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71.
AI Necha? VM Sitenko KV Novikov VV Stukalov VT Drobot 《Canadian Metallurgical Quarterly》1980,125(10):27-35
Concrements were found in the ducts of 172 patients subjected to secondary surgical interventions on bile ducts. The detailed analysis of the data failed to answer the question whether the stones could be formed immediately in the ducts without such conditions as a mechanical obstacle for the outflow of bile, the presence of foreign bodies and a big stump of the cystic duct. Such a formation of stones can take place in very few cases. The authors have shown that control cholangiography and especially choledochoscopy can reduce the danger to leave the stones in the ducts, but does not eliminate the danger completely. Nevertheless they think that now it is possible to lessen the indications for biliodigestive anastomoses in choledocholithiasis since the retained stones can be revealed within the first days after surgery and, as a rule, removed with instruments or by other methods using the drainage left in the ducts. 相似文献
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73.
VM Figueredo 《Canadian Metallurgical Quarterly》1997,101(2):165-8, 171-2, 175-6
Alcohol abuse is a substantial public health problem, resulting in staggering financial costs and other burdens. Prolonged alcohol abuse leads to cardiomyopathy in a minority of alcohol abusers, but because alcoholism is so widespread, alcohol is the major cause of nonischemic cardiomyopathy in Western society. In contrast, substantial evidence now suggests that moderate alcohol consumption has cardioprotective effects. It not only reduces the incidence of fatal ischemic heart disease, but it improves outcome in patients who have other risks for coronary events and go on to have myocardial infarctions. Therefore, physicians' recommendations about alcohol consumption should be as individualized as their patients. 相似文献
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An extensive study of road traffic accident cases occurring within eastern suburban Calcutta during April 1992 to March 1993 was done. Of which 276 fatal cases having minimum medical aids were taken into consideration to avoid erroneous interpretation. Male pedestrians of age group of 50 years and above were mostly involved during the time period of 5 A.M. to 12 Noon. Fatal Accidents mostly occurred during winter and on the broader roads (Highways) and in majority of cases victims were at fault. 相似文献
76.
J Qing VM Maher H Tran WS Argraves RW Dunstan JJ McCormick 《Canadian Metallurgical Quarterly》1997,15(18):2159-2168
Using differential display, we identified an mRNA that is markedly down-regulated in cell line 6A/SB1, derived from a fibrosarcoma formed in an athymic mouse following injection of carcinogen-transformed MSU-1.1 cells. The nontumorigenic parental cell strain, MSU-1.1, expresses high levels of this mRNA. Sequencing of the corresponding cDNA fragment revealed that it corresponded to an expressed sequence tag, which ultimately led to its identification as the fibulin-1D gene. Fibulin-1 is a cysteine-rich, calcium-binding extracellular matrix and plasma protein, which has four isoforms, A-D, derived from alternative splicing. Northern and Western blotting analysis of 16 cell lines established from tumors formed in athymic mice by MSU-1.1-derived cell strains independently transformed in culture showed that 44% exhibited low level or lack of expression of fibulin-1D mRNA and protein. In a similar analysis of 15 malignant cell lines derived from patients, 80% showed low level or no expression. To study the role of fibulin-1D in transformation, we transfected 6A/SB1 cells and a human fibrosarcoma-derived cell line (SHAC) with a fibulin-1D cDNA expression construct. Transfectants displaying high levels of fibulin-1D were isolated and characterized. Elevated expression of fibulin-1D led to reduced ability to form colonies in soft agar and reduced invasive potential as tested in a matrigel in vitro invasion assay. Furthermore, expression of fibulin-1D resulted in a markedly extended latency in tumor formation in athymic mice. These results indicate that low expression of fibulin-1D plays a role in tumor formation and invasion. 相似文献
77.
