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41.
D Meyer 《SADJ》2005,60(9):386-387
One of the hallmarks of progressive immune deficiency is a steady decline in the absolute number of CD4+ T-lymphocytes. As the immune response thus becomes suppressed, opportunistic systemic infections such as protozoal (Pneumocystis carinii pneumonia, disseminated toxoplasmosis), viral (Cytomegalovirus pneumonitis and colitis and persistent invasive herpes simplex lesions), fungal (cryptococcossis and esophageal candidiasis) and bacterial infections (atypical mycobacterial and extrapulmonary tuberculosis) set in to claim their toll. Ocular complications occur in about 75% of AIDS patients and may be divided into four categories: Retinal microangiopathy, Opportunistic infections, Tumours, Neuro-ophthalmological lesions. Only the most frequently occurring manifestations will be highlighted.  相似文献   
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43.
Using 2D and M-Mode transesophageal short axis cross sections, right ventricular systolic wall motion was quantified in 15 normal patients. A further group of 39 patients with right ventricular infarction was investigated. In the normal group fractional shortening of the septum was -19.6% (-45 to 8%), that of the lateral wall 51.6% (37 to 73%), of the posterior wall 33.9% (5 to 50%) and of the anterior wall 42.7% (18 to 57%). Right ventricular infarction (RVI) was associated in 33 patients with posterior left ventricular infarction (85%) and in three patients with anterior infarction. In two cases only an isolated RVI was found. Right ventricular dilation occurred in 24 patients (61%). Hemodynamic criteria were fulfilled in eleven out of 21 patients (53%). RVI was confirmed in one patient by surgery and in ten patients by autopsy. Recognition of regional wall motion abnormalities by transesophageal echocardiography permits an accurate bedside identification of RVI. 2D and M-Mode registration of the short axis improves RVI assessment. Wall motion analyses offer the possibility to determine the extent of right ventricular infarction.  相似文献   
44.
We documented the risks associated with windsurfing on sewage polluted water. Seventy-nine windsurfers and 41 controls were studied over a nine-day period for occurrence of symptoms of gastroenteritis, otitis, conjunctivitis, and skin infection. Relative risks were 2.9 for occurrence of one or more of these symptoms and 5.5 for symptoms of gastroenteritis. Relative risk increased with the reported number of falls into the water.  相似文献   
45.
Alternative techniques were introduced in the last 20 years for the treatment of gallstones. Among these the extracorporeal shock wave lithotripsy followed by a systemic litholytic therapy represents undoubtedly the most attractive one. A group of two surgeons and two gastroenterologists has started to evaluate this treatment in April 1988, using a piezoceramic lithotryptic system (Piezolith 2300). From April 1988 to May 1989 we have treated 32 patients who fulfilled the selection criteria-symptomatic gallstone disease, 1-3 radiolucent concrements of less than 30 mm of diameter, functioning gallbladder. We noted only one pancreatitis as a complication of this treatment. The overall stonefree rate is 16% after two months, 32% after four months and 56% after six months, depending on the size and number of stones. A definitive evaluation and final conclusion will only be possible when the rate of late recurrences after this treatment will be known.  相似文献   
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47.
Acute ischaemia of the vertebrobasilar circulation leads to a variety of clinical manifestation and is mostly due to cardiogenic or artery-to-artery embolism. We describe four neurological emergency situations involving vertebrobasilar artery aclusion of other origins: basilar migraine, extrinsic compression by rheumatoid inflammatory tissue, generalized vasculitis in subacute rheumatic fever and basilar artery dissection. The differential diagnosis of acute vertebrobasilar artery occlusion may have an important impact on patient management.  相似文献   
48.
The brain is isolated behind a blood-tissue barrier that restricts the access of circulating proteins to neural cells. There is evidence that some of these proteins are synthesized within the central nervous system. The present study examines the synthesis and secretion of such proteins by cultured macroglial cells. Primary glial cultures were derived from cortical and subcortical regions of neonatal rat brains, and subsequent secondary cultures were enriched in type-1 astrocytes, type-2 astrocytes, or oligodendrocytes. Newly synthesized proteins were immunoprecipitated from the culture media using antisera directed against whole rat serum. All three types of glial cells secreted a range of plasma proteins. In general, type-1 astrocytes secreted more of these proteins than did type-2 astrocytes or oligodendrocytes, although the one-dimensional polyacrylamide gel electrophoresis (PAGE) profiles were specific for each cell type. Antisera directed against specific plasma proteins identified three of the most abundant proteins secreted by type-1 astrocytes as transferrin, α-2-macroglobulin, and ceruloplasmin. Northern blot analysis of cellular RNA confirmed that type-1 astrocytes contained transferrin mRNA, and that it was more abundant in cultures derived from subcortical regions than from cortical regions. In situ hybridization studies revealed that virtually all type-1 and type-2 astrocytes contained transferrin mRNA. Since the proteins identified in this study have been proposed to have a variety of neurotrophic roles in the central nervous system, these data further extend the range of possible functions that glial cells may serve in the CNS.  相似文献   
49.
Summary One hundred patients with a verified subarachnoid haemorrhage were studied in a double blind, placebo-controlled trial at a single centre to determine the value and relative risks of tranexamic acid (TXA) in the management of ruptured intracranial aneurysms. The incidence of recurrent haemorrhage between active and placebo groups was identical (12%) and the mortality from recurrent haemorrhage was 7% and 5%, respectively. The overall incidence of cerebral infarction before surgery, at discharge and at 6 months follow-up was greater in the TXA group (27%) than in the control group (11%). Post-operative cerebral ischaemia was significantly more frequent in the active, 18 of 29 as compared to 6 of 32 patients, in the placebo group. In a fifth of the patients in whom cerebral blood flow was estimated there was a significant reduction of cerebral blood flow (CBF) on the side of the ruptured aneurysm in the TXA treated group. It is suggested that this may be the cause of the increased incidence of cerebral ischaemia in this group. There was no significant difference in the incidence of cerebral vasospasm, hydrocephalus, visual disturbances and gastrointestinal disturbances.More fatalities were encountered from ischaemia and recurrent haemorrhage in the TXA group but these differences did not reach statistical significance at the 5% level. Given that disability was due to either vasospasm or recurrent haemorrhage then a patient under TXA treatment was significantly more likely to have disability due to vasospasm (p<0.04); the reverse was true for the placebo patient (p<0.05).  相似文献   
50.
The potential cytoprotective actions of a novel nicotinic agent 2,4-dimethoxybenzilidene anabaseine (DMXB) were investigated in differentiated PC12 cells and transected rat septal cholinergic neurons in vivo. In NGF-differentiated PC12 cells, removal of both NGF and serum led to cell loss, a reduced % of cells expressing neurites, the release of lactate dehydrogenase, and a decrease in total cellular protein. Cell loss was apparent within 24 h, and remained constant between 4–8 days post-NGF removal. NGF alone (100 ng/ml), DMXB (10 μM), but not nicotine (10 μM), prevented these cell and neurite losses. DMXB-induced cytoprotection was blocked by 1 μM mecamylamine. DMXB (1 mg/kg, ip) injected twice but not once per day protected cholinesterase-staining septal neurons from retrograde degeneration following unilateral fimbrial transections. The twice per day DMXB injection-protocol also decreased cell roundness among cholinesterase-staining cells in the lesioned septal hemisphere compared to saline-injected animals. These studies suggest that DMXB may exert cytoprotective activity in NGF-sensitive neuronal populations. © 1994 Wiley-Liss, Inc.  相似文献   
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