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101.
A murine hybridoma clone is described that grows continuously in culture and produces a monoclonal antibody we have called Royal Free Monoclonal Antibody to factor IX No. 1 (RFF-IX/1). This has high affinity for a coagulation site on factor IX. RFF-IX/1 immobilised on sepharose can be used to deplete factor IX from normal human plasma. This immunoaffinity depleted plasma is indistinguishable from severe Christmas disease plasma and can be used as the substrate in a one stage coagulation assay for factor IX. The affinity column has high capacity and can be regenerated so that large scale production from normal plasma of factor IX deficient plasma as a diagnostic reagent is now feasible.  相似文献   
102.
Hasan  AA; Cines  DB; Ngaiza  JR; Jaffe  EA; Schmaier  AH 《Blood》1995,85(11):3134-3143
An important biologic function of high-molecular-weight kininogen (HK) is to deliver bradykinin (BK) to its cellular receptors. Internalization and degradation of HK may provide a mechanism by which endothelial cells modulate the production of BK and control its activities. Therefore, we investigated the binding and subsequent distribution of biotinylated-HK (biotin-HK) associated with human umbilical vein endothelial cells (HUVEC). HUVEC bound 3 to 4 times more HK and with greater avidity at 1 to 3 hours at 37 degrees C than at 4 degrees C (Bmax = 1.0 +/- 0.02 x 10(7) molecules/cell, kd = 7 +/- 3 nmol/L v Bmax = 2.6 +/- 0.2 x 10(6) molecules/cell, kd = 46 +/- 8 nmol/L). However, there was no evidence that the difference was caused by internalization of HK at the higher temperature. First, the same amount of biotin-HK was associated with nonpermeabilized and permeabilized HUVEC using buffers containing 20 to 50 mumol/L zinc ion in the absence or presence of 2 mmol/L calcium ion. Second, binding of biotin-HK to HUVEC was approximately 92% reversible at 1 hour when the cells were maintained at both 37 degrees C and 4 degrees C. Third, neither chloroquine nor primaquine altered the amount of biotin-HK bound to HUVEC. Fourth, biotin-HK bound to HUVEC was almost completely removed by pronase. Fifth, the nonpermeable dye, crystal violet, almost completely quenched the fluorescence signal emitted by HUVEC-associated fluorescein isothiocyanate (FITC) HK. Finally, the localization of HUVEC-bound FITC-HK was restricted to the membrane as shown by laser scanning confocal microscopy. The expression of HK binding sites had an absolute requirement for metabolic energy, but was not dependent on new protein synthesis. Membrane-bound HK contributed to the anticoagulant nature of endothelial cells by blocking human alpha-thrombin binding and its resultant induction of prostacyclin formation. These studies indicate that HK is not internalized by HUVEC, but remains primarily on cell surfaces to be accessible for BK liberation and to modulate the binding and actions of alpha-thrombin.  相似文献   
103.
Thirteen behavioral variables from six tasks were measured in alcohol-preferring (AA, FH, and P) and -non-preferring (ANA, FRL, and NP) rat lines/strains and subjected to Factor Analysis. Four independent factors accounted for >90% of the variance. Defecation in the open field and ultrasonic vocalizations after an air puff were negatively correlated with alcohol intake and preference, whereas the increase in daily fluid intake in the presence of saccharin was positively correlated. Other factors could be labeled Activity, Emotionality, and Immobility Factors, and each was independent of the Alcohol Factor. When an additional alcohol-preferring rat line (HAD) and two additional non-preferring groups (LAD and ACI) were tested, they were found to differ on most behaviors that were associated with alcohol intake and preference in the Factor Analysis: vocalizations and saccharin-induced increase in fluid intake, but not defecation. A new Factor Analysis was then performed incorporating these three new groups and including five new behavioral measures. The following measures had high loadings on the Alcohol Factor: alcohol intake under choice conditions; alcohol preference; forced alcohol intake; alcohol acceptance (forced alcohol intake/basal water intake × 100); ultrasonic vocalization; saccharin intake; saccharin-induced increase in daily fluid intake; defecation in the open field test; and immobility in a modified forced swim test. These findings indicate that there are indeed certain behavioral characteristics that are common among alcohol-preferring rat lines/strains, but there are also substantial group differences on other behavioral measures. For those behavioral measures reflecting emotionality (defecation and ultrasonic vocalization) that loaded highly on the Alcohol Factor, the alcohol-preferring rats had lower scores.  相似文献   
104.
