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101.
Steroid hydroxylase cytochrome P450c17 has been previously purified from microsomal fractions of immature rat livers. In this study, we investigated the expression of P450c17 in rat livers to understand a role of steroidogenesis in the extrasteroidogenic tissue. Upon immunoblot analysis utilizing liver microsomes from rats, P450c17 was detected in 1 and 3 week old rats but not in adult rats. Data from immunohistochemical studies also showed a similar age-dependent expression of P450c17 and indicated that P450c17 detected in immature rat livers is localized in cells surrounding interlobular veins. This age-dependent expression of P450c17 in rat livers was observed in both sexes. Upon enzymatic analysis utilizing microsomal fractions from livers, levels of 17alpha-hydroxylase and 17,20-lyase activity for pregnenolone and progesterone increased by 3 weeks and dramatically reduced at 7 weeks, which is consistent with the expression level of P450c17. These data clearly indicate that P450c17 is expressed in immature rat liver to produce 17alpha-hydroxysteroids and C19-steroids. Based upon immunoblot analysis, the expression level of P450c17 in immature rat livers was approximately one third of that in testis. Compared expression level of P450c17 and total volume of organs between liver and testis, the total amount of steroid metabolites produced by liver P450c17 could be greater than that produced by gonadal P450c17. Because of the absence of P450c17 in rat adrenal glands, rat liver could be the major site for producing 17alpha-hydroxysteroids and C19-steroids in this particular period of life. Although physiological products formed by P450c17 in liver and their roles remain to be elucidated, this study suggests a large capacity of prepubertal rat liver for participating the production of steroid hormones and a putative importance of 17alpha-hydroxysteroids and C19-steroids, such as cortisol and androstendione, which are generally believed to be minor components of steroid hormones in rodents.  相似文献   
102.
BACKGROUND: Outpatient complications leading to hospital readmission after hospitalization for trauma have not been examined. METHODS: A retrospective chart review of all trauma victims admitted to a Level 1 trauma center from January of 1990 to January of 1995 was performed to characterize patients who required readmission after hospitalization for trauma. Risk factors for readmission were determined by stepwise regression analysis. RESULTS: Of 15,463 trauma admissions, 209 patients (1.4%) required readmission, 84% within 30 days, 71% within 14 days. Reasons for readmission included wound (29%), abdominal (29%), pulmonary (18%), and thromboembolic (19%) complications. Fifty of the patients (24%) readmitted with a complication required an operation. Risk factors for readmission included: operation during first hospitalization (p < 0.0001), penetrating injury (p = 0.0001), and advanced age (p = 0.0001). Injury Severity Score, length of hospitalization, and gender were not independent predictors of readmission. CONCLUSIONS: Outpatient complications leading to readmission after hospitalization for trauma are not common; however, many are serious and require operative intervention. Because most complications were identified by the second week after discharge, outpatient follow-up visits should be scheduled within 7 to 14 days. Based on our findings, we recommend protocols be established to ensure follow-up for trauma patients, especially those who have had an operation, were victims of penetrating injury, or those > 65 years of age.  相似文献   
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AIM: The neonatal resuscitation program (NRPG) was first introduced in our hospital to replace the traditional resuscitation (TR) program in 1993. TR has been in existence in China for a long time. The implementation of NRPG was timely in reducing the number of infant mortality and also to disseminate to the many hospitals in China which are still practising TR. METHOD: A perspective study of 4,751 newborns with 366 asphyxiated babies in a period of 2 years was carried out. A previous sample of 1,722 live births under the TR program was compared as a controlled group statistically. RESULTS: From August 1993 to August 1995, when NRPG was exclusively implemented in our hospital, only 16 newborns died within 7 days, out of 4,751 births (3.4%) with 2 deaths in the delivery room. Seventeen newborns died within 7 days out of 1,722 births (9.9+) in the TR group, with 10 deaths in the delivery room. From the data shown, it can be clearly seen that perinatal neonatal mortality rate was reduced almost 3 times after NRPG was implemented (chi(2) = 10.54, p < 0.01). The follow-up results of 21 cases of severe asphyxia at 2 months--1 year of age were normal except for one with cerebral palsy. CONCLUSIONS: Our study showed that NRPG was indeed a very effective and feasible technique during the delivery process in the reduction of neonatal mortality. It is important to disseminate widely the knowledge and technique of NRPG in places where TR is still being widely practiced especially in developing countries.  相似文献   
105.
In mice, peritoneal B cells are composed of a unique B-1 cell population which can repopulate the intestinal lamina propria with IgA-producing cells, as well as contribute to the majority of serum IgM. In this study, peritoneal lymphocytes from patients starting continuous ambulatory peritoneal dialysis (CAPD) and from women undergoing bilateral tubal ligation (BTL) were analysed for the presence of a B-1 cell population as well as the expression of potential homing receptors. Up to 63% of the peritoneal B cells express surface antigen CD5, and most peritoneal lymphocytes express the mucosal homing receptors, alpha4 beta7 and alphaE beta7. When analysing serial samples collected from patients from the beginning of dialysis to 1 year, no marked changes were observed in serum or salivary immunoglobulin levels, although the peritoneal lymphocyte population was reduced by 50%. These data suggest that the phenotype of human peritoneal B-1 cells is similar to that of mice, but the contributions to the immune system may differ.  相似文献   
106.
