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51.
Junko Tsudzuki Shiho Ito Takahiko Tsudzuki Tatsuya Wakasugi Masahiro Sugiura 《Current genetics》1994,26(2):153-158
The chloroplast genome of black pine (Pinus thumbergii), a gymnosperm, contains 32 different tRNA genes, 30 of which correspond to those previously identified in tobacco and rice chloroplast genomes. Two additional genes encode tRNAPro (GGG) and tRNAArg (CCG); the former is newly identified while the latter is present in liverwort, Physcomitrella patens and Angiopteris lygodiifolia, chloroplast genomes. Moreover, a partial copy of the split tRNAGly (UCC) gene and full copies of tRNAHis (GUG), tRNAThr (GGU) and tRNASer (GCU) genes are present in the large single-copy region of the genome, suggesting extensive rearrangements of the chloroplast genome during evolutio. No tRNA genes whose tRNA products can recognize codons CUU/C (Leu) and GCU/C (Ala) have been found. We propose that the 32 tRNAs are sufficient to read all the 61 sense codons in the black pine system using the two-out-of-three and the U:N wobble mechanisms. 相似文献
52.
Tumor necrosis factor alpha-induced interleukin-8 production via NF-kappaB and phosphatidylinositol 3-kinase/Akt pathways inhibits cell apoptosis in human hepatocytes 总被引:3,自引:0,他引:3
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Osawa Y Nagaki M Banno Y Brenner DA Asano T Nozawa Y Moriwaki H Nakashima S 《Infection and immunity》2002,70(11):6294-6301
Tumor necrosis factor alpha (TNF-alpha) not only induces apoptotic signals but also causes antiapoptotic and regenerative responses in the liver. However, the molecular mechanism(s) of the latter events remains unclear. In the present study, we examined TNF-alpha-induced genes in Hc human normal (unsensitized) hepatocytes by cDNA microarray analysis. Interleukin-8 (IL-8) induction was the most pronounced of the upregulated genes. The IL-8 protein level was also increased. IL-8 belongs to the ELR-CXC chemokine family and appears to exert mitogenic and antiapoptotic functions in other cell systems. IL-8 expression by TNF-alpha was inhibited when two survival signals, nuclear factor kappaB (NF-kappaB) and phosphatidylinositol 3-kinase (PI3K)/Akt, were inhibited by a mutant form of inhibitor of NF-kappaB (IkappaB); by dominant negative (kinase-dead) Akt; or by treatment with LY 294002, an inhibitor of PI3K. TNF-alpha induced apoptosis in Hc cells that were sensitized by inhibition of NF-kappaB and PI3K activation. IL-8 administration protected mice against concanavalin A-induced hepatitis in vivo. IL-8 also rescued the sensitized Hc cells, at least in part, from TNF-alpha-induced apoptosis in vitro. TNF-alpha inhibited DNA synthesis in unsensitized Hc cells in the absence of serum. Exogenous IL-8 reversed, though anti-IL-8 neutralization antibody enhanced, growth inhibition by TNF-alpha. These results indicate that IL-8, the production of which is stimulated by TNF-alpha, inhibits apoptosis of sensitized hepatocytes and releases normal (unsensitized) hepatocytes from growth inhibition induced by TNF-alpha. 相似文献
53.
Horiuchi T Tsukamoto H Mitoma H Miyagawa H Tamimoto Y Yoshizawa S Harada M Hayashi K Hashimura C Oribe M Okamura S 《International journal of molecular medicine》2004,14(5):813-818
Molecular defects of TNFRSF1A was investigated in members of a family presenting with typical phenotypes of tumor necrosis factor receptor-associated periodic syndrome (TRAPS) and in patients with the autoimmune disorders, systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). Genomic DNA from the members of a family with typical TRAPS, as well as from 100 patients with SLE, 100 patients with RA and 100 healthy individuals, was studied for mutations in exons 2, 3 and 4 of the TNFRSF1A gene. All individuals were Japanese. Three novel missense mutations were identified in the TNFRSF1A. The C70G mutation was identified in family members with typical TRAPS, which was the second case in eastern Asian population. In addition, the T61I and R104Q mutations were each identified in 2 of the 100 SLE patients. The T61I mutation was identified in one of the 100 healthy individuals. No mutations were identified in the 100 RA patients. Functional analysis revealed that PMA-induced shedding of TNFRSF1A from PBMCs was impaired in a patient carrying T61I. A larger scale of study will clarify whether these two mutations, T61I and R104Q, are associated with chronic inflammatory disorders, such as SLE, or not. 相似文献
54.
