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101.
Phasically firing neurons in the supraoptic nucleus of the rat hypothalamus: immunocytochemical and electrophysiological studies 总被引:3,自引:0,他引:3
Relations between firing patterns and peptides in supraoptic neurons of rat hypothalamic slice preparations were studied by electrophysiology, intracellular fluorescent dye-marking and immunocytochemistry. Seven out of 10 magnocellular neurons which showed phasically firing patterns were identified by injections of Lucifer Yellow-CH (LY); these were also stained with an anti-vasopressin serum. This report presents direct evidence that most of the phasically firing neurosecretory neurons in the supraoptic nucleus contain vasopressin. This study demonstrates the feasibility of combining immunocytochemical and electrophysiological techniques to study the peptides contents of single mammalian neurons. 相似文献
102.
Masayuki Amagai Yoshio Inokuchi Takeji Nishikawa Yoshiko Shimizu Nobuyoshi Shimizu 《Somatic Cell and Molecular Genetics》1989,15(2):153-158
The tumor promoter 12-O -tetradecanoylphorbol-13-acetate (TPA) induces DNA synthesis in quiescent 3T3-L1 cells but not in its variant VT-1 cells. A gt10 cDNA library was constructed using poly(A)+ RNA from 3T3-L1 cells that were stimulated by TPA for 20 min. Radioactive cDNA probes were prepared from mRNAs of TPA-treated 3 T3-L1 and VT-1 cells and used for screening of the 3T3-L1 cDNA library by differential hybridization. Nine of 6000 phage plaques hybridized only to the 3T3-L1 cDNA probe. Analysis of the nucleotide sequence of five of these clones indicated a high degree of homology with human or mouse type I and type III collagen genes. Three other independent clones showed no homology with any known DNA sequences. These isolated clones of TPA-inducible early (TIE) genes may be useful to study the signal transduction pathway of phorbol esters. 相似文献
103.
104.
Sakashita N Ando Y Obayashi K Terazaki H Yamashita T Takei M Kinjo M Takahashi K 《Virchows Archiv : an international journal of pathology》2000,436(4):345-350
We report an autopsy case of a pedigree of familial amyloidotic polyneuropathy (FAP) with a mutation of isoleucine-50 transthyretin
(ATTR Ser50Ile). A 47-year-old man started developing severe diarrhea and weight loss at age 41 years, followed by urinary
incontinence, autonomic-nervous-system abnormalities and serious heart failure; the diagnosis of FAP (ATTR Ser50Ile) was made
on the basis of genetic, histochemical and immunohistochemical analysis. Six years after the initial symptoms, he died of
septic shock. Autopsy revealed suppurative peritonitis, perforation of the sigmoid colon and marked systemic amyloid deposition.
The total amount of amyloid deposited in the heart was greatly increased and was much lower in the thyroid gland and kidneys
compared with amyloid deposits in ordinary FAP (ATTR Val30Met). Amyloid deposition in peripheral vessel walls was prominent,
particularly in lymphatics and veins. His elder sister, 54 years old, started to develop orthostatic hypotension at age 49
years, followed by dysesthesia, diarrhea and severe congestive heart failure. Endomyocardial biopsy revealed severe TTR–amyloid
deposition; ultrastructural examination demonstrated that amyloid fibrils were deposited disproportionately and extended radially
around microvessels. These characteristic patterns of systemic amyloid deposition and distinct clinical manifestations, especially
in the cardiovascular system, are considered to be a characteristic feature of ATTR Ser50Ile amyloidosis.
Received: 31 August 1999 / Accepted: 19 October 1999 相似文献
105.
Owada T Motomura T Miyashita-Ogawa Y Kawada-Homma M Onishi M Matondo P Terunuma H Numazaki Y Yamashita S Yamamoto N 《Journal of virological methods》2001,94(1-2):15-24
Previously, it was demonstrated that any human immunodeficiency virus type 1 (HIV-1) strain proliferating in peripheral blood mononuclear cells (PBMCs) in vitro, and resuspended in seronegative plasma, could be captured efficiently (mean > 95%) by a porous polypropylene (PP) membrane modified cationically. We investigated if this cationic membrane could capture HIV-1 obtained from seropositive plasma, and confirmed whether this membrane was effective for the preparation of safe plasma products against HIV-1 transmission. Thirty-six seropositive plasma samples derived from HIV-1 positive cohorts in New York and Lusaka (Republic of Zambia), including 18 cases of acquired immunodeficiency syndrome (AIDS) related complex, AIDS and five terminal cases of AIDS, were filtered through the cationic membrane to determine the reduction of RNA concentration, the gag p24 concentration, and infectious titer. Only a small reduction in RNA concentration (mean < 20%) and almost no decrease in gag concentration (mean < 2%) were obtained, despite the fact that the infectivity was eliminated entirely by the filtration. Due to the possibility that anti-HIV-1 antibodies in patients' plasma combine with HIV-1, laboratory-adapted HIV-1(HTLV-IIIB) was mixed with seropositive plasma to test the effect of antibodies on HIV-1 adsorption, and also to investigate the interfacial electrokinetic potential (zeta-potential) of both intact and plasma-treated HIV-1. The zeta-potential of HIV-1(HTLV-IIIB) in the presence of seropositive plasma was neutral as opposed to negative when stored in seronegative plasma or culture medium. Also the rate of HIV-1 capture by the membrane, as determined by the reduction in RNA concentration, sank from 95% to 20%, the same capture percentage observed when filtering plasma of patients. These findings suggested that in patients' plasma, the antibody-masked HIV-1 comprise most of the viral population, and was not trapped on the cationic membrane because of its electrostatic character. Conversely, the cationic membrane was thought to adsorb antibody-free HIV-1 exclusively. It was suggested that each viral swarm had its own zeta-potential, and this difference in electrostatic character determined the extent of the viral adsorption by the cationic membrane. 相似文献
106.
