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81.
Susan D. Ross M.D. Angela DiGeorge B.S. Janet E. Connelly B.S. Gregory W. Whiting B.S Neil McDonnell Pharm.D. 《Pharmacotherapy》1998,18(6):1290-1297
We performed a literature search for all clinical studies reporting outcomes in patients with the acquired immunodeficiency syndrome (AIDS) receiving granulocyte-macrophage colony-stimulating factor (GM-CSF) for any indication. Safety outcomes included human immunodeficiency virus replication, immune status, and frequency of opportunistic infections and neoplasms. Data were synthesized qualitatively. We identified 22 studies (274 patients): 12 addressed AIDS neutropenia, 8 AIDS cancer therapy, and 2 opportunistic infections. Viral burden was assessed by serum p24Ag in 15 studies. Nine reported no change in levels, three net decreases, and three net increases. All studies showing net increases involved patients receiving GM-CSF without a concurrent antiretroviral. The CD4 counts were unchanged in 5 studies, increased in 3, and not reported in 14. The incidence of neoplasms or new opportunistic infections was low. The literature suggests no increased risk of viral replication or clinical deterioration in patients with AIDS who take GM-CSF concurrently with zidovudine. 相似文献
82.
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Ethanol Feeding Causes Inactivation of Both State 1 and State 2 Rat Hepatic Asialoglycoprotein Receptors 总被引:1,自引:0,他引:1
Benita L. Tworek Janet A. Oka Carol A. Casey Paul H. Weigel 《Alcoholism, clinical and experimental research》1997,21(8):1429-1434
Previous studies have shown that ethanol feeding in rats causes inactivation and redistribution of ˜50% of the total asialoglycoprotein receptors (ASGPRs) in hepatocytes (Tworek et al., J. Biol. Chem. 271:2531, 1996), and that two equal populations of hepatic ASGPRs mediate ligand uptake and processing via two functionally different pathways (Weigel in Glycoconjugates: Composition, Structure and Function , Marcel Dekker, 1992, p. 421). The purpose of this study was to determine if ethanol feeding causes preferential inactivation of only one of these two ASGPR populations, which have been designated state 1 and state 2 ASGPRs. The state 2, but not state 1, ASGPRs are inactivated in isolated hepatocytes by a variety of drugs and inhibitors. State 2 ASGPRs can also be inactivated in permeable cells by ATP treatment and then reactivated by treatment with fatty acyl coenzyme As. In the present study, permeable cell assays for state 2 ASGPR inactivation and reactivation were used to assess whether hepatocytes from ethanol-fed rats contain inactive state 2 ASGPRs. The results show that preferential inactivation of one ASGPR population does not occur after ethanol feeding. That inactive ASGPRs could not be reactivated by treatment with palmitoyl-coenzyme A to a greater extent in ethanol-fed versus control cells indicates there is not a larger pool of inactivated state 2 ASGPRs in treated cells. We conclude that ethanol feeding causes equal inactivation of both state 1 and state 2 ASGPRs. Ethanol feeding may represent the first treatment found to inactivate state 1 ASGPRs. 相似文献
84.
85.
The study was performed to assess the ethiological role of bile in acute pancreatitis provoked by closed duodenal loop in rat. In group I a closed duodenal loop was created by method of Nevalainen. A similar operation was performed in group II, but the common pancreatico-biliary duct was ligated just under the liver. In the control group (group C) only the mobilization of duodenum was performed. After 24 hours the mortality rate was 20% in group I, but 0% in group II and C. The amount of ascitic fluid showed significant elevation in group I versus II and group C, and in group II as compared to group C, too. The serum amylase was significantly higher in group I than group II and group C, and in group II was also higher as compared to group C. Serum total protein differed significantly between all groups, while albumin and total calcium were significantly lower in group I than group II, but group II was only slightly reduced versus group C. Histology showed no differences between groups I and II, but both differed significantly from group C. In conclusion bile seems to be an aggressive factor in pathogenesis of acute pancreatitis induced by closed duodenal loop in rat, but other factors may play more important roles. 相似文献
86.
