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We performed a study on infants and children with hypothyroidism to determine the effect of hypothyroidism and its correction on components of the IGF system. A total of 35 patients were subdivided into four groups based on age and severity of the disease. Serum concentrations of immunoreactive IGF-I, free IGF-I, IGFBP-2 and IGFBP-3 were measured before and after treatment and compared to controls matched for age, sex and puberty. Baseline total IGF-I (TIGF-I) concentrations were significantly lower prior to treatment in the infants with severe hypothyroidism and increased significantly after thyroxine therapy. Baseline free IGF-I (FIGF-I) concentration was significantly lower prior to treatment in infants with severe hypothyroidism when compared to controls but did not increase significantly after treatment. In infants with severe and compensated hypothyroidism, IGFBP-3 concentrations prior to treatment were lower when compared to controls. These concentrations increased during treatment. Baseline IGFBP-2 levels did not differ from the control values in both these groups but decreased significantly after correction of the hypothyroidism. Although these changes appeared to occur with thyroxine therapy, multiple regression analysis suggested that age was a more important determinant of the changes observed in these parameters than serum thyroxine concentration. In children with acquired hypothyroidism no difference in any of these parameters was noted between hypothyroid patients and controls. TIGF-I increased significantly on thyroxine therapy, but the difference was small. No significant differences were noted in other measured parameters with thyroxine therapy. In older children with compensated hypothyroidism no significant differences were noted in any of the measured parameters in the pretreatment, post-treatment and control groups. In conclusion, although changes appear in TIGF-I, IGFBP-3 and IGFBP-2 in infants with congenital hypothyroidism when they are treated with thyroxine, age appears to be the more important determinant of these changes than does thyroxine concentration. In older children with acquired hypothyroidism, TIGF-I and FIGF-I levels were not significantly lower than in age- and sex-matched controls. After treatment only TIGF-I levels increased.  相似文献   
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OBJECTIVE: To compare the efficacy of electrocautery with that of the suture method for achieving hemostasis of the cervical cone bed. METHODS: We performed a retrospective chart review of all patients who underwent cold-knife conization of the cervix over a 5-year period. Patients were categorized into two groups: the cautery group, in which the cone bed was electrocauterized with a hand-held electrocoagulation device; and the suture group, in which hemostasis was achieved by a continuous locking suture placed circumferentially around the cone bed. Outcome measures evaluated include estimated blood loss, operative time, and incidence of complications, including secondary hemorrhage, cervicitis, and cervical stenosis. Data were analyzed by Student t test, chi(2) test, linear regression, and multiple logistic regression where appropriate. RESULTS: There were 156 women in the cautery group and 35 in the suture group. The cautery group had significantly lower estimated blood loss (27 mL versus 101 mL; P <.01) and shorter operative time (34 versus 43 minutes; P <.01) than the suture group. The procedure-related complication rate was 6.4% in the cautery group, compared with 14.3% in the suture group (P = nonsignificant). A higher use of lateral sutures, vasopressors, and thrombotic agents was seen in the cautery group. However, even after adjusting for these variables, mean estimated blood loss (33 mL, P <.01) and mean operative time (34 minutes, P <.01) were significantly less in the cautery group than in the suture group. CONCLUSIONS: Cauterization of the cone bed is superior to suture as a method of achieving hemostasis, with significantly less blood loss and shorter operative time.  相似文献   
79.
Purpose. Sterically stabilized phospholipid micelles (SSMs) composed of poly(ethylene glycol-2000)-grafted distearoyl phosphatidylethanolamine (PEG(2000)-DSPE) are new and promising lipid-based carriers for water-insoluble drugs. This study investigates and compares sterically stabilized mixed micelles (SSMM), composed of (PEG(2000)-DSPE) plus egg-phosphatidylcholine, with SSM as a novel delivery system for improved solubilization of water-insoluble drugs using paclitaxel as a model. Methods. Paclitaxel was solubilized in SSM (P-SSM) and SSMM (P-SSMM) by coprecipitation and rehydration with isotonic 0.01M HEPES buffer, pH 7.4. After separation of excess drug by centrifugation, mean particle size and morphology of particles in the supernatant were determined by quasi-elastic light scattering and transmission electron microscopy. The solubilization potentials of SSMM and SSM for paclitaxel were determined by reverse phase high pressure liquid chromatography (RP-HPLC). Cytotoxic activity of paclitaxel in SSMM, SSM, and dimethyl sulfoxide (10% DMSO) was determined against human breast cancer cells (MCF-7). Results. Mean hydrodynamic diameter of P-SSMM and P-SSM were 13.1 ± 1.1 nm and 15 ± 1 nm (n = 3), respectively. SSMM solubilized 1.5 times more paclitaxel than SSM for the same total lipid concentration. Solubilized paclitaxel amount increased linearly with an increase in lipid concentration. A therapeutically relevant lipid concentration (15 mM) of SSMM solubilized 1321 ± 48g/ml of paclitaxel. Paclitaxel in the absence of sufficient SSM aggregated to form lipid-coated crystals. P-SSMM, P-SSM, and paclitaxel in DMSO had comparable cytotoxic activities against MCF-7 cells. Conclusions. SSMM showed increased solubilization potential compared with SSM while retaining all of its own advantages. Therefore, it can be used as an improved lipid-based carrier for water-insoluble drugs.  相似文献   
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A pilot study of 29 patients for research on clinical depression employed the framework of cultural epidemiology to examine illness-related experience, meaning, behaviour with a Bengali version of the explanatory Model Interview Catalogue (EMIC). This report examined patterns of distress and stigma with reference to the most troubling patient-specified symptom. All subjects were psychiatric outpatients in the Institute of Psychiatry, Calcutta, and met Diagnostic and Statistical Manual (DSM)-IV criteria for a major depressive episode. Only 5 patients (17.2%) identified sadness as the most troubling problem, and 48.3% specified pains and other somatic symptoms instead. An internally consistent stigma scale with Cronbach's alpha of .67, comprised 13 items, was used to assess stigma. In addition to the scale score for each subject, the contribution of each item was reported and compared. A suggestive, though not significantly lower value of the stigma score for patients reporting somatic symptoms as most troubling, compared with sadness, was consistent with findings from prior studies showing a positive relationship between the magnitude of depression and stigma. These findings are discussed with reference to their impact on recognition and help seeking among patients, and recognition and management of depression by general practitioner. Culturally distinctive presentations and social contexts of depression and other mental illnesses should be addressed in professional training and public health communications.  相似文献   
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