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991.
The relationship between indigenous bacterial floras in the lower genitals and the uterocervical region is of importance due to a barrier-like role against ascending infections through the mechanism of the localized protection at a boundary of the uterocervical region. Therefore, bacterial flora in the uterocervical and uterine regions was studied in cases for which gynecological operations were performed (n = 77). 1. Ratios of incidences of the detection of bacteria on the uterocervical and in the uterine regions were 50/77 (64.9%) and 6/77 (7.8%), respectively. When different age groups are compared, the detection ratio from the uterocervical region was high among patients in the 40 s, and all the cases in which bacteria were detected from the uterine region were in the 40 s. 2. Gram-positive bacteria were detected at a high ratio, and anaerobic bacteria were noted in the uterocervical region, and ratios of detection of Staphylococcus epidermidis, Lactobacillus sp. and Propionibacterium acnes were high. Six strains of Gram-positive bacteria and 1 strain of Candida sp. were noted in the uterine region. 3. When cefmetazole (CMZ) was administered for the prevention of the infections after these panhysterectomy cases examined here, no postoperative infectious diseases nor adverse reactions were noted.  相似文献   
992.
993.
The thermal conversion of 1 alpha-hydroxyprevitamin D3 (1 alpha-OH-previtamin D3) diacetate to 1 alpha-hydroxyvitamin D3 (1 alpha-OH-vitamin D3) diacetate was investigated in five solvents. The fraction of 1 alpha-OH-vitamin D3 diacetate was calculated from the HPLC peak areas (UV detection) of 1 alpha-OH-previtamin D3 diacetate and 1 alpha-OH-vitamin D3 diacetate. When 1 alpha-OH-previtamin D3 diacetate was dissolved in ethanol, benzene, toluene, isopropyl ether, or n-hexane, and heated at 60 degrees C, the yield of 1 alpha-OH-vitamin D3 diacetate increased during the first 4 h, and reached an equilibrium level after 8.5 h. Differences in the ratio of 1 alpha-OH-previtamin D3 diacetate to 1 alpha-OH-vitamin D3 diacetate at thermal equilibrium, and in the rate of the thermal isomerization were observed among these five solvents. Molecular mechanics (MM) calculations were performed in order to estimate solvent effects on conformation for 1 alpha-OH-previtamin D3 diacetate and 1 alpha-OH-vitamin D3 diacetate. The solvent effect was treated by specifying a dielectric constant representative of each of the three solvents: ethanol (polar), n-hexane (nonpolar), and benzene (aromatic). The dielectric constants used were 24.3 for ethanol, 1.5 for n-hexane, and 2.3 for benzene. It is suggested that the conformation of 1 alpha-OH-vitamin D3 diacetate is stabilized in polar solvent. However, the order of conformational stability when solvent effects are included in the calculations is: ethanol greater than benzene greater than n-hexane. This order does not follow the experimental results. The proton NMR chemical shifts of 1 alpha-OH-vitamin D3 diacetate are different in deuterated n-hexane, ethanol, and benzene. The downfield shift of the C-6 vinyl proton of 1 alpha-OH-vitamin D3 diacetate, when compared to the chemical shift in benzene, is 0.15 and 0.11 ppm relative to the chemical shift in n-hexane and ethanol, respectively, and that of the C-7 proton was 0.30 and 0.33 ppm, respectively. No significant proton shift of 1 alpha-OH-previtamin D3 diacetate is recorded in these three solvents. To account for the increased ratio of 1 alpha-OH-vitamin D3 diacetate to 1 alpha-OH-previtamin D3 diacetate ratio in benzene, we suggest that 1 alpha-OH-vitamin D3 diacetate may be stabilized via specific solute-solvent interactions in benzene.  相似文献   
994.
The effects of various types of dietary fat on brush border membrane-bound enzymes in rat intestinal mucosa were examined. Four groups of five rats were pair-fed defined diets for 10 d. The control group was fed a diet containing 57% sucrose and 2% corn oil as a fixed carbohydrate reference; the three experimental groups received diets containing 57% sucrose and 2% corn oil plus 13% fat in the form of medium-chain triglycerides (MCT) or long-chain triglycerides (LCT) (either lard as a highly saturated fat or corn oil as a highly unsaturated fat). Feeding LCT compared to the control diet, decreased sucrase activity in mucosal brush borders of the duodenum and jejunum. In these segments of MCT-fed rats, sucrase activity was similar to that in the control animals. In another experiment, measuring immunoreactive sucrase-isomaltase in jejunal brush border membranes revealed that feeding a high corn oil diet, but not a high MCT diet, led to a reduction in the sucrase catalytic activity per unit weight of enzyme protein, suggesting that the degradation status of sucrase-isomaltase might be altered by the different types of dietary fats. With MCT feeding, jejunal alkaline phosphatase activity was enhanced to a large extent compared to the activity in other groups. Feeding MCT, compared to lard or corn oil, also increased microvillus phospholipids of the jejunal mucosa. These results suggest that MCT, unlike LCT, do not suppress the activity of mucosal microvillus membrane enzymes in rat small intestine.  相似文献   
995.
