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991.
K Orth  E Sch?lzel  H G Beger 《Der Chirurg》1992,63(5):421-425
Cryotherapy was applied to 182 rectal cancer patients in the Department of General Surgery, University of Ulm, between 4/1982 and 4/1991. Recipients of this tumor freezing therapy were patients whose general condition was bad, patients with an advanced inoperable carcinoma, patients with tumor recurrence and patients refusing operation. Rectal carcinomas, mostly in an advanced stage, were usually freezed several times. Only 4 patients with general inoperability reached the survival time margin of 5 years. In 18 patients local tumor destruction was possible by application of cryotherapy. In 80% of cases disagreeable tumor symptoms like tenesma, mucous discharge and oozing hemorrhages could be reduced or completely removed. Perianal pain and intense tumor bleeding could be relieved temporarily or definitely in only 50% of patients. An artificial anus could be avoided in 80% of cases by local tumor destruction/reduction or arrest of tumor growth. The mean survival time of patients with tumor recidivation was 11 months after onset of the recurrence. Tumor progression, incontinence and iatrogenic rectal perforation made an artificial anus necessary in 14 patients.  相似文献   
992.
胆囊癌的诊断和治疗   总被引:3,自引:0,他引:3  
陈国庆  袭正军 《上海医学》1997,20(6):328-330
  相似文献   
993.
Y Chen  J M Potter 《Clinical chemistry》1992,38(12):2426-2430
We compared fluorescence polarization immunoassay (FPIA, x) and HPLC (y) for measuring monoethylglycinexylidide (MEGX) concentrations in 119 serum samples from 61 liver-transplant donors and recipients. The correlation between the two methods was y = 1.48 micrograms/L + 0.8x (r = 0.89). The bias (mean difference) was 12 micrograms/L (0.055 mumol/L) through the MEGX concentration range measured (0-250 micrograms/L, 0-1.136 mumol/L). We observed a major difference between the two methods in samples from four recipients and one donor. Cross-reactivity in FPIA with lignocaine and two of its metabolites (glycinexylidide and 2,6-xylidine) was < 3%. Samples with high bilirubin concentrations (> 200 mumol/L) required dilution before assay of MEGX by FPIA. Although there was an increase in apparent MEGX concentrations in some samples with increased bilirubin concentrations, the relationship was not constant. Increased plasma concentrations of cholesterol and triglyceride resulted in relatively small increases in apparent MEGX concentrations.  相似文献   
994.
Exposure of cultured human glomerular mesangial cells (GMC) to normal human serum and an activator of the complement system results in rapid uptake of the terminal complement proteins C5b-9 by the cells. This 'innocent bystander' complement attack, however, does not result in cell killing, but in the stimulation of the GMC to release prostaglandin E (PGE), interleukin 1 (Il-1) and tumor necrosis factor (TNF). Endogenously synthesized Il-1 in turn activates PGE release, indicating that the C5b-9 attack initiates an autocrine feedback stimulation. Together with the fact that C5b-9 is found in many forms of glomerulonephritis, the data point to a role of the terminal complement proteins in the initiation and perpetuation of an inflammatory response.  相似文献   
995.
《口腔颌面外科学》是一门以研究口腔器官如牙、牙槽骨、唇、腭、舌、咽等面部软组织、颌骨诸骨如上颌骨、下颌骨、颧骨等,颞下颌关节、唾液腺以及颈部某些疾病的防治为主要内容的学科。是口腔医学的重要组成部分。在国家口腔执业医师资格考试内容中占有较大比例,约为22%-25%。如何准备这门学科的考试以顺利取得口腔执业医师资格?  相似文献   
996.
997.
