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991.

Objective

To evaluate the aldose reductase inhibitory (ARI) activity of different fractions of Hybanthus enneaspermus for potential use in diabetic cataract.

Methods

Total phenol and flavonoid content of different fractions was determined. ARI activity of different fractions in rat lens was investigated in vitro.

Results

The results showed significant level of phenolic and flavonoid content in ethyl acetate fraction [total phenol (212.15±0.79 mg/g), total flavonoid (39.11±2.27 mg/g)] and aqueous fraction [total phenol (140.62±0.57 mg/g), total flavonoid (26.07±1.49 mg/g)] as compared with the chloroform fraction [total phenol (68.56±0.51 mg/g), total flavonoid (13.41±0.82 mg/g)] and petrolium ether fraction [total phenol (36.68±0.43 mg/g), total flavonoid (11.55±1.06 mg/g)]. There was a significant difference in the ARI activity of each fraction, and it was found to be the highest in ethyl acetate fraction [IC50 (49.26±1.76 µg/mL)] followed by aqueous extract [IC50 (70.83±2.82 µg/mL)] and it was least in the petroleum ether fraction [IC50 (118.89±0.71 µg/mL)]. Chloroform fraction showed moderate activity [IC50 (98.52±1.80 µg/mL)].

Conclusions

Different fractions showed significanct amount of ARI activity, where in ethyl acetate fraction it was found to be maximum which may be due to its high phenolic and flavonoid content. The extract after further evaluation may be used in the treatment of diabetic cataract.  相似文献   
992.

Background

Leucoreduction of blood products is increasingly being employed to produce blood products with residual WBCs < 5 × 106 per unit (99.9 percent or a log 3 leucoreduction). Clinical data suggests that non-haemolytic febrile transfusion reactions can be prevented by leucodepletion. The procedure also prevents alloimmunisation to HLA antigens in patients who will repeatedly require transfusion of blood/blood products.

Method

Of the methods available to reduce the number of WBC in blood products washing of red cells, freezing and deglycerolisation are effective and yield a product with only a 24 hour shelf life. Other methods such as leucodepletion filters are relatively inexpensive, simple and the final product has a normal shelf life. Modern generation of leucoreduction filters and apheresis machines can provide greater than 4 log reduction of WBC.

Results

After the introduction of leucodepletion of blood for Thalassemics at our center in 2003, the incidence of non haemolytic febrile transfusion reactions (NHFTR) fell from 4% in 2002 to 1% in 2003.

Conclusion

In patients undergoing long-term blood transfusion therapy e.g. Thalassemics, alloimmunisation against the HLA antigens on donor white cells is prevented by leucodepletion and prevents NHFTRs.Key Words: Leucoreduction, leucodepletion, alloimmunisation  相似文献   
993.
994.
Low phylloquinone (vitamin K1) intakes have been associated with low bone mineral density in older adults. Phylloquinone intakes and serum undercarboxylated osteocalcin (ucOC) levels were assessed in ninety-seven apparently healthy, free-living Irish women aged 50-75 years. Phylloquinone intakes were estimated using a detailed dietary history, which measured habitual food intakes from a typical 14 d period, and recently published food composition data for phylloquinone. Fasting serum ucOC was measured using an enzyme immunoassay. The median daily intake of phylloquinone in the group from all sources was 108.8 microg and from food sources only was 106.6 microg, indicating that approximately 99 % of the phylloquinone came from food. Vegetables and vegetable dishes contributed 67 % of the total phylloquinone intake, but further analysis showed that broccoli, cabbage and lettuce were the primary sources, making a total contribution of 44 %. Twenty per cent of the women had a phylloquinone intake below the UK recommendation of 1 microg/kg body weight per day and 34 % failed to meet the US Adequate Intake value of 90 microg/day. Mean serum ucOC levels in the women were 6.2 (SD 1.7) ng/ml and were predicted by phylloquinone intake (beta -2.20, generated from log-transformed phylloquinone intake data; P=0.04). On the basis of comparisons with both UK recommendations and US Adequate Intakes for phylloquinone, the habitual intakes of phylloquinone in a high proportion of Irish postmenopausal women may not be adequate.  相似文献   
995.
BACKGROUND: While winter-time vitamin D deficiency has been well-documented in Crohn's disease patients, less is known about vitamin D status during summertime and whether a seasonal variation exists in bone turnover. AIMS: To compare vitamin D status and bone turnover markers in Crohn's disease patients with age- and sex-matched controls during late-summer and late-winter. SUBJECTS: Crohn's disease patients (n = 44; mean age 36.9 years, currently in remission) and matched controls (n = 44) were recruited from Cork University Hospital and Cork City area, respectively. METHODS: Bloods were analysed for 25-hydroxyvitamin D, parathyroid hormone, bone-specific alkaline phosphatase, osteocalcin and urine analysed for N-telopeptides of type 1 collagen. RESULTS: Serum 25-hydroxyvitamin D concentrations were significantly (P < 0.003) lower in Crohn's disease patients than in control subjects during both seasons. In Crohn's disease patients, serum 25-hydroxyvitamin D concentrations were lower (P < 0.0001) whereas serum parathyroid hormone, osteocalcin and bone-specific alkaline phosphatase and urinary N-telopeptides of type 1 collagen levels were higher (P < 0.001) during late-winter than late-summer. CONCLUSION: There were notable seasonal variations in vitamin D status and bone turnover markers in Crohn's disease patients. The impact of winter decline in vitamin D status and increase in bone turnover on long-term risk of osteopenia/osteoporosis in Crohn's disease patients is unclear.  相似文献   
996.

