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81.
Non-medically indicated (NMI) deliveries prior to 39 weeks increase the risk of neonatal mortality, excess morbidity, and health care costs. The study’s purpose was to identify maternal and hospital characteristics associated with NMI deliveries prior to 39 weeks. The study included 207,775 births to women without a previous cesarean and 38,316 births to women with a previous cesarean, using data from Florida’s 2006–2007 linked birth certificate and inpatient record file. Adjusted risk ratios (ARR) and 95 % confidence intervals (CI) for characteristics were calculated using generalized estimating equation for multinomial logistic regression. Among women without a previous cesarean, NMI deliveries occurred in 18,368 births (8.8 %). Non-medically indicated inductions were more likely in women who were non-Hispanic white (ARR: 1.41, 95 % CI 1.31–1.52), privately-insured (ARR: 1.42, 95 % CI 1.26–1.59), and delivered in hospitals with <500 births per year. Non-medically indicated primary cesareans were more likely in women who were older than 35 years (ARR: 2.96, 95 % CI 2.51–3.50), non-Hispanic white (ARR: 1.44, 95 % CI 1.30–1.59), and privately-insured (ARR: 1.43, 95 % CI 1.17–1.73). Non-medically indicated primary cesareans were also more likely to occur in hospitals with <30 % nurse-midwife births, <500 births per year, and in large metro areas. Among women with previous cesarean, NMI repeat cesareans occurred in 16,746 births (43.7 %). Only weak risk factors were identified for NMI repeat cesareans. The risk factors identified varied by NMI outcome. This information can be used to inform educational campaigns and identify hospitals that may benefit from quality improvement efforts.  相似文献   
82.
83.
This paper, the second in the series, will build on the first and explore the importance of liver and pancreatic manifestations of cystic fibrosis (CF) and the effect on morbidity and mortality of this multifaceted genetic condition. It will also further develop the critical role of the gastroenterologist as part of the multidisciplinary group of clinicians and allied health staff in the effective management of patients with CF.  相似文献   
84.

Objective

We aimed to explore the impacts of new vaccine introductions on immunization programmes and health systems in low- and middle-income countries.

Methods

We conducted case studies of seven vaccine introductions in six countries (Cameroon, PCV; Ethiopia, PCV; Guatemala, rotavirus; Kenya, PCV; Mali, Meningitis A; Mali, PCV; Rwanda, HPV). Interviews were conducted with 261 national, regional and district key informants and questionnaires were completed with staff from 196 health facilities. Routine data from districts and health facilities were gathered on vaccination and antenatal service use. Data collection and analysis were structured around the World Health Organisation health system building blocks.

Findings

The new vaccines were viewed positively and seemed to integrate well into existing health systems. The introductions were found to have had no impact on many elements within the building blocks framework. Despite many key informants and facility respondents perceiving that the new vaccine introductions had increased coverage of other vaccines, the routine data showed no change. Positive effects perceived included enhanced credibility of the immunisation programme and strengthened health workers’ skills through training. Negative effects reported included an increase in workload and stock outs of the new vaccine, which created a perception in the community that all vaccines were out of stock in a facility. Most effects were found within the vaccination programmes; very few were reported on the broader health systems. Effects were primarily reported to be temporary, around the time of introduction only.

Conclusion

Although the new vaccine introductions were viewed as intrinsically positive, on the whole there was no evidence that they had any major impact, positive or negative, on the broader health systems.  相似文献   
85.
Molecular biomarkers have come to constitute one of the cornerstones of oncological pathology. The method of classification not only directly affects the manner in which patients are diagnosed and treated, but also guides the development of drugs and of artificial intelligence tools. The aim of this article is to organise and update gastrointestinal molecular biomarkers in order to produce an easy-to-use guide for routine diagnostics. For this purpose, we have extracted and reorganised the molecular information on epithelial neoplasms included in the 2019 World Health Organization classification of tumours. Digestive system tumours, 5th edn.  相似文献   
86.
Fullerene derivatives are used in a wide range of applications including as electron acceptors in solution-processable organic photovoltaics. We report agglomeration of fullerene derivatives in optically opaque solutions of PC61BM and PC71BM, with concentrations ranging from 30 mg mL−1 up to 90 mg mL−1, in different solvents with relevance to organic photovoltaics, using a novel neutron scattering technique, Spin-Echo Small Angle Neutron Scattering (SESANS). From SESANS, agglomerates with correlation lengths larger than 1 μm are found in some PC61BM solutions, in contrast no agglomerates are seen in PC71BM solutions. These results clearly show that PC71BM is fundamentally more soluble than PC61BM in the solvents commonly used in photovoltaic inks and corroborating similar observations previously achieved using other experimental techniques. Computer models are presented to study the energetics of solution and agglomeration of both species, ascribing the difference to a kinetic effect probably related to the larger anisotropy of PC71BM. Also, this work showcases the power of SESANS to probe agglomerates of fullerene derivatives in completely opaque solutions for agglomerates of the order of one to several microns.

