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101.
In light of our limited understanding of what motivates older adults to participate in clinical studies of Alzheimer's disease (AD), the current study examines incentives and barriers to participating in AD clinical research among older adults. 235 participants enrolled in the Boston University Alzheimer's Disease Center research registry (75 ± 8 years, range 58-99 years, 60% female), a longitudinal registry from which individuals are recruited into other clinical studies, completed a survey assessing registry participation satisfaction, religiousness, trust in healthcare institutions, and medical research attitudes. Most participants reported initially enrolling in the registry for societal benefit. Insufficient time was a commonly endorsed barrier to enrolling in other Center-approved studies, particularly among younger participants. Driving and a lack of transportation to the medical facility were also barriers, particularly for older participants. Transportation was the most popular incentive, followed by home-based visits (particularly for older participants and participants with less formal education) and compensation (particularly among respondents from racial/ethnic minority groups). Participation interest in other studies was associated with favorable medical research attitudes (r = 0.34, p = 0.00003) but not religiousness (r = -0.09, p = 0.21), or trust in healthcare institutions (r = 0.09, p = 0.17). Among older adults, societal benefit is a motivating factor for registry enrollment; however, participation in additional studies is hindered by insufficient time among younger participants and transportation barriers among older participants. Providing transportation, home-based visits, and modest compensation may improve participation rates. Furthermore, favorable attitudes toward medical research are strongly associated with interest in enrolling in additional studies and may serve as a beneficial outreach triage technique.  相似文献   
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Background

Alcohol consumption has long been considered a trigger for recurrent gout attacks; however, this hypothesis has not been formally tested.

Methods

We conducted an Internet-based case-crossover study to assess several putative risk factors, including alcohol consumption, thought to trigger recurrent gout attacks. Subjects who had an attack within the past year were recruited online and asked to provide access to medical records pertaining to their gout. Data were obtained on the amount and type of alcoholic beverage consumed on each day over the 2-day period before a gout attack and on each day over a 2-day period during the intercritical period. We examined the amount and type of alcohol consumption and the risk of recurrent gout attacks using a conditional logistic regression adjusting for diuretic use and purine intake.

Results

A total of 197 subjects were recruited online over a 10-month period. Of those, 179 (91%) fulfilled the American College of Rheumatology Criteria for gout. Compared with no alcohol consumption, odds ratios for recurrent gout attacks were 1.1, 0.9, 2.0, and 2.5 for 1 to 2, 3 to 4, 5 to 6, and 7 or more drinks consumed over the 2-day period, respectively (P<.005). A dose-response relationship of risk of gout attacks was more evident for alcohol consumed over the last 24 hours. An increased risk of recurrent gout attacks was found for each type of beverage consumed.

Conclusion

Alcohol consumption triggers recurrent gout attacks. This effect was likely to occur within 24 hours after its consumption.  相似文献   
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African Americans (AA) with systemic sclerosis (SSc) have a worse prognosis compared to Americans of European descent (EA). We conducted the current study to test the hypothesis that AA patients with SSc have more severe disease and poorer outcomes compared to EA patients when afflicted with pulmonary arterial hypertension (PAH).We studied 160 consecutive SSc patients with PAH diagnosed by right heart catheterization, comparing demographics, hemodynamics, and outcomes between AA and EA patients.The cohort included 29 AA and 131 EA patients with similar baseline characteristics except for increased prevalence of diffuse SSc in AA. AA patients had worse functional class (FC) (80% FC III-IV vs 53%; p = 0.02), higher brain natriuretic peptide (NT-pro-BNP) (5729 ± 9730 pg/mL vs 1892 ± 2417 pg/mL; p = 0.02), more depressed right ventricular function, a trend toward lower 6-minute walk distance (263 ± 111  m vs 333 ± 110  m; p = 0.07), and worse hemodynamics (cardiac index 1.95 ± 0.58 L/min/m2 vs 2.62 ± 0.80 L/min/m2; pulmonary vascular resistance 10.3 ± 6.2 WU vs 7.6 ± 5.0 WU; p  < 0.05) compared with EA patients. Kaplan-Meier survival estimates for AA and EA patients, respectively, were 62% vs 73% at 2 years and 26% vs 44% at 5 years (p  > 0.05).In conclusion, AA patients with SSc-PAH are more likely to have diffuse SSc and to present with significantly more severe PAH compared with EA patients. AA patients also appear to have poorer survival, though larger studies are needed to investigate this association definitively.  相似文献   
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Data were analyzed from a multicenter observational cohort study of 1002 persons with AIDS or AIDS-related complex (ARC) and total CD4 cell count < 0.25 x 10(9)/L treated with zidovudine between April 1987 and April 1988. Cytomegalovirus (CMV) disease developed in 109 patients (10.9%), with a 2-year actuarial risk of 15%. Manifestations included retinitis (93 patients), esophagitis (10), colitis (8), gastritis (1), hepatitis (1), and encephalitis (1). The probability of CMV disease at 2 years for patients with initial counts < 0.1 x 10(9)/L was 21.4%, compared with 10.3% for patients with initial counts > or = 0.1 x 10(9)/L (P < .001). By proportional hazards analysis, baseline CD4 cell count < 0.1 x 10(9)/L, enrollment diagnosis of AIDS, and homosexuality were significantly associated with subsequently developing CMV disease. Median survival after diagnosis of CMV disease was 173 days, and CMV was an independent predictor of death. CMV contributes to AIDS-related morbidity and mortality. As new anti-CMV drugs become available, prophylaxis should be targeted at individuals with CD4 cell counts < 0.1 x 10(9)/L.  相似文献   
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Hospital acquired infections caused by enterococci are increasing in incidence. This increase has been attributed, in part, to widespread use of cephalosporin antibiotics which lack activity against enterococci. To test this hypothesis, we compared patients having nosocomial enterococcal pulmonary and wound infections with those patients having nosocomial staphylococcal infections for antecedant cephalosporin use. In a six month period, we found 14 instances of nosocomial enterococcal wound and respiratory infections; 13 were superinfections (occurring during or up to one week after administration of antimicrobials). Seven had coexisting pathogens noted. In the same six month period, 30 instances of Staphylococcus aureus nosocomial respiratory tract and wound infections were found and only 13 were superinfections (p less than 0.002 compared with enterococcal superinfections). Nine had coexisting pathogens noted. The mean age, gender distribution and underlying illnesses in the Staphylococcus aureus and enterococcal superinfection groups were comparable. Of the 14 instances of enterococcal nosocomial infections, 11 were associated with administration of a cephalosporin compared with seven of 30 for staphylococcal infections (p less than 0.002). Nosocomial enterococcal infections are commonly associated with antimicrobial therapy and the use of cephalosporins may selectively predispose patients to increased risk of enterococcal superinfections.  相似文献   
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