The Temperament and Character Inventory (TCI) is a self-report personality questionnaire based on Cloninger's psychobiological model of personality, which accounts for both normal and abnormal variation in the two major components of personality, temperament and character. Normative data for the Swedish TCI based on a representative Swedish sample of 1,300 adults are presented, and the psychometric properties of the questionnaire are discussed. The structure of the Swedish version replicates the American version well for the means, distribution of scores, and relationships within the between scales and subscales. Further, the Swedish inventory had a reliable factor structure and test-retest performance. The results of this study confirm the theory of temperament and character as a seven-factor model of personality.  相似文献   
107.
BACKGROUND: Ardeparin sodium has recently received approval by the Food and Drug Administration for prophylaxis against venous thromboembolism in patients undergoing elective total knee replacement. However, this low-molecular-weight heparin has not been previously evaluated in a randomized controlled trial for treatment of established acute deep venous thrombosis. METHODS: The study included patients with ultrasound-documented acute symptomatic deep venous thrombosis of the legs. They had to be deemed appropriate for discharge home to receive subcutaneous low-molecular-weight heparin. Patients were randomized to receive ardeparin with a 2-day hospitalization or unfractionated heparin sodium with a 5-day hospitalization. Both groups received warfarin sodium. Follow-up ultrasound examinations were undertaken at 6 weeks. RESULTS: Of the 80 patients enrolled, 75 had follow-up ultrasonography. Evaluation of baseline vs 6-week venous scans demonstrated that, overall, 31 of the 39 ardeparin-treated patients improved, compared with 21 of the 36 patients assigned to receive unfractionated heparin (P=.05). The 95% confidence interval for the difference in improvement was 0.6% to 42% in favor of ardeparin. Median charges for ardeparin and unfractionated heparin were $2815 and $6500, respectively (P<.001). There were no differences in bleeding or patient satisfaction between the 2 groups. CONCLUSIONS: The results of this small preliminary trial suggest that ardeparin can be administered effectively and safely to selected patients with acute deep venous thrombosis and that, with proper nursing and home services, it can help decrease the duration of hospitalization.  相似文献   
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109.
OBJECTIVE: To evaluate the effect of chocolate cyst fluid on the proliferation of cultured human endometrioma cells and to assay the concentration of transforming growth factor-B1 in this fluid. DESIGN: Controlled in vitro study. SETTING: Department of Obstetrics and Gynecology, State University of New York Health Science Center. PATIENT(S): Five women with ovarian endometriomas. INTERVENTION(S): Endometrioma tissue and chocolate fluid from five different patients were entered in this study. MAIN OUTCOME MEASURE(S): Endometrioma cell proliferation in culture with and without chocolate cyst fluid. RESULT(S): Chocolate cyst fluid increased the proliferation of endometrioma cells compared with controls. Also, high concentrations of transforming growth factor-B1 were found in cysts' fluid. CONCLUSIONS: Chocolate cyst fluid has a growth-enhancing effect on endometrioma cells. One promoting growth factor is transforming growth factor-B1.  相似文献   
110.
We assessed mechanisms of acetylcholine- and bradykinin-induced relaxations in human omental resistance vessels. Ring segments (approximately 200 microns normalized ID) were dissected from omental biopsies obtained from women at laparotomy (nonpregnant) or at cesarean delivery (pregnant) and were studied under isometric conditions in a Mulvany-Halpern myograph. All arginine vasopressin-preconstricted vessels relaxed in a strictly endothelium-dependent manner to acetylcholine and bradykinin; maximal relaxations were not decreased by either NG-nitro-L-arginine or indomethacin. By contrast, bradykinin failed to relax vessels that had been preconstricted with potassium gluconate. In the combined presence of NG-nitro-L-arginine and indomethacin, addition of charybdotoxin, a selective antagonist of some calcium-sensitive potassium channels, did not inhibit maximal bradykinin-induced relaxation. By contrast, addition of 10 mmol/L tetraethylammonium chloride abolished relaxation in vessels from nonpregnant women but not in vessels from gravidas. We conclude that bradykinin relaxes these human resistance arteries in an endothelium-dependent but predominantly nitric oxide- and prostanoid-independent manner; relaxation likely depends on the action of an endothelium-derived hyperpolarizing vasodilator. Furthermore, in striking contrast to mechanistic insights from animal studies, human pregnancy appears to augment a mechanism of endothelium-dependent relaxation in these vessels that is insensitive to the inhibitors noted above. Whether a similar novel vasodilator mechanism in vivo contributes to the physiological vasodilation that characterizes human gestation or whether failure of such a mechanism might lead to preeclampsia remains the subject of future study.  相似文献   
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