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131.
Indocyanine green iris angiography of lung carcinoma metastatic to the iris   总被引:1,自引:0,他引:1  
· Background: To investigate the usefulness of indocyanine green (ICG) iris angiography for monitoring vascular abnormalities and the clinical course of metastatic iris tumor during chemotherapy. · Methods: We performed ICG iris angiography at several points during systemic chemotherapy for a 67-year-old man who had been diagnosed as having small-cell carcinoma of the lung with metastatic iris tumors. · Results: ICG iris angiography clearly demonstrated hyperfluorescent tumor vessels, rubeosis iridis, and dilated iris stromal vessels. After chemotherapy, these hyperfluorescent vessels and rubeosis regressed. · Conclusion: ICG iris angiography appears to be an effective and useful method for observing abnormal vessels associated with metastatic iris tumors. Received: 11 May 1998 Revised version received: 30 July 1998 Accepted: 13 August 1998  相似文献   
132.
The reductive debromination of the hypnotic (alpha-bromoiso-valeryl)urea to (3-methylbutyryl)urea by intestinal bacteria has been studied. The caecal contents of rats, mice, hamsters, guinea-pigs and rabbits had significant debrominating activity toward (alpha-bromoiso-valeryl)urea. The cell-free extract of intestinal bacteria from the caecal contents of rats had debrominating activity in the presence of both flavin mononucleotide (FMN) and NADH (or NADPH) under anaerobic conditions. Seven pure strains of intestinal bacteria were also tested and the highest activity was observed with Clostridium sporogenes. The cell-free extract of Clostridium sporogenes had debrominating activity in the presence of both FMN and NADH (or NADPH), and this activity was inhibited by sodium arsenite and potassium cyanide. The activity of the cell-free extract was also supported by the photochemically reduced form of FMN. The debromination in intestinal bacteria seems to proceed in two steps--reduction of flavins by bacterial flavin reductase(s) in the presence of NADPH or NADH, and then the reductive debromination of (alpha-bromoiso-valeryl)urea to (3-methylbutyryl)urea by bacterial dehalogenase(s) using the reduced flavins as an electron donor. These results indicate that intestinal bacteria play a role in the reductive debromination of (alpha-bromoiso-valeryl)urea to (3-methylbutyryl)urea in animals. The debromination is inhibited by oxygen and dependent on flavins.  相似文献   
133.
Neutrophil functions, including chemotaxis, reactive oxygen species (ROS)-producing capacity of neutrophils, and serum opsonic activity were investigated in 9 young healthy male volunteers. Venous blood of these volunteers was obtained under standardized conditions at 4-h intervals over a 24-h span. Neutrophil chemotaxis was evaluated by a modified Boyden technique, ROS-producing capacity of neutrophils and serum opsonic activity were measured by a simultaneous multiple measurement system based on luminol-dependent chemiluminescence and indicated by peak height and peak time. ROS-producing capacity of neutrophils and serum opsonic activity were activated in the daytime, and decreased from night to morning. There were negative correlations between the peak time of the luminol-dependent chemiluminescent response, neutrophil number (p<0.01) and segmented neutrophil number (p>0.01). On the other hand, no significant correlations were noted between serum opsonic activity and IgG, IgA, IgM, C3 or C4. In contrast, the peaks of neutrophil chemotaxis were at the wake-up time (6:00a.m.) and in the evening (6:00p.m.). This study indicates that diurnal variation of neutrophil function exists.  相似文献   
134.
We examined the efficacy of two new preservation solutions containing trehalose-an extracellular type (ET-K) of solution and an intracellular type (IT-K) of solution — in relation to that of Euro-Collins (EC) solution in 20-h canine lung preservation. Canine lungs were flushed with one of the three solutions (n=5 for each solution) after pretreatment with PGE1 (20 g/kg) and were stored for 20 h at 4°C. The left lungs were transplanted and evaluated to 6 h post transplant. In the ET-K group, the arterial oxygen tension after reperfusion was significantly higher than in the IT-K and EC groups. The pulmonary vascular resistance, wet/dry weight ratio, and histological evaluation of each transplanted lung in the ET-K group were also better than in the IT-K and EC groups. This indicates that ET-K solution is useful for 20-h preservation of canine lung grafts.  相似文献   
135.