Summary The present study was undertaken to investigate changes in the crystalline structure and composition of procine enamel mineral during amelogenesis. Special attention was given to the carbonate location in the forming apatite crystal. Enamel samples were obtained from the outer (young) secretory, inner (old) secretory, maturation, and mature (hard) enamel of the permanent incisors of slaughtered piglets. The crystalline structure and composition of these enamel samples were studied using Fourier transform infrared spectroscopy, X-ray diffraction, and chemical analyses. The initial enamel mineral in the outer secretory enamel was rich in acid phosphate and carbonate. The carbonate was mainly substituted for phosphate groups in the apatite crystals of the early (outer) secretory enamel. Developmental advancement from the outer secretory to the inner secretory (as well as early maturation) stages brought about significant changes in crystal parameters, namely, shrinkage and expansion of thec anda unit cell dimensions, respectively, and the shift of av 3 PO4 band to higher wavenumbers in the FTIR spectrum. X-ray diffraction patterns indicated that mineralization during the tissue maturation was characterized by a gradual growth of enamel crystals parallel to thea-axis direction. A most prominent finding was that, with developmental advancement, a decrease in CO3 per unit mass of P (or Ca) in the tissue, and a concomitant increase in the CO3 occupying OH sites in the crystalline lattice became apparent. The overall results may reflect (1) changes in the composition of the medium in which precipitation of enamel carbonatoapatite occurs, (2) initial formation of an acid phosphate such as octacalcium phosphate-like mineral, or (3) modifications of the precipitating phase induced by changes in the kinetics of the mineral formation.  相似文献   
996.
I T Vasil'ev 《Khirurgiia》1990,(9):102-108
The results of treatment of 204 patients with torsion of the sigmoid colon are analysed. Total postoperative mortality was 14.2%. Sixty-eight patients were subjected to palliative operations of the type of ++de-torsion or ++de-torsion in combination with mesosigmoplication and sigmopexy. In this group of patients, 20.5% underwent a second operation for a recurrence of the disease in different periods after the first operation. The mortality rate after palliative operations was 13.2%. Resection of the sigmoid colon with an end-to-end anastomosis was carried out in 87 patients. The postoperative mortality was 13.7%. There were no fatal outcomes among patients who were treated by radical operation carried out in a planned order of preliminary detorsion. In 11.7% of cases, sigmoid torsion was complicated by gangrene. Seven patients (29.1%) died in the postoperative period.  相似文献   
997.
998.
999.
Argon laser pretreatment in Nd: YAG iridotomy   总被引:1,自引:0,他引:1  
Argon laser pretreatment prior to Nd:YAG laser iridotomy may decrease the incidence of operative hemorrhage. In a prospective, randomized clinical trial involving 12 patients (24 eyes), one eye was randomly assigned treatment with the Nd:YAG laser alone, while the other eye was pretreated with argon laser photocoagulation immediately prior to Nd:YAG laser. Eight of the 12 eyes (67%) treated with Nd:YAG laser alone had operative hemorrhages; only 2 of the 12 (17%) pretreated eyes did. Thus, argon laser pretreatment significantly reduced the incidence of hemorrhage during Nd:YAG iridotomy (P = .012).  相似文献   
1000.
The results of diagnosis and treatment of iatrogenic injuries of the extrahepatic biliary tract in 47 patients are analysed. The injury was detected during the operation only in 6 cases, in 41 cases it was revealed on the 1st-6th postoperative day. Intensive conservative therapy was applied in the preoperative period to correct the values of homeostasis and metabolism. Special attention was attached to antibacterial therapy aimed at suppression of ++non-clostridial anaerobic infection. Sixty-three surgical interventions were conducted on 47 patients; 47 of them were restorative or reconstructive, 15 were undertaken for emergency indications, one, for developed postoperative complication. One patient died. Particular importance was attached to adequate draining both in emergency and in reconstructive and restorative operations.  相似文献   
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