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91.
The aim of this study was to compare the survival of 116 patients with breast cancer initially treated at the First Teaching Hospital (FTH) of Norman Bethune University of Medical Sciences located in Changchun, China, from 1986 to 1991 with the survival of 886 patients seen in the “Hipital du Saint-Sacrement” (HSS) located in Quebec City, Canada, from 1987 to 1992. The clinical data were collected from the hospital records at FTH. The vital status for Chinese patients was obtained from letters of follow-up or the records of local police offices. The list of patients treated at HSS and the data for each woman were extracted from computerized data banks. The major variables studied included age at diagnosis, tumor size at pathology (cm), number of lymph nodes involved, breast surgery and adjuvant treatments of breast cancer (chemotherapy, radiotherapy, immuno-therapy). Age at diagnosis was substantially lower among patients with breast cancer seen at FTH compared to those treated at HSS (x) 1 2 =60.95,P<0.0001). The average age at diagnosis for Chinese women was about 10 years less than that for Canadian women. Patients in the two hospitals differed with respect to tumor size at pathology (x 2 2 =6.67,P=0.036). The proportion of patients with tumor size larger than 2.0 cm was larger at FTH (48.3%) than at HSS (41.1%). The mean tumor size at pathology was 3.0 cm (standard deviation =2.1 cm) for patients treated at FTH, but 2.6 cm (standard deviation=1.8 cm) for women treated at HSS (P=0.07). The proportion of women with lymph node involvement was greater at FTH (61.1 % than that at HSS (37.3%) (x 1 2 =16.51,P<0.0001). Surgical treatment of breast cancer varied considerably. In Changchun, radical mastectomy was frequent for any stage of breast cancer patients, but partial mastectomy was never performed. The situation was reversed in Quebec. The five year observed survival was 74.2% (standard error, 0.05) among breast cancer patients seen at FTH compared to 76.0% (standard error, 0.02) among women treated at HSS. After adjustments of confounding factors, there were no significant difference in five year observed survival between the patients treated at the two hospitals (P=0.42).  相似文献   
92.
Summary The effect of obesity and fat distribution on survival of breast cancer patients was studied prospectively in 241 women with a natural menopause who participated in a breast cancer screening project, the DOM-project in Utrecht, The Netherlands. Mean follow-up time was 9.1 years and endpoint of interest was death from breast cancer. Fat distribution was assessed by contrasting groups of subscapular and triceps skinfold thickness.No significant differences in survival time between more obese (Quetelet's index 26 kg/m2) and leaner (Quetelet's index < 26 kg/m2) patients or between patients with central fat distribution and patients with peripheral fat distribution were observed. Analyses were stratified by axillary node status, estrogen receptor status, and way of detection (by first screening or afterwards). Results of the stratified analyses were suggestive of a modifying effect of these factors.The absence of an association between obesity and survival time might be explained by two counteracting mechanisms. On the one hand obesity might be related to impaired survival, due to a tumor growth promoting effect of extra-ovarian estrogens. On the other hand obesity might be related to improved survival in a screened population, because obese patients profit more from screening by earlier detection of tumors than leaner counterparts.  相似文献   
93.
BACKGROUND: A modified milk fat with reduced cholesterol was developed by fractionation technology. OBJECTIVE: The effect of this modified milk fat on the lipoprotein profile of 21 normolipidemic men was compared with that of regular milk fat and nonhydrogenated margarine. DESIGN: A crossover design was used for the administration of the 3 experimental diets, which provided 13240 kJ as 16% protein, 51% carbohydrates, 33-34% lipids, and 21 g fiber/d. The ratio of polyunsaturated to saturated fat was 1.3:1 for the margarine diet and 0.3:1 for the milk-fat diets. The cholesterol content of the modified milk-fat and margarine diets was similar (248 and 254 mg/d, respectively), but was significantly higher (428 mg/d) for the regular milk-fat diet. RESULTS: Modified and regular milk fats did not change plasma total and LDL cholesterol significantly, but margarine did (P < 0.01). Furthermore, modified milk fat maintained initial HDL(2)-cholesterol concentrations, but margarine reduced this variable significantly (P < 0.05). These results can be explained by the lower ratio of polyunsaturated to saturated fat in the modified and regular milk-fat diets than in the margarine diet. Men who ingested modified milk fat had significantly (P < 0.05) lower total and VLDL-triacylglycerol and VLDL-cholesterol concentrations than did those who ingested either regular milk fat or margarine. This may have been, in part, because of the lower intestinal fat absorption with modified milk fat than with regular milk fat and margarine arising from changes in the melting properties of milk fat with fractionation. CONCLUSION: A reduction in plasma triacylglycerol concentrations after the consumption of modified milk fat may prevent the onset of hypertriacylglycerolemia.  相似文献   
94.
