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1.
Calciphylaxis – a topical overview   总被引:3,自引:0,他引:3  
'Calciphylaxis', a calcification syndrome associated with ischaemic cutaneous necrosis, is acquired naturally in humans in disease states. It is a life and limb-threatening complication, usually observed in patients with renal disease and secondary hyperparathyroidism, but known to occur in the absence of renal or parathyroid disease. The reported mortality rate, which ranges from 60-80%, relates to wound infection, sepsis and organ failure. It is a small-vessel vasculopathy, which is estimated to occur in about 4% of haemodialysis patients. Clinically, violaceous, reticulate areas of cutaneous necrosis and eschar may be evident, particularly in the extremities. In addition to the clinical picture, a raised calcium phosphorous product, an elevated parathyroid hormone level, radiographic evidence of vessel and soft-tissue calcification and the finding of mural calcification affecting small arteries and arterioles on histopathology help to confirm the diagnosis of this entity which generally has a poor prognosis. A high index of suspicion and an active multidisciplinary management approach, with rigorous attention to wound care and prevention of sepsis, are vital in the management of these patients. In this overview, we discuss the pathophysiology, clinical features and associations, risk factors, diagnosis and management issues relating to calciphylaxis.  相似文献   
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Gastric mucormycosis involvement is a rare condition that usually occurs in inmunocompromised patients and frequently has a fatal outcome. We report the case of a 73‐year‐old woman admitted to the intensive care unit with severe bleeding after an acute pulmonary disease. Upper endoscopy disclosed wide and deep necrotic ulcers in the body and fundus of the stomach and greenish exudates with the antrum and the duodenum undamaged. Autopsy revealed an invasive mucormycosis and a severe atheromatosis. Several predisposing factors for mucormycosis infection have been reported until now. We postulate that ischemic gastritis could be a predisposing factor for colonization of zygomycete.  相似文献   
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Summary Topographical analysis of cerebral electrical activity was performed in 44 patients with hepatic encephalopathy. These patients were classified in 5 groups according to clinical criteria. Eight healthy subjects were used as a control group. All were studied in an awake, eyes closed, condition and some [Control Group (CG), Group 0 (G0), Group 1 (G1) and Group 2 (G2)] also in an awake, eyes open, condition. The awake, eyes closed, maps showed marked differences in the power spectral density (PSD) of the different bands, when comparing normal subjects with patients with several degrees of hepatic encephalopathy. These differences were related to the degree of clinical involvement, mainly in the alpha and delta PSD bands. The combination of a decreased alpha PSD, increased delta PSD, and decreased mean dominant frequency (MDF) allowed a clear discrimination between the different clinical groups. The differences observed between awake, eyes closed, and awake, eyes open, conditions were especially helpful to discriminate between CG subjects and G0, G1 and G2 patients.  相似文献   
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Lack of expression of the fragile X mental retardation protein (FMRP) results in mental retardation and macroorchidism, seen as the major pathological symptoms in fragile X patients. FMRP is a cytoplasmic RNA- binding protein which cosediments with the 60S ribosomal subunit. Recently, two proteins homologous to FMRP were discovered: FXR1 and FXR2. These novel proteins interact with FMRP and with each other and they are also associated with the 60S ribosomal subunit. Here, we studied the expression pattern of the three proteins in brain and testis by immunohistochemistry. In adult brain, FMR1, FXR1 and FXR2 proteins are coexpressed in the cytoplasm of specific differentiated neurons only. However, we observed a different expression pattern in fetal brain as well as in adult and fetal testis, suggesting independent functions for the three proteins in those tissues during embryonic development and adult life.   相似文献   
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The authors review the policies designed to prevent and deal with animal health emergencies which have been implemented in countries of South America. They describe the evolution of the epidemiological situation of the continent, the new arrangements for international trade in animals and products of animal origin arising from the creation of the World Trade Organization (WTO), and the consequences of such developments for livestock production in South America. Veterinary systems used to prevent and deal with emergencies in the eleven OIE Member Countries on the continent are described, together with emerging problems which confront the Veterinary Services of the continent, namely: exotic diseases, abnormal occurrence of endemic diseases subject to control programmes, faults in food-safety mechanisms, diseases which have an environmental impact, and problems connected with animal welfare. The emergencies which present the greatest risk to South America are foot and mouth diseases, transmissible spongiform encephalopathies, the porcine reproductive and respiratory syndrome, food poisoning, Newcastle disease and fowl plague. Other problems are the appearance of new strains of existing agents, and the presence of resistant individuals among species of bacteria or harmful arthropods. The authors emphasise the need to co-ordinate the prevention of emergencies with development work at the international level, particularly regional and international agreements, harmonization of procedures, progress in animal health and public health, risk analysis, etc. These systems and methods of prevention have a contribution to make in enhancing the potential of animal production in South America, and the adoption of stricter health and quality standards, according to criteria established by the WTO Agreement on the Application of Sanitary and Phytosanitary Measures.  相似文献   
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Visceral leishmaniasis should be suspected in renal transplant recipients in whom a fever develops of unknown origin. A 53-year-old renal transplant recipient developed pyrexia, hepatosplenomegaly, and pancytopenia 4 years after transplantation. Antileishmaniasis serology was negative, and the diagnosis was confirmed through bone marrow examination. Treatment with glucantine (N-methylglucamine antimoniate) led to acute pancreatitis, and treatment with ketoconazole plus allopurinol for 21 days was effective to eradicate Leishmania donovani.  相似文献   
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Due to the absence of easily applicable cut‐off points to determine high blood pressure or hypertension in children, as in the adult population, blood pressure is rarely measured in the pediatrician''s clinical routine. This has led to an underdiagnosis of high blood pressure or hypertension in children. For this reason, the present study evaluate the utility of five equations for the screening of high blood pressure in children: blood pressure to height ratio, modified blood pressure to height ratio, new modified blood pressure to height ratio, new simple formula and height‐based equations. The authors evaluated 1599 children between 5 and 18 years. The performance of the five equations was analyzed using the receiver‐operating characteristics curves for identifying blood pressure above P90th according to the American Academy of Pediatrics Clinical Practice Guideline 2017. All equations showed an area under the curve above 0.882. The new modified blood pressure to height ratio revealed a high sensitivity whereas the height‐based equations showed the best performance, with a positive predictive value above 88.2%. Finally, all equations showed higher positive predictive values in children with overweight or obesity. The height‐based equation obtained the highest PPV values above 71.1% in children with normal weight and above 90.2% in children with overweight or obesity. In conclusions, the authors recommend the use of the height‐based equations equation because it showed the best positive predictive values to identify children with elevated blood pressure, independently of their sex, pubertal and weight status.  相似文献   
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