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71.
氯化四乙基铵及维拉帕米对家兔缺血心肌不应期的影响   总被引:1,自引:0,他引:1  
实验比较了K+通道阻断剂氯化四乙基铵(TEA)及Ca2+通道阻断剂维拉帕米(verapamil,Ver)对家兔缺血性心室肌不应期(ERP)的影响。结果表明,阻断冠脉10min及30min后,缺血中心区(CIZ)和缺血边缘区(BIZ)心肌ERP比缺血前均明显缩短,而TEA和Ver均能延长急性缺血性心肌的ERP,可能对心肌缺血引起的心律失常有预防作用。  相似文献   
72.
Hepatic spiral CT: reduction of dose of intravenous contrast material   总被引:13,自引:0,他引:13  
  相似文献   
73.
在2型糖尿病患者中,反映炎症和内皮功能障碍的生物标志已经与心血管疾病和代谢调节联系起来。二甲双胍和促胰岛素分泌剂被证明有相同的抗高血糖作用。此研究比较了二甲双胍和促胰岛素分泌剂瑞格列奈在非肥胖的2型糖尿病患者的心血管疾病生物标志上的效能。  相似文献   
74.
75.
A baby with unilateral cleft lip, midline cleft palate and hypertelorism developed meningitis in the first 48 h of life. Examination of the nasopharynx showed a soft tissue mass, which was confirmed as a basal encephalocele by computed tomography. There was also congenital hydrocephalus and the corpus callosum was absent. Surgical treatment included repair of the anterior basal skull defect, repair of the lip and palate, and ventriculo-peritoneal shunt. There is currently evidence of developmental delay and right-sided visual impairment due to Morning Glory syndrome. This case demonstrates that basal encephalocele should be considered in any baby with midline facial deformity who develops meningitis.  相似文献   
76.
Two mathematical models to predict the level of parasitaemia after exchange transfusion in severe malaria have been described. One formula, described by Wilkinson and colleagues, calculates the level from the total volume of blood exchanged whereas the other, derived by Van den Ende and colleagues, is recursive and gives estimates of the reduction in parasitaemia after each aliquot of exchange. The accuracies of predictions based on these two formulae were compared using data collected from 20 patients undergoing partial exchange transfusion (40 ml blood/kg body weight). The transfusions led to significant changes in the mean (S.D.) haemoglobin concentrations, which rose from 8.9 (2.4) to 10.1 (1.5) g/dl, and in the median levels of parasitaemia, which fell from 16.5% (interquartile range = 12.8%-28.8%) to 4.5% (interquartile range = 1.2%-9.3%). The median level of post-transfusion parasitaemia predicted by the Van den Ende formula (6.6%, with an interquartile range of 4.5%-10.2%) was similar to that observed, whereas that predicted by the Wilkinson formula (7.2%, with an interquartile range of 5.6%-12.4%) was significantly higher (P = 0.018). However, the median difference between the predictions based on the two formulae was represented by a parasitaemia of only 1.0% (interquartile range = 0.6%-1.85%). Thus, although the Van den Ende formula is more accurate than the Wilkinson, the difference is unlikely to be clinically significant.  相似文献   
77.
BACKGROUND: The LAP-BAND is designed to be an adjustable laparoscopically placed gastric restriction device for the treatment of severe obesity. The purpose of this study was to assess the outcome in patients who had failed to effectively lose weight with this device and were converted to a gastric bypass. METHODS: A retrospective chart review was performed of all LAP-BANDS placed in patients at our institution from March 1996 to June 1998. RESULTS: 36 LAP-BANDS were placed. To date, 18 of 36 (50%) have been removed. Fourteen of 18 were simultaneously converted to a gastric bypass. Indications for conversion included: failed weight loss (5), failed weight loss with esophageal dilatation (5), failed weight loss with leaking band (2), and symptomatic esophageal dilatation (1). Median time to conversion after LAP-BAND placement was 38.2 months. Median follow-up after conversion to gastric bypass was 8.3 months. Nineteen percent excess weight loss occurred after LAP-BAND placement. Forty-three percent excess weight loss occurred after conversion to gastric bypass (P =.025). CONCLUSIONS: In our experience, the LAP-BAND is associated with a high frequency of inadequate weight loss. Conversion to gastric bypass in this subset of patients is technically challenging but results in superior weight loss in a shorter time period.  相似文献   
78.
Pigmented villonodular synovitis (PVNS) is usually a mono-articular disorder. Bilateral symmetrical affection of this disease process is exceptional. A case is reported of a patient with PVNS with bilateral, symmetrical hip joint involvement.  相似文献   
79.
AIM: To examine if the seed extracts of Carica papaya, which showed antispermatogenic/sperm immobilization properties in animal models, could cause human sperm immobilization in vitro. METHODS: Chloroform extract, benzene chromatographic fraction of the chloroform extract, its methanol and ethyl acetate sub-fractions and the isolated compounds from the sub-fractions i.e., ECP 1 & 2 and MCP 1 &2, of the seeds of Carica papaya were used at concentrations of 0.1%, 0.5%, 1% and 2%. Sperm motility was assessed immediately after addition of extracts and every 5 minutes thereafter for 30 minutes. RESULTS: There were dose-dependent spermicidal effects showing an instant fall in the sperm motility to less than 20% at 2% concentration. Isolated compounds ECP 1 & 2 were more effective inducing a motility of less than 10%. Many of the spermatozoa became vibratory on the spot. Total inhibition of motility was observed within 20-25 min at all concentrations of all products. Scanning and transmission electron microscopy revealed deleterious changes in the plasma membrane of the head and mid-piece of spermatozoa. Sperm viability test and the number of abnormal spermatozoa after completion of incubation suggested that the spermatozoa were infertile. The effects were spermicidal but not spermiostatic as revealed by the sperm revival test. CONCLUSION: The results reveal spermicidal activity in vitro of the seed extracts of Carica papaya.  相似文献   
80.
The syntheses of four alpha-aminomethyl phosphonates and their complexation studies with (99m)Tc and (186/188)Re are reported. Complexation conditions were standardized to give maximum yields, which ranged from 90-97%. The yields of complexation were estimated by paper chromatography. The (99m)Tc complexes were stable for more than 4 h, while the (186/188)Re complexes were stable for 3-8 days when stored at 4 degrees C. Biodistribution of these complexes in Wistar rats were carried out, and the uptake in bone and other soft tissue are detailed. Bone uptake of the (99m)Tc complexes varied from 40-60% at 30 min postinjection depending on the ligands. The uptake in soft tissue was minimum with all the complexes. A comparison of the biodistribution studies of the (99m)Tc complexes with that of the well-established radiopharmaceutical (99m)Tc-MDP was carried out for the purpose of evaluating the efficacy of the radiopharmaceutical preparation with the complexes of these ligands. The bone uptake of the (186/188)Re complexes varied from 19-28% corresponding to 1.6-3% per g at 3 h postinjection. The residual activity in both (99m)Tc and (186/188)Re complexes showed renal clearance.  相似文献   
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