Purpose

Despite an acknowledged dearth of data on serum 25-hydroxyvitamin D (25(OH)D) concentrations from Southern European countries, inter-country comparison is hampered by inconsistent data reporting. The purpose of the current study was to conduct a systematic literature review of available data on serum 25(OH)D concentrations and estimate vitamin D status in Southern European and Eastern Mediterranean countries, both at a population level and within key population subgroups, stratified by age, sex, season and country.

Methods

A systematic review of the literature was conducted to identify and retrieve scientific articles reporting data on serum 25(OH)D concentration and/or vitamin D status following standard procedures.

Results

Data were extracted from 107 studies, stratified by sex and age group, representing 630,093 individuals. More than one-third of the studies reported mean 25(OH)D concentrations below 50 nmol/L and ~?10% reported mean serum 25(OH)D concentrations below 25 nmol/L. Overall, females, neonates/ infants and adolescents had the higher prevalence of poor vitamin D status. As expected, there was considerable variability between studies. Specifically, mean 25(OH)D ranged from 6.0 (in Italian centenarians) to 158 nmol/L (in elderly Turkish men); the prevalence of serum 25(OH)D?<?50 nmol/L ranged from 6.8 to 97.9% (in Italian neonates).

Conclusions

Contrary to expectations, there was a high prevalence of low vitamin D status in the Southern Europe and the Eastern Mediterranean regions, despite abundant sunshine. These data further emphasize the need for strategies, such as fortification of foods with vitamin D and/or vitamin D supplementation, which will be tailored to the needs of specific population groups with higher risk of insufficiency or deficiency, to efficiently tackle the pandemic of hypovitaminosis D in Europe.
  相似文献   
997.
ObjectiveDietary intervention studies suggest that a daily fish meal can improve blood pressure (BP); however, such a dietary regimen might be difficult to sustain. The objective of the present study was to investigate whether salmon consumption three times per week improves BP during energy restriction in young adults.MethodsIn this 8-wk intervention, 324 subjects (20–40 y of age, body mass index 27.5–32.5 kg/m2, from Iceland, Spain, and Ireland) were randomized to one of four energy-restricted diets (?30% relative to estimated requirements): salmon (150 g three times per week, resulting in a daily consumption of 2.1 g of ω-3 long-chain polyunsaturated fatty acids [ω-3 LC-PUFAs]), cod (150 g three times per week, 0.3 g of ω-3 LC-PUFAs per day), fish oil capsules (1.3 g of ω-3 LC-PUFAs per day), or control (sunflower oil capsules, no seafood). Body weight, diastolic BP (DBP), systolic BP (SBP), and docosahexaenoic acid (DHA) in erythrocyte membrane were measured at baseline and endpoint.ResultsParticipants showed weight loss (?5.2 ± 3.2 kg, P < 0.001) and decreases in SBP (?4.4 ± 8.6 mmHg, P < 0.001) and DBP (?4.1 ± 7.4 mmHg, P < 0.001) after the intervention. The salmon (B = ?2.71, P = 0.032) and fish oil (B = ?2.48, P = 0.044) groups had significantly lower endpoint DPB than the cod group, but not significantly different from control. Lower baseline DHA (percentage) in erythrocytes was associated with greater DBP reductions (B = 0.576, P = 0.017).ConclusionSalmon consumption three times per week can decrease DBP similar to fish oil and significantly more than lean fish during an 8-wk energy restriction in young overweight individuals. A lower DHA content in erythrocyte membrane at baseline, which might indentify infrequent fish eaters, is associated with a greater DBP reduction in the course of an 8-wk dietary intervention providing fatty seafood.  相似文献   
