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991.
A 24-year-old man had unilateral gross hematuria that required nephrectomy. Pathological examination revealed massive intratubular hemorrhage and frequent deposition of an amorphous and homogeneous material positive for periodic acid, Schiff stain in the corticomedullary junction. This substance had the characteristics of Tamm-Horsfall protein and frequently herniated into the lumen of thin-walled veins of arcuate size. There was no apparent cause for the bleeding. To the best of our knowledge this is the third reported case with these peculiar findings and no apparent cause. We discuss some hypotheses as to the etiopathogenesis of this rare and intriguing condition.  相似文献   
992.
In 570 patients with sporadic primary hyperparathyroidism, the age, sex, symptoms, and preoperative serum calcium values were related to the histopathologic diagnoses, operative findings, and the extent and outcome of parathyroid surgery. Renal stone formation was especially prevalent in younger patients with slight hypercalcemia and parathyroid chief cell hyperplasia, whereas neuromuscular and psychiatric disturbances were overrepresented among older women with higher serum calcium values. Serum calcium concentration was inversely correlated to the proportional incidence of chief cell hyperplasia and positively correlated to the glandular weight of both adenomas and hyperplasias. Glandular size was markedly irregular in chief cell hyperplasia, with increased gland weights of no more than two glands in 78% of patients. During follow-up, for as long as 27 years, normocalcemia was obtained in 91% of patients with adenomas, with failures mainly depending on difficulties in identifying the parathyroid glands. The rate of normocalcemia was lower (80%) among patients with hyperplasia, but an inability to visualize the glands was not a major cause of failure. In patients with hyperplasia with asymmetric and more markedly enlarged glands, it appeared sufficient to remove only the enlarged glands, whereas the findings advocated a subtotal 3- to 3.5-gland resection in patients with more symmetrically or less enlarged hyperplastic glands.  相似文献   
993.
Cytochrome P450-dependent arachidonic acid metabolism in human kidney   总被引:2,自引:0,他引:2  
Cytochrome P450-dependent arachidonic acid metabolism in human kidney cortex from several postmortem subjects has been characterized. Using HPLC and GC/MS, four cytochrome P450-arachidonic acid metabolites were tentatively but not unequivocally identified as epoxyeicosatrienoic acid (EET), dihydroxyeicosatrienoic acid (DHT) and 19- and 20-hydroxyeicosatetraenoic acids, suggesting the involvement of two major cytochrome P450 enzymes, epoxygenase and omega/omega-1 hydroxylases. This pattern of metabolism was similar to that found in rabbit and rat kidneys. The formation of these metabolites was dependent on the presence of NADPH and inhibited by IgG of NADPH-cytochrome P450 (c) reductase. Immunologic studies of renal cytochrome P450 epoxygenase demonstrated that antibodies prepared against human-purified hepatic cytochrome P450 epoxygenase recognized renal enzyme protein and inhibited the enzyme activity by 92%. In contrast, control immunoglobulin did not inhibit renal cytochrome P450 epoxygenase. Antibody inhibition of renal cytochrome P450 epoxygenase demonstrated a degree of conservation of both enzyme proteins between liver and kidney. Antibodies against lauric acid omega/omega-1 hydroxylases (P450 omega) inhibited the formation of omega/omega-1 hydroxylase products, 19- and 20-HETEs. Identical qualitative patterns of arachidonic acid metabolites were observed in all cortical microsomes studied. Interindividual variations were observed in the cytochrome P450-dependent arachidonic acid metabolism, and the activities ranged from 0.031 to 5.027 nmol arachidonic acid converted/mg protein/30 min. which is about a 150-fold difference. However, when the specific activities for total cytochrome P450-dependent arachidonic acid metabolism were calculated, two separate groups could be distinguished, high and low metabolizers of arachidonic acid.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
994.
