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31.
A new phenolic amide, named cis-terrestriamide (7), together with ten known compounds (16, 811), were isolated from the methanolic extract of the fruits of Tribulus terrestris. The structure of 7 was elucidated on the basis of extensive analyses of 1D and 2D nuclear magnetic resonance spectroscopic and high resolution mass spectrometry data. Compounds 1, 2, 5, 6, 8, 9, and 11 exhibited inhibitory effects on the lipopolysaccharide-stimulated nitric oxide production in RAW 264.7 cells, with IC50 values of 18.7–49.4 μM.  相似文献   
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33.

Purpose

To evaluate the association between statin drug use and peripheral blood leukocyte telomere length in a U.S. nationally representative sample of adults.

Methods

We conducted a cross-sectional analysis of data from National Health and Nutrition Examination Survey 1999–2002, representative of the noninstitutionalized U.S. population. The analytic study population included 3496 men and women aged 40–84 years without a history of cancer and who had information of telomere length and statin use.

Results

Compared with nonusers, statin users were more likely to be former smokers, older, white, male, and had more comorbidities. Statin users did not have longer telomeres than nonusers after age (coefficient ?0.013, p = .30) and multivariable (0.0003, p = .98) adjustment. After multivariable adjustment, log-transformed telomere length nonstatistically significantly increased with increasing duration of use (0.003, p-trend = .11), which did not differ by number of comorbidities (p-interaction = 0.18). Compared with nonuse, more than 5 years of use had an odds ratio of telomere length above the 75th percentile of 1.62 (95% confidence interval 0.90–2.92; p-trend = .10).

Conclusions

Although telomere length appeared to be longer with longer duration of use of a statin, this association was not statistically significant, and we could not rule out bias as the explanation.  相似文献   
34.

Background Clinical pharmacy is key to the quality use of medicines. While there are different approaches in different countries, international perspectives may inform health service development. The Vietnamese Ministry of Health introduced a legal regulation of clinical pharmacy services in December 2012. Objective To describe the services, and to explore reported barriers and facilitators in implementing clinical pharmacy activities in Vietnamese hospitals after the introduction of Vietnamese Ministry of Health legal regulation. Setting Thirty-nine hospitals in Hanoi, Vietnam, including 22 provincial and 17 district hospitals. Method A mixed methods study was utilized. An online questionnaire was sent to the hospitals. In-depth interviews were conducted with pairs of nominated pharmacists at ten of these hospitals. The questionnaire focused on four areas: facilities, workforce, policies and clinical pharmacy activities. Main outcome measure Proportion of clinical pharmacy activities in hospitals. Themes in clinical pharmacy practice. Results 34/39 (87%) hospitals had established clinical pharmacy teams. Most activities were non-patient-specific (87%) while the preliminary patient-specific clinical pharmacy services were available in only 8/39 hospitals (21%). The most common non-patient-specific activities were providing medicines information (97%), reporting adverse drug reactions (97%), monitoring medication usage (97%). The patient specific activities varied widely between hospitals and were ad hoc. The main challenges reported were: lack of workforce and qualified clinical pharmacists. Conclusion While most hospitals had hospital-based pharmacy activities, the direct patient care was limited. Training, education and an expanded work forces are needed to improve clinical pharmacy services.

  相似文献   
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36.
Brønsted acidic ionic liquid was found to be an efficient and recyclable catalyst for the synthesis of benzo[4,5]imidazo[1,2-a]pyrimidines and 2,3-dihydroquinazolin-4(1H)-ones. The reactions proceeded smoothly with a broad scope of substrates providing the expected products in good to excellent yields under an atom-economical pathway. The low-cost recyclable catalyst, metal- and solvent-free conditions, and the ease of product isolation are the highlighted advantages in solving the issue of trace metal contamination in synthesized pharmaceuticals.

A facile, efficient, and atom-economic method for preparing benzo[4,5]imidazo[1,2-a]pyrimidines and 2,3-dihydroquinazolin-4(1H)-ones under metal- and solvent-free condition has been developed.  相似文献   
37.
Flavopiridol has been reported to induce apoptosis in lymphoid celllines via downregulation of bcl-2. The in vitro activity offlavopiridol against human chronic lymphocytic leukemia (CLL) cells andpotential mechanisms of action for inducing cytotoxicity were studied.The in vitro viability of mononuclear cells from CLL patients (n = 11) was reduced by 50% at 4 hours, 24 hours, and 4 days at aflavopiridol concentration of 1.15 µmol/L (95% confidence interval[CI] ±0.31), 0.18 µmol/L (95% CI±0.04), and 0.16 µmol/L (95% CI ±0.04), respectively. Loss ofviability in human CLL cells correlated with early induction ofapoptosis. Exposure of CLL cells to 0.18 µmol/L of flavopiridolresulted in both decreased expression of p53 protein and cleavage ofthe caspase-3 zymogen 32-kD protein with the appearance of its 20-kD subunit. Contrasting observations of others in tumor cell lines, flavopiridol cytotoxicity in CLL cells did not correlate with changesin bcl-2 protein expression alterations. We evaluated flavopiridol'sdependence on intact p53 by exposing splenocytes from wild-type(p53+/+) and p53 null (p53/) micethat demonstrated no preferential cytotoxicity as compared with amarked differential with F-ara-a and radiation. Incubation of CLL cellswith antiapoptotic cytokine interleukin-4 (IL-4) did not alter theLC50 of flavopiridol, as compared with a marked elevationnoted with F-ara-a in the majority of patients tested. These datademonstrate that flavopiridol has significant in vitro activity againsthuman CLL cells through activation of caspase-3, which appears to occurindependently of bcl-2 modulation, the presence of IL-4, or p53 status.Such findings strongly support the early introduction of flavopiridolinto clinical trials for patients with B-CLL.  相似文献   
38.
39.

Objectives

The aim of this study was to evaluate Streptococcus mutans adhesion to fluoride varnishes and subsequent change in biofilm accumulation and acidogenicity.

Methods

After producing fluoride varnish-coated hydroxyapatite discs using Fluor Protector (FP), Bifluorid 12 (BIF), Cavity Shield (CASH), or Flor-Opal Varnish White (FO), S. mutans biofilms were formed on the discs. To assess S. mutans adhesion to the discs, 4-h-old biofilms were analysed. To investigate the change in biofilm accumulation during subsequent biofilm formation, the biomass, colony forming units (CFU), and water-insoluble extracellular polysaccharides (EP) of 46-, 70-, and 94-h-old biofilms were analysed. To investigate the change in acidogenicity, pH values of the culture medium were determined during the experimental period. The amount of fluoride in the culture medium was also determined during the experimental period.

Results

BIF, CASH, and FO affected S. mutans adhesion (67–98% reduction) and subsequent biofilm accumulation in 46-, 70-, and 94-h-old biofilms. However, the reducing effect of the fluoride varnishes on the biomass, CFU count, water-insoluble EP amount, and acid production rate of the biofilms decreased as the biofilm age increased. These results may be related to the fluoride-release pattern of the fluoride varnishes. Of the fluoride varnishes tested, FO showed the highest reducing effect against the bacterial adhesion and subsequent biofilm accumulation.

Conclusions

Our findings suggest that if the results of these experiments are extrapolable to the in vivo situation, then reduced clinical benefit of using fluoride varnishes may occur with time.

Clinical significance

Fluoride varnish application can affect cariogenic biofilm formation but the anti-biofilm activity may be reduced with time.  相似文献   
40.
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