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31.
Field studies on the morbidity of schistosomiasis mansoni were carried out in some rural endemic areas of Northeastern Brazil during the first semester of 1991. These cross-sectional studies were limited to the assessment of the gradient of clinical forms of the disease. The entire population present in a house-to-house survey was examined. Results have shown a reduction in the prevalence rates of the more severe form of schistosomiasis, the hepatosplenic form, when compared with previous similar studies made in the same areas during the 1960s and 1970s. Changes in prevalence rates of the severe clinical forms from the younger to the older age groups were observed.  相似文献   
32.
The prevalence of hypovitaminosis A among children of the peripheral districts of the city of Campinas, S o Paulo, Brazil, was estimated by determining serum retinol levels by High Performance Liquid Chromatography (HPLC) in a sample of 131 children aged between three and ten years, between April 1991 and February 1992. A prevalence of 17.6% and retinol concentrations in the range of 0.35 to 0.70 micromol/L were found (CI=11.1-24.1; 95%), indicating the existence of public health risk Ophthalmological examinations, however, failed to detect any cases of xerophthalmy. Additional characterization of the sample was obtained from 341 children. The per capita income of the average household was surprisingly high for low-income areas. According to FAO-WHO standards, food consumption was adequate only for protein (133.96%). Adequacy levels were low for energy (87.76%) and particularly for vitamin A (66.13%) and iron (42.14%). Height for-age and weight-for-height anthropometric indices revealed that many children were located below -1 standard deviation.  相似文献   
33.
This is an interim analysis of a multicentric trial that took place in 7 Neonatal Units to compare two initial doses of exigenous pulmonary surfactant (100 mg/kg and 200 mg/kg of phospholipids)by using a porcine surfactant for the treatment of very severe Hyaline Membrane Disease. The initial higher dose produced better oxigenation of arterial blood, reducing the time in high oxygen concentrations,while retreatments were necessary in less than half of the infants receiving 200 mg/kg as initial dose. The protocol of this study allowed the administration of additional doses only when FiO(2) was equal or greater than 0.40 instead of > 0.21, as in a large study recently published, where the same initial doses were given. This resulted in more than 40% reduction in the amount of surfactant administered,with apparently similar clinical outcome.  相似文献   
34.
35.
This study deals with adherence to tuberculosis treatment among men and women as well as the disease's links and consequences vis-à-vis life styles and treatment outcomes. The ethnographic study was a component of the Tuberculosis Epidemiological Control Project in the city of Pelotas and aimed to identify the reasons patients failed to complete treatment. Direct ethnographic observations and semi-structured interviews were used. Use of the term "adherence" is justified by the concern for extending to other fundamental factors in addition to the patient's own individual responsibility. This approach fostered an understanding of views towards disease, social dynamics among the various protagonists involved in the disease process, and treatment. Some of the factors considered in adherence to treatment were: socio-demographic characteristics, cultural factors, popular beliefs, the cost-benefit relationship, physical and chemical aspects of the drugs, the physician-patient relationship, and level of family participation in treatment.  相似文献   
36.
Several techniques have been developed to assess the ecotoxicity of contaminated watercourses. Most of these techniques involve chemical alterations of water samples, by diluting it or by adding chelating agents. These changes become particularly severe when assessing the toxicity of samples with very low pH and with high quantities of contaminants. Trying to overcome this problem, a novel toxicity test, specific for acid waters, was previously developed and field validated. The toxicity of acid samples is assessed using the survival time of Ceriodaphnia dubia. During this study, the novel test was applied to a field situation, where an aquatic system is seriously impacted with acid mine drainage. Its efficiency was tested and compared with two classical toxicity tests: the Microtox and the median lethal dilution with C. dubia. The survival time test was performed without adjusting pH and after adjusting pH to a fixed value (pH 2, 3, and 4). At pH 2 and 4 no acceptable results were obtained; at pH 3 it was possible to distinguish the toxicity due to pH from the toxicity due to other toxicants. The test conducted at local pH was able to discriminate toxicity sources only for highly contaminated samples. The toxicity evaluation of acid mine drainage samples was possible neither with the median lethal dilution test nor with Microtox.  相似文献   
37.
In bioassay-guided search for inducible nitric oxide synthase (iNOS) inhibitory compounds from higher plants of South Korea, two beta-carboline alkaloids, 4-methoxy-1-vinyl-beta-carboline (1) and 4,8-dimethoxy-l-vinyl-beta-carboline (2) have been isolated from the cortex of Melia azedarach var. japonica. The structures of these compounds were elucidated on the basis of spectroscopic data. Compounds 1 and 2 showed marked inhibitory activity of iNOS on LPS- and interferon-gamma-stimulated RAW 264.7 cells.  相似文献   
38.
We evaluated children in the first grade of a elementary school using neurological examination. With no previous knowledge of their educational performance, were invited all children attending five classes of the first grade of an elementary public school chosen randomly, in Itatiba / Sao Paulo / Brazil, whose parents assigned a Commitment Term for participation in this research. Children who missed three evaluations in different days or whose parents did not assigned the Commitment Term were excluded. The Traditional Neurological Examination (ENT) (Lefevre, 1972) was applied. It was considered for normal the measurement of the skull circumference, proposed by Diament & Rodrigues (1976), and the application of all ENT items. The data were stored in a database of the Epi6 Program (Epidemiologic Information), and analyzed by percentage calculation and by the chi2 test. The significance level was 0.05. Children evaluated were 124. The ENT results were normal in 87 (70.16%) and altered in 37 (29.83%). Among the alterations, there were observed: light tremor, light muscular hypotonia, speech acquisition delay, macrocephaly, microcephaly, hyperactivity, cranial nerve syndrome, central facial paralysis. One child presented corticospinal tract impairment syndrome of the distal lower extremities.  相似文献   
39.
Loxosceles adelaida spiders (Araneae, Sicariidae) are found near and inside the caves in the Parque Estadual Turistico do Alto Ribeira (PETAR), Sao Paulo, Brazil, which are visited by thousands of tourists every year. Several Loxosceles species are a public health problem in many regions of the world, by causing severe dermonecrosis and/or complement dependent haemolysis upon envenomation. The aim of this study was to characterize the biochemical and biological properties of L. adelaida venom and evaluate the toxic potential of envenomation by this non-synanthropic Loxosceles species. The biological activities of the L. adelaida venom was compared to that of Loxosceles gaucho, a synanthropic species of medical importance in Brazil. L. adelaida venom showed a similar potential to induce haemolysis, dermonecrosis and lethality as L. gaucho venom. L. adelaida crude venom was purified, yielding a 31 kDa component endowed with haemolytic and dermonecrotic activities. In conclusion, we show here that the troglophile Loxosceles species, L. adelaida, commonly found in the complex of caves from PETAR, is potentially able to cause envenomation with the same gravity of those produced by synanthropic species.  相似文献   
40.
The authors report a case of a virilizing adrenal tumor that developed in a 2-year-old child with Beckwith-Wiedemann syndrome (BWS). He had a fetal diagnosis of omphalocele and a history of neonatal adrenal cysts. The importance of prenatal diagnosis of BWS and postnatal follow-up of tumors is discussed. The differential diagnosis of adrenal pathologies occurring in BWS also is reviewed.  相似文献   
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