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471.
Cystatin C: a marker of renal function or something more?   总被引:4,自引:0,他引:4  
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473.
Acetaminophen decreases glutathione levels in the lung, which may predispose to oxidative injury and bronchospasm. Acetaminophen use has been associated with asthma in cross-sectional studies and a birth cohort. We hypothesized that acetaminophen use would be associated with newly diagnosed adult-onset asthma in the Nurses' Health Study, a prospective cohort study of 121,700 women. Participants were first asked about frequency of acetaminophen use in 1990. Cases with asthma were defined as those with a new physician diagnosis of asthma between 1990 and 1996 plus reiteration of the diagnosis and controller medication use. Proportional hazard models included age, race, socioeconomic status, body mass index, smoking, other analgesic use, and postmenopausal hormone use. During 352,719 person-years of follow-up, 346 participants reported a new physician diagnosis of asthma meeting diagnostic criteria. Increasing frequency of acetaminophen use was positively associated with newly diagnosed asthma (p for trend = 0.006). The multivariate rate ratio for asthma for participants who received acetaminophen for more than 14 days per month was 1.63 (95% confidence interval, 1.11-2.39) compared with nonusers. It would be premature to recommend acetaminophen avoidance for patients with asthma, but further research on pulmonary responses to acetaminophen is necessary to confirm or refute these findings and to identify subgroups whose asthma may be modified by acetaminophen.  相似文献   
474.
BACKGROUND: Essential fatty acids modulate inflammation and glucose metabolism and may alter infection risk. OBJECTIVE: We examined the association between intakes of n-6 and n-3 fatty acids and fish and the risk of community-acquired pneumonia. DESIGN: We prospectively evaluated 38,378 male US health professionals aged 44-79 y at the outset. We updated medical and lifestyle information biennially through questionnaires and diet every 4 y with the use of a validated food-frequency questionnaire. We excluded men who reported pneumonia, myocardial infarction, stroke, other heart disease, arterial surgery, cancer, or asthma before 1990 or those with incomplete dietary data. Community-acquired pneumonia was determined by blinded medical record review of chest radiographs. RESULTS: During 10 y of follow-up, there were 441 new cases of nonfatal community-acquired pneumonia. Pneumonia risk was lower in men in the highest energy-adjusted quintiles of intake than in men in the lowest quintiles of intake of linoleic acid [multivariate relative risk (RR): 0.70; 95% CI: 0.51, 0.96; P for trend = 0.01] and alpha-linolenic acid (multivariate RR: 0.68; 95% CI: 0.50, 0.93; P for trend = 0.01). Pneumonia risk decreased 4% for every 1-g/d increase in linoleic acid intake (multivariate RR: 0.96; 95% CI: 0.93, 0.99). Pneumonia risk was reduced by 31% for every 1-g/d increase in alpha-linolenic acid intake (multivariate RR: 0.69; 95% CI: 0.51, 0.93). Intakes of eicosapentaenoic acid and docosahexaenoic acid were not significantly related to pneumonia risk. CONCLUSION: Higher intakes of alpha-linolenic and linoleic acids and possibly of fish may reduce the risk of pneumonia.  相似文献   
475.
Approximately 10 million adults in the United States have experienced the passage of a kidney stone, and up to 5 million have been diagnosed with gout by a physician. Previous reports have suggested that gout increases the risk for the development of kidney stones, but there are no prospective data. We used data from a cohort of 51,529 male health care professionals to examine the independent association between gout and kidney stone disease. In a cross-sectional analysis of gout and kidney stone disease reported on the 1986 baseline questionnaire, the prevalence of kidney stone disease was almost twofold higher in men with history of gout compared to those without (15% vs. 8%). After adjusting for age and body mass index (BMI), a history of gout remained significantly associated with kidney stone disease (OR 1.88; 95% CI 1.68 to 2.11). We then prospectively examined the risk of incident kidney stones in men with and without a confirmed diagnosis of gout after excluding men who reported a history of kidney stone disease or gout on the baseline questionnaire. A confirmed diagnosis of gout increased the multivariate relative risk of incident kidney stones (RR 2.12; 95% CI 1.22 to 3.68). In contrast, a history of kidney stone disease was not associated with increased risk of gout (RR 1.05; 95% CI 0.54 to 2.07). In conclusion, a history of gout independently increases the risk for incident kidney stones in men. Physicians should provide dietary counseling, such as increasing fluid intake and decreasing salt consumption, to subjects with gout in addition to other risk factors, such as family history of kidney stones, in order to decrease the likelihood of stone formation.  相似文献   
476.
