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11.
BACKGROUND: Myocardial perfusion single photon emission computed tomography (SPECT) occasionally fails to detect coronary stenosis in patients with coronary artery disease (CAD). We evaluated coronary flow reserve (CFR) using oxygen 15-labeled water in areas with and without ischemia on technetium 99m tetrofosmin stress perfusion SPECT in patients with angiographically documented CAD. METHODS AND RESULTS: Twenty-seven patients with CAD and eleven age-matched normal subjects were studied. Baseline myocardial blood flow (MBF) and MBF during hyperemia induced by intravenous adenosine triphosphate infusion (0.16 mg. kg(-1). min(-1)) were determined with the use of O-15-labeled water positron emission tomography, and the CFR was calculated. Tc-99m tetrofosmin stress/rest SPECT was performed for comparison. On the basis of the results of coronary angiography and SPECT, coronary segments were divided into 3 types: segments with coronary stenosis and a perfusion abnormality on stress SPECT imaging (group A, n = 16), segments with coronary stenosis without a perfusion abnormality (group B, n = 42), and remote segments with no coronary stenosis or perfusion abnormality (group C, n = 18). Baseline MBF values were similar among the 3 groups. CFR in group A was lower (1.82 +/- 0.54) than in group B (2.22 +/- 0.87, P <.05), in group C (2.92 +/- 1.21, P <.01), and in normal segments (3.86 +/- 1.24, P <.001). CFR in group B was lower than in group C (P <.02) and in normal segments (P <.001). CFR in group C was lower than in normal segments (P <.02). CONCLUSIONS: Areas with a perfusion abnormality on stress SPECT had reduced CFR. In the areas without a perfusion abnormality and with coronary stenosis, lowering of CFR was intermediate between the areas with a perfusion abnormality and remote segments. Moreover, CFR was slightly, but significantly, lower in remote segments in patients with CAD compared with normal segments.  相似文献   
12.
Various tannins and related compounds were compared for their ability to stimulate the iodination (incorporation of radioactive iodine into an acid-insoluble fraction) of human peripheral blood monocytes. The stimulating activity of most of the monomeric and dimeric hydrolyzable tannins was generally higher than that of the trimeric and tetrameric compounds. Compounds that had dehydrohexahydroxydiphenoyl or chebuloyl groups had considerably less activity than those that had other functional groups (hexahydroxydiphenoyl, valoneoyl, dehydrodigalloyl, isodehydrodigalloyl, lactonized valoneoyl, hellinoyl, euphorbinoyl, dehydroeuphorbinoyl or woodfordinoyl group). The methylated derivative, nonacosa-O-methylcoriariin A, was essentially inactive, suggesting the requirement of a phenolic hydroxyl group. Three condensed tannins ((-)-epicatechin 3-O-gallate (ECG)-dimer, ECG-trimer and ECG-tetramer) significantly stimulated both monocyte iodination and their interleukin-1-like factor production. The results suggest the dependence of stimulation of monocyte iodination by tannins and related polyphenols on molecular weight.  相似文献   
13.
Effects of 3-[[[2-(3,4-dimethoxyphenyl)ethyl]carbamoyl] methyl]-amino-N-methylbenzamide (DQ-2511), a newly synthesized compound, were evaluated using various types of experimental gastric and duodenal ulcers in rats. Pretreatment with DQ-2511, over the dose range 30-300 mg/kg p.o., resulted in a dose-related inhibition of water-immersion stress-, serotonin-, acetylsalicylic acid (ASA)-, indometacin-, ethanol-, and 2-deoxy-D-glucose(2DG) plus indometacin-induced gastric ulcers as well as cysteamine-induced duodenal ulcers. The antiulcer potencies of DQ-2511 were equal to or greater than those of H2-receptor antagonist cimetidine in these ulcer models except for ASA- and 2DG plus indometacin-induced ulcers. The rate of healing of chronic gastric ulcers induced by acetic acid was significantly accelerated by DQ-2511 (100 and 300 mg/kg p.o.) but not by the same doses of cimetidine. DQ-2511, at doses of 30 mg/kg p.o. and above, produced a significant decrease in gastric acid and pepsin output in pylorus-ligated rats. In anesthetized rats with acute gastric fistulae, 30 mg/kg i.v. of DQ-2511 significantly inhibited gastric acid secretion stimulated by 2DG, whereas it did not affect gastric hyperacidity evoked by either carbachol, histamine or pentagastrin. At effective antiulcer doses, this compound produced a sustained increase in gastric mucosal blood flow in conscious, restrained rats. Based on these observations, DQ-2511 is characterized as a new antiulcer compound with beneficial effects on both gastric aggressive and defensive factors. Furthermore, these results indicate a possible superiority of DQ2511 over cimetidine in regard to its antiulcer potency and spectrum.  相似文献   
14.
