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141.
142.
Jankelowitz L  Reid KJ  Wolfe L  Cullina J  Zee PC  Jain M 《Chest》2005,127(5):1593-1599
STUDY OBJECTIVES: Cystic fibrosis (CF) patients may be predisposed to poor sleep quality due to upper and lower airway abnormalities and impaired gas exchange. Previous sleep investigations of CF patients using single-night polysomnography have reported conflicting results. We hypothesized that sampling sleep for a prolonged period in a patient's normal environment may give a more representative assessment of sleep quality than a single-night polysomnogram, and that impaired sleep quality would correlate with pulmonary disease severity and self-assessed sleep quality. DESIGN: Using wrist actigraphy, we measured sleep quality in clinically stable CF patients and age-matched control subjects. In addition, each CF patient and control subject completed the following three questionnaires: the Epworth sleepiness scale; the Pittsburgh sleep quality index (PSQI); and the Medical Outcomes Study 36-item short form. RESULTS: Twenty CF patients and control subjects were enrolled in the study, and were well-matched for age, sex, and body mass index. The mean (+/- SD) FEV(1) for CF patients was 61.0 +/- 20.1% predicted. CF patients and control subjects had similar sleep duration, sleep latency, and sleep efficiency. However, CF patients had higher PSQI scores (6.45 vs 4.55, respectively; p = .04), a higher fragmentation index (FI) [31.72 vs 18.02, respectively; p < 0.001], and less immobile time (88.87 vs 91.89, respectively; p = 0.02). There was a significant correlation of FI with FEV(1) and PSQI scores. CONCLUSIONS: Stable CF patients have disrupted sleep, and sleep disruption may in part be related to the severity of pulmonary disease. In addition, the PSQI may be useful in detecting CF patients with poor sleep quality.  相似文献   
143.
OBJECTIVE: The HLA-DRB1 "shared epitope" (SE) genotypes are associated with rheumatoid arthritis (RA), but it remains controversial whether the association is with incidence, severity, or both, whether there are associations in seronegative patients, and whether different DRB1 alleles that contain the SE have similar effects on RA susceptibility and/or severity. The present study was undertaken to study these issues in a large cohort of patients with RA. METHODS: White patients with RA of <6 months' duration (n = 793) were enrolled in an inception cohort. HLA-DRB1 typing was performed, and patients were categorized into 21 DRB1 genotype groups. The disability index of the Health Assessment Questionnaire was the primary outcome measure. RESULTS: DRB1 associations in seronegative RA patients closely resembled those in controls. Of seropositive patients, 21% had 2 copies of the epitope, 52% had 1 copy, and 27% had none. However, not all genotypes with 1 copy were associated with increased susceptibility; for example, frequencies of DRB1*0404/X and *01/X did not differ from those in controls. Absolute differences between seropositive RA patients and controls were greatest for DRB1*0401 homozygosity (3.8% versus 0.8%, respectively) and *0401/0404 heterozygosity (4.7% versus 1.0%). DRB1*0404 was increased in frequency in seropositive RA but, unlike *0401, an increased frequency was seen only with 2 epitope copies. The relatively rare DRB1*10 had an unexpected association with seropositive RA, being present in 1.7% of seropositive RA patients and 0.7% of controls, and also showed a trend toward association with greater disease severity. The presence of 2 epitope copies was associated with increased frequency of seropositivity and younger age at disease onset, not with disease severity. Treatment indication bias was substantial and may have accounted for some of these effects. HLA-DRB1*0401/0404 was found much more frequently in men and in patients with a lower age at disease onset, and there was a trend toward a higher frequency of *0404/0401 in women. CONCLUSION: This large inception cohort study confirms previously identified major associations and provides additional insights. Only one dominant association was found: *0401, which differs from other SE alleles in a single Lys-for-Arg substitution. The association of the rare DRB1*10 allele has not previously been postulated. Sex associations were confirmed. Associations with seronegative RA were not seen. Not all genotypes containing an SE copy showed increased susceptibility to RA. The association of SE genotypes found in this study related to disease susceptibility rather than severity.  相似文献   
144.
OBJECTIVE: To determine the risk of stroke in patients with rheumatoid arthritis (RA) and risk factors associated with stroke. METHODS: We performed nested case-control analyses within a longitudinal databank, matching up to 20 controls for age, sex, and time of cohort entry to each patient with stroke. Conditional logistic regression was performed as an estimate of the relative risk of stroke in RA patients compared with those with noninflammatory rheumatic disorders, and to examine severity and anti-tumor necrosis factor (anti-TNF) treatment effects in RA. RESULTS: We identified 269 patients with first-ever all-category strokes and 67 with ischemic stroke, including 41 in RA patients. The odds ratio (OR) for the risk of all-category stroke in RA was 1.64 (95% confidence interval [95% CI] 1.16-2.30, P = 0.005), and for ischemic stroke was 2.66 (95% CI 1.24-5.70, P = 0.012). Ischemic stroke was predicted by hypertension, myocardial infarction, low-dose aspirin, comorbidity score, Health Assessment Questionnaire score, and presence of total joint replacement, but not by diabetes, smoking, exercise, or body mass index. Adjusted for cardiovascular and RA risk factors, ischemic stroke was associated with rofecoxib (P = 0.060, OR 2.27 [95% CI 0.97-5.28]), and possibly with corticosteroid use. Anti-TNF therapy was not associated with ischemic stroke (P = 0.584, OR 0.80 [95% CI 0.34-1.82]). CONCLUSION: RA is associated with increased risk of stroke, particularly ischemic stroke. Stroke is predicted by RA severity, certain cardiovascular risk factors, and comorbidity. Except for rofecoxib, RA treatment does not appear to be associated with stroke, although the effect of corticosteroids remains uncertain.  相似文献   
145.
146.
Standardized mortality ratios (SMRs) reported by Medicare compare mortality at individual dialysis facilities with the national average, and are currently adjusted for race. However, whether the adjustment for race obscures or clarifies disparities in quality of care for minority groups is unknown. Cox model-based SMRs were computed with and without adjustment for patient race for 5920 facilities in the United States during 2010. The study population included virtually all patients treated with dialysis during this period. Without race adjustment, facilities with higher proportions of black patients had better survival outcomes; facilities with the highest percentage of black patients (top 10%) had overall mortality rates approximately 7% lower than expected. After adjusting for within-facility racial differences, facilities with higher proportions of black patients had poorer survival outcomes among black and non-black patients; facilities with the highest percentage of black patients (top 10%) had mortality rates approximately 6% worse than expected. In conclusion, accounting for within-facility racial differences in the computation of SMR helps to clarify disparities in quality of health care among patients with ESRD. The adjustment that accommodates within-facility comparisons is key, because it could also clarify relationships between patient characteristics and health care provider outcomes in other settings.  相似文献   
147.

