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991.
It is known that β-adrenoceptor antagonists are effective in the treatment of akathisia, one of the extrapyramidal side effects
that occur during neuroleptic treatment. Neuroleptic-induced catalepsy, a model of neuroleptic-induced extrapyramidal side
effects, was considered suitable as a model for predicting neuroleptic-induced akathisia in humans, although neuroleptic-induced
catalepsy was not considered a specific test for neuroleptic-induced akathisia. Therefore, the effects of carteolol, a β-adrenoceptor
antagonist, on haloperidol-induced catalepsy in rats were behaviorally studied and compared with those of propranolol and
biperiden, a muscarinic receptor antagonist. Carteolol, as well as propranolol and biperiden, inhibited the haloperidol-induced
catalepsy. The inhibitory effect of carteolol was almost comparable to that of propranolol, but was weaker than that of biperiden.
Carteolol did not evoke postsynaptic dopamine receptor-stimulating behavioral signs such as stereotypy and hyperlocomotion
in rats. Carteolol did not antagonize the inhibitory effects of haloperidol on apomorphine-induced stereotypy and locomotor
activity in rats. In addition, carteolol did not evoke 5-HT1A receptor-stimulating behavioral signs such as flat body posture and forepaw treading and did not inhibit 5-hydroxytryptophan-induced
head twitch in rats. Finally, carteolol did not inhibit physostigmine-induced lethality in rats. These results strongly suggest
that carteolol improves haloperidol-induced catalepsy via its β-adrenoceptor antagonistic activity and is expected to be effective
in the treatment of akathisia without attenuating neuroleptic-induced antipsychotic effects due to its postsynaptic dopamine
receptor antagonistic activity.
Received: 7 March 1996/ Final version: 27 November 1996 相似文献
992.
Tolerance to acute compression injury and recovery of nerve function in chronically compressed spinal nerve roots: Experimental study 总被引:1,自引:0,他引:1
Koji Otani Satoru Kayama Guang-Ping Mao Shinichi Konno Katsuhiko Sato Kjell Olmarker Shinichi Kikuchi 《Journal of orthopaedic science》1997,2(4):266-270
Chronic compression (10 mm Hg for 1 week) of spinal nerve roots in a dog experimental model has been shown to reduce nerve
conduction velocity. Although injured, the compressed nerve roots demonstrated increased resistance to acute compression applied
in addition to the chronic compression after 1 week. In the present study reduction of nerve conduction velocity induced by
chronic compression recovered when the duration of compression was extended to 1 month. However, the tolerance to additionally
applied compression was still present. This study provides important base-line data for continued studies of the basic mechanisms
of the development of tolerance to changes in compression pressure levels in chronically compressed nerve roots. 相似文献
993.
Y Yoshinaga S Fujita M Gotoh T Nakamura M Kikuchi S Hirohashi 《Japanese journal of cancer research》1992,83(12):1257-1261
Hepatocyte growth factor (HGF)/scatter factor (SF) is a cytokine which is produced by mesenchymal cells and stimulates the motility of some epithelial cells, including cancer cells and vascular endothelial cells. Two human lung cancer cell lines, PC-1 and PC-13, were found to produce a protein which was indistinguishable from HGF/SF with regard to biological activities and immunological characteristics, although they were derived from epithelial cells. In general, highly aggressive cancer cells often show some mesenchymal characteristics, and production of HGF/SF by cancer cells is also considered as a phenomenon of acquisition of mesenchymal phenotype, which may be involved in cancer invasion and progression. These cell lines showed no apparent response to exogenous HGF/SF. In addition, no c-met proto-oncogene product was detectable in these cells by Western blot analysis. Although the function of HGF/SF produced by cancer cells, either autocrine or paracrine stimulation, remains to be studied, this is the first report to describe cancer cells producing HGF/SF. 相似文献
994.
Molecular cloning of the human cDNA for a stimulatory GDP/GTP exchange protein for c-Ki-ras p21 and smg p21. 总被引:4,自引:0,他引:4
A Kikuchi K Kaibuchi Y Hori H Nonaka T Sakoda M Kawamura T Mizuno Y Takai 《Oncogene》1992,7(2):289-293
We have previously purified smg GDP dissociation stimulator (GDS) from bovine brain and isolated its cDNA from a bovine brain cDNA library. smg GDS stimulates the GDP/GTP exchange reaction of a group of small GTP-binding proteins (G proteins), including at least c-Ki-ras p21, smg p21A, smg p21B, rhoA p21 and rhoB p21, by stimulating the dissociation of GDP from and the subsequent binding of GTP to each small G protein. In this study, we have isolated and sequenced the cDNA of smg GDS from a human brain cDNA library using the cloned bovine smg GDS cDNA. The cDNA has an open reading frame encoding a protein of 558 amino acids with a calculated Mr value of 61,122. Human smg GDS shares 93% nucleotide and 96% amino acid sequence homologies with bovine smg GDS. The isolated cDNA is expressed in Escherichia coli, and the encoded protein shows the physical and functional properties similar to those of bovine smg GDS. 相似文献
995.
