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51.
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Falling has been identified as a major complication in persons who have had a stroke. The purpose of this study was to investigate the effect of accumulated impairments on the risk of falling in community-dwelling stroke survivors. METHODS: Community-dwelling stroke survivors were identified from the Kansas City Stroke Study, a large cohort study of stroke survivors. We evaluated the subjects within 14 days of stroke onset. Impairments were determined at baseline and were defined as motor = Fugl-Meyer lower-limb score > 28, sensory = sensory score on National Institutes of Health (NIH) Stroke Scale > 0, and visual = hemianopsia score on NIH Stroke Scale > 0. Accumulated impairments were characterized as motor only (n = 101), motor + sensory (n = 88), and motor + sensory + visual (n = 47). The reference group did not possess motor, sensory, or visual impairments. We completed follow-ups at 1 month, 3 months, and 6 months poststroke to determine the fall status of the subjects. RESULTS: Two hundred eighty subjects were included. Falls were reported by 142 subjects (51%) between 1 month and 6 months poststroke. Univariate analysis revealed that the risk of falling for subjects with motor impairment only was odds ratio (OR) = 2.2 (95% confidence interval [CI] 1.05 to 4.70), motor + sensory impairments OR = 3.1 (95% CI 1.46 to 6.79), and motor + sensory + visual impairments OR = 2.4 (95% CI 1.05 to 5.83) as compared to the group with no motor, sensory, and visual impairments. In multiple logistic regression, the risk of falling increased with motor impairment only and motor + sensory impairments. However, the motor + sensory + visual impairments group had a lower risk of falling. Secondary analysis revealed a significant difference in mobility scores (Orpington Prognostic Scale-balance) among individuals with motor impairment only, motor + sensory impairments, motor + sensory + visual impairments, and the reference group. This lower risk of falling in stroke survivors with motor + sensory + visual impairments may be explained by more involved strokes, more impaired balance, and subsequently less mobility, therefore, lowering their risk of falling. In conclusion, community-dwelling persons who have had a stroke are at a higher risk of falling. However, the risk of falling is not linearly related to the number of impairments. Individuals with motor, sensory, and visual impairments are less mobile and less likely to fall than those individuals with motor deficits only or motor and sensory deficits.  相似文献   
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Previous studies have shown that cotinine, a metabolite of nicotine, may antagonize some of the therapeutic effects of nicotine. The mechanisms underlying cotinine's effects are unclear, but cotinine has been observed to increase serotonin levels in the brain. Thus, it is possible that blocking serotonin effects may antagonize the actions of cotinine, thereby reducing its impact on responses to nicotine. This study determined whether granisetron, a 5HT(3) receptor antagonist, would enhance the efficacy of the nicotine patch. Subjects were randomly assigned to one of the three granisetron conditions (N=43 for 2 mg/day; N=43 for 1 mg/day; N=42 for 0 mg/day) and asked to take the assigned medication daily during 15 days of tobacco abstinence. Because we were interested in interactions between cotinine and serotonin, all groups were also treated with a 21-mg nicotine patch. Assessments of withdrawal symptoms were made for 1 week during baseline smoking and several times during the experimental period. There was a near but nonsignificant difference among groups on a measure of tobacco withdrawal and no significant differences on global measures of drug effects or physiological measures. The data do not strongly support the hypothesis that 5HT(3) agonism is the mechanism by which cotinine offsets the effects of nicotine.  相似文献   
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SUMMARY: BACKGROUND Over-expression of the human epidermal growth factor receptor 2 (Her2) protooncogene is associated with poor prognosis among female patients with breast cancer. A polymorphism in the HER2 gene (I655V) has been associated with an elevated risk of breast cancer in some ethnic groups.METHODS Subjects from a community-based study of 5318 Ashkenazim from the Washington, DC area were selected for analysis of the I655V HER2 germline polymorphism. We estimated age-specific breast cancer risk from HER2 I655V based on the family history data, using the female first-degree relatives of the study participants and a novel extension of the kin cohort method.RESULTS The estimated cumulative risk of breast cancer to age 70 was approximately 30% higher among HER2 I655V carriers than noncarriers (RR = 1.33; 95% confidence interval [CI] = 1.03-1.83). The effect of the allele seems stronger at younger ages (among women younger than 50 years, RR = 2.11; CI = 1.39-3.28) and especially among younger women with a family history of breast cancer (RR = 8.9; CI = 1.9-19.7). Increased risk of breast cancer associated with the I655V allele was also observed among BRCA1/2 mutation carriers, although these results are based on small numbers.CONCLUSION These analyses suggest that the HER2 valine allele might be associated with increased risk of breast cancer, especially in young women and in women with a family history of the disease.  相似文献   
56.
BACKGROUND: Tobacco exposure reduction may be an alternative treatment approach for those tobacco users who are unwilling or unable to quit tobacco use. However, very little information is available on the feasibility of this type of intervention, especially in the area of oral moist snuff tobacco (ST). This pilot study examined whether reducing ST use using various methods can be achieved and whether this reduction results in lower exposure to carcinogens. METHODS: Moist snuff users (N=40 males) were randomly assigned to 4 mg nicotine gum, non-tobacco mint snuff, brand switching, or elimination of ST use in specific situations. These approaches were used to reduce ST use or nicotine exposure by at least 25% for the first 2 weeks and 50% the subsequent 6 weeks of treatment. Follow-up sessions occurred at 12 and 26 weeks. RESULTS: Significant reductions were observed in tins per week and cotinine levels across all conditions. Among the intent-to-treat population, the abstinence rate was 15% at 26 weeks. Reduction in nicotine exposure was associated with reduction in exposure to nitrosamines. CONCLUSION: Reduction in ST use may be a viable approach for those oral moist ST users with no immediate quit plans. Future research in this area is needed.  相似文献   
57.
A telephone survey of randomly-sampled churches, labor unions, supermarkets and restaurants was conducted in San Diego, California to determine the level of health promotion activities offered for members and customers. Nearly two-thirds of the churches offered health promotion programs, the bulk of which were single educational sessions. A similar proportion of labor unions reported programs, and most of them consisted of the distribution of materials and single-session group meetings. About one-third of the supermarkets reported activities, with most of these being the distribution of brochures. Similarly, about one-third of restaurants reported programs, which primarily consisted of the enforcement of nosmoking regulations. Very few organizations evaluated programs or desired assistance from health professionals. It was concluded that while secular health promotion programs are common and are available to many people, their quality and effectiveness are unknown. These findings present a challenge for public health professionals and agencies.A previous version of this paper was presented at the California Consensus Conference on Health Promotion in Santa Monica, May, 1987. John Elder is Associate Professor of Public Health at San Diego State University. James Sallis is Assistant Professor of Pediatrics at the University of California, San Diego. Nadia Hammond is Project Director for, and Susan Peplinski is a nutritionist with Project Salsa at San Diego State University. Joni Mayer is Assistant Professor of Public Health at San Diego State University.  相似文献   
58.
We have previously found that malnutrition is common among elderly diabetic patients in nursing homes. To determine the prevalence and nature of nutritional problems among ambulatory elderly diabetic patients, 60 Type II insulin-treated diabetic outpatients 65 years of age or older (mean ± SD 69.1±4.13 years) were evaluated consecutively. Anthropometric parameters and serum biochemical indices of protein calorie nutrition were assessed. The results were compared with those of 63 age-matched nondiabetic patients evaluated concurrently. The two groups, apart from the diagnosis of diabetes and its treatment, were comparable insofar as the number of medical problems and number of medications used. Diabetic patients were not significantly different from the controls in mean body weight and height, but mean body mass index (BMI) was slightly higher in diabetic patients. The lean body weight was not different compared to controls, but percent body fat was higher in diabetic patients. The adipose tissue was preferentially located in the upper body segment primarily in the subscapular and abdominal regions as evidenced by skinfold thickness measurements. There were no differences between the groups in midarm and midthigh muscle circumference. The serum triglyceride levels in the diabetic patients (335.8 ± 560.6 mg/dl) were significantly higher than those of controls (150.1 ± 57.7 mg/dl). There were no significant differences in total lymphocyte count or serum levels of cholesterol, albumin, prealbumin, transferrin and retinol binding protein. It is concluded that among ambulatory, elderly, diabetic patients, being underweight is rare.  相似文献   
59.