This study is concerned with the nature and distribution of mineral in the gallbladder of a patient with chronic cholecystitis. Light and electron microscopic imaging revealed the mineral to be in the epithelial cells of the mucosa and fibroblasts of the submucosa. In the epithelial cells at the early stages of deposition, mineral was located in the nuclei and throughout the cytoplasm in association with interdigitating cell processes and apical microvilli but was absent in mitochondria. Elemental and electron diffraction analyses indicated the mineral inclusions to be apatite in nature. 相似文献
87.
Roscoe Taylor Jeff Bazelmans Robert Golec Simon Oakes 《Australian and New Zealand journal of public health》1995,19(5):455-459
Abstract: To investigate the distribution of blood lead levels in a sample of Victorian children, and to compare current levels with those from a similar survey in 1979, blood was tested for lead in 252 children (123 under five years) attending Royal Children's Hospital as outpatients and having venepuncture blood samples for medical reasons. Blood lead levels were determined by graphite furnace atomic absorption spectrophotometer. The mean blood lead level was 0.26 μmol/L (5.4 μg/dL). In the under-five age group, the mean was 0.28 μmol/L (5.7 μg/dL). Only 1.6 per cent of this group exceeded the National Health and Medical Research Council action level of 0.72 μmol/L (15 μg/dL). Levels in this age group have declined significantly since 1979, when the mean was 0.54 μmol/L (11.1 μg/dL) and 12.9 per cent exceeded 0.72 μmol/L (15 μg/dL). Average blood lead levels have halved since 1979, with likely contributing factors being reduced exposure from lead in diet, reduced access to lead in paint and reduced lead in ambient air. Children with elevated levels had identifiable risk factors such as pica or exposure to lead-based paint, suggesting the need for ongoing public health action to prevent exposure in these groups. 相似文献
88.
Simon Vinitski Carlos Gonzalez Feroze Mohamed Tad Iwanaga Robert L. Knobler Kamil Khalili John Mack 《Magnetic resonance in medicine》1997,37(3):457-469
Our aim was to develop an accurate multispectral tissue segmentation method based on 3D feature maps. We utilized proton density (PD), T2-weighted fast spin-echo (FSE), and T1-weighted spin-echo images as inputs for segmentation. Phantom constructs, cadaver brains, an animal brain tumor model and both normal human brains and those from patients with either multiple sclerosis (MS) or primary brain tumors were analyzed with this technique. Initially, misregistration, RF inhomogeneity and image noise problems were addressed. Next, a qualified observer identified samples representing the tissues of interest. Finally, k-nearest neighbor algorithm (k-NN) was utilized to create a stack of color-coded segmented images. The inclusion of T1 based images, as a third input, produced significant improvement in the delineation of tissues. In MS, our 3D technique was found to be far superior to that based on any combination of 2D feature maps (P < 0.001). We identified at least two distinctly different classes of lesions within the same MS plaque, representing different stages of the disease process. Further, we obtained the regional distribution of MS lesion burden and followed its changes over time. Neuropsychological aberrations were the clinical counterpart of the structural changes detected in segmentation. We could also delineate the margins of benign brain tumors. In malignant tumors, up to four abnormal tissues were identified: 1) a solid tumor core, 2) a cystic component, 3) edema in the white matter, and 4) areas of necrosis and hemorrhage. Subsequent neurosurgical exploration confirmed the distribution of tissues as predicted by this analysis. 相似文献
89.
90.
Tony Hope Kathleen M. Tilling Kathy Gedling Janet M. Keene Sandra D. Cooper Christopher G. Fairburn 《International journal of geriatric psychiatry》1994,9(2):149-155
‘Wandering’ is one of the most troublesome of behavioural problems in dementia. The term ‘wandering’ covers many different types of behaviour. We examined the hypothesis that the different types of wandering behaviour seen in dementia from a scale using data collected on 83 elderly subjects suffering from either Alzheimer's disease or multiinfarct dementia. We reject the scaling hypothesis. Our data suggest that there are three main categories of wandering behaviour, and that one of these categories is usefully divided into four subcategories. 相似文献