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991.
Inherited defects of the natural coagulation inhibitors predispose patients to thrombosis. These disorders have similar clinical presentations with a strong family history of thrombosis, episodes of recurrent venous thromboembolism, beginning in early adulthood. We report a case of upper gastrointestinal bleeding in a patient with portal hypertension due to portal-vein thrombosis secondary to hereditary protein C deficiency, an association that has seldom been reported.  相似文献   
992.
The erythrocyte alanine aminotransferase (E-ALAT) activity with and without in vitro stimulation by pyridoxal phosphate of 60 healthy adolescents was measured before and after 6 weeks of supplementation with different water-soluble vitamins. The subjects who were divided into six groups received placebo (lactose tablets), pyridoxine, pyridoxine + ascorbic acid, pyridoxine + iron, pyridoxine + riboflavin and multivitamin supplements, respectively. Presupplementation E-ALAT activity increased significantly (p less than 0.05) for all supplemented subjects after 6 weeks. Deficient subjects (E-ALAT) index less than 1.16) however failed to respond to a combination of pyridoxine + ascorbic acid or multivitamins. It is suggested that pyridoxine in multivitamin preparations must exceed 1 mg to produce any useful improvement in vitamin B6 status of adolescents on suboptimal vitamin B6 intakes.  相似文献   
993.
The aim of this study was to investigate factors associated with life dissatisfaction in symptomatic patients (n = 144) with chest pain subsequently diagnosed as coronary heart disease (CHD) by coronary angiography. Life dissatisfaction was assessed with a four-item life satisfaction scale (LS), depression with the 21-item Beck Depression Inventory (BDI) and other psychiatric symptoms with the symptom check list (SCL). DSM-III-R Axis I and Axis II psychiatric diagnoses were performed by means of the Structured Clinical Interview. All assessments took place one day before angiography. Twenty-four per cent of CHD patients were dissatisfied with their lives. Life dissatisfaction was associated with being unmarried. Dissatisfied patients had Axis I mental disorders and Axis II personality disorders more frequently than others. Psychiatric and depressive symptoms according to the SCL and BDI, respectively, were also higher among dissatisfied patients. In multiple logistic regression analyses, mental disorders were related to life dissatisfaction when age, sex, employment status, New York Heart Association class, duration of chest pain symptoms and work load were controlled in the model. Married subjects had a lower probability of being dissatisfied with their lives than other subjects (Odds Ratio, OR: 0.23). When BDI scores were included in the model, the only factor independently associated with life dissatisfaction was the severity of depressive symptoms (OR: 1.81). To conclude, life dissatisfaction is not primarily determined by the severity of CHD but by the existence of depressive symptoms.  相似文献   
994.
The formation of DNA adducts was investigated in mouse fibroblasts from two different tissues--embryos and adult lung--after incubation with dibenzo[a,e]fluoranthene (DBF) or its major proximate metabolites. The nuclease P1 modification of the 32P-postlabeling method was adapted for detection of DBF-DNA adducts. Quantitative and qualitative differences were observed in the metabolic activation mediated by the two cell types. DBF-DNA adducts generated three major spots reproducibly, and more than ten spots of medium or weak importance. The highest level of DNA binding occurred via the DBF-bay region vicinal dihydrodiol epoxide but with significant differences in the quantitative distribution of adducts. Striking qualitative differences were observed when lung fibroblasts were incubated with the DBF-pseudo bay region dihydrodiol (DBF-12,13-DHD). The spots representing adducts induced in embryo fibroblasts by DBF-3OH-12,13-DHD, a further metabolite of DBF-12,13-DHD, were totally absent from chromatograms of lung cells. These results show that both embryo and lung fibroblasts can activate DBF but that different cytochrome P-450 forms and substrate affinities are involved. The finding that different activation systems may be present in subcategories of the same tissue, may provide a partial explanation for the wide variations in sensitivity to carcinogens among species, organs and tissues.  相似文献   
995.
The pattern of infection inGlossina morsitans morsitans andG. m. centralis membrane-fed on eland, buffalo or goat blood mixed withTrypanosoma congolense orT. brucei was studied from day 1 to day 10. Tsetse were initially permissive vectors, with most flies harbouring infections of 104–105 parasites on day 3. However, after a second blood meal on day 3, flies cleared many infections withG. m. morsitans clearing more infections thanG. m. centralis. Infective feeds of goat blood consistently increased final infection rates by limiting the number of infections lost between days 3 and 6. In further experiments withG. m. morsitans only, this effect was replicated by feeding flies on erythrocytes but not on serum. These results suggest that compounds from some mammalian erythrocytes match the target specificity ofG. m. morsitans midgut lectins and, hence, have a protective effect on trypanosome establishment in the fly.  相似文献   
996.
HLA alleles were studied in Kuwaiti patients with Systemic lupus erythematosus (SLE). Although significant association of B5, B8, and DR3 has been reported in the literature, the most common phenotype for our patients is A3, DR2 as susceptible alleles and DQ1 as a protective gene.  相似文献   
997.
Osteotomies of the distal femur were fixed with two self-reinforced poly-L-lactic acid (SR-PLLA) plates and metallic screws placed through the plates on each side of the femur in 23 adult rabbits. They were followed-up after 3, 6, 12 and 24 weeks. After killing, radiological, histological, microradiographic and oxytetracycline fluorescence studies were performed. Except for one histologically confirmed fibrotic non-union at 24 weeks, the osteotomies healed, including one involving a rabbit which had suffered an ipsilateral femoral shaft fracture of unknown cause. No malformations were observed, and the macroscopically detected swelling was a normal postoperative reaction. This study showed that SR-PLLA plates implanted on both sides on the bone are suitable for the fixation of weight-bearing cancellous bone osteotomies in rabbits.  相似文献   
998.
Background: Ketamine is a potent bronchodilator that, in clinically used concentrations, relaxes airway smooth muscle in part by a direct effect. This study explored the role of calcium concentration (Ca2+) in this relaxation.

