (range 4.0-12.0). For comparison, the non-occlusive bleeding time averaged 3.8 min (1.0-6.5) and after aspirin 5.3 min (2.5-11.5). The measured amount of blood loss was 5.0 mg/min (0-10.5 mg/min) under all of the above conditions. At the other extreme, patients with severe bone marrow failure had occluded and non-occluded bleeding times in excess of 20 min. Moreover, these were often associated with excess blood loss. By contrast, patients with "Ivy" values greater than 20 min in association with platelet counts greater than 10,000/microliters had unpredictable bleeding parameters. In the latter group, the non-occluded values ranged from 1 to greater than 20 min. Of particular note, the non-occlusive times appeared to correlate with spontaneous bleeding manifestations. Only a rare patient (1/37), whose non-occluded value was less than 20 min, had worrisome bleeding. By contrast, serious bleeding manifestations were observed in 39% whose non-occluded value exceeded 20 min. This was even higher (64%) in those with a non-occluded value greater than 20 min and excess blood loss.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
992.
993.
We report the prevalence rates for dementia and Alzheimer's disease (AD) obtained from a probability sample survey of 5,055 noninstitutionalized older persons in Shanghai, China. A two-stage procedure was used for case finding and case identification. A Chinese version of the Mini-Mental State Examination was used to determine cases of possible dementia. Three different cutoff points on this mental status test were used depending on the respondent's level of education. Clinical evaluations, based on functional assessments and psychiatric interview, medical and neurological examinations, three standardized mental status tests, and a selected group of psychometric tests, were made in the second stage of the study to ascertain the clinical diagnosis of dementia and AD utilizing the Diagnostic and Statistical Manual for Mental Disorders, edition 3 and National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association criteria, respectively. The prevalence rate of dementia in persons 65 years and older was 4.6%. Clinically diagnosed AD accounted for 65% of the subjects with dementia. These findings indicate that the prevalence of dementia in Shanghai is very much higher than figures published earlier for China and Japan, and at the lower part of the range of values reported for community residents in the United States and other Western countries, but less than half of that reported in the recently published survey of the elderly in East Boston. Increasing age, gender (female), and low education are each highly significant and independent risk factors for dementia. One hypothesis to explain the increased prevalence in elderly women who had received no formal education invokes the possibility of an effect of early deprivation, perhaps lowering brain "reserve," allowing the symptoms of dementia to appear at an earlier date during disease progression.  相似文献   
994.
Bill 7, the most recent amendment to the Ontario Mental Health Act was introduced in December 1986. It has resulted in some major changes to the practice of psychiatry, especially in provincial hospitals. We compared patients who had discharged themselves against medical advice (AMA) during the six months before the Bill was enacted, with those who discharged themselves AMA in the 12 months following. Significantly more patients discharged themselves AMA in the post- than the pre-Bill period. The majority of these were potentially treatable, acutely ill individuals with schizophrenia or affective disorder. We argue that Bill 7 has largely failed in its objective to improve the overall "quality of care" to psychiatric patients, at least in the short term.  相似文献   
995.
Summary The authors compared the results of a retrospective analysis of two groups of head-injured patients who had coexistent pelvic or lower extremit fractures. One group was treated with early osteosynthesis within the first 12 hours after trauma, simultaneously with neurosurgical treatment, while the second group was treated neurosurgically and osteosynthesis was postponed for 4 to 10 days. The second group revealed a higher mortality, which was due to fat embolism. We conclude that early osteosynthesis is the treatment of choice in patients with coexistent head injury and lower extremity fractures.  相似文献   
996.
Two different results have been published in regard to the superoxide-stimulating activity of lipopolysaccharide or Lipid A in neutrophils: first, a direct stimulation after a lag time of about 30-60 sec and second, the inactivity of Lipid A if applied alone, being able only to "prime" the cells for a second challenge during a longer incubation period. In order to achieve clarity regarding these two different opinions, we asked the questions whether: (a) Lipid A is able to stimulate PMN directly, i.e. without a preincubation and a second stimulus; (b) fMLP and Lipid A show a synergistic effect; (c) a preincubation ("priming") of the PMN with Lipid A really increases the superoxide output after a second challenge. We observed (a) a direct stimulation of the chemiluminescence with Lipid A without an additional second challenge, accompanied by a seemingly unimodal kinetics of the superoxide output, i.e. mainly the second phase of the usually bimodal kinetics has been stimulated. As for question (b), a clearly detectable synergism between Lipid A and fMLP could be measured. Regarding question (c), a preincubation ("priming") with Lipid A was of no beneficial effect; the chemiluminescence count could be equally well increased without a "priming" compound.  相似文献   
997.
The surgical treatment of predominantly venous defects   总被引:1,自引:0,他引:1  
The predominantly venous defects consist of the truncular forms, as there is aplasia or obstruction in the truncular dilatation; and they consist of the extratruncular forms as there are the infiltrating ones and the limited ones, according to the Hamburg classification. The web or membranous obstruction of the inferior vena cava (IVC), dilatation or aneurysm of the jugular vein, infiltrating "cavernous angioma" and localized venous defects are the main lesions of those classifications reported in this communication. Jugular dilatation and localized extratruncular lesions have had good therapeutic results. Webs of the IVC can be treated by membranectomy, either by finger, transcardially, or balloon, percutaneously, and cavo- or mesoatrial shunt; however, membranectomy, along with cavoplasty as a radical treatment for such an entity, is advocated by the authors. The infiltrating extratruncular form is the unsolved important issue concerning its thorough resection. Skin graft taken from a resected tissue mass through a reversal split thickness skin graft by a drum type dermatome, removal of the lesion along with muscle layer(s), and staged operations are recommended.  相似文献   
998.
999.
Clinical-cytogenetic correlations were assessed in 79 patients with transitional cell carcinomas of the bladder to whom cytogenetic analysis of the primary tumor had been successful. High-grade (G2+G3) and high-stage (T2-T4) tumors had in general a higher ploidy level and contained more marker chromosomes, including multiple markers, compared to low-grade (G0+G1) and low stage (Ta+T1) tumors. The early recurrence rate (within 7 months) was significantly higher (p<0.05) in patients whose tumors contained marker chromosomes compared to cases without markers. Also, a significantly higher proportion of patients with marker chromosomes died due to their disease during the study period (follow-up time 30 months) compared to those without markers (84% versus 16%, p<0.005). The results confirm and extend previous studies showing that cytogenetic findings may be an important prognostic indicator in bladder cancer patients.  相似文献   
1000.
We have compared the specific activities of Cu/Zn superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) in a vinblastine sensitive human T-lymphoblastic cell line (CCRF-CEM) and its multiple drug resistant (MDR) counterpart cell line (CEM/VLB100), which over-expresses P-glycoprotein (PGP). We have found that the specific activity Cu/Zn SOD was consistently 38% increased in CEM/VLB100 cells compared with CCRF-CEM cells. In contrast, the activities of CAT and GSH-Px were similar in the two cell lines. These results suggest that MDR in CEM/VLB100 is a complicated phenotype which not only involves a PGP mechanism, but also a SOD protection mechanism against drug-mediated O2.- cytotoxicity.  相似文献   
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