The biological activity of plurihormonal pituitary adenomas was compared with that of tumors producing only one hormone by evaluating the percentage ofc- myc protein-labeled cells and ultrastructural characteristics. Twenty-five pituitary adenomas producing 3 or more hormones and 14 adenomas producing only I hormone were studied. Tissue sections were stained immunohistochemically using antibodies for pituitary hormones andc- myc protein, and they were examined by electronmicroscopy. DNA extracted from ethanol-fixed, paraffinembedded tissue was analyzed for p53 mutations by polymerase chain reaction and singlestrand conformation polymorphism analysis. The percentage ofc- myc protein-labeled cells in adenomas producing 4 or 5 pituitary hormones was significantly higher (p < 0.01 ) than in those producing 3 or 1 hormones. There were no p53 mutations in plurihormonal adenomas. Pituitary adenomas producing 4 or 5 pituitary hormones demonstrate biological aggressiveness; therefore, multihormone production reflects aggressive capacity rather than degree of differentiation. 相似文献
55.
M Oba K Mizoi S Fujimoto T Yoshimoto J Suzuki 《No shinkei geka. Neurological surgery》1985,13(10):1059-1065
We have previously demonstrated that the preischemic administration of perfluorochemicals (PFC) in combination with 20% mannitol, vitamin E and dexamethasone is effective in protecting the brain from cerebral ischemia. This experimental study was designed to evaluate the effect and limitation of the post-ischemic administration of those 4 agents on cerebral ischemia. We used "Canine model of complete ischemic brain regulated with a perfusion method." Using this model we were able to control the amount of blood flow to the left cerebral hemisphere by using an infusion pump. Infusion blood volume was reduced to 30%, 40% or 50% of the normal state, then the combined treatment was started 1,2,3,4,5 or 6 hours after the onset of ischemia in each ischemic group. By monitoring the EEG for 8 hours of ischemic period, we were able to evaluate the effect of the drugs on cerebral ischemia. In untreated groups, electrical activity deteriorated gradually. In the 30% ischemia group, the EEG became isoelectric within 1 hour following ischemia. In half of the 40% ischemia group, the EEG became isoelectric but in the other half low voltage slow wave were seen to last for 6-8 hours. In the 50% group, the EEG deteriorated gradually but did not disappear within 8 hours. The effectiveness of the treatment was judged by the degree of the recovery of electrical activity. The effectiveness of the treatment appeared to depend on the severity and the duration of ischemia.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
56.
Phenytoin is well known as the anticonvulsant agent and also said to protect the brain against ischemic damage. The purpose of the present experiment is to study the therapeutic effect of phenytoin on cerebral ischemia and confirm whether the effectiveness of phenytoin could be enhanced by combination of free radical scavengers such as mannitol and vitamin E. In this experiment, twenty-five dogs were subjected to ischemia, using the "canine model of complete ischemic brain regulated with a perfusion method" in which it is possible to control the degree of blood flow to a cerebral hemisphere via a perfusion pump at will. Five animals served as untreated control, fifteen received treatment with phenytoin (7 mg/kg in five dogs, 10 mg/kg in five dogs and 30 mg/kg in five dogs) and five treated with 10 mg/kg phenytoin, 2 g/kg of mannitol and 30 mg/kg of vitamin E. These drugs were administered intravenously 20 minutes prior to the production of ischemia, when cerebral blood flow was reduced to one-tenth its normal volume. After one hour, cerebral blood flow was restored and the recovery of electrical activity of the brain and the degree of brain swelling were observed for three hours. With regard to the recovery of EEG, no recovery of EEG was seen subsequent to recirculation except one dog in the control group. Whereas in the group treated with phenytoin, gradual emergence of slow wave ws observed soon after recirculation. The higher the administered dosage is, the better the degree of recovery of EEG was seen. Thus, the dose-related recovery of EEG was observed within the dose ranges tested.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
57.