Summary DPI 201-106 (DPI), a novel and potent cardiotonic agent, exhibits its effects by prolonging the open state of Na+ channels, resulting in an increase in action potential duration, and thus, is supposed to share the class III antiarrhythmic activity. The effects of DPI on the hemodynamics, intraventricular conduction and refractoriness of heart, and the incidence of arrhythmias induced by programmed electrical ventricular stimulation (PES) were compared with (±)-dobutamine. Dogs which survived for 5 to 7 days after the induction of myocardial infarction were used as the model. The presence of sub-acute myocardial infarction caused by occluding the left anterior descending coronary artery elicited a mild left ventricular dysfunction represented by a significant decrease in peak LV dp/dt by about 20%.Both i.v. bolus injection of DPI (1, 3 and 5 mg/kg) and i. v. continuous infusion of dobutamine (3, 5 and 10 g/kg/min), which were administered in a cumulative manner, dose-dependently improved the hemodynamic parameters. At the higher doses of both DPI (3 and 5 mg/kg) and dobutamine (5 and 10 g/kg/min) the control values were reached or even exceeded. DPI dose-dependently increased the effective refractory period (ERP) of both non-infarcted and infarcted ventricular myocardia to a similar degree, but the conduction time showed a frequency-dependent increase in the infarcted myocardium to a greater degree than in the non-infarcted myocardium after DPI. In contrast, dobutamine decreased the ERP in both non-infarcted and infarcted myocardia, and slightly increased the difference of refractoriness between the non-infarcted and infarcted zones with no effect on the intraventricular conduction. In the PES study, DPI (3 and 5 mg/kg) produced a significant decrease in the incidence of ventricular tachycardia, whereas dobutamine (5 and 10 g/kg/min) tended to worsen the arrhythmias. These findings suggest that cardiotonic agents with a class III antiarrhythmic property such as DPI may be potentially useful for the management of heart failure accompanied by ischemic heart disease.Abbreviations DPI, DPI 201-106; PES programmed electrical ventricular stimulation - LV dp/dt the rate of rise of left ventricular pressure - ERP effective refractory period - RVOT right ventricular outflow tract - VT ventricular tachycardia - LAD left anterior discending coronary artery Send offprint requests to T. Uematsu at the above address  相似文献   
136.
Experiments were made to observe the effects of the maternal administration of cadmium and zinc and their influence on the metal-binding capacity of metallothionein in the rat fetus. Metallothionein was detected in the fetal liver as early as day 16 of gestation and may have appeared earlier. The zinc concentration in the metallothionein fraction was low on day 16 but increased as gestation progressed. The metal-binding capacity was fairly high on day 16 but increased at a slower rate than the zinc concentration. Following the intraperitoneal administration of zinc (100 moles Zn/kg) or cadmium (5 moles Cd/kg) once a day on days 14, 15 and 16 of gestation to the dam, the concentration of zinc in the metallothionein fraction of the maternal liver was far greater than that in the fetal liver. In contrast, cadmium was found only in the metallothionein fraction of the maternal liver; it was not found in the fetal liver, which suggests an effective placental barrier to cadmium. The metalbinding capacity in the fetal liver was induced by the maternal administration of zinc, but not cadmium.  相似文献   
137.