1. Effects of a novel imidazoindole derivative on cholinergic function were studied in isolated tissue preparations. 2. The compound demonstrated a dose-dependent (10(-11)-10(-9) potentiation (20-60%) of acetylcholine induced tension in guinea pig ileal tissue. 3. Increases in the size of end-plate potentials and nerve evoked muscle twitches were observed in frog nerve-skeletal muscle preparations. 4. Cholinesterase activity was not inhibited. 5. The results suggest that the compound has actions at the post-synaptic muscarinic receptor complex in smooth muscle and causes pre-synaptic increases in ACh release at the neuromuscular junction.  相似文献   
995.
Mortality prognostic factors in chest injury   总被引:2,自引:0,他引:2  
1,026 multiple trauma patients (P) were compared to P with chest injuries (PCT) (407). Severity indices were related to type of thoracic injury and mortality. The Injury Severity Score (ISS), Glasgow Coma Scale (GCS), Trauma Score (TS), CHOP, and the Respiratory Index (RI) were used. The mortality rate of P was 27.1% but increased to 32.9% for PCT (p less than 0.05). We noted that mortality rate was highly dependent on major chest trauma: 68.6% for flail chest (FC), 56% for lung contusion (LC), 42.3% for hemothorax (HA), and 38.1% for pneumothorax (PN). ISS and RI scores for PCT survivors were greater than ISS + RI scores for P survivors (p less than 0.05 and p less than 0.01). ISS values for LC, HA, and PN PCT survivors were greater than the ISS of P survivors (p less than 0.01). Nonsurviving PCTs, especially those with lung contusion, showed a highly significant increase in ISS and RI scores.  相似文献   
996.
Effects of hypothermia on testicular ischemia   总被引:14,自引:0,他引:14  
The ischemic effects of prolonged testicular torsion have been well documented; however, prevention or arrest of the damaging effects of prolonged ischemia has been incompletely studied. Two groups of Sprague-Dawley rats were subjected to varying lengths of bilateral testicular ischemia. Group I underwent normothermic ischemia for two, four, and six hours. Likewise, Group II underwent similar time periods of ischemia, however, after thirty minutes of normothermic ischemia the scrotum of each animal was placed into an ice bath maintained at 4C. Two weeks postoperatively, bilateral orchiectomy was performed. Histology of the testes of the two groups was compared. Neither group revealed significant destruction of the germinal epithelium after two hours of ischemia. Group I revealed only 25% preservation of the germinal epithelium at four hours and only 8% preservation at six hours of ischemia. In contrast, Group II which received ice showed 90% preservation of germinal epithelium at four hours and 85% preservation at six hours of ischemia. We conclude that external ice application significantly preserves seminiferous tubules at four and six hours of ischemic injury in the rat testicle.  相似文献   
997.
998.
999.
Patient history and clinical examination are important for the diagnosis of degenerative joint disease. Here the typical statements of a patient suffering from early osteoarthritis are described and, as far as possible, explained. The joint in question must be systematically examined. Furthermore, the neighboring joints and soft-tissue structures, i.e., muscles, tendons etc., should be examined and evaluated with respect to their importance in hindering the functional chain. The neuroreflectory mechanisms involved herein are described.  相似文献   
1000.
BACKGROUND: The aim was to determine the influence of the socioeconomic status of the family and the hygienic practices in the home on the prevalence of head lice infestation in children. METHODS: The study was carried out by analyzing the answers to a standardized epidemiological questionnaire given to parents of school children aged 4-17 in Bet Shemesh, a medium-sized urban town 25 km from Jerusalem. RESULTS: Of 3,000 questionnaires distributed, 958 (31.9%) were completed and returned. The majority of the children (72.4%) had been previously infested with lice. Half of them had other family members, mainly brothers and sisters, who had been infested in the past with lice. In 97.5% of the families the mother was responsible for examining the children for lice, and for carrying out treatment when infestation was present. An association was found between presence of lice infestation and mother's education, age of child, and frequency of shampooing, combing, and examination for lice. There was no association between infestation rates and mother's country of origin, crowding in the home, and the sharing of combs, brushes, hats, scarves, towels, and clothes. CONCLUSIONS: There is evidence that the incidence of lice infestation depends on the hygienic practices in the home rather than on the socioeconomic status of the family or sharing of personal articles among family members.  相似文献   
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