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991.
alpha-fetoprotein-producing adenocarcinoma of the digestive organs (APAD) is known to show a poor prognosis. To clarify the characteristics of chemoresistance in APAD, three proteins of fluoropyrimidine chemotherapy association [dihydropyrimidine dehydrogenase (DPD), thymidine phosphorylase (TP) and thymidylate synthase (TS)] and one protein of cisplatin association [metallothionein (MT)] were immunohistochemically evaluated. Tissue samples were taken from 12 AFP-positive gastric cancers and 94 AFP-negative gastric cancers. Four AFP-positive cancer xenografts (one colonic, two pancreatic, and one biliary tract) and 17 AFP-negative cancer xenografts were also examined. In gastric cancers, high expression of TP was observed in 30% of AFP-negative tumors but in none of AFP-positive tumors (p=0.03). High expression of MT was found in 30% of AFP-negative tumors but in only one of the AFP-positive tumors. The TP-low and MT-low phenotype was noted in 92% of AFP-positive tumors and in 46% of AFP-negative tumors (p=0.004). None of the AFP-positive cancer xenografts revealed high TP expression and only one showed high MT expression. In the cellular level, TP and MT were scarcely co-expressed with AFP in either gastric cancer or xenograft series, using double immunostaining and serial sectioning techniques. There were no significant differences in the expression of DPD and TS between AFP-positive group and -negative group. However, DPD was frequently co-expressed with AFP in poorly differentiated medullary areas of the AFP-positive gastric cancers. The data presented herein suggest that APAD should be sensitive to cisplatin, but resistant to capecitabine and 5'-deoxyfluorouridine, fluoropyrimidines which are converted to 5-fluorouracil by TP. S-1, a fluoropyrimidine containing a strong DPD inhibitor, may be effective for AFP-positive gastric cancers with poorly differentiated medullary growth pattern.  相似文献   
992.
993.
1 Proteinase-activated receptor-2 (PAR2), a receptor activated by trypsin and tryptase, is abundantly expressed in the gastrointestinal tract including the C-fiber terminal, and might play a role in processing of visceral pain. In the present study, we examined and characterized the roles of PAR2 in pancreatitis-related abdominal hyperalgesia/allodynia in mice. 2 Caerulein, administered i.p. once, caused a small increase in abdominal sensitivity to stimulation with von Frey hairs, without causing pancreatitis, in PAR2-knockout (KO) mice, but not wild-type (WT) mice. 3 Caerulein, given hourly six times in total, caused more profound abdominal hyperalgesia/allodynia in PAR2-KO mice, as compared with WT mice, although no significant differences were detected in the severity of pancreatitis between the KO and WT animals. 4 The PAR2-activating peptide, 2-furoyl-LIGRL-NH(2), coadministered repeatedly with caerulein six times in total, abolished the caerulein-evoked abdominal hyperalgesia/allodynia in WT, but not PAR2-KO, mice. Repeated doses of 2-furoyl-LIGRL-NH(2) moderately attenuated the severity of caerulein-induced pancreatitis in WT animals. 5 Our data from experiments using PAR2-KO mice provide evidence that PAR2 functions to attenuate pancreatitis-related abdominal hyperalgesia/allodynia without affecting pancreatitis itself, although the PAR2AP applied exogenously is not only antinociceptive but also anti-inflammatory.  相似文献   
994.
Inflammation, closely associated with obesity, is emerging as an important risk factor for the pathophysiological development of atherosclerosis and diabetes mellitus. Fat balance is critical in the aetiology of obesity. Lipoprotein lipase is an important enzyme in lipid metabolism. The aim of this study was to investigate the long-term effect of the lipoprotein lipase activator, NO-1886, on inflammation cytokines, adiposity and related diseases in miniature pigs fed a high-fat/high-sucrose/high-cholesterol diet (HFSC diet). Chinese Bama-miniature pigs were fed a control diet or HFSC diet with or without NO-1886 for 5 months. The levels of inflammation-associated cytokines were determined using the antibody arrays. Feeding of the HFSC diet to miniature pigs markedly increased the expression of inflammatory cytokines. On the other hand, supplementation of NO-1886 to HFSC diet decreased the expression of inflammatory cytokines significantly, protecting against the development of atherosclerosis and diabetes mellitus. NO-1886 may have a beneficial effect on the most inflammation-associated cytokines, and this effect may contribute to improving atherosclerosis and diabetes mellitus.  相似文献   
995.
Several low molecular weight nonpeptide compounds having the dipicolylamine-zinc(II) complex structure were identified as potent and selective antagonists of the chemokine receptor CXCR4. These compounds showed strong inhibitory activity against CXCL12 binding to CXCR4, and the top compound exhibited significant anti-HIV activity. Zinc(II)-dipicolylamine unit-containing compounds proved to be useful and attractive lead compounds for chemotherapy of these diseases as nonpeptide CXCR4 antagonists possessing the novel scaffold structure.  相似文献   
996.
The metabolism of N-benzylpiperazine (BZP), a recently scheduled designer drug, in the rat has been studied by analyzing its urinary metabolites. p-Hydroxy-BZP (p-OH-BZP) was unequivocally identified as the main metabolite along with a minor metabolite m-hydroxy-BZP (m-OH-BZP), using gas chromatography-mass spectrometry and high-performance liquid chromatography-electrospray ionization mass spectrometry (LC-ESI MS). The time-course excretion profiles of BZP, p-OH-BZP, and m-OH-BZP in the rats were investigated after a single intraperitoneal dosing of 5 mg/kg BZP, by using an optimized analytical procedure that combines solid-phase extraction and LC-ESI MS determination. The cumulative amounts excreted within the first 48 h were approximately 25% for p-OH-BZP and 2% for m-OH-BZP, whereas 6.7% dose of the parent drug BZP was excreted unchanged within 36 h post-dosing. The concentration ratio of p-OH-BZP to m-OH-BZP was 11.6 in the first 4 h, but it increased to 22.7 in 48 h with the elapsed time post-dosing. Most of p-OH-BZP was excreted in urine within approximately 36 h post-dosing, with approximately 50% appearing as the glucuronide conjugate. The present results suggest that p-OH-BZP is the most relevant metabolite to be detected for the proof of BZP intake in the forensic and clinical analysis of human urine.  相似文献   
997.