Emerging evidence suggests an inverse relation between vitamin D and blood pressure. We examined the independent association between intake of vitamin D and the risk of incident hypertension among participants of 3 large and independent prospective cohorts: Nurses Health Study I (NHS I; n=77,436), NHS II (n=93,803), and Health Professionals' Follow-up Study (HPFS; n=38,074). Relative risks and 95% confidence intervals for incident hypertension were computed according to quintiles of vitamin D intake using Cox proportional hazards regression and adjusted for relevant covariates. Each cohort was followed for > or =8 years. Vitamin D intake was not associated with the risk of developing hypertension. The multivariable relative risk estimates for the highest compared with lowest quintile of intake were 0.98 (0.93 to 1.04) in NHS I, 1.13 (0.99 to 1.29) in NHS II, and 1.03 (0.93 to 1.15) in HPFS. When we compared participants who consumed > or =1600 to <400 IU per day and those who consumed > or =1000 to <200 IU per day, no association was found. We conclude that higher intake of vitamin D is not associated with a lower risk of incident hypertension.  相似文献   
477.
OBJECTIVE: Various commonly consumed foods have long been suspected of affecting the serum uric acid level, but few data are available to support or refute this impression. Our objective was to evaluate the relationship between dietary factors and serum uric acid levels in a nationally representative sample of men and women in the US. METHODS: Using data from 14,809 participants (6,932 men and 7,877 women) ages 20 years and older in the Third National Health and Nutrition Examination Survey (for the years 1988-1994), we examined the relationship between the intake of purine-rich foods, protein, and dairy products and serum levels of uric acid. Diet was assessed with a food-frequency questionnaire. We used multivariate linear regression to adjust for age, sex, total energy intake, body mass index, use of diuretics, beta-blockers, allopurinol, and uricosuric agents, self-reported hypertension and gout, serum creatinine level, and intake of alcohol. RESULTS: The serum uric acid level increased with increasing total meat or seafood intake and decreased with increasing dairy intake. After adjusting for age, the differences in uric acid levels between the extreme quintiles of intake were 0.48 mg/dl for total meat (95% confidence interval [95% CI] 0.34, 0.61; P < 0.001 for trend), 0.16 mg/dl for seafood (95% CI 0.06, 0.27; P = 0.005 for trend), and -0.21 mg/dl for total dairy intake (95% CI -0.37, -0.04; P = 0.02 for trend). After adjusting for other covariates, the differences between the extreme quintiles were attenuated but remained significant (P < 0.05 for all comparisons). The total protein intake was not associated with the serum uric acid level in multivariate analyses (P = 0.74 for trend). Those who consumed milk 1 or more times per day had a lower serum uric acid level than did those who did not drink milk (multivariate difference -0.25 [95% CI -0.40, -0.09]; P < 0.001 for trend). Similarly, those who consumed yogurt at least once every other day had a lower serum uric acid level than did those who did not consume yogurt (multivariate difference -0.26 [95% CI -0.41, -0.12]; P < 0.001 for trend). CONCLUSION: These findings from a nationally representative sample of adults in the US suggest that higher levels of meat and seafood consumption are associated with higher serum levels of uric acid but that total protein intake is not. Dairy consumption was inversely associated with the serum uric acid level.  相似文献   
478.
479.