Yosuke Matsumura Tomoyasu Tsushima Yujiro Ozaki Jun Yoshimoto Takafumi Akagi Tsuneaki Obama Yasutomo Nash Hiroyuki Ohmori 《Cancer chemotherapy and pharmacology》1986,16(2):176-177
Summary We evaluated the effects of 4-epi-Adriamycin (EPI), a derivative of Adriamycin (ADR), in intravesical instillation chemotherapy. The patients received two courses of three daily instillations of 50–80 mg EPI dissolved in 30 ml physiological saline on 3 consecutive days, with an interval of 4 days between courses. Full evaluation was possible in 33 of 35 patients with superficial bladder tumors treated with EPI. Complete response was observed in 4 cases and partial response in 14 cases, giving a response rate of 55%. Side effects such as pollakiuria and pain on micturition occurred in 9 cases. EPI appears to be an effective agent for intravesical instillation chemotherapy in patients with superficial bladder tumors. 相似文献
58.
Yoshitada Yoshioka Hisamitsu Nagase Youki Ose Takahiko Sato 《Ecotoxicology and environmental safety》1986,12(3):206-212
The test method of "activated sludge, respiration inhibition test" proposed by the OECD was critically carried out and compared with other test methods. Investigation of test conditions showed that the moderate deviation from the test conditions defined by the OECD Test Guidelines did not have much effect on the result, and some modifications were proposed to improve the method. This method had a poor detection limit compared with the LC50 test with Oryzias latipes and EC50 of the growth inhibition test with Tetrahymena pyriformis. The susceptivity of the method was particularly poor for the chemicals which were highly toxic in the other two tests. 相似文献
59.
A Takahashi J Suzuki T Sugawara T Yoshimoto 《No shinkei geka. Neurological surgery》1986,14(2):179-187
The ideal treatment of cerebral arteriovenous malformations (AVMs) is thought to be the total resection of nidus. We have been reporting the importance of temporary occlusion of the feeding arteries with the aid of the brain protective substances to prolong the permissible time of occluding these arteries. Because of the difficulty of access to the feeding arteries, some cases are difficult or even impossible to operate. In this communication, four cases of AVM which were successfully resected utilizing intraoperative balloon occlusion of feeders under the administration of the brain protective substances are reported. Case 1. A 14-year-old female was admitted to our clinic because of subarachnoid hemorrhage with ventricular rupture and left cerebellar hemorrhage. Angiography disclosed a large left cerebellopontine angle AVM fed by left anterior inferior cerebellar artery (AICA) and left superior cerebellar arteries (SCAs). Prior to the operation, two balloon catheters were introduced via transfemoral approach; one into the AICA and the other into the basilar artery where left SCAs originated. To prolong the permissible time of occluding these arteries, "Sendai cocktail" (20% mannitol, vitamin E and dexamethazone) and perfluorochemicals were administered. Auditory brain stem response (ABR) was monitored continuously during the operation. The nidus was resected totally with safe using temporary inflation of these balloon catheters. The patient returned to normal life. Case 2. A 35-year-old male was admitted to our clinic complaining of the attack of generalized convulsive seizure.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
60.
A Takahashi T Sugawara K So T Suga T Yoshimoto J Suzuki 《No shinkei geka. Neurological surgery》1986,14(12):1447-1455
We have introduced concept of "chemical" embolization and have tried to develop a new agent which would enable us to embolize the lesion with one-shot injection. Such an agent must be able to occlude diffusely the lesion distal to the catheter. This has made it mandatory to develop a new catheter which can be introduced into the vessel as close to the lesion as possible with fewer risks of clot formation and/or vessel damage. A new superselective balloon catheter for angiography and infusion of liquid embolizing materials has been developed. This catheter consists of a proximal relatively stiff silicone catheter, a short distal thin-walled flexible silicone catheter and silicone balloon. These three silicone components are connected by silicone adhesives. The distal catheter allows us to catheterize fine arteries such as lenticulostriates, while the proximal catheter assures easy manipulation. This balloon catheter can be used for superselective angiography and infusion of liquid embolizing materials. It has been used on nine patients; one with a dural arterio-venous malformation (AVM), four with meningiomas, and four with brain and spinal cord AVMs. In the case of dural AVM and meningiomas, it was possible to easily introduce into the middle meningeal artery distal to the foramen spinosum. In addition, in one of the cases of meningioma, we were able to catheterize one of the main feeding pedicles beyond the pterion. Chemical embolization was carried out in 5 cases with good results. In the case of brain and spinal cord AVM, useful information was obtained from the superselective angiography.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献