Absorption of tetrahydropyranyl adriamycin (THP) administered immediately after transurethral resection of bladder carcinoma (TUR-Bt) has not been reported. In this study, we have examined the absorption of THP and the systemic toxicity in the early post-TUR period. Of 21 patients with bladder carcinoma, 10 had a solitary tumor and 11 multiple tumors. Twenty mg THP in 40 ml of sterile water was intravesically administered on days 1, 3, 5, 7, 14 and 28, and then every 4th week. The THP solution was retained for 2 hours. The blood THP concentration was measured 30 minutes and 2 hours after the intravesical administration on days 1, 7 and 28. No systemic side effects were observed. Thirteen of the 38 (34%) samples contained a detectable level (more than 1 ng/ml) of THP on the post-TUR-Bt on day 1, 8, of 42 (19%) on day 7, and 3 of 18 (17%) on day 28. Altogether, 24 of the 98 (24%) samples contained more than 1 ng/ml THP. The highest blood THP level was 23 ng/ml on day 1. The differences between frequency of detection of blood THP in the samples at 30 minutes and 2 hours were not statistically significant. The difference between average concentration of blood THP of patients with solitary and multiple tumors also was not significant. These results indicate that intravesical THP administration starting within 24 hours after TUR-Bt can not result in significant systemic absorption of THP, and the systemic toxicity can be avoided.  相似文献   
15.
Beta-adrenoceptors in femoral and mesenteric arteries from 13-week-old spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto (WKY) rats were studied using radioligand binding assays and were compared with in vitro measurements of beta-adrenoceptor-mediated relaxation. The relaxant responses to noradrenaline via beta-adrenoceptors were significantly decreased in the SHR femoral artery when compared with the WKY femoral artery. However, under the same conditions, arterial relaxant responses to forskolin, an activator of adenylate cyclase, were not significantly different between SHR and WKY rats. Specific binding of 125I-iodocyanopindolol to membranes prepared from femoral arteries of SHR and WKY rats was saturable and of high affinity. Neither the equilibrium dissociation constant of 125I-iodocyanopindolol, nor the maximum number of binding sites were significantly different between SHR and WKY rats. Similar results were obtained in the case of mesenteric arteries from SHR and WKY rats. These results indicate that the decreased responsiveness to beta-adrenoceptor stimulation in SHR arteries is not associated with alterations in beta-adrenoceptors and further support the hypothesis that a reduced function of the stimulatory guanosine triphosphate-binding protein is responsible for the decreased responsiveness to a variety of receptor agonists whose mechanism of action involves adenylate cyclase activation.  相似文献   
16.
KM2210, a conjugate of estradiol and chlorambucil (CBL), which was originally developed as an anti-breast cancer agent, inhibits proliferative response of human mononuclear cells to alloantigens in mixed lymphocyte culture in a dose-dependent manner, but has no effect on their response to phytohemagglutinin. Neither estradiol benzoate nor CBL alone showed these unique actions. The suppressive effect of KM2210 on MLC was abrogated by adding of anti-transforming growth factor-beta (TGF-beta) antibody to the culture, but was not affected by the addition of interleukin-2, suggesting that KM2210, unlike CBL, displays its actions via TGF-beta. In experimental allogeneic bone marrow transplantation using mice, daily oral administration of KM2210 (2 mg/kg/day) for 30 days posttransplant significantly inhibited the alloantigen-specific immune reactions. Furthermore, the survival rate of the KM2210-treated mice was significantly higher than that of the cyclosporine-treated (2 mg/kg/day, p.o.) mice, and no adverse effect of KM2210 on hematopoietic recovery was found. These results strongly suggest possible clinical benefits of KM2210 as a new immunosuppressive agent for the prevention and treatment of graft-versus-host disease and other allospecific immune reactions.  相似文献   
17.
To apply Nd:YAG laser irradiation through a new sapphire tip contact laser method to catheter ablation in treatment of tachy-arrhythmias, effects of laser irradiation on ventricular myocardium were investigated in 10 mongrel dogs. Nd:YAG lase (1064nm) discharges were delivered to different sites on the endomyocardium at power of 5, 10, 15, 20 or 25w with duration of 3, 5, or 10 seconds (sec.) respectively in closed beating hearts. Histopathologically, the lesion irradiated was clearly demarcated from the normal myocardium by the construction band necrosis zone. The depth of injured myocardium was less than 2mm with 3 sec. irradiations, with 5 sec. from 1 mm to 4 mm in proportion to power increase, with 10 sec. from 3mm to 8 mm in proportion to the power from 5w to 15w and could not be measured in cases of more than 20w irradiations. Although with every irradiation duration, the depth of injury increased in proportion to the power increase. With the same total energy, a longer time of irradiation produced deeper injury than a shorter time. This method makes it easier to keep the laser positioned to target than bare laser, and is suitable for use in catheter ablation.  相似文献   
18.
FK506 is a potent immunosuppressive agent on experimental and clinical organ transplantation. We studied the the effect of this agent on segmental pancreas allograft in mongrel dogs. Graft survival was prolonged significantly with continuous administration of FK506, 0.3mg/kg/day intramuscular and 1.0mg/kg/day orally. However such symptoms as loss of appetite, nausea and extreme emaciation were observed and caused death. While bolus therapy of FK506 (3 days administration with the dose of 1.0mg/kg i.m. from 4 to 6 day postoperatively) showed the same immunosuppressive effect as continuous therapy and less side effect. Furthermore it was suggested that FK506 plasma levels were concerned with the appearance of side effect. In conclusion, the administration of FK506 with plasma level monitoring was thought to be useful on pancreas transplantation.  相似文献   
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