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91.
92.
目的探讨第一、二鳃弓综合征面部不对称畸形的整形外科矫治方法。方法根据第一、二鳃弓综合征患者临床及X线所示面部双侧不对称情况,采用健侧下颌骨外板去除、颧骨截骨降低;患侧下颌体、颧骨应用健侧下颌骨外板贴附植骨或高密度多孔聚乙烯(Medpor)假体置入等术式,配合颏部水平截骨颏成形术,以缩小面部双侧宽度的差异,矫治颜面不对称畸形。结果共矫治23例,经6个月至3年的术后随访观察,双侧面部宽度差异明显缩小,正面观面部不对称明显改善。结论第一、二鳃弓综合征面部骨骼发育畸形是三维方向的,双侧面骨宽度的差异,是造成正面观面部不对称的重要因素,根据受术者的具体情况,采用以上术式的组合,扩充患侧或同时缩窄健侧骨骼,进行面部骨性支架重建,可以取得良好的矫治效果。  相似文献   
93.
Assessing the capacity of patients to make decisions about their functional problems has substantial ethical, clinical, and financial implications. The growing population of older adults with cognitive impairment either in the community or in long-term care and medical facilities increase the importance of adequately assessing this capacity. This review examines the current approaches to making this assessment, demonstrates how they are incomplete, and considers potential approaches for improving these evaluations. Future research should develop and validate methods to identify patients with impaired capacity to make everyday decisions. These data will supplement functional, cognitive, and medical assessments.  相似文献   
94.
Schick  PK; Wojenski  CM; Bennett  VD; Ivanova  T 《Blood》1996,87(5):1817-1823
There are several species of alternatively spliced fibronectin (FN). One of these, FN EIIIB, is primarily present in embryonic and in proliferating and migrating cells and is believed to be important for cell maturation. We have studied the synthesis, localization, and secretion of this FN isoform in isolated guinea pig megakaryocytes, nonmegakaryocytic bone marrow cells, and platelets. There was 7.5 times more general FN in megakaryocytes than in nonmegakaryocytic cells based on the analysis of equivalent amounts of protein. FN EIIIB was detected by Western blotting in megakaryocytes but not in nonmegakaryocytic cells present in bone marrow. Neither megakaryocytes nor platelets secreted FN EIIIB, while megakaryocytes secreted 25.3% +/- 4.6% general FN and platelets secreted about 61% general FN in response to thrombin. Analysis of immunostained cells by confocal microscopy revealed that FN EIIIB had been redistributed to the surface of megakaryocytes in response to thrombin. Synthesis was studied by metabolic labeling, and megakaryocytes were shown to synthesize FN and FN EIIIB. Thus, megakaryocytes and platelets are among a small number of adult cells and tissues that synthesize and contain FN EIIIB. The expression of FN EIIIB on the megakaryocyte surface may influence migration and maturation.  相似文献   
95.
On May 8–10, 1995, a workshop on chronic inhalation toxicity and carcinogenicity testing of respirable fibrous particles was held in Chapel Hill, North Carolina. The workshop was sponsored by the Office of Pollution Prevention and Toxics, U.S. Environmental Protection Agency (EPA), in collaboration with the National Institute of Environmental Health Sciences (NIEHS), the National Institute for Occupational Safety and Health (NIOSH), and the Occupational Safety and Health Administration (OSHA). The goal of the workshop was to obtain input from the scientific community on a number of issues related to fiber testing. Major issues for discussion were: (i) the optimal design and conduct of studies of the health effects of chronic inhalation exposure of animals to fibers; (ii) preliminary studies which would be useful guides in designing the chronic exposure study; (iii) mechanistic studies which would be important adjuncts to the chronic exposure study to enable better interpretation of study results and extrapolation of potential effects in exposed humans; and (iv) available screening tests which can be used to develop a minimum data set for (a) making decisions about the potential health hazard of the fibers and (b) prioritizing the need for further testing in a chronic inhalation study. After extensive discussion and debate of the workshop issues, the general consensus of the expert panel is that chronic inhalation studies of fibers in the rat are the most appropriate tests for predicting inhalation hazard and risk of fibers to humans. A number of guidances specific for the design and conduct of prechronic and chronic inhalation studies of fibers in rodents were recommended. For instance, it was recommended that along with other information (decrease in body weight, systemic toxicity, etc.), data should be obtained on lung burdens and bronchoalveolar lavage fluid analysis to assist in establishing the chronic exposure levels. Lung burden data are also important for quantifying aspects of risk assessment related to dosimetric adjustments before extrapolation. Although mechanistic studies are not recommended as part of the standard chronic inhalation studies, the expert panel stressed the need for obtaining mechanistic information as far as possible during the course of subchronic or chronic inhalation studies. At present, no single assay and battery of short-term assays can predict the outcome of a chronic inhalation bioassay with respect to carcinogenic effects. Meanwhile, several short-termin vitroandin vivostudies that may be useful to assess the relative potential of fibrous substances to cause lung toxicity/carcinogenicity have been identified.  相似文献   
96.