Q X Chen  R K Wong 《Brain research》1992,582(2):232-236
Tetraethylammonium (TEA) effects on K currents were examined on either side of the membrane of hippocampal CA1 neurons by means of whole-cell voltage-clamp recording and intracellular perfusion. Recording media contained ion channel blockers to allow the selective activation of voltage-dependent K currents which consisted of a rapidly decaying component (A-current) and a delayed component. Voltage protocols were applied to separate the A-current from the delayed component. Results show that 10 mM extracellular TEA suppressed 50 +/- 11% (S.D., n = 4) of the delayed current at different levels of depolarization but had little effect on the A-current. In contrast 10 mM TEA applied by intracellular perfusion suppressed the A-current by 42 +/- 10% (S.D., n = 4) in addition to inhibiting the delayed currently 55 +/- 15% (S.D., n = 4). Both the intracellular and extracellular actions of TEA on K currents showed no voltage- nor time-dependency. The results suggest that voltage-dependent transient current (A-current) is mediated through a separate group of ionic channels distinct from those that sustained the delayed current. Furthermore, the asymmetrical effects of intracellular and extracellular TEA on the transient current are similar to those described for the A-current in molluscan neurons. This observation supports the notion that the structure of the ion channel mediating the A-current is closely conserved across different species.  相似文献   
998.
The normal leakage flow in modern technical heart valve prostheses can be visualized by color-coded Doppler-echocardiography, provided that an adequate ultrasonic image quality can be achieved. Sometimes it may be difficult, however, to distinguish such a normal leakage flow from pathological regurgitation. We therefore mounted new specimens of five different types of prostheses (Bj?rk-Shiley monostrut, Medtronic-Hall, Omnicarbon, Saint Jude Medical, Duromedics) into an invitro model, where the leakage flows could directly be visualized as emerging water jets. When the system was completely filled, the jets could also be registered by two-dimensional Doppler-echocardiography. For each valve, characteristic patterns for the localization of the principal jets were found. Besides the relative broad central jet in the Medtronic-Hall valve, all other jets arose mainly at the ring. They were detected at the hinges or the basis of the larger struts, respectively, and with asymmetrical mono-disc valves at the side of the smaller opening. The length and the orientation of the jets were found to change significantly with minimal variations of the position of the closing discs. This variability could be confirmed, when in a separate model the overall leakage flows were repeatedly measured. For patient examinations it seems useful to refer mainly to the localization of the jet origins. The comparison with reference values of jet-dimensions in Doppler images will rarely enable the examiner to distinguish between normal and pathological jets.  相似文献   
999.
川芎嗪对脑外伤患者血栓素、前列腺环素及颅内压的影响   总被引:6,自引:0,他引:6  
28例重度脑外伤患者分为川药嗪治疗组和一般治疗对照组,两组病人均于用药前和用药后3小时测定血浆和脑室内脑脊液(VCSF)中血栓素代谢产物(TXB_2)前列腺环素代谢产物6—酮—PGF_(la)(6KP)和颅内压。结果表明:两组治疗前血浆、VCSF中TXB_2及T/K均明显高于正常献血员对照组,川芎嗪能降低脑外伤患者血浆、VCSF中TXB_2及T/K值,对颅内压则无明显影响。提示川芎嗪能抑制脑外伤对血小板的激活、纠正循环血中TXA_2—PGI_2平衡失调,从而改善脑微循环。  相似文献   
1000.
The right gastroepiploic artery (GEA) was used as a pedicled conduit for direct coronary artery revascularization in 20 patients presenting with more or less exhausted saphenous vein resources. The early angiographic patency of the GEA conduit appears to be satisfactory when it is connected to the right coronary artery system. A distinct disadvantage of GEA grafting is the necessity to enter the abdominal cavity, which may lead to probably rare and as yet unrecognized morbidity. Future abdominal surgery may injure the GEA conduit unless its topographic relations to the prepyloric antrum, liver and diaphragm are properly recognized. The surgeon must then be prepared to encounter antegastric, retrogastric, antehepatic, transhepatic and retrohepatic routes of the redirected intraabdominal artery. The present paper addresses this problem. Preoperative angiography of the celiac trunk and superior mesenteric artery may be helpful in decision-making when a patient reports or records show that a graft has been harvested from the abdominal cavity.  相似文献   
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