998.
Food fortification is a potentially effective public health strategy to increase vitamin D intakes and circulating 25-hydroxyvitamin D [25(OH)D] concentrations. We updated a previous systematic review to evaluate current evidence from randomized controlled intervention studies in community-dwelling adults of the effect of fortified foods on 25(OH)D concentrations. Ovid MEDLINE, PubMed, CINAHL, Embase, and Cochrane Central Register of Controlled Trials were searched for randomized controlled intervention studies with vitamin D-fortified foods in free-living adults and data on circulating 25(OH)D. Two reviewers independently screened 441 papers for eligibility and extracted the relevant data. A meta-analysis of the absolute mean change in circulating 25(OH)D concentrations was conducted using a random effects model. Sixteen studies from 15 publications were included, of which 14 showed a significant effect of fortified foods on 25(OH)D concentrations. Heterogeneity was high (P = <0.0001, I(2) = 89%) and was partly explained by dose, latitude (range, 3-60°), and baseline 25(OH)D (range, 24.0-83.6 nmol/L). When combined in a random effects analysis (n = 1513; 767 treated, 746 controls), a mean individual intake of ~11 μg/d (440 IU/d) from fortified foods (range, 3-25 μg/d) increased 25(OH)D by 19.4 nmol/L (95% CI: 13.9, 24.9), corresponding to a 1.2 nmol/L (95% CI: 0.72, 1.68) increase in 25(OH)D for each 1 μg ingested. Vitamin D food fortification increases circulating 25(OH)D concentrations in community-dwelling adults. Safe and effective food-based strategies could increase 25(OH)D across the population distribution and prevent vitamin D deficiency with potential benefit for public health.  相似文献   
999.
1000.
Bony proliferation (exostoses) and vascular calcification are common in elderly men and women, but it is unclear whether they have a common etiology. Lateral lumbar and hand radiographs were obtained (1967–1970) in 777 men and 1,241 women (mean age 59, range 47–80 years) from the Framingham Heart Study. Each group of hand exostoses, specifically apiostoses (tufting), enthesophytes, and osteophytes, was graded on a scale of 0–3 (absent to severe) and summed across phalanges of digits 2–5. Anterior lumbar osteophytes were assessed in intervertebral spaces T12−L5 and abdominal aortic calcification (AAC) at lumbar segments L1-L4. Information on age, sex, body mass index, smoking, alcohol consumption, physical activity, systolic blood pressure, total cholesterol level, diabetes, and estrogen replacement therapy in women was obtained at the time of radiography and adjusted for in multivariate analyses. We used multivariable logistic regression models to assess the relationship between AAC (dependent variable) and exostoses for each sex. Multivariable adjusted logistic regression revealed a significant association between increased anterior lumbar osteophytes and prevalent AAC in men [odds ratio (OR) = 1.20, 95% confidence interval (CI) 1.1–1.3 per unit increase in osteophytes] and in women (OR = 1.25, 95% CI 1.1–1.4). There also was an inverse association between enthesophytes and AAC in women only (OR = 0.82, 95% CI 0.73–0.92). Apiostoses were weakly associated with AAC in men only. Hand osteophytes were not associated with AAC. In conclusion, in this cross-sectional study, anterior lumbar osteophytes and AAC occurred in the same individuals after adjustment for age and other covariates. In general, hand exostoses were not associated with aortic calcification.  相似文献   
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