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71.
72.
Formal assessment of dental vocational training (DVT) has been an issue since 1993 when DVT became mandatory for graduates wishing to practice within the NHS. There have been a number of other drivers for change, including concerns about the capabilities of new graduates, a lack of standardisation of the training experience and accountability for standards of training. All of these factors contributed to the decision, by the Scottish Council for Postgraduate Medical and Dental Education (now part of NHS Education for Scotland--NES), to support a programme of research into the development of a competency-based system of assessment for DVT. During the life of this project the argument for introducing assessment of DVT and General Professional Training (GPT) has become ever stronger. 相似文献
73.
74.
Wareham NJ Jakes RW Rennie KL Mitchell J Hennings S Day NE 《International journal of epidemiology》2002,31(1):168-174
BACKGROUND: Physical activity is an important lifestyle which is often poorly assessed in epidemiological studies. The European Prospective Investigation into Cancer Study-Norfolk cohort (EPIC-Norfolk), a large population-based cohort study, has developed a comprehensive questionnaire to assess activity in different domains of life aimed at assessing total energy expenditure. We report the repeatability of this instrument and its validity against repeated objective measures of fitness and energy expenditure undertaken throughout the time frame of reference of the questionnaire. METHODS: The validity of the instrument was measured in 173 individuals randomly selected from a continuing population-based cohort study. Energy expenditure was assessed by four separate episodes of 4-day heart-rate monitoring, a method previously validated against whole body calorimetry and doubly-labelled water. Cardio-respiratory fitness was assessed by four repeated measures of sub-maximum oxygen uptake. At the end of the 12-month period, participants completed the physical activity questionnaire that assesses past-year activity at home, work and in recreation. Repeatability was assessed in a separate group of 399 randomly selected participants in EPIC who completed the physical activity questionnaire twice with a 3-month interval. RESULTS: The age- and sex-adjusted correlation between the objective measure of daytime energy expenditure and the sum of recreational and occupational reported physical activity (in MET h per week) was 0.28 (P < 0.001). The reported time spent in vigorous activity was correlated with cardio-respiratory fitness (0.16, P < 0.05) and with the proportion of time when energy expenditure was more than five times basal (0.17, P < 0.05). The repeatability of the sum of recreational and occupational reported activity was high, r = 0.73. CONCLUSIONS: The indices of physical activity derived from this questionnaire have levels of validity and repeatability comparable to other physical activity instruments that are used in large epidemiological studies and which have undergone such intense development and testing. 相似文献
75.
Context To determine whether journals have improved their disclosure of ethical protections in clinical trials. Methods Comparison of clinical trials published before and after 1997 (July 1995 to December 1996 and January 1998 to June 1999) in Annals of Internal Medicine, BMJ, JAMA, The Lancet, and The New England Journal of Medicine. Sixty articles per journal per period were randomly selected and assessed for rate of reporting on informed consent and on ethics committee approval. Results Informed consent was not described in 79 articles (26%) published before 1997 vs 53 (18%) published after 1997 (P = .01), and ethics committee approval was not mentioned in 93 (31%) before 1997 vs 54 (18%) after 1997 (P<.001). Neither protection was described in 48 articles (16%) published before 1997 vs 28 (9%) after 1997 (P = .01). In subgroup analyses, those journals with the worst initial rates generally improved the most. BMJ did not describe informed consent in 25 articles (42%) before 1997 vs 15 (25%) after 1997 (P = .05), and JAMA did not describe ethics committee approval in 25 (42%) before 1997 vs 13 (22%) after 1997 (P = .02). BMJ, JAMA, and Annals had the lowest initial rates of reporting on both protections in the same article, with 25 (42%), 32 (53%), and 34 (57%), respectively, but improved markedly to 38 (63%), 43 (72%), and 45 (75%) (P = .02, .04, and .03, respectively). Conclusions Major medical journals have improved their reporting on informed consent and ethics committee approval; however, 9% of studies still report neither. 相似文献
76.
Maspin expression profile in human prostate cancer (CaP) and in vitro induction of Maspin expression by androgen ablation. 总被引:6,自引:0,他引:6
77.