Chronic action of different xenobiotics which form a part of condensed hydrogen sulphide-containing gas causes substantial changes in the activity of xenobiotic metabolic enzymes, which is suggestive of the damaged hepatic microsomal monooxygenase system. As the rate of biotransformation becomes higher, there are increases in the activity of microsomal monooxygenases and in the generation of active oxygen forms and hydrogen peroxide, by impairing antiradical and antiperoxide mechanisms. The experimentally used concentration of substances as constituents of condensed gas corresponds to the maximum acceptable air concentration of in the working area of gas-refining plants, but the functional features of the body's detoxifying system--the hepatic monooxygenase system should be taken into account while developing preventive measures of occupational diseases. 相似文献
78.
VM Petrov 《Canadian Metallurgical Quarterly》1998,32(5):46-51
The concept of acceptable risk is considered in the context of the system of medical support to space missions. Risk is defined as probability of cosmonaut's health and life deterioration as a result of spaceflight impacts on the human body. Mathematical formulas giving the general characteristic of the relations among risk components, total risk, and human survivability in flight and after its end. The earlier published quantitative recommendations for these parameters are inserted as illustration. 相似文献
79.
VM Figueredo 《Canadian Metallurgical Quarterly》1996,99(4):207-214
The prognosis for a patient who has survived an acute myocardial infarction depends on three general prognostic factors: (1) residual left ventricular function, (2) remaining viable myocardium at risk (residual ischemia), and (3) presence of substrate for the development of malignant arrhythmias. Multiple clinical and historical factors predict the presence of one or more of these prognostic indicators. Electrocardiographic exercise treadmill testing needs to be done in all patients with uncomplicated infarctions. Guidelines of the American College of Cardiology/American Heart Association Task Force are recommended for risk stratification in most patients after acute myocardial infarction. 相似文献
80.
VM Reddy DB McElhinney HA Rajasinghe JR Liddicoat K Hendricks-Munoz JR Fineman FL Hanley 《Canadian Metallurgical Quarterly》1999,117(2):343-351
BACKGROUND: Fetal cardiac bypass causes placental dysfunction, characterized by increased placental vascular resistance, decreased placental blood flow, hypoxia, and acidosis. Vasoactive factors produced by the vascular endothelium, such as nitric oxide and endothelin 1, are important regulators of placental vascular tone and may contribute to this placental dysfunction. METHODS: To investigate the role of the vascular endothelium in placental dysfunction related to fetal cardiac bypass, we studied 3 groups of fetal sheep. In the first group (n = 7) we determined placental hemodynamic responses before and after bypass to an endothelium-dependent vasodilator (acetylcholine), an endothelium-independent vasodilator (nitroprusside), and endothelin 1. In the second group (n = 8) a nonspecific endothelin receptor blocker (PD 145065) was administered and placental hemodynamic values were measured before and after bypass. In the third group (n = 5) endothelin 1 levels were measured before and after bypass. RESULTS: Before fetal cardiac bypass exogenous endothelin 1 decreased placental blood flow by 9% and increased placental resistance by 9%. After bypass endothelin 1 decreased placental flow by 47% and increased resistance by 106%. There was also a significant attenuation of the placental vascular relaxation response to acetylcholine after bypass, whereas the response to nitroprusside was not significantly altered. In fetuses that received the PD 145065, placental vascular resistance increased significantly less than in control fetuses (28% versus 62%). Similarly, placental blood flow decreased significantly more (from 6. 3 +/- 3.1 to 28.3 +/- 10.4 pg/mL; P =.01) in control fetuses than in fetuses receiving PD 145065 (33% versus 20%). Umbilical venous endothelin 1 levels increased significantly in fetuses exposed to fetal bypass but did not change in control fetuses. CONCLUSIONS: The basal endothelial regulatory mechanisms of placental vascular tone were deranged after fetal cardiac bypass. Endothelin receptor blockade, which substantially reduced postbypass placental dysfunction, and other interventions aimed at preserving endothelial function may be effective means of optimizing fetal outcome after cardiac bypass. 相似文献