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101.
BACKGROUND: Using the sera from buckwheat (BW)-allergic patients, several putative causative molecules were reported. However, few molecules were determined on the molecular structure. We demonstrated in 2000 that the major allergen with 24 kDa (BW24KD) is a legumin-like storage protein. OBJECTIVE: The aim of this study was to isolate and characterize further a major allergen with 10 kDa by molecular cloning. METHODS AND RESULTS: Buckwheat allergens were identified by immunoblotting analysis using sera from 14 allergic and two nonallergic individuals. We identified a protein with 10 kDa (BW10KD) that reacted with immunoglobulin E (IgE) more strongly than with IgG and IgA in 57% of the allergic patients but not with IgE in nonallergic individuals. Analyses were performed by N-terminal amino acid sequencing and molecular cloning. Physiological significance was assessed by an immunoblotting experiment showing that the reactivity of an allergic patient's serum IgE to BW10KD was competitively inhibited by natural BW extracts. CONCLUSION: Molecular cloning experiments indicated that BW10KD as a BW allergen was a member of the 2S-albumin multigene family.  相似文献   
102.
5-Methoxy-N,N-diisopropyltryptamine (5-MeO-DIPT) is a synthetic orally active hallucinogenic tryptamine derivative, known also as Foxy or Foxy methoxy. However, few studies have examined its effects in vitro. In the present study, we investigated the actions of 5-MeO-DIPT against monoamine neurotransmitter transporters, including the transporters for dopamine (DAT), norepinephrine (NET), and serotonin (SERT), using COS-7 cells heterologously expressing these transporters and rat brain synaptosomes. 5-MeO-DIPT specifically inhibited the uptake of [3H]serotonin (5-HT) by the SERT-expressing COS-7 cells and rat striatal synaptosomes in a high affinity manner at concentrations similar to those for cocaine. The effect was reversible and competitive. 5-MeO-DIPT failed to stimulate reverse transport of [3H]5-HT through SERT, while it prevented the releasing action of methamphetamine. 5-MeO-DIPT induced cell toxicity at high concentrations in COS-7 cells, and it was not influenced by the expression of SERT. These results demonstrated that 5-MeO-DIPT acts as a competitive SERT inhibitor and has an inability to cause reverse transport, underlying its serotonergic actions.  相似文献   
103.
Summary Parasternal two-dimensional and Doppler echocardiography were compared with angiographic, surgical, and postmortem data in 213 patients with various forms of congenital heart disease for its accuracy in determining patency and anatomy of the ductus arteriosus (DA). The age range of the examined patients was from 1 day to 4 years (mean, 7.4 months). Echocardiography was always performed before any invasive procedure. An adequate window for imaging the DA was obtained by parasternal, two-dimensional echocardiography in 209 patients (98%). A persistent ductus arteriosus (PDA) was detected by invasive methods in 79 of 209 patients (38%), and by two-dimensional and Doppler echocardiography in 76 (sensitivity, 96%; specificity, 100%). The echocardiographic and angiographic findings agreed closely as to the duct's morphology. Our technique permits an accurate visualization of the duct in neonates, infants, and small children with various forms of congenital heart disease.  相似文献   
104.
In pregnancy, dehydration produces marked effects on maternal and fetal body water homeostasis including an increase in fetal urinary sodium concentration and excretion. To examine the role of fetal plasma atrial natriuretic factor (ANF) and glomerular ANF receptors in dehydration-induced natriuresis, we compared plasma ANF levels and glomerular ANF binding characteristics in dehydrated and control maternal and fetal sheep. Mean (+/- SEM) maternal and fetal plasma ANF levels in control animals (n = 9) at 132-136 days gestation were 37 +/- 3 pg/ml and 138 +/- 20 pg/ml, respectively. Although mean ANF receptor maximum binding capacities (Bmax) were significantly higher in maternal than in fetal glomeruli (83 +/- 11 vs 34 +/- 12 fmol/mg protein, respectively), the dissociation constants (Kd) for ANF binding were not different (2.7 +/- 0.6 and 3.7 +/- 1.7 x 10(-10) M, respectively). In an additional 9 animals studied after 63 +/- 4 h of water deprivation, maternal plasma ANF levels were significantly lower than in the control group (14 +/- 4 vs. 37 +/- 3 pg/ml), maternal glomerular ANF receptor Bmax values were significantly higher (732 +/- 203 vs. 83 +/- 11 fmol/mg protein), and Kd values were six-fold higher (17.0 +/- 7.1 vs. 2.7 +/- 0.6 x 10(-10) M), although this difference was only marginally significant (p = 0.06). In contrast to the adult, there was a small, nonsignificant decrease in plasma ANF levels and no difference in Bmax or Kd values between the dehydrated and euhydrated fetal animals.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
105.
106.
