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991.
Triton X-100 and the bile salts, cholate and deoxycholate, detergents often used in the solubilization of monoamine oxidase (MAO) from mitochondria, have been found to cause an inhibition of the enzyme activity. With beef brain mitochondria, it was found that there was a differential effect of Triton X-100 on the putative MAO types A and B, with MAO-A being more susceptible to inhibition by Triton X-100. This was indicated by the greater loss of serotonin-deaminating than of phenyl ethylamine-deaminating activity in the presence of Triton X-100. Although the bile salts also caused substantial inactivation at concentrations above 0.1%, no differentiation between MAO types could be made. Kinetic studies of the inhibition by Triton X-100 indicated two different mechanisms were occurring with the two MAO types. The inhibition was competitive for MAO-A, but uncompetitive for MAO-B. Removal of Triton X-100 by co-polymer beads restored some, but not all of the activity for both MAO-A and MAO-B types. This suggests that the activity loss may have been due in part to inactivation when the enzyme was separated from the mitochondrial membrane.  相似文献   
992.
Effect of leptin on healing of colonic anastomoses in rats   总被引:8,自引:0,他引:8  
BACKGROUND/AIMS: Anastomotic leaks are continuing to be the source of major morbidity in colorectal surgery. Previous studies have shown that leptin acts as a growth factor for several cell types. The aim of this study was to evaluate the effect of leptin on healing of colonic anastomoses in rats. METHODOLOGY: Forty-eight rats were divided into 5 groups. Group I (n=8) sham; group II (n=10) control; right colonic anastomosis, group III (n=10); following right colonic anastomosis, treated with leptin twice-daily 1 mg/kg intraperitoneally, group IV (n=10); before right colonic anastomosis, 45 min of colonic ischemia has been created, group V (n=10); following 45 min of colonic ischemia and right colonic anastomosis, leptin was given twice-daily 1 mg/kg intraperitoneally. On the 7th postoperative day relaparotomy was performed. Bursting pressure (BP), tissue hydroxyproline concentrations (THPC), and histopathologic properties of anastomoses; vascular tissue proliferation (VTP), collagen tissue proliferation (CTP), polymorphonuclear leukocyte infiltration (PMNLI), mononuclear leukocyte infiltration (MNLI) were analyzed and results were compared statistically. RESULTS: BP and THPC were found to be significantly higher in group III and group V in comparison with group II and group IV respectively (P<0.05). Histopathologically, leptin significantly increased VTP, CTP, MNLI (P<0.001), and significantly decreased PMNLI (p<0.05) on non-ischemic and ischemic colonic anastomoses. CONCLUSIONS: Leptin can be used safely in colorectal surgery since it accelerates the healing of colonic anastomoses.  相似文献   
993.
The effects of systemic theophylline administration on spike-wave discharge (SWD) frequency in genetically absence epileptic Wistar Albino Glaxo/Rijswijk (WAG/Rij) rats are investigated. After an hour of baseline recording, animals were injected intraperitoneally (ip) with 5, 10, and 20mg/kg theophylline and electroencephalograms (EEGs) were recorded for 2h postinjection. Then, the number and total duration of SWDs were analyzed. Spontaneous behaviors of the animals was also observed before and after drug administration. Our results show that systemic administration of theophylline suppresses the occurrence of SWDs in a dose-dependent manner. The greatest suppression was seen in the group administered 20mg/kg theophylline. Theophylline also induced a mild increase in exploratory and automatic behavior. These results indicate that blockage of adenosinergic receptors via the methylxanthine derivative theophylline decreases the occurrence of SWDs, probably by augmenting the efficacy of excitator neurotransmission and increasing vigilance and arousal levels.  相似文献   
994.
