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41.
42.
BACKGROUND. Iron can induce lipid peroxidation in vitro and in vivo in humans and has promoted ischemic myocardial injury in experimental animals. We tested the hypothesis that high serum ferritin concentration and high dietary iron intake are associated with an excess risk of acute myocardial infarction. METHODS AND RESULTS. Randomly selected men (n = 1,931), aged 42, 48, 54, or 60 years, who had no symptomatic coronary heart disease at entry, were examined in the Kuopio Ischaemic Heart Disease Risk Factor Study (KIHD) in Eastern Finland between 1984 and 1989. Fifty-one of these men experienced an acute myocardial infarction during an average follow-up of 3 years. On the basis of a Cox proportional hazards model adjusting for age, examination year, cigarette pack-years, ischemic ECG in exercise test, maximal oxygen uptake, systolic blood pressure, blood glucose, serum copper, blood leukocyte count, and serum high density lipoprotein cholesterol, apolipoprotein B, and triglyceride concentrations, men with serum ferritin greater than or equal to 200 micrograms/l had a 2.2-fold (95% CI, 1.2-4.0; p less than 0.01) risk factor-adjusted risk of acute myocardial infarction compared with men with a lower serum ferritin. An elevated serum ferritin was a strong risk factor for acute myocardial infarction in all multivariate models. This association was stronger in men with serum low density lipoprotein cholesterol concentration of 5.0 mmol/l (193 mg/dl) or more than in others. Also, dietary iron intake had a significant association with the disease risk in a Cox model with the same covariates. CONCLUSIONS. Our data suggest that a high stored iron level, as assessed by elevated serum ferritin concentration, is a risk factor for coronary heart disease.  相似文献   
43.
AIM: To characterise the effect of energy restriction (ER) on liver lipid and primary metabolite profile by using metabolomic approach. We also investigated whether the effect of energy restriction can be further enhanced by modification of dietary protein source and calcium. METHODS: Liver metabolomic profile of lean and obese C57BI/6J mice (n = 10/group) were compared with two groups of weight-reduced mice. ER was performed on control diet and whey protein-based high-calcium diet (whey + Ca). The metabolomic analyses were performed using the UPLC/MS based lipidomic platform and the HPLC/MS/MS based primary metabolite platform.
RESULTS: ER on both diets significantly reduced hepatic lipid accumulation and lipid droplet size, while only whey + Ca diet significantly decreased blood glucose (P 〈 0.001) and serum insulin (P 〈 0.01). In hepatic lipid species the biggest reduction was in the level of triacylglycerols and cerarnides while the level of cholesterol esters was significantly increased during ER. Interestingly, diacylglycerol to phospholipid ratio, an indicator of relative amount of diabetogenic diglyceride species, was increased in the control ER group, but decreased in the whey + Ca ER group (P 〈 0.001, vs obese). ER on whey + Ca diet also totally reversed the obesity induced increase in the relative level of lipotoxic cerarnides (P 〈 0.001, vs obese; P 〉 0.05, vs lean). These changes were accompanied with up-regulated TCA cycle and pentose phosphate pathway rnetabolites.
CONCLUSION: ER-induced changes on hepatic rnetabolornic profile can be significantly affected by dietary protein source. The therapeutic potential of whey protein and calcium should be further studied.  相似文献   
44.
BACKGROUND: Galacto-oligosaccharides potentially attenuate colonic inflammation by two mechanisms: through beneficial effects on intestinal microflora and by increasing the colonic short-chain fatty acid concentration. The purpose of this study was to investigate the effects of galacto-oligosaccharides on the development of inflammation and on the growth of bifidobacteria in trinitrobenzene sulphonic acid (TNBS)-induced colitis, a model that has been shown to benefit from short-chain fatty acid administration and to be associated with alterations in the colonic microflora. Methods: Rats were given daily either whey-derived or lactose-derived galacto-oligosaccharides (4 g kg(-1) day(-1), p.o.); starting 10 days before colitis induction, or dexamethasone (2 mg kg(-1) day(-1), s.c., a positive control), starting at colitis induction. Colon wet weight, macroscopic damage and myeloperoxidase activity were assessed 72 h after the induction of colitis. Faecal bifidobacteria were counted at the beginning of the study, and immediately before and 72 h after colitis induction. Results: Galacto-oligosaccharides increased the colonic levels of bifidobacteria but also the levels of other bacterial species. Neither whey-derived nor lactose-derived galacto-oligosaccharides reduced the severity of inflammation. Conclusions: Galacto-oligosaccharides are able to modify gut microflora in severe TNBS-induced colitis, but unable to attenuate the inflammation.  相似文献   
45.
OBJECTIVE: To assess the validity of the recently developed American College of Rheumatology (ACR) nomenclature for neuropsychiatric systemic lupus erythematosus (NPSLE). METHODS: We conducted a cross-sectional, population-based study covering an area with 440,000 people. A total of 46 patients aged 16 to 65 years fulfilled the criteria for a definite diagnosis of SLE. One control for each patient matched by age, sex, education, and place of residence was randomly identified from the population register. All patients and controls underwent a clinical neurologic examination and neuropsychological testing. The data were analyzed using conditional logistic regression methods. RESULTS: Forty-two patients (91%) and 25 controls (56%) fulfilled at least one of the ACR NPSLE criteria, which gave an odds ratio (OR) of 9.5 (95% confidence interval [CI] 2.2-40.8) but low specificity (0.46). Cognitive dysfunction was the most common syndrome detected in 37 patients (80%). A revised set of 16 criteria excluding the syndromes without evidence for neuronal damage resulted in improved specificity (OR 7.0, 95% CI 2.1-23.5, specificity 0.93). CONCLUSION: The proposed 19 ACR criteria did not differentiate SLE patients from controls, nor NPSLE patients from other SLE patients. The revised NPSLE criteria proposed by us performed well in our population but should be evaluated in a larger patient population.  相似文献   
46.
