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排序方式: 共有1829条查询结果,搜索用时 15 毫秒
991.
OBJECTIVES: Practice guidelines support informed or shared decision-making about prostate cancer screening. To compare beliefs across three racial/ethnic categories concerning prostate cancer etiology and risk, screening routines, and shared decision-making, we conducted 12 focus groups. METHODS: Participants were recruited in primary care settings and included 33 African Americans, 35 Hispanics, and 22 non-Hispanic Whites. Of the 90 participants, 53% were male. RESULTS: Groups identified heredity, age, race, sexual activity, and other lifestyle influences as risk factors. Few were aware that prostate cancer is asymptomatic in early stages. Confidence in knowledge of screening routines was high, but included misconceptions supporting initiation of screening at earlier ages and at shorter intervals than professional recommendations. Females encouraged screening of male relatives to protect their health. DISCUSSION AND CONCLUSION: While racial/ethnic groups had similar views and knowledge about screening, African Americans wanted to organize to address the threat of prostate cancer in their communities. Hispanics had awakening awareness of the health risks of prostate cancer. Non-Hispanic Whites were aware of the health threat of prostate cancer, but their approach to health protection was more individual and less community focused than that of African Americans. Participants were not aware of controversy about screening. PRACTICE IMPLICATIONS: Developers of educational materials to support informed or shared decision-making should be aware that initial views of prostate cancer screening are positive. 相似文献
992.
We have solved the NMR solution structure of domain III from the Omsk hemorrhagic fever virus envelope protein and report the first sequencing of the Guriev strain of this virus. Important structural differences between tick-borne flaviviruses, such as OHFV and TBE, and mosquito-borne flaviviruses, such as West Nile virus, are discussed. 相似文献
993.
Expression of the multidrug transporter MRP2 in the blood-brain barrier after pilocarpine-induced seizures in rats 总被引:2,自引:0,他引:2
Multidrug resistance proteins (MRPs; symbol ABCC) are membrane glycoproteins that mediate the ATP-dependent export of a wide range of substrates from cells and thereby affect the bioavailability and disposition of many drugs. MRP2 (ABCC2) is expressed on the apical domain of hepatocytes, enterocytes of the proximal small intestine, and proximal renal tubular cells, but its location in the brain is a matter of debate. Most previous studies failed to determine MRP2 mRNA or protein in the brain or cell preparations from the brain of different species including humans. Based on our previous experience with the drug efflux transporter P-glycoprotein, we evaluated whether the immunohistochemical determination of MRP2 expression is sensitive to fixation and staining variables. Furthermore, we examined whether the MRP2 protein is overexpressed after experimentally induced seizures in rats, using the pilocarpine model of temporal lobe epilepsy. The MRP2 expression in the liver was used as positive control. MRP2 deficient TR- rats were used as negative controls. Despite various modifications in tissue fixation and immunohistochemical staining as well as use of different commercially available MRP2 antibodies, we never observed any unequivocal MRP2 staining in the brain of normal rats. However, after a pilocarpine-induced convulsive status epilepticus, clear MRP2 staining became visible in brain capillary endothelial cells and, less frequently, perivascular astroglia and neurons in various brain regions. In view of our recent data on brain access of antiepileptic drugs in MRP2 deficient TR- rats, seizure-induced over-expression of MRP2 in the blood-brain barrier is likely to impair drug penetration into the brain, thereby contributing to drug resistance in epilepsy. 相似文献
994.
Volk HA Arabadzisz D Fritschy JM Brandt C Bethmann K Löscher W 《Neurobiology of disease》2006,21(3):633-646
The disabling seizures associated with mesial temporal lobe epilepsy (TLE) are often resistant to antiepileptic drugs (AEDs). The biological basis of this refractoriness is unknown but may include alterations in AED targets in the epileptogenic brain tissue, reduced AED penetration to the seizure focus, and neuropathological brain alterations such as hippocampal sclerosis typically found in patients with refractory TLE. In the present study, we used a rat model of TLE to examine whether AED responders differ from non-responders in their structural alterations and GABA(A) receptor characteristics in the hippocampal formation. In this model, spontaneous recurrent seizures develop after a status epilepticus induced by prolonged electrical stimulation of the basolateral amygdala. The frequency of these seizures was recorded by continuous video/EEG monitoring before, during, and after daily treatment with phenobarbital, which was given at maximum tolerated doses for 2 weeks. Based on their individual response to phenobarbital, rats were grouped into responders and non-responders. The severity or duration of the initial brain insult (the status epilepticus) did not differ between responders and non-responders, indicating that the difference between the two subgroups is genetically determined. Subsequent histological examination showed a significant loss of neurons in the CA1, CA3c/CA4, and dentate hilus of non-responders, whereas responders did not differ in this respect from non-epileptic controls. The morphological alterations in the non-responders were associated with striking alterations in autoradiographic imaging of diazepam-sensitive and diazepam-insensitive GABA(A) receptor binding in the dentate gyrus with a significant shift to enhanced diazepam-insensitive binding. The present data indicate that neurodegeneration and associated GABA(A) receptor changes in the dentate gyrus are critically involved in the mechanisms underlying refractoriness of seizures in TLE. 相似文献
995.
