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991.
This study describes the influence of isocalorically fed diets (containing different amounts of fat) on tumor incidence and parameters of fat metabolism in female Sprague-Dawley rats. Comparisons are made between rats induced with methylnitrosourea (25 mg/kg body wt) and untreated controls (Group I). The animals received either control diets (3.9% fat by weight, Groups I and II) or fat-enriched diets (10.7%, Group III; 15.6%, Group IV; 21.4%, Group V) over a period of 180 days. At the termination of the experiment, intake of the diet containing 10.7% fat by weight (24% fat per total calories) was associated with the highest tumor incidence. Comparing the different diets, liver lipid concentrations in the individual groups increased with increasing dietary fat, whereas the total lipid in plasma decreased. During the feeding period, total lipid of the liver and plasma, and plasma cholesterol, increased in all groups, but triglycerides of plasma decreased. However, when plasma cholesterol and triglycerides were calculated as a relative amount of total lipid in plasma, cholesterol was found to be significantly decreased in Groups III and IV, and triglycerides were increased in Group III but decreased significantly in Groups I, II, and V at the end of the experiment.  相似文献   
992.
We have compared the effects of acetyl salicylic acid (ASA, aspirin) and choline magnesium trisalicylate (CMT), a non-acetylated salicylate product, on platelet aggregation in human whole blood ex-vivo. Using a whole blood platelet counter, platelet aggregation was quantified by measuring the fall in the number of single platelets at peak aggregation in response to collagen, arachidonic acid (AA), as well as spontaneous aggregation. In double blind and random order, 12 healthy volunteers received, on two separate occasions 10 days apart, a single oral dose of 652 mg ASA or 655 mg CMT. Despite a comparable absorption of salicylic acid from the two drugs, ingestion of ASA resulted in a marked inhibition of platelet aggregation induced by collagen (p less than 0.005), AA (p less than 0.01) and spontaneous aggregation (p less than 0.01), whereas such effects were not observed after CMT ingestion. We suggest that CMT may have therapeutic potential as an alternative to aspirin when inhibition of platelet aggregation can induce bleeding complications.  相似文献   
993.
R B Raynor 《Neurosurgery》1986,19(1):108-110
A patient with Charcot's disease of the lumbar spine presented with weakness of one extremity. Myelographic and x-ray film studies indicated stenosis and compression due to degenerative changes. Although decompression and fusion were considered, computed tomographic scans indicated the wide extent and location of the destructive changes. Nonoperative treatment was elected because of the high risk of fusion failure and instability.  相似文献   
994.
995.
Radiation-induced meningioma. 3 cases   总被引:1,自引:0,他引:1  
During the same year (1984), we have seen 3 cases of meningiomas following radiation therapy of the brain for previously diagnosed tumors. A causal relationship between irradiation and meningioma has been postulated. Nevertheless, the coincidental occurrence in same patient of two different histological lesions is possible. The neoplasms developed after irradiation are of mesenchymal origin; they are fibrosarcomas, osteogenic sarcomas and meningiomas.  相似文献   
996.
High-frequency jet-ventilation (HFJV) was applied to 30 patients undergoing vertical partial surgery of the larynx for carcinoma of the vocal cords. This technique gave good surgical conditions as it interfered little with the air-ducts. It was carried out with a catheter of only 3 mm external diameter; control of ventilation during surgery was adequate, the average PaO2 being 27.9 +/- 5.6 kPa (209.3 +/- 4.2 mmHg) and the average PaCO2 5.4 +/- 1.4 kPa (40.5 +/- 10.5 mmHg). It avoided also the need for a tracheotomy. In the past, anaesthetic techniques were local anaesthesia combined with neuroleptanalgesia, endotracheal intubation or preoperative tracheotomy. None of these methods being satisfactory, our practice now includes first a nasotracheal intubation with an armoured tube at the beginning of the surgical procedure, followed by HFJV during the removal of the vocal cord, the tracheal tube being slightly pulled out. The tracheal tube is then put back in place before the thyroid cartilage is closed. The contra-indications are the same as those of HFJV. There are two types of complications: complications of HFJV itself, and postoperative complications due to the absence of tracheotomy. No accidents were observed. The only incidents seen were related to the lack of tracheotomy: subcutaneous oedema of the neck during the postoperative period in eight patients and moderate tracheobronchial congestion in five patients.  相似文献   
997.
The results of a two-year longitudinal study of the effect that development program incentives have upon family planning in Northeastern Thailand are presented. These incentives, implemented by the Population and Community Development Association, Thailand, included animal raising and agricultural, home industry, and environmental activities. An experimental design including baseline and follow-up surveys supplemented by a continuous monitoring system was utilized to test hypotheses on the family planning impacts of the incentives. Findings indicate that the incentives contributed significantly to the maintenance of high levels of family planning practice through the program period 1982-1984.  相似文献   
998.
999.
We have used a three-dimensional diffusion model of calcium entering the presynaptic nerve terminal through discrete channels to simulate experiments relating transmitter release to presynaptic calcium current. The relationship will be less than linear, or will curve downward, if calcium channels are well separated. It will resemble a power-law function with exponent less than the cooperativity of calcium action if channels are clustered closer together. Large presynaptic depolarizations elicit more release than small depolarizations admitting the same calcium influx. This occurs because large pulses open more channels near each other, with the result that the calcium concentration near release sites is greater, due to overlap of calcium diffusing from adjacent channels.  相似文献   
1000.
Follicular fluids from eight patients with one ovary and from ten patients with two ovaries were investigated for bioactive inhibin, total renin, oestradiol (E2) and progesterone (P4) concentrations. Four follicular fluids were pooled per patient before assessment. All women had been stimulated similarly using a protocol including a GnRH agonist, HMG and HCG. Renin levels were significantly lower and P4 significantly higher in pools of follicular fluid from patients with one ovary, whereas inhibin and E2 concentrations were similar in both patient groups. A significant negative correlation was found in the pools of follicular fluid between inhibin and E2 in both groups. These results suggest a role for inhibin and renin in the paracrine and autocrine control of stimulated follicular development.  相似文献   
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