The role of interventional radiology for soft tissue sarcomas is only occasionally addressed in the literature. However, different techniques such as embolization, selective chemotherapy, chemoembolization, and acrylic cement osteoplasty can be helpful with the primary tumor, recurrences, and metastases. This article discusses these techniques and their complications in treatment of soft tissue sarcomas.  相似文献   
95.
BACKGROUND: Although cataract surgery is highly developed today, there are still problems such as secondary cataract. In polishing the posterior capsule lens, epithelial cells often remain, causing secondary cataracts. Additionally, there are the problems of tissue heating and endothelial cell loss during phacoemulsification by ultrasound. This could be another field for improvement of cataract surgery by using the waterjet. METHODS: After removing the cornea of freshly enucleated porcine bulbs, we used the water jet from 4 to 12 bar. The hit angel on the capsule varied between 45 degrees and 90 degrees. RESULTS: Rupture of the posterior capsule occurred at a mean of 8.5 bar using the jet at 45 degrees and a mean of 8.6 bar using the jet at 90 degrees. CONCLUSION: The waterjet pressure should not be over 4 bar during polishing of the posterior capsule.  相似文献   
96.
Because the dopamine reuptake inhibitors cocaine and BTCP produce different behavioral effects after repeated administration, we studied whether they could alter each other’s effects by examining the effects of crossing over repeated treatment with cocaine and BTCP on cocaine-induced locomotion. Male C57BL/6 mice were treated repeatedly with cocaine or BTCP during a first phase (days 1–3) and 3 days later, treated repeatedly with the same or the other compound during a second phase (days 7–9), after which they were administered one of several doses of cocaine on the next day. Locomotor activity was assessed after every daily treatment. The results show that 1) cocaine induced sensitization to its locomotor effects, 2) cocaine-induced sensitization was not altered by subsequent repeated treatment with BTCP, 3) initial repeated treatment with BTCP induced apparent cross-tolerance to cocaine, and 4) the initial effects of repeated BTCP were not markedly altered by subsequent repeated treatment with cocaine. The results indicate that the initial effects produced by repeated cocaine or BTCP are enduring and relatively difficult to alter by crossing over repeated treatment with the other compound. Thus, sensitization to the locomotor effects of cocaine in mice appeared to be attenuated by prior repeated treatment with BTCP but not reversed when followed by repeated treatment with BTCP. Received: 11 January 1998/Final version: 17 September 1998  相似文献   
97.
BACKGROUND: Irritable bowel syndrome is one of the most common gastrointestinal disorders, yet no therapy convincingly controls the multiple symptoms of this syndrome. AIM: To compare the efficacy and tolerability of the new 5-HT3-receptor antagonist alosetron and the smooth muscle relaxant mebeverine in a double-blind, multicentre, randomized trial. METHODS: Six hundred and twenty-three nonconstipated females with irritable bowel syndrome were randomized to receive alosetron 1 mg twice daily (n=319) or mebeverine 135 mg three times daily (n=304) for 12 weeks, followed by a 4-week post-treatment period. The primary efficacy end-point was monthly responders for adequate relief of irritable bowel syndrome related abdominal pain and discomfort (defined as patients reporting adequate relief on at least 2 out of 4 weeks). Secondary end-points included assessments of bowel function, including urgency, stool frequency and stool consistency. RESULTS: There were significantly more responders in the alosetron group compared with mebeverine at months 2 and 3 (P < 0.01). Compared with mebeverine, the alosetron group experienced significant decreases in proportion of days with urgency and mean stool frequency, and had firmer stools within 1 week of starting treatment. A similar proportion of patients reported adverse events in the two treatment groups. CONCLUSIONS: In nonconstipated female irritable bowel syndrome patients, alosetron is significantly more effective than mebeverine in improving symptoms.  相似文献   
98.
