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991.
992.
Hepatoblastoma: radiologic-pathologic correlation in 50 cases   总被引:5,自引:0,他引:5  
Fifty cases of hepatoblastoma were reviewed. Virtually all patients were infants or young children with hepatomegaly or a mass. Calcification seen on 11 of 20 radiographs was often in a pattern of small chunks, and eight of these correlated with osteoid formation in histologically mixed hepatoblastomas. Angiography generally showed tumor vascularity, sometimes with a spoke-wheel pattern. Suggestion of tumor nodularity or lobulation on sonography or computed tomography (CT) correlated with the gross appearance. The tumor was usually echogenic and occasionally had small hypoechoic or anechoic areas representing necrosis or hemorrhage. On CT it was usually hypodense, with minimal if any enhancement. The calcification pattern and demonstration of tumor lobulation with septation may help differentiate hepatoblastoma from other liver neoplasms in infants and children under 5 years of age.  相似文献   
993.
994.
995.
Objective: To determine the risk of adverse maternal outcome associated with obstetric intervention in labour.Methods:All cases of macrosomic births conducted at the University of Calabar Teaching Hospital,Calabar,between January 1st 1994 and December 31st 2000 were reviewed.Measure of treatment/intervention effect was calculated as relative risk for adverse maternal outcome,using spontaneous vaginal births as control.Results:Frequency of mode of delivery was as follow: vaginal births,139(60.7%);instrumental vaginal deliveries,16(7%);and abdominal deliveries,74(32.3%).Obstetric intervention occurred in 90(39.3%) cases.Sixty-four(28%) cases did not book for antenatal care,with 42 cases(18.3%) requiring obstetric intervention.About one in every two parturients(1: 2.1) in this study,requiring obstetric intervention at delivery had been interfered with at unorthodox health facilities.Relative risks for postpartum haemorrhage,wound sepsis and paralytic ileus were significantly high in parturients with abdominal delivery;while in parturients with instrumental vaginal delivery relative risks were significantly high for puerperal sepsis,paralytic ileus and obstetric palsy.There were no maternal deaths.Conclusion:Obstetric intervention in parturients with macrosomic births was high due to labour complications;and was associated with significant risk for adverse maternal outcome,especially in parturients with unskilled interference.  相似文献   
996.
Whether the level of terminal deoxynucleotidyl transferase (TdT) activity in mononuclear cells from bone marrow and peripheral blood has prognostic significance has been analyzed prospectively in 164 children with T and non-T, non-B marked acute lymphoblastic leukemia (ALL). TdT was measured at diagnosis to assess its value as a predictor of duration of remission and length of survival. It was measured repeatedly during remission to assess whether it could predict relapse. Ninety-seven percent of the children achieved a complete remission of their disease, and 40% relapsed during the study. The level of TdT activity in blasts at diagnosis varied 1000-fold from patient to patient. There was no statistically significant relationship between TdT activity in cells at diagnosis and the achievement of complete remission, the duration of remission, or length of survival. TdT activity was significantly increased in the bone marrow of 65% of patients at the time of marrow morphological relapse, but was rarely increased in marrow from patients with isolated testicular or central nervous system relapse. Wide fluctuations in TdT activity were characteristically seen in mononuclear cells from the marrow and peripheral blood of patients with ALL at all stages of their disease. An isolated high value of TdT activity in the bone marrow or peripheral blood cannot be taken as evidence of impending relapse. Quantitative measurements of TdT activity alone on mononuclear cells from bone marrow and peripheral blood are helpful in differential diagnosis, but cannot guide therapy of children with ALL.  相似文献   
997.
An assay system has been developed based on automated radiometric quantification of 14CO2 produced through oxidation of [1-14C] fatty acids by mycobacteria. Two stains of M. tuberculosis (H37Rv and Erdman) and one of M. bovis (BCG) in 7H9 medium (ADC) with 1.0 microCi of one of the fatty acids (butyric, hexanoic, octanoic, decanoic, lauric, myristic, palmitic, stearic, oleic, linoleic and linolenic) were studied. Results previously published on M. lepraemurium (Hawaiian) were also included for comparison. Both strains of M. tuberculosis had maximum 14CO2 production from hexanoic acid. Oxidation of butyric and avid oxidation of lauric acids were also found with the H37Rv strain but not with Erdman. In contrast, 14CO2 production by M. bovis was greatest from lauric and somewhat less from decanoic acid. M. lepraemurium showed increasing oxidation rates from myristic, decanoic and lauric acids. Assimilation studies of M. tuberculosis H37Rv confirmed that most of the oxidized substrates were converted into by-products with no change in those from which no oxidation was found. These data suggest that the radiometric measurement of differential fatty acid metabolism may provide a basis of strain identification of the genus Mycobacterium.  相似文献   
998.