The present study was undertaken to clarify the epileptogenic activity induced by intracerebroventricular injection (i.c.v.) of antibiotics effective in methicillin-resistant Staphylococcus aureus (MRSA) in chronically electrode implanted rats. Teicoplanin (10-100 microg, i.c.v.) caused dose-related electroencephalographic (EEG) seizure characterized by an uninterrupted high voltage and wave complex. At the same time, the rats showed forelimb clonus, head nodding, jumping and severe convulsion. At a high dose (100 microg, i.c.v.), the drug caused a severe twisting immediately after the intracerebroventricular injection (i.c.v.) followed by jumping and violent convulsion with a continuous rhythmic spike and wave complex in EEG. On the other hand, vancomycin (30-1000 microg, i.c.v.) caused no or almost no epileptogenic activity in terms of behavior and in EEG. However, at a high dose (1000 microg, i.c.v.), the drug caused an occasional spike from the hippocampus without showing any behavioral changes in the rats. Fosfomycin (30-1000 microg, i.c.v.), cefazolin (10-100 microg, i.c.v.) and penicillin G (30-300 microg, i.c.v.), used as reference drugs, caused dose-dependent epileptogenic activity in both EEG. From these findings, it was found that teicoplanin caused a potent epileptogenic activity, different to vancomycin. Therefore, it can be concluded that vancomycin may be safety on epileptogenic activity used for the clinical purpose of infections caused by MRSA.  相似文献   
998.
The non-immune phage antibody library system is one of the most attractive technologies available to current therapeutic, diagnostic and basic scientific research. This system allows the rapid isolation of antibodies of interest that could subsequently be applied directly to drug delivery systems and antibody therapy. Previously, we reported the primer sets to encompass the antibody repertoire and thus improve library quality. However, a wide number of varying primer sets cause to decrease the amplification efficiency of antibody genes. In the present study, we re-generated the library primer sets newly and constructed an improved library from non-immune mice that was far superior in terms of variety and quality. This new library contained 2.4 billion independent clones. In addition, we optimized the selection step from this library to isolate high-affinity antibodies. The optimization of an affinity panning protocol by the incorporation of an automated Microfluidics instrument led to the successful isolation of three different monoclonal antibodies for human vascular endothelial growth factor receptor 2 (KDR). These antibodies were demonstrated to exhibit high specificity and were able to detect a mere 0.6 fmol of KDR by dot blot analysis. Previously reported antibodies for luciferase were also isolated successfully from this library. Our results clearly demonstrate the importance of the improved protocol for the library preparation of antibodies and the resulting isolation of antibodies for clinical and research applications.  相似文献   
999.
OBJECTIVE: To assess the effects of a combination of fenofibrate and losartan on the plasma concentrations and urinary excretion of purine bases in healthy male subjects. METHODS: 5 healthy males participated in a fenofibrate plus losartan combination study. The plasma concentrations and urinary excretion of purine bases (hypoxanthine, xanthine, uric acid) were measured before and after administrations of losartan (100 mg o.d.) alone for 2 weeks, losartan and fenofibrate together for 2 weeks and fenofibrate (300 mg o.d.) alone for 2 weeks, which were given consecutively over a 6-week period. RESULTS: Losartan alone significantly reduced the serum uric acid concentration and increased uric acid excretion, whereas the combination of losartan and fenofibrate reduced serum uric acid concentrations further with a concomitant increased uric acid excretion. Fenofibrate alone also reduced plasma uric acid concentration with an increase in urinary excretion, although the effect was weak when compared with the combination treatment. The plasma concentrations and urinary excretion of oxypurines remained unchanged throughout the entire study. CONCLUSION: A combination of fenofibrate and losartan demonstrated an additive urate-lowering effect which may be beneficial in the treatment of patients with gout and hypertriglyceridemia.  相似文献   
1000.
As job stress is now one of the biggest health-related problems in the workplace, several education programs for supervisors have been conducted to reduce job stress. We conducted a supervisor-based randomized controlled trial to evaluate the effects of an education program on their subordinates' psychological distress and job performance. The subjects were 301 employees (46 supervisors and 255 subordinates) in a Japanese sake brewery. First, we randomly allocated supervisors to the education group (24 supervisors) and the waiting-list group (22 supervisors). Then, for the allocated supervisors we introduced a single-session, 60-min education program according to the guidelines for employee mental health promotion along with training that provided consulting skills combined with role-playing exercises. We conducted pre- and post-intervention (after 3 months) surveys for all subordinates to examine psychological distress and job performance. We defined the intervention group as those subordinates whose immediate supervisors received the education, and the control group was defined as those subordinates whose supervisors did not. To evaluate the effects, we employed a repeated measures analysis of variance (ANOVA). Overall, the intervention effects (time x group) were not significant for psychological distress or job performance among both male (p=0.456 and 0.252) and female (p=0.714 and 0.106) subordinates. However, young male subordinates engaged in white-collar occupations showed significant intervention effects for psychological distress (p=0.012) and job performance (p=0.029). In conclusion, our study indicated a possible beneficial effect of supervisor education on the psychological distress and job performance of subordinates. This effect may vary according to specific groups.  相似文献   
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