Yasuteru Yoshinaga Shin Fujita Masahiro Gotoh Toshikazu Nakamura Masahiro Kikuchi Setsuo Hirohashi 《Cancer science》1992,83(12):1257-1261
Hepatocyte growth factor (HGF)/scatter factor (SF) is a cytokine which is produced by mesenchymal cells and stimulates the motility of some epithelial cells, including cancer cells and vascular endothelial cells. Two human lung cancer cell lines, PC-1 and PC-13, were found to produce a protein which was indistinguishable from HGF/SF with regard to biological activities and immunological characteristics, although they were derived from epithelial cells. In general, highly aggressive cancer cells often show some mesenchymal characteristics, and production of HGF/SF by cancer cells is also considered as a phenomenon of acquisition of mesenchymal phenotype, which may be involved in cancer invasion and progression. These cell lines showed no apparent response to exogenous HGF/SF. In addition, no c-met proto-oncogene product was detectable in these cells by Western blot analysis. Although the function of HGF/SF produced by cancer cells, either autocrine or paracrine stimulation, remains to be studied, this is the first report to describe cancer cells producing HGF/SF. 相似文献
996.
997.
998.
S Miyamoto H Kikuchi I Nagata Y Akiyama K Itoh O Yamagiwa S Asahi 《Journal of neurosurgery》1992,77(5):812-815
The authors present a modified surgical procedure for extracranial vertebral artery reconstruction. The use of the proposed technique results in access to the V3 segment of the vertebral artery between the C-1 and C-2 vertebrae through the retrojugular space without requiring bone rongeuring. A saphenous vein bypass graft was placed between the common carotid artery and the V3 segment of the vertebral artery in three patients with bilateral occlusive lesions of the proximal vertebral arteries. 相似文献
999.
T Kunimura T Morohoshi M Sato H Kikuchi M Kanda S Taguchi Y Hatta K Miura 《Gan to kagaku ryoho. Cancer & chemotherapy》1992,19(3):355-360
Histological analyses of 16 autopsies of pancreatic carcinoma [9 cases after intra-arterial infusion chemotherapy (IAC), and 7 cases of systemic chemotherapy (SC)] were performed. Histological effects of chemotherapy (Shimosato) were seen in 15 cases, but less than 5 Grade II a. cases of IAC and 4 cases of SC showed Grade IIa, 3 cases of IAC and 3 cases of SC showed Grade I. The ratio of Grade IIa was almost the same in IAC and SC. But histologically, anaplastic change, sarcomatous change and Bizarre cells, immunohistologically positive to anti-EMA and Vimentin antibody, were dominant in IAC. And clinically, serum tumor markers (CEA, CA19-9) were fewer in almost all the cases in IAC. These results may suggest that the anti-tumor effect of IAC was greater than the histological appearance. 相似文献
1000.
K Kikuchi T Kakizaki M Sawafuji N Hangai T Yamamoto T Kobayashi M Watanabe M Kawamura R Kato K Kobayashi 《Kyobu geka. The Japanese journal of thoracic surgery》1992,45(1):14-18
Thirty-seven patients with tracheobronchial lesions by malignant tumor were treated with Nd-YAG laser. Thirty-seven patients were twenty-three males and fourteen females and ages ranged from 34 to 79 years. Diseases included were primary tracheal tumor in 3 cases, lung cancer in 16 (8 squamous cell carcinoma, 5 adenocarcinoma, 2 large cell carcinoma, 1 small cell carcinoma), cancer of adjacent organs in 9 (5 thyroid cancers, 4 esophageal cancers), and metastatic cancer to the lung or mediastinal lymph nodes in 9 (4 renal cell carcinoma, 2 thyroid cancer, one patient respectively, colon cancer and breast cancer). Intermittent irradiation of YAG laser was done for 0.5 second at 30-40 Watt through flexible bronchoscope under local anesthesia. It was repeated 1 to 41 times (mean 4.1 times) and energy amount was 148 Joules to 18,513 Joules (mean 3,305 J). The result was; stenosis disappeared in 22 cases (59.4%), improved in 14 (37.8%), and in one case YAG laser therapy discontinued due to intractable bleeding. The Nd-YAG laser therapy for tracheobronchial lesions by malignant tumor is very useful to improve dyspnea or atelectasis. 相似文献