BACKGROUND: Lactobacillus helveticus-fermented milk has been shown to increase calcium absorption compared to ordinary sour milk. In the present study the possible effect of L. helveticus-fermented milk on bone was studied in growing rats. METHODS: Spontaneously hypertensive male rats, which develop an osteoporotic bone disorder with age, were randomized into 5 groups (n = 10) receiving milk fermented with L. helveticus 16H and, as reference drinks, milk fermented with L. helveticus and Saccharomyces cerevisiae, sour milk, skim milk or water, for 14 weeks. After the intervention bone mineral density and bone mineral content were measured by dual-energy X-ray absorptiometry. The femur weight, length and volume were measured before ashing. From the ashes the weight and mineral content were assessed. RESULTS: As the body weight gain differed significantly between the groups, the results were related to the body weight. The L. helveticus-fermented milk intervention significantly increased the bone mineral density and bone mineral content compared to the sour milk, skim milk and water interventions. The mean values of the bone mineral density and bone mineral content were higher in the L. helveticus-fermented milk group compared to the Saccharomyces-fermented milk group but the difference was not statistically significant. CONCLUSION: L. helveticus-fermented milk increases bone mineral density and bone mineral content in relation to body weight in the long-term feeding of growing rats. The mechanism of L. helveticus remains to be discovered.  相似文献   
47.
Ethylene oxide (EtO) is widely used by the health industry for sterilizing heat-sensitive devices. About 100 000 workers are regularly exposed to this chemical, used in an estimated 10 000 sterilizing units in U.S. health care facilities. Based on recent findings. NIOSh has recommended that EtO be regarded as a potential carcinogen and has urged OSHA to reexamine its present standard of 50 ppm. The ACGIH Notice of Intended Changes for 1982 has proposed reducing the recommended limit from 10 ppm TWA to 1 ppm and considers EtO a suspect carcinogen for man. Because of this increasing concern for its toxicity, it is imperative that the exposures to EtO be assessed, and that all reasonable steps to reduce these exposures be taken. This study demonstrates the effects of local exhaust ventilation, sterilizer chamber temperature, and sterilizer relative humidity in relation to their influence on EtO plume directionality, concentration and duration. Using two Foxboro/Wilks Miran 1A General Purpose Gas Analyzers, EtO concentrations were simultaneously monitored both immediately above and below the sterilizer door during various process runs, at three different types of sterilizers. Sterilizer operating conditions were representative of temperatures (38-54 degrees C (100-130 degrees F)), and relative humidities (30-50%) commonly employed in the sterilization process. The effects of varying local exhaust parameters were observed. Results clearly demonstrated that EtO tends to flow upward when the sterilizer door is opened. In all cases, the highest concentrations were observed at the upper location. Local exhaust ventilation significantly reduced the concentration of EtO observed and lessened the duration for which these levels persisted. Changes in temperature and relative humidity, within the range cited, have not shown any significant differences in EtO evolution patterns, concentrations or duration.  相似文献   
48.
The selenium concentration of maternal and umbilical cord whole blood was determined by atomic absorption spectrophotometry in 21 parturients at term. Six placental and amniotic membrane tissue specimens were also investigated. The mean selenium concentrations in the maternal (0.73 +/- 0.15 mumol/l) and umbilical cord blood (0.77 +/- 0.18 mumol/l) were similar and without significant correlation. Placental (2.24 +/- 0.20 mumol/kg wet weight) and amniotic membrane tissue specimens (2.32 +/- 0.54 mumol/kg wet weight) also contained similar concentrations of selenium which were about 3 times higher than those in the maternal and umbilical cord blood. Low whole blood selenium concentration in Finnish parturients may be a sign of deficient nutritional intake of selenium during pregnancy. The relatively high concentration of selenium in the placenta and amniotic membranes on the other hand suggest that metabolically active organs are being provided primarily with this essential trace element.  相似文献   
49.
The epidemiological role of small rodents and certain human patterns of living for contraction of nephropathia epidemica (NE) was studied by interviewing 46 NE patients and 52 control subjects. The occurrence of small rodents in dwellings and cupboards was significantly commoner among NE patients than among control subjects. The results suggest a connection between NE and small rodents.  相似文献   
50.
Serum selenium was evaluated in relation to hepatic structure and function in 46 alcoholics with diagnostic liver biopsy classified into 4 groups by hepatic histology. Their serum selenium concentration varied from 12 to 88 micrograms/l and was lower (p less than 0.001) in all groups of alcoholics, ie patients with normal liver (53.0 +/- 20.7 micrograms/l, mean +/- SD), fatty liver (55.8 +/- 21.2 micrograms/l), alcoholic hepatitis (46.0 +/- 14.1 micrograms/l), and cirrhosis (41.1 +/- 12.8 micrograms/l), than in 25 healthy controls (88.7 +/- 11.0 micrograms/l). Serum selenium level was related to the severity of liver disease, and most reduced in subjects with decompensated alcoholic cirrhosis. Their serum selenium level (29.2 +/- 13.7 micrograms/l) was below (p less than 0.05) that obtained in alcoholics with normal liver and fatty liver respectively. Both inadequate dietary selenium intake and alcohol-induced changes in hepatic structure and function may have contributed to the decrease of serum selenium in the subjects studied.  相似文献   
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