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61.
Abstract Apolipoprotein (apo) A-IV is a protein synthesized, in humans, only by the small intestine. It has a molecular weight of 46 000 Da. This paper summarizes the evidence supporting its role as a satiety factor following the ingestion of fat. This function of apo A-IV is unique and not shared by other apolipoproteins, including apo A-I. The satiety effect of apo A-IV is centrally mediated. The mechanism of how apo A-IV inhibits food intake is not clear but it probably acts by inhibiting both gastric acid secretion as well as gastric motility. Lipid absorption stimulates apo A-IV synthesis and secretion by the jejunum. In addition to lipid feeding, there is evidence that a factor which is released as a result of lipid absorption in the distal small intestine also stimulates the synthesis and release of apo A-IV by the jejunum. This factor is probably PYY. 相似文献
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Guidelines and enabling objectives for training primary healthcare providers,gynecologists and obstetric and gynecology residents in Female Pelvic Floor Medicine and Reconstructive Surgery 下载免费PDF全文
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Douzinas EE Pitaridis MT Patsouris E Kollias S Boursinos V Karmpaliotis DI Gratsias Y Evangelou E Papalois A Konstantinidou AE Roussos C 《Critical care medicine》2003,31(8):2183-2189
OBJECTIVE: The circulatory shock following intestinal ischemia-reperfusion injury has been attributed to hypovolemia. The purpose of the current study is to clarify the pathophysiology of this type of shock and to test the hypothesis that hypoxemic compared with normoxemic reperfusion improves hemodynamics. DESIGN: Randomized animal study. SETTING: Medical school laboratory. SUBJECTS: Twenty-one pigs. INTERVENTIONS: Pigs were subjected to 120 mins of intestinal ischemia by clamping the superior mesenteric artery. Upon declamping, the animals were randomized into two groups: a group that received hypoxemic reperfusion (HR group, n = 8) with a PaO2 = 30-35 and a control group reperfused with PaO2 = 100 mm Hg (control group, n = 13). MEASUREMENTS AND MAIN RESULTS: Measurements included mean arterial pressure, cardiac index, pulmonary artery occlusion pressure, and requirements for fluids and epinephrine. Biopsies from the terminal ileal mucosa were taken for malondialdehyde measurements at baseline, at 120 mins of ischemia, and at 30 and 60 mins of reperfusion. A piece of left ventricle was obtained after 120 mins of reperfusion for histologic studies. Five of 13 animals of the control group died in intractable shock; no animal of the HR group died (p =.11). The decrease in the mean arterial pressure during reperfusion was more pronounced in the control group (p <.008) despite the larger doses of epinephrine administered, compared with the HR group (p <.02). During reperfusion, both groups exhibited a decrease in cardiac index; this was more pronounced in the control group (p =.0007). Pulmonary artery occlusion pressure increased during reperfusion in both groups and was more pronounced in the control group (p =.04 at 60 mins). Although mixed venous blood oxygen saturation of the control animals was higher at 30 mins of reperfusion (p =.005), it declined after 60 mins and became lower than that of HR animals at the end of reperfusion (p <.02). The myocardial histopathologic injury score was higher in the control group (2.0 +/- 0.69 and 3.4 +/- 0.89 for the HR and control groups, respectively; p <.03). The concentrations of intestinal mucosa malondialdehyde were significantly higher in the control group at 60 mins of reperfusion (p <.03). CONCLUSIONS: Acute myocardial ischemia and left heart failure significantly contribute to the circulatory shock that follows intestinal ischemia/reperfusion injury and are attenuated by hypoxemic reperfusion. 相似文献
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C Hughes ; KB Thomas ; P Schiff ; RW Herrington ; EE Polacsek ; KM McGrath 《Transfusion》1988,28(6):566-570
Current standards for the preparation of factor VIII (FVIII) concentrates from human plasma recommend separation of plasma from red cells (RBCs) within 6 hours of blood donation, thereby reducing the volume of plasma from donated whole blood available for processing to FVIII concentrate. The decay of FVIII clotting activity (FVIII:C) in whole blood and plasma stored at 22 and 4 degrees C and the recovery of FVIII:C in cryoprecipitate and FVIII concentrate prepared from plasma separated from whole blood stored overnight at 4 degrees C were investigated. In whole blood stored at 22 degrees C and plasma stored at either 4 or 22 degrees C, 90 percent of the original FVIII:C was present at 6 hours, 80 percent at 12 hours, and 65 to 70 percent at 18 hours. At these times lower levels of FVIII:C were recovered from whole blood stored at 4 degrees C, that is, 84, 68, and 56 percent, respectively. In cryoprecipitates prepared from plasma separated from RBCs after 18 hours' storage at 4 degrees C (18-hour plasma), 43 percent of FVIII:C activity was recovered, as compared with 61 percent recovered from standard plasma separated within 6 hours of donation (6-hour plasma), p less than 0.05. With large-scale preparation of FVIII concentrates, however, the yield of FVIII:C was similar whether 18- or 6-hour plasma was used. Thus FVIII concentrates--but not cryoprecipitates--can be prepared from plasma separated from whole blood stored at 4 degrees C for up to 18 hours without undue loss of potency. 相似文献
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The enhancer-like sequence 3' to the A gamma gene is polymorphic in human populations 总被引:1,自引:0,他引:1
Bouhassira EE; Krishnamoorthy R; Ragusa A; Driscoll C; Labie D; Nagel RL 《Blood》1989,73(4):1050-1053
Cloning and sequencing of the enhancer 3' of the A gamma globin gene of a particularly low G gamma and HbF sickle cell anemia (SCA) patient unexpectedly revealed three base changes (T----C, C----A, and A----G at sites +2285, +2460, and +2676) previously associated with the Seattle- type HPFH, thus leading the authors to suspect that the three mutations were polymorphic. The determination of the incidence of the mutations among various ethnic groups allowed the authors to conclude that this is a widely spread polymorphism, thus excluding any role of these base changes in the determination of the hereditary persistence of fetal hemoglobin (HPFH) phenotype. The origin of these three mutations is not clear because they appear linked, and the same bases (C, A, G) are found in homologous position in the 3' of the normal G gamma gene. As C, A, G at positions +2285, +2460, and +2676 are found with a 100% frequency in African SS patients and presumably among normal Africans (to explain the extremely high frequency among normal American blacks), it is likely that this was the sequence preceding the division of races. The presence of T, C, and A at the same positions apparently occurred after the divergence between blacks and the other races, that is, within the last 1 million years. 相似文献
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