Background

Processed electroencephalogram (EEG) monitors help assess the hypnotic state during general anesthesia or sedation. Maintaining the bispectral index (BIS) or state entropy (SE) between 40 and 60 has been recommended to mitigate anesthesia awareness. Nonetheless, SEs > 70 were frequently observed at end-tidal sevoflurane concentrations unlikely to allow awareness. We sought to determine the prevalence of elevated discordant measurements during BIS and SE monitoring.

Methods

Electronic data collected over 11 months at two academic hospitals were retrospectively reviewed. At the hospital using SE, all cases were included with patients ≥ 18 yr and sevoflurane administered for at least 30 min during surgery. A cohort of cases propensity matched by age and American Society of Anesthesiologist Physical Status were selected from the hospital using BIS. Elevated discordant EEG indices were defined as values > 70 occurring during stable end-tidal sevoflurane concentrations > 1.5%. The odds ratio (OR) based on the probability of a case having at least one elevated discordant SE or BIS lasting ≥ two minutes (primary endpoint) was calculated.

Results

At each hospital, 3,690 cases were studied. The mean (95% confidence interval [CI]) incidence of cases with at least one interval of an elevated discordant EEG index lasting at least two minutes was 3.6% (2.8% to 4.4%) for SE compared with 0.24% (0.17% to 0.27%) for BIS (pooled OR, 17.0; 95% CI, 8.3 to 34.7; P < 0.001).

Conclusions

The prevalence of an elevated discordant EEG index is much greater with SE than with BIS. Elevated index values occurring at anesthetic concentrations well above the awareness threshold need to be assessed to determine if they indicate an inadequate depth of anesthesia requiring treatment or if they simply reflect the underlying monitoring algorithm.
  相似文献   
60.
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