In order to obtain basic data on the effect of broad-spectrum protease inhibitor against local symptoms of Viperidae snake envenomation, inhibitory capacity of rat murinoglobulin on local hemorrhagic and edematogenic activities of venoms from Crotalus atrox, Bothrops jararaca, Lachesis muta muta, Trimeresurus flavoviridis and Echis carinatus sochureki were examined. Murinoglobulin, pre-incubated with the crude venoms at 37 degrees C for 15 min, inhibited hemorrhagic activity of all five venoms to various extents. The activity of C. atrox was almost completely inhibited at the murinoglobulin/venom ratio (w/w) of 20. The activity of B. jararaca, Lachesis muta muta and T. flavoviridis venoms was considerably inhibited at the ratio of 20 (77.2, 80.0 and 86.2% inhibition, respectively), however some of the activity still remained even at the ratio of 40 (84.2, 79.8 and 86.2% inhibition, respectively). Among the five venoms, E. c. sochureki venom is quite resistant to murinoglobulin treatment and statistically significant inhibition was only found at the ratio of 40 (64.1% inhibition). Fibrinolytic and gelatinase activities were more susceptible to murinoglobulin inhibition. The treatment at the ratios of 10 and 20 almost completely inhibited respectively the fibrinolytic and the gelatinase activities of all the venoms. Murinoglobulin treatment also significantly inhibited the edematogenic activity of L. muta muta, T. flavoviridis and Echis carinatus sochureki. The treatment of murinoglobulin at the ratio of 40 considerably suppressed the swelling up to 60 min after subcutaneous injection of L. muta muta and E. c. sochureki venoms, and up to 30 min after T. flavoviridis venom injection. Murinoglobulin is a potent inhibitor against local effects of multiple snake venoms in Viperidae family.  相似文献   
138.
Inducible nitric oxide (NO) synthase (iNOS) is believed to contribute to the pathogenesis of endotoxin-induced uveitis (EIU). In the present study, we investigated the inhibitory effects of N(G)-nitro-L-arginine methyl ester (L-NAME), a non-selective NOS inhibitor, and S,S'-1,4-phenylene-bis(1,2-ethanediyl)bis-isothiourea (PBITU), a potent and selective iNOS inhibitor, on intraocular NO production in EIU rabbits using an in vivo intraocular microdialysis technique. The flare level in the anterior chamber increased from 1h after the injection of 100 micro g/kg lipopolysaccharide (LPS), and continued to increase for 24h. Aqueous humor protein concentrations were significantly increased at 24h after LPS-injection. These changes were significantly reduced by L-NAME (10mg/kg) and PBITU (1mg/kg), but not by D-NAME (10mg/kg). The increase in NO(2)(-) and NO(3)(-) levels in the dialysate induced by LPS was significantly inhibited by L-NAME (10mg/kg) and PBITU (1mg/kg), but not by D-NAME (10mg/kg). These results suggest that activation of iNOS may play a key role in the development of EIU, and selective inhibitors of iNOS may have therapeutic applications in the treatment of EIU.  相似文献   
139.
140.
PURPOSE: Valosin-containing protein (VCP; also known as p97) was shown to be associated with antiapoptotic function and metastasis via activation of nuclear factor kappa-B signaling pathway. In this study, association of VCP expression with recurrence of gastric carcinoma (GC), in which lymphatic vessels are the main route of spread, was examined. PATIENTS AND METHODS: VCP expression in 330 patients with GC (242 males and 88 females) with ages ranging from 26 to 81 years (median, 60 years) was analyzed by immunohistochemistry, in which staining intensity in tumor cells was categorized as weaker (level 1) or equal to or stronger (level 2) than that in endothelial cells. RESULTS: Ninety-four (28.7%) patient cases showed level 1 and 233 patient cases (71.3%) showed level 2 VCP expression. Patients with level 2 expression showed higher rates of large tumor size (P <.0001), undifferentiated histologic subtype (P <.05), presence of vascular and lymphatic invasion (P <.0001 for both), presence of lymph node metastasis (P <.0001), deep tumor invasion (P <.0001), and poorer disease-free and overall survivals (P <.0001 for both) compared with those with level 1 VCP expression. Multivariate analysis revealed VCP expression level as an independent prognosticator for disease-free and overall survival. VCP level was an indicator for disease-free and overall survival in the early (pT1; P <.01 and P <.05, respectively) and advanced (pT2-4; P <.05 for both) group of pathologic tumor-node-metastasis system classification. CONCLUSION: The prognostic significance of VCP expression level in GC was demonstrated.  相似文献   
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