Although recurrence of amyloid A deposition in the allograft can be seen in patients with secondary amyloidosis due to familial Mediterranean fever (FMF), renal transplantation remains to be a choice of treatment for end-stage renal disease. The aim of this study was to determine short- and long-term results of renal transplantation in patients with FMF amyloidosis. We compared the outcomes of 17 patients with FMF amyloidosis among 431 (3.9%) transplants with 209 control patients. We observed 93% and 94% graft and patient survivals at 1 year, and 89% and 90% at 5 years. Also, the mean serum creatinine levels at 1 and 5 years posttransplant were similar. Recurrence of amyloidosis was documented in two allograft recipients presenting with nephrotic range proteinuria (12%), one of whom lost the allograft due to recurrence. Eleven patients had FMF gene analysis. The results of MEFV mutation analyses were: M694V/M694V homozygote in six patients, M694V/EQ148 in one patient, M694V/V726A in one patient, 680M-I/E148Q in one patient. FMF gene analysis was negative in two patients. Recurrence was noticed in one patient with M694V/M694V, while the other did not have an FMF gene analysis. Colchicine was reduced in nine patients due to side effects. In conclusion, the long-term outcomes of transplantation in patients with amyloidosis secondary to FMF is similar to that in the general transplant population and maintenance colchicine, even at low dose, appears to effectively prevent recurrence of amyloidosis in the allograft.  相似文献   
995.
996.
The association between daily variations in ambient concentrations of nitrogen dioxide (NO2) and mortality was examined in 12 of Canada's largest cities, using a 19-yr time-series analysis (from 1981-1999). The authors employed parametric statistical methods that are not subject to the recently discovered convergence and error estimation problems of generalized additive models. An increase in the 3-d moving average of NO2 concentrations equivalent to the population-weighted study mean of 22.4 ppb was associated with a 2.25% (t = 4.45) increase in the daily nonaccidental mortality rate and was insensitive to adjustment for ozone, sulfur dioxide, carbon monoxide, coefficient of haze, size-fractionated particulate mass, and the sulfate ion measured on an every-6th-day sampling schedule. The 3-d moving average of NO2 was sensitive to adjustment for fine particulate matter measured daily during the 1998-2000 time period.  相似文献   
997.
This study was designed to determine whether betamethasone has any effect on 1-hour (50-g) glucose screening test in nongestational diabetic pregnancy, and if any exists, to determine if this effect is transient or permanent. If the effect is temporary, the study was designed to determine the duration of this glucose intolerance effect and to determine the timing of 1-hour glucose screening test after betamethasone usage. One hundred fourteen pregnant women with a diagnosis of preterm labor at 24 to 34 weeks gestation were enrolled into the prospective study. One-hour glucose screening test was performed before initiation of hydration treatment. Forty pregnant women with normal 1-hour glucose results, who also had responded to hydration therapy, made up our study group. Twenty-four hours, 72 hours, and 1 week after administration of betamethasone, 50-g glucose challenge tests were again performed. A 3-hour glucose tolerance test was performed in pregnant women, whose 1-hour screening test had been positive 1 week after corticosteroid administration. In the evaluation of data, one-way, variance analysis and Tukey's multiple comparison test were used. The mean value of 1-hour glucose results of 50-g challenge test at the 24 hours was significantly higher than the mean value of 1-hour glucose results of the test done initially before betamethasone administration and than those of the tests done at 72 hours and 1 week (p < 0.001 for these three groups). There was no statistically significant difference between the mean values of 1-hour glucose results of the test done before betamethasone administration and both the results of the tests done at 72 hours (p = 0.96) and 1 week (p = 0.99), separately. There was no significant difference between the mean 1-hour glucose results of the tests at 72 hours and 1 week (p = 0.99). The test results were positive in 42.5%, 10%, and 5% of the patients, respectively at 24 hours, 72 hours, and 1 week. The betamethasone administration significantly deteriorates 1-hour glucose screening test results in the nongestational diabetic patients but this effect of betamethasone is transient. Because of its high false-positivity at 24 hours (42.5%) and at 72 hours (10%) in women with initial negative 1-hour glucose screening test, we suggest that 1-hour glucose screening test in pregnant women be postponed at least 1 week after betamethasone administration or perform the test before administration of betamethasone.  相似文献   
998.