This study describes the role of lymphatics in the removal of macrophages from inflammatory lesions in the heart of hypokalemic rats and rats recovering from hypokalemia. The inflammatory lesions are characterized by focal cardiomyocyte necrosis, edema, and mononuclear infiltrate. The vascular and lymphatic capillaries are maintained along with the basement membrane of the necrotic cardiomyocyte. Through prior investigation, it was revealed that refeeding potassium led to a rapid reduction in lesion area. The purpose of the current investigation was to establish the role of the lymphatics as a means of reducing the lesion area by removal of the cellular infiltrate and edema. Using a limited potassium diet, hypokalemic rats were sacrificed via perfusion fixation during the hypokalemic and the potassium re-supplementation periods. Heart tissue was examined by light and electron microscopy. During the hypokalemic period, phagocytic mononuclear cells were found engulfing necrotic cardiac muscle cells. With refeeding of potassium, these phagocytic cells appeared to be diminished in number, a reduction that coincided with a decrease in the lesion size. Lymphatic channels were dilated and full of mononuclear cells. These channels were differentiated from the vascular capillaries by standard morphological criteria. In conclusion, the lymphatics play an important role in the healing process by reducing the lesion size through the removal of phagocytic cells and the uptake of proteinaceous material.  相似文献   
999.
The atherogenic and cholesterolemic effects of animal protein vis-a-vis plant protein are well documented. Virtually all the studies were carried out using diets high in saturated fat, such as coconut oil. In order to determine if the same effects were seen with less saturated fat, we have compared atherogenic effects of an animal protein (casein) with those of a plant protein (soybean protein isolate) fed with partially hydrogenated soybean oil (PHS) (iodine value 72) or soybean oil (iodine value 134) as part of a cholesterol-free semipurified diet. After 6 months only rabbits fed casein-PHS exhibited elevated levels of plasma and liver cholesterol and triglycerides and atherosclerosis. Rabbits fed soy protein-PHS had slightly higher plasma cholesterol and triglycerides than did those fed soy protein and soybean oil, but values in both groups were in the normal range. The different effects of animal and plant protein on lipidemia and atherosclerosis can be influenced by dietary fat and appear to be dependent on fat saturation.  相似文献   
1000.
Nand  S; Sosman  J; Godwin  JE; Fisher  RI 《Blood》1994,83(2):357-360
In this phase I/II study, 9 patients with myelodysplastic syndromes (MDS) were treated with interleukin-3 (IL-3) followed by granulocyte- macrophage colony-stimulating factor (GM-CSF). Each treatment cycle was 28 days long and administered as follows: 1 microgram/kg/d IL-3 on days 1 through 7 and 3 micrograms/kg/d GM-CSF for days 8 through 21, followed by a 7-day rest period. IL-3 dose escalations were planned, but the dose of GM-CSF was fixed. Three patients had refractory anemia, 4 had refractory anemia with ringed sideroblasts, and 2 had refractory anemia with excess blasts. Six patients were dependent on red blood cell transfusions, 1 on platelet transfusions, and 2 on both. The absolute neutrophil count improved in 7 (77%) patients and the platelet count improved in 3 (33%) patients during therapy. Hemoglobin levels were unchanged. A clinically relevant response was seen in only 1 patient with thrombocytopenia, and he received five cycles of therapy. The neutrophil count decreased in 2 patients and the platelet count decreased in 4 patients during treatment. The toxicity of the treatment was significant. In the first cohort of 3 patients, 1 patient developed supraventricular tachycardia and congestive heart failure. In the second group, 1 patient developed progressive granulocytopenia and died of gram-negative septicemia. Because of the disparate toxicity, 3 more patients were treated at the same dose level. One of these experienced a high fever and bone pain requiring hospitalization. Because of these adverse effects, the IL-3 dose was not escalated and all patients received 1 microgram/kg/d for 7 days. We believe that sequential therapy with IL-3 and GM-CSF at these dose levels causes unacceptable toxicity in patients with MDS. The major toxic events occurred during weeks 4 and 5 after starting treatment and may have been primarily caused by GM-CSF therapy. Although neutrophil counts improve in most patients, the effect on red blood cells and platelets is minimal. At present, this form of therapy remains problematic and appears to have a limited potential in the management of MDS.  相似文献   
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