996.
Schoenbein C Docke WD Wolk K Belbe G Hoflich C Jung M Grutz G Sterry W Volk HD Asadullah K Sabat R 《Clinical and experimental immunology》2008,151(2):306-316
Interleukin (IL)-10 is one of the most crucial immunoregulatory cytokines. Its short-term effects have been analysed extensively, but little is known about its long-term effects. This is of considerable importance, as high systemic IL-10 levels are present for long periods in patients with persistent viral infections, certain cancers and in critical care patients. Our study investigated the effects of the long-term presence of IL-10 on human peripheral blood monocytes. In vitro, IL-10 treatment of these cells for 7 days induced the development of a novel cell type characterized by unique phenotypical and functional characteristics. These cells showed high HLA-DR expression and low expression of CD86 and other co-stimulatory molecules on their surface. The mRNA levels of both HLA-DR and CD86 were high, but no intracellular accumulation of CD86 protein was observed. With respect to its function, these cells showed strongly diminished tumour necrosis factor-alpha production following lipopolysaccharide stimulation, strongly diminished allogenic CD4(+) T cell stimulatory capacity, and even induced a hyporesponsive state in CD4(+) T cells. The phenotype remained stable despite the removal of IL-10. In vivo, we found monocytic cells from patients exhibiting this phenotype after long-term IL-10 exposure. These results complement our knowledge further about the biological effects of IL-10 and may provide an explanation for the sustained immunodeficiency in cases of the persistent presence of systemic IL-10. 相似文献
997.
Okamura N; Malawista SE; Roberts RL; Rosen H; Ochs HD; Babior BM; Curnutte JT 《Blood》1988,72(2):811-816
Activation of 32P-loaded neutrophils with phorbol myristate acetate causes the labeling of a family of three 48K proteins that focus near neutral pH. The relationship between these phosphoproteins and the activation of the respiratory burst has been supported by the previous finding that phosphorylation was defective in the two most common types of chronic granulomatous disease (CGD): X-linked cytochrome-negative (X/-) and autosomal cytochrome-positive (A/+). In this report, these studies have now been extended to the rare A/- and X/+ forms of the disease. In all three patients with A/- CGD examined, the two most acidic 48K proteins failed to undergo enhanced phosphorylation in response to phorbol stimulation, a finding similar to that seen in X/- patients. In contrast, neutrophils from two patients with X/+ CGD appeared to phosphorylate the neutral 48K proteins in a normal fashion. It thus appears that the different phosphorylation patterns seen in chronic granulomatous disease are a reflection of the genetic heterogeneity of this disorder. These findings lend further support to the conclusion that the 48K phosphoprotein family is related to the respiratory burst, although not necessarily in a straightforward manner. 相似文献
998.
Normal brachial plexus: MR imaging 总被引:6,自引:0,他引:6
Magnetic resonance (MR) imaging of the brachial plexus was performed in the axial, coronal, and sagittal planes in seven volunteers. Normal structures were delineated by comparison with axial and sagittal cadaver sections and with gross dissection. Differentiation of soft tissues with MR imaging enabled the brachial plexus to be defined from surrounding muscle and vascular structures. Multiplanar imaging demonstrated anatomic detail not previously demonstrated with other radiologic modalities and provided excellent delineation of the components of the brachial plexus from the ventral rami to the peripheral nerve branches. 相似文献
999.
Limbic encephalitis: two cases 总被引:3,自引:0,他引:3
J. Kohler A. Hufschmidt L. Hermle B. Volk C.H. Lücking 《Journal of neuroimmunology》1988,20(2-3):177-178
1000.