Nitric oxide (NO) is a short-lived diffusable molecule now believed to participate in multiple physiologic functions in the CNS including neurotransmission and the maintenance of vascular tone. Previously, we reported that cell lines obtained by retroviral immortalization of tissue macrophages (M?;) could be induced to synthesize nitrite (NO), a stable end product of the NO synthetic pathway. We have further characterized the induction and activity of this pathway in a panel of seven microglial clones derived from primary embryonic mouse brain cultures. Like M?;, these clones were found to release high levels of NO-2 in response to recombinant interferon-γ (rIFN-γ) as a priming signal together with either bacterial lipopolysaccharide (LPS) or exogenous recombinant tumor necrosis factor-α (rTNF-α). As previously demonstrated for M?;, phagocytosis of zymosan particles during induction of enzyme activity enhanced subsequent NO production, which is of interest in light of the postulated phagocytic role of microglia within the CNS. Biochemical characterization of enzyme activity in intact microglial clones and in isolated cytosolic fractions indicates that the microglial NO synthase present in these murine cell clones represents the M?;-like isotype. These findings suggest that microglial cells could represent a major source of NO within the CNS.  相似文献   
99.
Jacques Lisfranc was born in Saint-Paul-Jarrest (Loire), France, April 2nd, 1790, the son of a physician. Early in his youth he demonstrated a particular interest and aptitude for the field of medicine as he observed and commented upon his father's ministrations to his patients. He accomplished his preliminary studies at the Lyceum in Lyons and then went to Paris to continue his medical training at the Hôtel-Dieu. It was there that he came under the tutelage of Dupuytren. It was soon said that Lisfranc was at least as worthy as his superior. Later the two men developed a certain animosity toward each other which became manifest rather severely in the medical political arenas of the time. Lisfranc received his doctorate of medicine in 1812 at a time that France was involved in the Napoleonic wars. He was commissioned as a surgeon and distinguished himself in campaigns in Saxony and in France. Following the war he established his practice in Paris. Fortuitously, one day Lisfranc rescued a magistrate who fell from his horse. By this serendipitous meeting Lisfranc was invited to join the faculty of medicine at the Hospital of Pity. He rose rapidly to chief of surgery and developed the reputation of being extremely competent, truly a master surgeon. For over 20 years he was affiliated with that institution and wrote numerous articles on such diverse subjects as shoulder disarticulation, the application of the stethoscope in the diagnosis of fractures, and on diseases of the uterus. In addition, he wrote two books which were well received—one onSurgery at the Hospital of Pity and the other onOperative Medicine. ThisClassics presentation has been selected because it has been generally attributed that Lisfranc was the first person to remove a cancerous tumor from the rectum. The technique involves essentially a transanal approach. As was the custom of the day, the report appears as narrated presumably by one of his assistants. Among the many distinctions Lisfranc achieved, he was founding member and ultimately President of the French Academy of Medicine and Chevalier of the Legion of Honor. Lisfranc developed an enormous clinical practice, and in spite of many physical infirmities he persisted in his surgery until the day of his death, May 12, 1847, at the age of 57.  相似文献   
100.
The process of regulated secretion in PC-12 cells is tightly coupled to calcium entry, which is absolutely dependent on extracellular Ca2+([Ca2+]ex). Tunicamycin treatment of the cells dissociated depolarization-triggered Ca2+ influx from depolarization (high K+)-induced transmitter release into two distinct and independent phases. Deplarization-evoked Ca2+ influx was not affected by tunicamycin treatment (1 microg/ml, 72 h), whereas depolarization-evoked transmitter release was strongly inhibited (> 60%), suggesting at least a two-step process, and the participation of glycosylated protein(s) in the actual fusion/secretion step. Similarly, bradykinin-mediated transmitter release was linearly related to and absolutely dependent on Ca2+ entry, and was inhibited by tunicamycin treatment (> 80%), whereas bradykinin-evoked Ca2+ entry was not impaired, indicating that glycosylated protein(s) are essential for bradykinin-evoked release at a step subsequent to Ca2+ influx. The heavily glycosylated alpha2 subunit of the dihydropyridine-sensitive channel, which was used to monitor tunicamycin inhibition of glycosylation, was not expressed in the tunicamycin-treated cells, as shown by Western blot analysis. This observation allowed us to conclude that the alpha1 subunit of the heteromeric dihydropyridine voltage-sensitive Ca2+ channel, which is responsible for Ca2+ entry, is also fully functional when not assembled with its corresponding alpha2 subunit. The molecular properties of the alpha2 subunit, whose role in the complex structure of the channel is not yet understood, are shown for the first time for the L-type Ca2+ channel of PC-12 cells. Similar to cardiac and skeletal muscle cells, the alpha2 subunit appears to be a glycosylated polypeptide of molecular weight 170 kD and to display a characteristic mobility shift to 140 kD under reducing conditions.  相似文献   
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