K. Matsuki T. Juji K. Tokunaga M. Mochizuki K. Hayashi Y. Fujino J. Numaga H. Yamashita 《Tissue antigens》1987,29(4):208-213
HLA class I, II, and III antigens were studied in Japanese patients with Beh?et's disease with refractory ocular attacks. In addition to the increased frequency of B51, DQw3, especially TA10-negative DQw3, was increased and DQw1 was decreased significantly in this subgroup of Beh?et's disease. As for complement markers, C4A Q0 was increased. A rare variant of BF S07 was first observed in Japanese. Although the mechanism for the DQw3 association is obscure, a possible hypothesis is that an immune-response or immune-suppression gene linked to the DQ antigens modulates the disease severity and the efficacy of treatments. 相似文献
107.
108.
I Matsuda N Nagata T Matsuura K Oyanagi K Tada K Narisawa T Kitagawa T Sakiyama F Yamashita M Yoshino 《American journal of medical genetics》1991,38(1):85-89
In a retrospective survey done from 1978-1988 in Japan, 32 male patients with ornithine transcarbamylase (OTC) deficiency were identified. We classified a neonatal and 2 late-onset groups, depending on clinical manifestations and the age at onset; group 1 (0-28 days; N = 10), group 2 (29 days-5 years; N = 13), and group 3 (greater than 5 years; N = 9). Compared to findings in the group 2 patients, there was a higher rate of mortality and a higher incidence of mental retardation in association with a great decrease in enzyme activity in group 1. In group 3, the mortality rate and enzyme activities were similar to those in group 1. However, patients in this group were asymptomatic prior to the first episode. Enzyme activities were measured mostly in autopsy samples. The serum citrulline levels (enzyme product) were highest in this group. Thus, the mutant enzymes were apparently labile with greater activities in vivo than in vitro. Treatments, including a protein-restricted diet, arginine supplementation, and sodium benzoate administration, resulted in a favorable prognosis for survivors with partial enzyme deficiency. We wish to emphasize that the incidence of late onset of this disease is higher than heretofore considered. 相似文献
109.
M Kitano G Landini I Semba A Urago K Sugihara H Mukai S Yamashita 《Acta pathologica japonica》1990,40(8):588-595
A mandibular eosinophilic granuloma in a 16-year-old male is reported. This case showed rapid regression, which was clearly demonstrated by histopathological examinations of both preoperative biopsy and surgical materials. Transformation from an eosinophilic granuloma to a xanthomatous granuloma with multinucleated giant cells was observed after only 26 days. Special staining of paraffin sections with peanut agglutinin (PNA) and use of electron microscopy showed that the main component of the lesion in the biopsy material was Langerhans-type histiocytes. These cells had disappeared from the lesion by the time of the operation. At the same time, the number of infiltrating eosinophils was also markedly reduced. It seems appropriate to consider that the rapid regression of this disease was correlated with the rapid reduction in the number of Langerhans-type histiocytes appearing in the granulomatous foci, as well as the number of infiltrating eosinophils. 相似文献
110.
p21(Cip1/WAF1), known as a cell-cycle inhibitory protein, facilitates neurite outgrowth from neurons when present in the cytoplasm. The molecular mechanism of this action is that p21(Cip1/WAF1) forms a complex with Rho-kinase and inhibits its activity. As myelin-derived inhibitors of axonal outgrowth act on neurons by activating Rho, that is responsible for the lack of spontaneous regeneration of the injured central nervous system (CNS), Rho-kinase may be a good molecular target against injuries in the CNS. In this study, we delivered TAT-fusion protein of cytoplasmic p21(Cip1/WAF1) locally after dorsal hemisection of the thoracic spinal cord in rats. The treatment significantly stimulated axonal regeneration and recovery of hindlimb function, and inhibited the cavity formation in the spinal cord after the injury. Cytoplasmic p21(Cip1/WAF1) may provide a potential therapeutic agent that produces functional regeneration following CNS injuries. 相似文献