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991.
Vitamin requirements for the treatment of hyperhomocysteinemia in humans   总被引:1,自引:0,他引:1  
We have previously shown that a modest vitamin supplement containing folic acid, vitamin B-12 and vitamin B-6 is effective in reducing elevated plasma homocysteine concentrations. The effect of supplementation of the individual vitamins on moderate hyperhomocysteinemia has now been investigated in a placebo-controlled study. One hundred men with hyperhomocysteinemia were randomly assigned to five groups and treated with a daily dose of placebo, folic acid (0.65 mg), vitamin B-12 (0.4 mg), vitamin B-6 (10 mg) or a combination of the three vitamins for 6 wk. Folic acid supplementation reduced plasma homocysteine concentrations by 41.7% (P < 0.001), whereas the daily vitamin B-12 supplement lowered homocysteine concentrations by 14.8% (P < 0.01). The daily pyridoxine dose did not reduce significantly plasma homocysteine concentrations. The combination of the three vitamins reduced circulating homocysteine concentrations by 49.8%, which was not significantly different (P = 0.48) from the reduction achieved by folate supplementation alone. Our results indicate that folate deficiency may be an important cause of hyperhomocysteinemia in the general population.  相似文献   
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PURPOSE: We describe the differential points in the diagnosis of the combination of renal dysgenesis, Gartner's duct cyst and ipsilateral müllerian duct obstruction. Various imaging studies and urological procedures were performed. We report our experience in detecting these anomalies in 10 girls and review the literature. MATERIALS AND METHODS: Ten girls, 7 to 13 years old, with this combination of anomalies were identified in the last 10 years. Imaging studies as well as urological procedures were selectively performed, especially at puberty following menarche. Patients received long-term followup with ultrasound. RESULTS: Cystic dilation of Gartner's duct protruded into the bladder and presented as a ureterocele in 5 patients and posterior to the bladder in 5. Surgical removal of a partial portion of a Gartner's duct cyst was performed in 5 patients for alleviation of urinary symptoms. Unilateral müllerian duct obstruction was demonstrated in all 10 patients. Excision of the vaginal septum was performed in 6 patients for relief of genital obstruction. CONCLUSIONS: When cystic dilatation of the pelvis, especially a ureterocele-like cyst without ureteral dilatation, is found in girls with ipsilateral renal dysgenesis, the possibility of a Gartner's duct cyst should be considered. For early detection and treatment of unilateral obstruction of duplicated müllerian ducts pelvic sonography should be performed at puberty, especially just after menarche, in girls with renal dysgenesis and ipsilateral Gartner's duct cyst.  相似文献   
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The purpose of this work is to compare bladder and rectal dose rates in brachytherapy for carcinoma of the cervix using two different dosimetry systems: traditional orthogonal radiograph-based dosimetry vs. computed axial tomography tandem and ovoids (CATTO) dosimetry. Twenty-two patients with carcinoma of the uterine cervix received the brachytherapy component of their radiotherapy with a computed-tomography compatible Fletcher-Suit-Delclos device. A total of 27 implants were performed. The average maximum bladder dose (Bmax) for the implants was 85.8 cGy/hr using the CATTO system as compared to 42.6 cGy/hr using traditional dosimetry, (P < 0.005). The average maximum rectal dose (R.) using the CATTO system was 59.2 cGy/hr as compared with 46.3 cGy/hr using the traditional system (P < 0.05). The traditional methods for choosing points to determine bladder and rectal dose rates underestimated the true Bmax in all cases and the R. in most. Based on the complication rates published in the literature, it is likely that the maximum tolerance dose of both the rectum and bladder, but especially the bladder, is higher than previously thought.  相似文献   
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Rats were meal-fed semipurified diets containing a low (0.8 g/MJ) and a high (9.6 g/MJ) amount of resistant starch (RS) or various amounts of RS (0.8 to 9.6 g/MJ) and guar gum (0 to 8.8 g/MJ). In one experiment, rats were fed the low and high RS diets in three dietary regimens (ad libitum consuming, 12 h ad libitum/12 h food deprived, and meal fed). Effects of RS and guar gum on serum postprandial and postabsorptive concentrations of total cholesterol (TC) and triacylglycerol (TAG), growth, hydrogen excretion, tissue weights and contents of small intestine and cecum, and pH of cecal contents were investigated. In addition, effects of RS on food intake, de novo hepatic synthesis of fatty acids and neutral sterols, and on lipoprotein lipase activity and weight of epididymal fat pads were investigated. Compared with feeding the low RS diet, the high RS diet reduced the serum TC and TAG concentrations, with these effects observed after 1 and 2 wk of feeding, respectively. The dietary regimen did not influence the effect of RS on the serum TC and TAG concentrations, but it did affect the serum TAG concentration. Resistant starch had no effect on the hepatic synthesis of fatty acids and neutral sterols or on the lipoprotein lipase activity in epididymal fat pads. Guar gum also reduced the serum TC concentration, but it had no effect on serum TAG concentration. The tissue weights and contents of small intestine and cecum as well as hydrogen excretion increased with increasing amounts of dietary RS and guar gum, whereas the pH of cecal contents decreased. No effects of RS on food intake and total body weight gain were found, whereas guar gum decreased weight gain. Feeding the high RS diet also led to a lower weight of the epididymal fat pads. We conclude that dietary RS can reduce serum TC and TAG concentrations and fat accretion.  相似文献   
1000.
BACKGROUND: Despite general recommendations, patch test readings are still sometimes terminated at day 2. OBJECTIVE: The consequences of failure to read patch tests after day 2 and the influence of exposure time to the patches is quantified. METHODS: Patch test data from 9,946 patients with at least one positive reaction at day 2 or later and readings at both days 2 and 3 (from 21,062 patients tested between January 1, 1990, and December 31, 1993) collected by the Information Network of Departments of Dermatology in Germany were analyzed. RESULTS: Comparing results at days 2 and 3, 34.5% of all positive reactions appeared at day 3 only, whereas 8.3% initially judged (weakly) positive were not considered allergic at day 3. Some standard allergens showed specific patterns. Additional positive reactions and an increasing percentage of diminishing reactions can be observed at day 4 (compared with day 3). CONCLUSION: The importance of late reading(s) is emphasized by the proportion of potentially false judgments based on readings at day 2 only.  相似文献   
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