Purpose

This study described physical and psychosocial limitations associated with adult brachial plexus injuries (BPI) and patients’ expectations of BPI surgery.

Methods

During in-person interviews, preoperative patients were asked about expectations of surgery and preoperative and postoperative patients were asked about limitations due to BPI. Postoperative patients also rated improvement in condition after surgery. Data were analyzed with qualitative and quantitative techniques.

Results

Ten preoperative and 13 postoperative patients were interviewed; mean age was 37 years, 19 were men, all were employed/students, and most injuries were due to trauma. Preoperative patients cited several main expectations, including pain-related issues, and improvement in arm movement, self-care, family interactions, and global life function. Work-related expectations were tailored to employment type. Preoperative and postoperative patients reported that pain, altered sensation, difficulty managing self-care, becoming physically and financially dependent, and disability in work/school were major issues. All patients reported making major compensations, particularly using the uninjured arm. Most reported multiple mental health effects, were distressed with long recovery times, were self-conscious about appearance, and avoided public situations. Additional stresses were finding and paying for BPI surgery. Some reported BPI impacted overall physical health, life priorities, and decision-making processes. Four postoperative patients reported hardly any improvement, four reported some/a good deal, and five reported a great deal of improvement.

Conclusions

BPI is a life-altering event affecting physical function, mental well-being, financial situation, relationships, self-image, and plans for the future. This study contributes to clinical practice by highlighting topics to address to provide comprehensive BPI patient-centered care.  相似文献   
148.
Hypotriglyceridemic effects of levonorgestrel in rats   总被引:2,自引:0,他引:2  
The progestin, levonorgestrel administered orally to fed female rats significantly lowers both plasma total and very low density lipoprotein triglycerides. In contrast, plasma total cholesterol and low density lipoprotein cholesterol rose significantly. Suspensions of isolated hepatocytes were used to study the effects of levonorgestrel on triglyceride synthesis by examining the incorporation of labelled precursors [( 9,10- 3H]palmitate and [U-14C]glycerol) into triglycerides. Levonorgestrel (10(-4) M) significantly inhibited the incorporation of both precursors into hepatocyte triglycerides and also reduced their incorporation into the triglycerides (nearly all in d less than 1.006) released into the medium. These results suggest that inhibition of hepatic triglyceride synthesis and release can account at least for part of the lowering of plasma VLDL which occurs during administration of levonorgestrel.  相似文献   
149.

Background

Cyclooxygenase-2 (COX-2, PTGS2) is an enzyme involved in the synthesis of prostaglandins and thromboxanes, which are regulators of biologic processes such as inflammation, cell proliferation and angiogenesis. COX-2 over-expression was reported in many (pre) malignant tissues, but data strongly vary and seem to depend on the methodology used.

Methods

Normal colorectal mucosa and paired cancerous tissue from 60 patients with colorectal cancer was investigated for the levels of COX-2 mRNA by real-time quantitative Polymerase Chain Reaction (qPCR). COX-2 levels were expressed relative to either: tissue weight or levels of the housekeeping genes beta-2 microglobulin (B2M) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH).

Results

COX-2 mRNA levels, normalized with respect to tissue weight or mRNA levels of the housekeeping genes B2M or GAPDH, were over-expressed in 80%, 70% and 40% of the colorectal tumor tissues, as compared to the paired adjacent normal colorectal mucosa samples, respectively. Highest mRNA COX-2 ratios tumor/normal were measured when expressed per mg tissue (mean ratio 21.6). When normalized with respect to the housekeeping genes B2M or GAPDH, mean tumor/normal ratios were 16.1 and 7.5, respectively.

Conclusion

Expression of COX-2 mRNA levels per mg tissue is most simple in comparison to normalization with respect to the housekeeping genes B2M or GAPDH. Levels of COX-2 mRNA are found over-expressed in almost 80% of the colorectal tumors, compared to paired adjacent normal colorectal mucosa, suggesting a role of COX-2 as a potential biomarker for cancer risk, whereas inhibitors of COX-2 could be of value in chemoprevention of colon cancer.  相似文献   
150.
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