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71.
目的:研究唐古特大黄提取物不同成分的泻下作用。方法:采用炭末推进方法、酚红排空方法进行肠推进实验,观察大黄提取物各成分(15 g·kg-1)对小鼠小肠推进和肠水分吸收、大鼠大肠运动的影响。结果:唐古特大黄提取物不同成分与对照组相比,对小鼠小肠推进和肠水分吸收、大肠推进作用均有显著性差异(P<0.01);与大黄水煎液、醇提液相比,泻下活性存在一些差异。结论:唐古特大黄提取物不同成分均有显著的泻下作用,但与大黄水煎液和醇提液相比有一些差异。  相似文献   
72.
Decellularized human dermis as a potentially ideal scaffold for dermal substitution in severe burns was examined in a two‐staged animal experiment. In an initial step, an in vitro generated composite graft consisting of human keratinocytes and decellularized dermis (AlloDerm®) was transplanted onto nude mice in a short‐term trial (n = 20, 14 days). Subsequently, a combined one‐step grafting of full thickness wounds with both decellularized dermis (in part preincubated with fibroblasts) and cultivated autologous keratinocytes as a cell suspension in fibrin glue was done in a long‐term porcine animal model (n = 10, 6 months). In both series, macroscopic wound healing was evaluated by planimetry. Histological investigations included morphological as well as immunohistochemical parameters. The short‐term study showed both successful integration of the composite grafts and reduction of wound contraction compared with the control group (epithelial grafts). The long‐term porcine study displayed reduced myofibroblast formation and contraction in the wounds that had been treated with fibroblast‐preincubated dermis. After 4 weeks, a decline of the structural integrity of the dermal matrix could be noticed. The utility of decellularized dermis as template for both dermal reconstitution and keratinocyte delivery vehicle was shown. The closure of full thickness wounds by a single‐step combination of an autologous keratinocyte fibrin sealant suspension and acellular dermis in a pig animal model could be shown. Incorporation of fibroblasts led to reduced wound contraction but could not prevent the loss of dermal integrity. The engineered ‘skin’ remained viable and stable over a period of 6 months.  相似文献   
73.
A case of emphysematous pyelonephritis is presented and a review of literatures is made. A 67-years-old woman with diabetes mellitus, complained of severe left flank pain and high fever and was referred from the department of gastroenterology. A computed tomography film demonstrated gas in the left renal parenchyma and a diagnosis of emphysematous pyelonephritis was made. She was in a state of shock and died after 4 days of conservative treatment. Emphysematous pyelonephritis is a rare, life-threatening disorder and 85 cases in the world have been reported to date. Our case is the 18th one in Japan. Its etiology, symptomatology, treatment and prognosis are discussed.  相似文献   
74.
Twenty-six patients (4 months to 6 years old) with achondroplasia complicated by sleep apnea and/or other neurologic manifestations underwent plain computed tomography (CT) of the craniocervical junction; six also underwent CT myelography. For objectification, multiplanar reconstruction was used to complement axial plane measurements by providing coronal and sagittal measurements; multiplanar reconstruction also improved perception of the longitudinal relationships between the brain stem and subarachnoid space. A narrow subarachnoid space was found in all 26 patients; marked cord compression was present in nine, six of whom underwent CT myelography. These six had marked focal obliteration of the subarachnoid space on both plain CT and CT myelography. Since the subarachnoid space immediately above and below the craniocervical junction is normally capacious, when marked constriction was present, no additional information could have been gained from CT myelography. Thus, plain CT was shown to be sufficient for surgical planning (suboccipital decompression) in nine patients with cord compression due to achondroplasia.  相似文献   
75.
76.
Medical schools put little emphasis upon education on public health, even though public health has played an important role in this century. One way to harness its benefit in order to improve global health in the 21st century is to globally share lectures on public health through the Internet. We have developed the Supercourse comprising of web-based learning modules on epidemiology in a standardized format with the size of each web page less than 10 kilobytes. A cross-sectional observational study was conducted to investigate the association of the perception of the access speed to Web-based lectures by teachers with their perception of lecture quality. There were 223 teachers who rated the lectures: 72% were from North America or Western Europe, 40% had taught epidemiology, and 14% reported that the speed of access was slow. Odds ratio of above-average rating among those who reported that the speed of access was fast relative to those who reported that the speed of access was slow was 4.25 (2.03-8.91; P = 0.001). The odds ratios were similar and significant after taking into account several other factors, including the variation of rating across lectures, region, and experiences in teaching epidemiology. The results indicate that the perception of the quality of Web-based lectures is related to the speed of access to a web page. The speed of access may be as important, if not more important, as the content itself. This suggests that, to share educational materials on the Web globally for teachers, one must consider not only the content, but also how people at local sites gain access to the Internet.  相似文献   
77.
Serial pulmonary imaging has proved to be effective in the evaluation of patients undergoing total joint arthroplasty. A clinical dilemma arises in asymptomatic patients whose postoperative pulmonary images differ from the preoperative images. The authors prospectively evaluated 403 patients with serial imaging to determine the significance of changed postoperative images in asymptomatic patients undergoing total hip or knee arthroplasty. Twenty-two (5.5%) patients had significant changes on postoperative images. Seventeen were asymptomatic; all but one underwent pulmonary angiography. Documented pulmonary emboli were demonstrated in 100% of patients whose postoperative images changed to indicate a high probability of pulmonary embolism, 71% whose images changed to a moderate probability, and 0% whose images changed to indeterminate probability. Overall, pulmonary emboli occurred in 76% of all asymptomatic patients with significantly change postoperative images. Asymptomatic pulmonary embolism is a significant occurrence after total hip or knee repair, and a changed lung scan with appropriate clinical evaluation is an accurate indicator of pulmonary emboli in asymptomatic postarthroplasty patients.  相似文献   
78.
Morton  JD; Harrison  LB; Peschel  RE 《Radiology》1986,159(1):249-252
Of 179 patients with stage B or C adenocarcinoma of the prostate, 106 underwent iodine-125 seed-implant therapy (I-125 SI) and 73 received external-beam radiation therapy (EB). A retrospective analysis determined disease-free survival rate, local tumor control, and complication rate for each treatment group. The 5-year disease-free survival rates for SI-treated patients were 75% for stage B and 30% for stage C groups. Corresponding rates for EB-treated patients were 75% and 40%, respectively. The rate of local tumor control for stage B patients was 85% for SI-treated and 88% for EB-treated patients. The corresponding rates for stage C tumors were 75% for SI-treated and 92% for EB-treated patients. The rate of long-term complications in each group was approximately 10%. For stage B cancer of the prostate, I-125 SI treatment is an acceptable alternative to EB therapy; our data are inconclusive regarding stage C treatment, but EB therapy is preferred.  相似文献   
79.
Dynamic CT scans of the kidney were conducted in 57 persons with varied renal function. The results of dynamic CT were used to obtain time-density curves for renal cortex, medulla and aorta. Various parameters were calculated from these time-density curves. Among them, CA ratio, the ratio of the area under the renal cortex curve to the area under the aortic curve, showed the best correlation with creatinine clearance. With these parameters, dynamic CT studies are believed to be useful in evaluating renal function.  相似文献   
80.
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