光照疗法对新生儿红细胞谷胱甘肽还原酶活性的影响   总被引:3,自引:0,他引:3  
作者对光照疗法(光疗)前及光疗后于口服维生素B_2(43例)和不予口服维生素B_2(17例)的黄疸新生儿的红细胞谷胱甘肽还原酶(GR)的活性进行了动态观察。结果显示,接受短期光疗的黄疸新生儿其红细胞GR活性较光疗前的GR活性有显著下降,光疗后予口服维生素B_2可使下降的红细胞GR活性回升,而不予补充维生素B_2者的红细胞GR活性继续下降。光疗的时间越长,红细胞GR活性的下降越明显,补充维生素B_2使红细胞GR活性回复到正常水平所需的时间也越长。短期光疗也可引起体内维生素B_2的降解,导致红细胞GR活性的下降,为避免因红细胞GR活性下降引起的红细胞额外破坏,对接受光疗的黄疸新生儿常规补充维生素B_2的是必要的。  相似文献   
97.
Intestinal schistosomiasis japonica: CT-pathologic correlation   总被引:1,自引:0,他引:1  
  相似文献   
98.
A new mutant, the Eisai hyperbilirubinemic (EHB) rat, shows no inherent expression of the canalicular isoform of the multidrug resistance protein (cMrp) in the liver. It has defective biliary secretion of organic anions such as bilirubin glucuronides, bromosulfophthalein (BSP), cysteinyl leukotrienes, glutathione (GSH) and bile acid sulfate and glucuronides. When rats were injected intravenously with CdCl2, biliary excretion of Cd over 30 min was 0.28% and 0.004% of the total dose in Sprague-Dawley (SD) and EHB rats, respectively. Six SD rats and five EHB rats were fed a diet containing Cd. Bile Cd was detected at the level of 2 ng/20 min in SD rats, but not in EHB rats. There was no significant difference of hepatic Cd concentration between SD and EHB rats. Furthermore, there were no significant differences of renal and intestinal Cd, and hepatic and renal metallothionein (MT) concentrations between the SD and EHB groups. Biliary excretion of reduced-GSH for 20 min was 1.3 ± 0.3 mg and 3.6 ± 0.9 μg in SD and EHB rats, respectively. Our results suggest that hepatobiliary excretion of exogenous Cd is mediated mainly via carrier transport, including a cMrp or GSH carrier, but that the lack of the transport pathway does not contribute to abnormal accumulation of Cd in the liver. Received: 12 August 1996 / Accepted 7 November 1996  相似文献   
99.
The use of item banks and computerized adaptive testing (CAT) begins with clear definitions of important outcomes, and references those definitions to specific questions gathered into large and well-studied pools, or “banks” of items. Items can be selected from the bank to form customized short scales, or can be administered in a sequence and length determined by a computer programmed for precision and clinical relevance. Although far from perfect, such item banks can form a common definition and understanding of human symptoms and functional problems such as fatigue, pain, depression, mobility, social function, sensory function, and many other health concepts that we can only measure by asking people directly. The support of the National Institutes of Health (NIH), as witnessed by its cooperative agreement with measurement experts through the NIH Roadmap Initiative known as PROMIS (www.nihpromis.org), is a big step in that direction. Our approach to item banking and CAT is practical; as focused on application as it is on science or theory. From a practical perspective, we frequently must decide whether to re-write and retest an item, add more items to fill gaps (often at the ceiling of the measure), re-test a bank after some modifications, or split up a bank into units that are more unidimensional, yet less clinically relevant or complete. These decisions are not easy, and yet they are rarely unforgiving. We encourage people to build practical tools that are capable of producing multiple short form measures and CAT administrations from common banks, and to further our understanding of these banks with various clinical populations and ages, so that with time the scores that emerge from these many activities begin to have not only a common metric and range, but a shared meaning and understanding across users. In this paper, we provide an overview of item banking and CAT, discuss our approach to item banking and its byproducts, describe testing options, discuss an example of CAT for fatigue, and discuss models for long term sustainability of an entity such as PROMIS. Some barriers to success include limitations in the methods themselves, controversies and disagreements across approaches, and end-user reluctance to move away from the familiar.  相似文献   
100.
Interleukin-5 has a specific role in various eosinophilic activities. It is the predominant cytokine produces by activated T-lymphocytes isolated from patients with idiopathic hypereosinophilic syndrome. We studied a young patient suffering from idiopathic hypereosinophilic syndrome who presented with Horner's syndrome, peripheral neuropathy and skin ulcers. The IL-5 gene expression by CD4+ T-lymphocytes and the peripheral eosinophil count were raised. The skin ulcers continued to deteriorate despite a swift reduction of the IL-5 gene expression and peripheral eosinophil count following systemic corticosteroid treatment. We suggest that peripheral eosinophilia may not be responsible for the damage in skin lesions and more aggressive treatment may be required.  相似文献   
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