Surgical outcomes of cerebellar tumors in children   总被引:1,自引:0,他引:1  
Cerebellar tumors in childhood are generally associated with a favorable outcome if they are managed appropriately. 27 cases of pediatric cerebellar tumors, operated over a 7-year period, are presented. Histopathological diagnoses were as follows: pilocytic astrocytoma (48.2%); medulloblastoma (22.2%); ependymoma (18.5%); fibrillary astrocytoma grade III (3.7%); cystic oligodendroglioma (3.7%), and hemangioblastoma (3.7%). Microscopic gross total resection was achieved in 16 (59.3%) of 27 cases. The total removal of pediatric cerebellar tumors without neurological deficit is possible with appropriate microsurgical techniques excluding brain stem invasion. The follow-up periods must be shorter if brain stem invasion exists. Radiotherapy and chemotherapy are the adjuvant therapies according to the pathological diagnosis and the patient's age.  相似文献   
999.
Aridoğan IA  Ilkit M  Izol V  Ates A 《Mycoses》2005,48(5):352-356
The Malassezia yeast are members of the normal human cutaneous flora in adults. They also are reported as part of the microflora of the male genital region in mostly uncircumcised males. It has been reported that Malassezia sympodialis and Malassezia globosa are the most frequent yeast belonging to the resident microflora of the penis as in other human skin areas. The aim was to evaluate the prevalence of Malassezia and Candida yeast colonisation on the glans penis of circumcised males. Impression preparations were made on modified Dixon agar. The isolates were identified by morphological and physiological characteristics. A total of 245 circumcised males were included in the study. Of the 245 patients examined, 55 (22.4%) were found to have a mycologically proven yeast fungi on their glans penis. In 17 (30.9%) Malassezia, in 36 (65.5%) Candida, in one (1.8%) Malassezia and Candida, and in one (1.8%) Saccharomyces strains were detected. Malassezia furfur (66.7%) was the most common species among the lipophilic yeast, followed by Malassezia globosa (11.1%), Malassezia obtusa (11.1%) and Malassezia slooffiae (11.1%). Candida albicans was the most common non-lipophilic yeast (46.0%), that was isolated among the other yeast, followed by unidentified Candida strains (18.9%), Candida tropicalis (8.1%), Candida glabrata (8.1%), Candida parapsilosis (8.1%), Candida zeylanoides (5.4%), Candida guilliermondii (2.7%) and Saccharomyces cerevisiae (2.7%). The results of this study showed that Malassezia species were also colonised like Candida on the glans penis of circumcised males.  相似文献   
1000.
PURPOSE: Hyperprolactinemia is a common hormonal disorder in women that may affect the phases of female sexual function (FSD). We investigated sexual function in patients with hyperprolactinemia. MATERIAL AND METHODS: A total of 25 women with primary hyperprolactinemia and 16 age matched voluntary healthy women who served as the as control group were evaluated with a detailed medical and sexual history, including a female sexual function index (FSFI) questionnaire and the Beck Depression Inventory. Serum prolactin, dehydroepiandrosterone sulfate, free testosterone, androstenedione, 17alpha-hydroxyprogesterone, estradiol, free thyroxin and thyrotropin were measured. These variables were compared statistically between the 2 groups. RESULTS: Except for prolactin serum hormone levels in women with hyperprolactinemia were not different from those in the control group. The median total FSFI score was 23.40 (IQR 17.70 to 27.30) in the hyperprolactinemic group, whereas healthy women had a median total FSFI score of 31.10 (IQR 27.55 to 32.88, p < 0.0001). FSD was diagnosed in 22 of 25 patients (88%), while 4 of 16 healthy women (25%) had FSD (p = 0.03). Desire (p = 0.001), arousal (p < 0.0001), lubrication (p = 0.001), orgasm (p = 0.001), satisfaction (p = 0.07) and pain (p = 0.003) domain scores were also significantly lower in women with hyperprolactinemia. Total FSFI (p = 0.009, r = -0.405), desire (p = 0.001, r = -0.512), arousal (p = 0.002, r = -0.466), orgasm (p = 0.026, r = 0.348) and satisfaction (p = 0.041, r = -0.320) scores negatively correlated with mean prolactin but not with the other hormones measured. CONCLUSIONS: A significant percent of women with hyperprolactinemia whom we evaluated had sexual dysfunction. No hormonal changes other than prolactin and no depression was found as a cause of FSD.  相似文献   
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