Fullerene derivatives are used in a wide range of applications including as electron acceptors in solution-processable organic photovoltaics.  相似文献   
87.
88.
This paper presents a study of Al2O3–ZrO2 (ZTA) nanocomposites with different contents of reduced graphene oxide (rGO). The influence of the rGO content on the physico-mechanical properties of the oxide composite was revealed. Graphene oxide was obtained using a modified Hummers method. Well-dispersed ZTA-GO nanopowders were produced using the colloidal processing method. Using spark plasma sintering technology (SPS), theoretically dense composites were obtained, which also reduced GO during SPS. The microstructure, phase composition, and physico-mechanical properties of the sintered composites were studied. The sintered ZTA composite with an in situ reduced graphene content of 0.28 wt.% after the characterization showed improved mechanical properties: bending strength was 876 ± 43 MPa, fracture toughness—6.8 ± 0.3 MPa·m1/2 and hardness—17.6 ± 0.3 GPa. Microstructure studies showed a uniform zirconia distribution in the ZTA ceramics. The study of the electrical conductivity of reduced graphene oxide-containing composites showed electrical conductivity above the percolation threshold with a small content of graphene oxide (0.28 wt.%). This electrical conductivity makes it possible to produce sintered ceramics by electrical discharge machining (EDM), which significantly reduces the cost of manufacturing complex-shaped products. Besides improved mechanical properties and EDM machinability, 0.28 wt.% rGO composites demonstrated high resistance to hydrothermal degradation.  相似文献   
89.
1. Doxorubicin dose-dependently increased the cardiac contractility of isolated frog heart within the dose-range of 1.0 to 10.0 x 10(-7) M and dose-dependently increased the cardiac output of frog heart in situ with a dose-range between 10(-7) and 10(-5) M. 2. The results of the in situ investigation, using cardiac output as the index of cardiac contractility, were in agreement with the in vitro results. The positive inotropic effects of doxorubicin climaxed around 10(-5) M beyond which there was a dose-dependent decreased in contractility. 3. Haloperidol (10(-6) M), a dopaminergic receptor blocker, and propranolol (10(-8) M), a beta-adrenergic blocker, did not block the positive inotropic effects of doxorubicin. 4. These results provide sufficient basis to suggest that doxorubicin is acting on the isolated amphibian heart through a mechanism which is not associated with beta-adrenergic and/or dopaminergic receptors.  相似文献   
90.
Lomefloxacin (NY-198 or SC-47111) is a difluoro-quinolone derivative having a C-methyl at the 3-position of the piperazine ring, thus minimizing its metabolic alteration in vivo. In our research, its antimicrobial activity was most similar to that of difloxacin, enoxacin, fleroxacin, and norfloxacin but usually less than that of ciprofloxacin and ofloxacin against most species. Lomefloxacin shared cross-resistance with other 4-quinolones but remained very active against ceftazidime-resistant organisms, including stably derepressed beta-lactamase producing Gram-negative bacilli. Lower pH increased the lomefloxacin MICs. MBCs were usually identical to the measured MIC, and the lomefloxacin MICs were not significantly increased by high inoculum concentrations. The were found to have a very low rate of spontaneous mutation to lomefloxacin resistance (10−8–10−9). In vitro tests by 5-μg and 10-μg lomefloxacin disks and dilution methods were correlated, and the 10-μg disk was recommended for clinical trials using a ≤4 μg/ml susceptible breakpoint. The quality assurance guidelines for dilution tests were determined by a multilaboratory study.  相似文献   
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