 A prospective randomized study was conducted to determine the optimal schedule of rhG-CSF (recombinant human granulocyte colony-stimulating factor). A group of 33 lung cancer patients treated with MVP therapy (mitomycin, vindesine, and cisplatin) were randomly assigned to three groups: an early prophylaxis group in which rhG-CSF was initiated on day 2 of the MVP cycle; a late prophylaxis group in which rhG-CSF was initiated on day 8; and a therapeutic group in which rhG-CFS was initiated after the onset of neutropenia. Ten patients who had received MVP therapy without rhG-CSF were also analyzed as a no-support group. The incidence of neutropenia was 80% (16/20 courses) in the early prophylaxis group, 44% (8/18) in the late prophylaxis group, 94% (17/18) in the therapeutic group, and 94% (16/17) in the no-support group. The incidence of neutropenia in the late prophylaxis group was less than in the early prophylaxis group (P<0.05), the therapeutic group (P<0.01), and the no-support group (P<0.01). The late prophylactic rhG-CSF schedule was therefore more effective in countering neutropenia than either the early prophylactic or therapeutic schedule. Received: 13 January 1995 / Accepted: 11 August 1995  相似文献   
107.
Summary An autopsy case of congenital atrioventricular (AV) heart block is described. A newborn infant of a mother with systemic lupus erythematosus died 10 h after birth. Autopsy revealed hematoxylin bodies in the AV node, central fibrous body, and fibrous annulus of the heart. Also, immunoglobulin G (IgG) localization in the hematoxylin bodies was demonstrated by an immunoperoxidase technique. It is suggested that IgG or immune complexes crossed the placenta and that the immune deposition directly injured the cardiac conduction system, causing AV block.  相似文献   
108.
Nonfibrotic pancreases with a nondilated duct are susceptible to pancreatic fistula or leakage following pancreaticoduodenectomy. We developed a novel pancreatic duct-invagination anastomosis using an ultrasonic dissector and applied this technique to 14 consecutive pancreaticoduodenectomies and 1 segmental pancreatectomy for otherwise normal pancreases. With the aid of an ultrasonic dissector, even branch pancreatic ducts were skeletonized, ligated securely, and divided during pancreatic transection. Moreover, the main duct was exposed (> 1 cm) easily by ultrasonic dissection and a small-caliber pancreatic tube was inserted into the duct on the stump. Subsequently, pancreatic duct invagination could be easily done through a 10 G intravenous catheter passed through the gastrointestinal tract. The main duct was anchored to the adjacent serosa, but any pancreatic parenchymal sutures, possibly leading to internal laceration and/or parenchymal ischemia particularly in soft nonfibrotic pancreases, were avoidable during the procedures. All the anastomoses were done within 10 minutes. Only 1 patient (6.7%)developed pancreatic fistula, which resolved spontaneously in 21 days postoperatively. Neither anastomotic leakage nor remnant pancreatitis was seen in this series. Although a prospective, randomized study is needed, this technique may contribute to reduced morbidity after pancreaticoduodenectomy for a nonfibrotic pancreas with a nondilated main duct.  相似文献   
109.
BACKGROUND: Endothelial cells (ECs) are believed to be critical cellular elements responsible for postnatal angiogenesis. Vascular endothelial growth factor (VEGF) stimulates angiogenesis via the activation of KDR/Flk-1 receptor, which is mainly expressed in ECs. Transactivation of KDR/Flk-1 receptor by bradykinin (BK) B2 receptor contributes to the activation of endothelial nitric-oxide (NO) synthase. Therefore, we examined whether transactivation by BK induced angiogenesis. METHODS AND RESULTS: We developed an in vitro model of human coronary artery ECs (HCECs) tube formation on a matrix gel. We demonstrated that BK dose-dependently induced tube formation. Although a lower concentration of BK did not induce tube formation, the combination of a lower concentration of BK and VEGF did. These effects blocked specific inhibitors of VEGF receptor tyrosine kinases (Tki) and NO synthase. In addition, BK induced the tyrosine phosphorylation of KDR/FlK-1 receptor (transactivation), as did VEGF itself. This transactivation was also blocked by Tki. CONCLUSIONS: Transactivation of KDR/Flk-1 by BK through B2 receptor is a potent signaling in angiogenic phenotype in HCECs.  相似文献   
110.
The aim of this study was to investigate the inhibitory effect of xylitol on the growth of and acid production by mutans streptococci in the presence of various dietary sugars, and the relationship between the inhibition and the accumulation of xylitol 5-phosphate (X5P) under strictly anaerobic conditions like those in the deep layers of dental plaque. Xylitol retarded the growth of mutans streptococci in the presence of glucose (G), galactose (Gal), maltose (M), lactose (L) or sucrose (S) as an energy source, though the inhibition of growth on fructose (Fr) was small. Xylitol inhibited acid production by washed cells of Streptococci mutans from G, Gal, M, L or S (12-83% inhibition). S. mutans accumulated X5P intracellularly through activity of the phosphoenolpyruvate-xylitol phosphotransferase system (PEP-xylitol PTS) when they fermented these sugars in the presence of xylitol. However, in the presence of Fr, no inhibition of acid production was observed. In addition, the amounts of X5P during the fermentation of Fr were smaller than those of other sugars in spite of the presence of PEP-xylitol PTS activity. These results suggest that along with the intracellular accumulation of X5P, xylitol decreases the growth and acid production of mutans streptococci in the presence of various dietary sugars except Fr.  相似文献   
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