Schmaier  AH; Smith  PM; Purdon  AD; White  JG; Colman  RW 《Blood》1986,67(1):119-130
High mol wt kininogen (HMWK), the major cofactor-substrate of the contact phase of coagulation, is contained within and secreted by platelets. Studies have been performed to localize platelet HMWK in both the unstimulated and activated platelet and to ascertain the effect of platelet enzymes on HMWK itself. On platelet subcellular fractionation, platelet HMWK was localized to alpha-granules, and platelets from a patient with a deficiency of these granules (gray platelet syndrome) had 28% normal platelet HMWK. Platelet HMWK, in addition to being secreted from the platelet, was also localized to the surface of the platelet when activated. Using a competitive enzyme- linked immunosorbent assay for HMWK as an indirect antibody consumption assay, the external membrane of thrombin-activated platelets as well as the releasate from these stimulated platelets had 17 ng HMWK antigen/10(8) platelets available, whereas unstimulated platelets and their supernatant had only 4.9 and 4.2 ng HMWK/10(8) platelets present, respectively. The anti-HMWK antibody consumption by activated normal platelets was specific for membrane-expressed platelet HMWK, since activated platelets from a patient with total kininogen deficiency did not adsorb the anti-HMWK antibody. Enzymes in the cytosolic fraction of platelets cleaved 125I-HMWK (mol wt 120,000) into a mol wt 100,000 polypeptide as well as smaller products at mol wt 74,000, mol wt 62,000, mol wt 47,000, and a few components below mol wt 45,000. No cleavage products were observed when DFP and leupeptin were present. The cleavage of HMWK was specifically prevented by inhibitors of calcium-activated cysteine proteases (leupeptin, N-ethylmaleimide, iodoacetamide, and EDTA) but not by inhibitors of serine proteases (DFP, benzamidine, soybean trypsin inhibitor, or aprotinin). Platelet cytosol increased the coagulant activity of exogenous purified HMWK with maximum HMWK coagulant activity (35-fold) occurring within ten minutes of exposure to platelet cytosol. Treatment of platelet cytosol with leupeptin prevented the increase in the coagulant activity of exogenous HMWK. These studies indicate that activated platelets express platelet HMWK on their external membrane and platelet enzymes can cleave and increase the coagulant activity of exogenous HMWK.  相似文献   
105.
Human myeloperoxidase gene expression in acute leukemia   总被引:2,自引:0,他引:2  
Zaki  SR; Austin  GE; Swan  D; Srinivasan  A; Ragab  AH; Chan  WC 《Blood》1989,74(6):2096-2102
  相似文献   
106.
The present studies sought to elucidate the role of 5-HT2A receptor antagonists in suppressing alcohol intake by comparing the effects of amperozide and FG 5974 on alcohol, food, and water intake in strains of alcohol-preferring rats: P, Alko Alcohol (AA), and Fawn-Hooded (FH). Both amperozide and FG 5974 have 5-HT2A receptor antagonist properties, but FG 5974 also shows presynaptic 5-HT1A receptor agonist activity. After establishment of stable baselines for intake measures in a two-bottle continuous access paradigm, rats ( n = 10) were injected with 1 of 5 doses (0, 1.0, 2.5, 5.0, and 10.0 mg/kg, sc) of amperozide or FG 5974 at weekly intervals. Amperozide dose-dependently reduced alcohol intake, total fluid intake, and alcohol preference in all three strains under continuous access conditions, whereas FG 5974 was less effective. Food intake was also suppressed by amperozide at higher doses, whereas it was increased by FG 5974. Amperozide also dose-dependently reduced alcohol intake when it was available for only 1 hr/day, but FG 5974 tended to increase it. After oral administration, amperozide was also more effective than FG 5974 in reducing alcohol intake. Despite these differences in efficacy in suppressing alcohol intake, both compounds produced taste aversion to a novel saccharin solution. These complex findings suggest that biochemical properties other than 5-HT2A receptor antagonism (e.g., 5-HT1A receptor agonism) may be involved in the effects of amperozide and FG 5974 on alcohol intake and other consummatory behaviors.  相似文献   
107.