Context  Randomized trials of short-term aspirin use for prevention of recurrent colorectal adenoma have provided compelling evidence of a causal relationship between aspirin and colorectal neoplasia. However, data on long-term risk of colorectal cancer according to dose, timing, or duration of therapy with aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) remain limited. Objective  To examine the influence of aspirin and NSAIDs in prevention of colorectal cancer. Design, Setting, and Participants  Prospective cohort study of 82 911 women enrolled in the Nurses’ Health Study providing data on medication use biennially since 1980 and followed up through June 1, 2000. Main Outcome Measure  Incident colorectal cancer. Results  Over a 20-year period, we documented 962 cases of colorectal cancer. Among women who regularly used aspirin (2 standard [325-mg] tablets per week), the multivariate relative risk (RR) for colorectal cancer was 0.77 (95% confidence interval [CI], 0.67-0.88) compared with nonregular users. However, significant risk reduction was not observed until more than 10 years of use (P.001 for trend). The benefit appeared related to dose: compared with women who reported no use, the multivariate RRs for cancer were 1.10 (95% CI, 0.92-1.31) for women who used 0.5 to 1.5 standard aspirin tablets per week, 0.89 (95% CI, 0.73-1.10) for 2 to 5 aspirin per week, 0.78 (95% CI, 0.62-0.97) for 6 to 14 aspirin per week, and 0.68 (95% CI, 0.49-0.95) for more than 14 aspirin per week (P<.001 for trend). Notably, women who used more than 14 aspirin per week for longer than 10 years in the past had a multivariate RR for cancer of 0.47 (95% CI, 0.31-0.71). A similar dose-response relationship was found for nonaspirin NSAIDs (P = .007 for trend). The incidence of reported major gastrointestinal bleeding events per 1000 person-years also appeared to be dose-related: 0.77 among women who denied any aspirin use; 1.07 for 0.5 to 1.5 standard aspirin tablets per week; 1.07 for 2 to 5 aspirin per week; 1.40 for 6 to 14 aspirin per week; and 1.57 for more than 14 aspirin per week. Conclusions  Regular, long-term aspirin use reduces risk of colorectal cancer. Nonaspirin NSAIDs appear to have a similar effect. However, a significant benefit of aspirin is not apparent until more than a decade of use, with maximal risk reduction at doses greater than 14 tablets per week. These results suggest that optimal chemoprevention for colorectal cancer requires long-term use of aspirin doses substantially higher than those recommended for prevention of cardiovascular disease, but the dose-related risk of gastrointestinal bleeding must also be considered.   相似文献   
480.
Objectives. To estimate the proportion of U.S. men affected by specific lower urinary tract symptoms (LUTS) and to assess whether the prevalence of LUTS varies by race/ethnicity.Methods. Included were 30+-year-old men who took part in the Third National Health and Nutrition Examination Survey. Men were asked whether they experienced nocturia, incomplete emptying, or hesitancy. Men 60+ years old were also asked whether they had a decreased urinary stream or had ever undergone noncancer prostate surgery. To obtain the estimated prevalences for the U.S. population, we applied sampling fraction weights. We calculated age-adjusted odds ratios (ORs) of 3+ symptoms or surgery by race/ethnicity using logistic regression analysis.Results. Only nocturia was common in 30 to 59-year-old men. Among men who had not had prostate surgery, 59.9% of men 60 to 69 years old and 75.1% of men 70+ years old had at least one symptom. All four symptoms were reported by 3.0% of men 60 to 69 years and 5.6% of men 70+ years old. Of the men 60 to 69 years old and men 70+ years old, 8.0% and 22.4%, respectively, reported having undergone surgery. In men 60+ years old, the age-adjusted OR for either having 3+ symptoms or surgery was 0.8 for non-Hispanic black men compared with non-Hispanic white men. The odds of having 3+ symptoms (OR = 1.6), but not surgery (OR = 1.1), appeared greater for Mexican-American men than for non-Hispanic white men.Conclusions. Specific LUTS are common in older U.S. men. Older black men were not more likely to have LUTS than were older white men. The apparent modestly higher prevalence of LUTS in older Mexican-American men requires additional study.  相似文献   
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