The neuroprotective agent sipatrigine (BW619C89) potently inhibits the human tandem pore-domain K(+) channels TREK-1 and TRAAK 总被引:2,自引:0,他引:2
Meadows HJ Chapman CG Duckworth DM Kelsell RE Murdock PR Nasir S Rennie G Randall AD 《Brain research》2001,892(1):182-101
We have cloned and functionally expressed the human orthologue of the mouse TRAAK gene. When cDNA for hTRAAK is expressed in either Xenopus oocytes or HEK293 cells it forms a K(+)-selective conductance and hyperpolarises the resting membrane potential. Quantitative mRNA expression analysis using Taqman revealed that hTRAAK mRNA is predominantly present in the central nervous system where it exhibits a regionally diverse pattern of expression. Like the related channel TREK-1, the activity of TRAAK was potentiated by arachidonic acid. The neuroprotective agent sipatrigine (10 microM) inhibited both hTREK-1 (73.3+/-4.4%) and hTRAAK (45.1+/-11.2%) in a reversible, voltage-independent manner. Inhibition of both channels was dose-dependent and for TREK-1 occurred with an IC(50) of 4 microM. The related compound lamotrigine, which is a better anticonvulsant but weaker neuroprotective agent than sipatrigine, was a far less effective antagonist of both channels, producing <10% inhibition at a concentration of 10 microM. 相似文献
78.
JW Gregory SA Greene RT Jung CM Scrimgeour MJ Rennie 《Archives of disease in childhood》1993,68(2):205-209
Fourteen children receiving one year of recombinant human growth hormone (rhGH) treatment underwent measurement of serial changes in body composition (measured by skinfold thickness, bioelectrical impedance, and H2(18)O dilution), resting energy expenditure (REE, estimated by ventilated hood indirect calorimetry), and total free living daily energy expenditure (TEE, measured by the doubly labelled water technique). Mean height velocity increased from 4.9 to 8.6 cm/year after six months of treatment. Fat free mass (FFM) increased more during the first six weeks (24.4 g/day) than from six to 26 weeks of treatment (6.8 g/day); fat mass decreased by 7.2 g/day and 1.1 g/day respectively. The six week increase in REE (kJ/day) was maintained after six months of treatment, though expressed per kilogram FFM (kJ/kgFFM/day), returned to pretreatment values by three months. Height velocity increases at six months correlated with six week changes in fat mass measured by skinfold thickness and REE, though use of this relationship to predict growth response in individuals is limited by the wide 95% prediction intervals. No significant changes in growth, body composition, or energy expenditure were observed between six and 12 months of treatment, in either patients who had initially responded well to treatment or those who were poor initial responders to treatment and who had their dose of rhGH doubled after six months. 相似文献
79.
A rat model of vaginal candidosis, suitable for screening new antifungal compounds or novel formulations was developed and validated. Two strains of Candida albicans, different inoculation schedules, quantitative assays for fungal burden and the necessity for immunosuppression were tested. The infection was evaluated clinically and histologically by fungal counts from the vaginal discharge. The animals without immunosuppression did not sustain the infection beyond 2-3 days, however, after immunosuppression with cyclophosphamide, the infection can be maintained for about 2 weeks and is suitable for the testing of topical antifungal therapies. 相似文献
80.
Congenital adenoma of the iris and ciliary body: light and electron microscopic observations. 下载免费PDF全文
A 23-year-old man had a lesion in the right inferior iris which appeared to have enlarged since it was first seen when the patient was aged 5 years. The lesion was excised by a partial iridocyclectomy. Histopathologically the neoplasm was composed of both pigmented and non-pigmented cells. Pseudoacini, containing acid mucopolysaccharides, were present throughout the tumour matrix. Electron microscopically the non-pigmented cells were found to possess a convoluted plasmalemma, abundant rough endoplasmic reticulum, and numerous desmosomes and gap junctions. The pigmented cells contained large, round, mature melanosomes, occasional premelanosomes, and desmosomes, which resembled the posterior pigment epithelium of the iris. The intercellular matrix contained fine collagen fibrils resembling vitreous. We believe that this neoplasm represents a congenital adenoma of the ciliary body and iris. 相似文献