Methods: Canine trachea smooth muscle strips were loaded with the fluorescent probe fura-2 and mounted in a spectrophotometric system to measure force and intracellular calcium concentration ([Ca2+]i) simultaneously. Calcium influx was estimated using a manganese quenching technique. Cyclic nucleotides in the airway smooth muscle strips were measured by radioimmunoassay.

Results: In smooth muscle strips stimulated with submaximal (0.1 micro Meter) and maximal (10 micro Meter) concentrations of acetylcholine, ketamine caused a concentration-dependent decrease in force and [Ca2+]i. The sensitivity of the force response to ketamine significantly decreased as the intensity of muscarinic receptor stimulation increased; the median effective concentration for relaxation induced by ketamine was 59 micro Meter and 850 micro Meter for tissue contracted by 0.1 micro Meter or 10 micro Meter acetylcholine, respectively (P < 0.05). In contrast, the sensitivity of the [Ca2+] sub i response did not depend on the intensity of muscarinic receptor stimulation. Ketamine at 1 mM significantly inhibited calcium influx. Ketamine did not significantly increase cyclic nucleotide concentrations.  相似文献   

999.
Objective: To determine whether the quality of infiltrations in chest radiographs can accurately predict the histological extent of fibrotic change in patients with acute respiratory distress syndrome (ARDS). Design: Retrospective clinical investigation. Setting: Intensive care unit (ICU) of a university teaching hospital. Patients and methods: Of 47 patients treated with extracorporeal membrane oxygenation (ECMO) for severe ARDS over a 5-year period, 23 patients underwent open lung biopsy at thoracotomy for treatment, mostly of pneumothorax. Chest films obtained by portable chest roentgenography preceding the operation were reviewed retrospectively and compared to the histomorphological results of the lung specimen. Results: Chest radiographs displayed mixed alveolar-reticular opacification in 60.2 %, alveolar patterns in 22.9 % and reticular opacities in 10.5 %. In 0.4 % there were no infiltrates, 6 % could not be evaluated because of insufficient quality. There was no relevant difference between the right and left lungs. Subdividing patients into two groups according to the histological results of either absent or mild (1) or severe (2) lung fibrosis, we found an alveolar haziness in 12.3 % in group 1 compared with 28.2 % in group 2, while reticular characteristics were identified in 13 % and 11 %, respectively. Conclusions: The most common opacity in chest radiographs of patients with severe ARDS treated with ECMO is mixed alveolar-reticular opacification. Severe lung fibrosis is not positively correlated with a reticular radiographic pattern. ECMO does not lead to specific radiological changes in conventional radiograms, contrary to clinical findings that treatment with ECMO might induce pleural or pulmonic haemorrhage, especially in the earlier days when systemic heparinization had to be used instead of the heparin-coated tube-surfacing. Received: 24 November 1997 Accepted: 20 July 1998  相似文献   
1000.
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