AIM: To assess lung parenchymal changes in ankylosing spondylitis (AS) using high resolution computed tomography (HRCT). METHODS: We included 78 AS patients whose average age was 33.87 (18-56) years with a ratio of 53 males to 25 females who were followed up for 3.88 (1-22) years on average. neumonia and tuberculosis were excluded. In a detailed examination of lung HRCT findings, we investigated the presence of parenchymal micronodules,parenchymal bands, subpleural bands, interlobular and intralobular septal thickening, irregularity of interfaces,ground glass opacity, consolidation, mosaic pattern,bronchial wall thickening, bronchial dilatation, tracheal dilatation, pleural thickening, emphysema, thoracic cage asymmetry, honeycomb appearance, structural distortion, apical fibrosis and other additional findings.RESULTS: In detailed HRCT evaluations, lung parenchymal changes were found in 46 (59%) of all patients. We found parenchymal bands in 21 (27%) cases, interlobular septal thickening in 9 (12%), emphysema in 9 (12%), apical fibrosis in 8 (10%), ground-glass opacities in 7 (9%), parenchymal micronodules in 5 (6%), irregularity in interfaces in 3 (4%), bronchial dilatation in 3 (4%), mosaic pattern in 2 (3%), pleural thickening in 2 (3%), consolidation in 1 (1%), bronchial wall thick ening in 1 (1%) and a subpleural band in 1 (1%) case. Furthermore, we detected subsegmental atelectasis in 2 patients and a cavitary lesion in 1 patient. CONCLUSION: Our study had the highest number of AS cases of all previous studies in evaluating lung paren chymal changes. The rate of lung parenchymal changes was slightly lower than that reported in recent literature.  相似文献   
108.
109.
ObjectiveWhile a Mediterranean dietary pattern (MedDiet) has been associated with favorable changes in several features of metabolic syndrome (MetS), its impact on plasma adipokine concentrations remains largely unknown. The objective of this study was to determine the impact of the MedDiet consumed under controlled feeding conditions, without (? WL) and with weight loss (+ WL), on plasma adipokine concentrations in adult men with MetS (NCEP-ATP III).Materials/MethodsThe diet of 26 men with MetS (age 24 to 62 yrs) was first standardized to a North American control diet for 5 weeks. Participants then consumed a pre-determined MedDiet for 5 weeks. Both diets were consumed under weight-maintaining isoenergetic feeding conditions. Participants then underwent a 20-week free-living caloric restriction period, after which they consumed the MedDiet again in weight stabilizing, isoenergetic feeding conditions.ResultsBody weight was reduced by 10.2% ± 2.9% and waist circumference by 8.6 ± 3.3 cm after the weight loss period and stabilization on MedDiet (P < 0.001). MedDiet ? WL had no impact on plasma concentrations of leptin, plasminogen activator inhibitor-1, resistin, visfatin, acylation stimulating protein and adiponectin. MedDiet + WL reduced plasma leptin concentrations (P < 0.01) and increased plasma adiponectin concentrations (P < 0.05) compared with the control diet and MedDiet ? WL.ConclusionData from this nutritionally controlled study suggest that short-term consumption of MedDiet has little effect on the concentrations of many adipokines in the absence of weight loss.  相似文献   
110.
There is an overlap between alcoholism and depressive disorders.However, alcoholics tend to be resistant to the effects of cholinergicagonists, whereas depressives tend to be more sensitive. A recentlydeveloped animal model of depression which is more sensitiveto cholinergic agonists is also more sensitive to the acuteeffects of ethanol. These consistent human and animal studiessuggest that cholinergic challenges may be helpful in separatingalcoholics from depressives.  相似文献   
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