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71.
Production of antiserum against antitumor protein-bound polysaccharide preparation, PSK (Krestin) and its pharmacological application 总被引:1,自引:0,他引:1
H Endoh K Matsunaga C Yoshikumi Y Kawai T Suzuki K Nomoto 《International journal of immunopharmacology》1988,10(2):103-109
Antiserum against a protein-bound polysaccharide preparation (PSK) was produced by immunizing New Zealand White rabbits with PSK. The intestinal absorption of PSK in mice was visualized by indirect immunofluorescent staining with anti-PSK serum. The change in blood levels of 14C after oral administration of 14C-PSK and the recovery of 14C by antiserum were determined. The results indicated that antigenic epitopes in PSK are not completely destroyed during the process of digestion, absorption and distribution, but the changes of serum levels of 14C radioactivity differ from those of immunoreactive radioactivity. These results suggest that multiple processes are involved in the fate of PSK administered orally. 相似文献
72.
Histamine content, synthesis and degradation in nasal mucosa and lung of guinea-pigs treated with toluene diisocyanate (TDI) 总被引:1,自引:0,他引:1
Y. Abe S. Ogino M. Irifune I. Imamura Y. Q. Liu H. Fukui T. Matsunaga 《Clinical and experimental allergy》1993,23(6):512-517
We have reported the presence of a histamine synthesizing enzyme, histidine decarboxylase (HDC), and histamine degrading enzymes, histamine N-methyltransferase (HMT) and histaminase (diamine oxidase, DAO) in human nasal mucosa and the histamine content of the mucosa. In this study, we demonstrate the influences of the toluene diisocyanate (TDI) treatment on the histamine content and these enzyme activities in guinea-pigs as an animal model of respiratory hypersensitivity. Application of TDI to the nasal vestibuli induced intense nasal allergy-like and mild asthma-like responses in TDI-sensitized guinea pigs. Increases in the histamine content and HDC and HMT activities were observed in the nasal mueosa and lung of TDI-sensitized guinea pigs. No apparent changes in the histaminase activities were observed in either the nasal mucosa or the lung. These data suggest that the turnover rate of histamine is increased in the nasal mucosa and the lung of guinea pigs with respiratory hypersensitivity. 相似文献
73.
Navia JL Zahr F Fukamachi K Goodin M Ragaller P Chen JF Kopcak MW Dessoffy R Ootaki Y Kamohara K Akiyama M Gutierrez A Navia JA Atik F Cosgrove DM 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2005,51(6):686-691
Myocardial salvage through coronary sinus intervention has been documented. The AutoRetroPerfusion Cannula is a novel device that is able to perfuse the coronary bed retrogradely through the coronary sinus with arterial blood generated from a peripheral artery with no need for a pump. The cannula consists of a distal end that, once secured in the coronary sinus, opens an umbrella-like membrane to create pressure in the coronary sinus, and at the same time has small channels directed backwards to the right atrium to provide pressure relief. The cannula is introduced from the axillary vein under local anesthesia and the proximal end, which consists of a graft, is anastomosed to the axillary artery to start autoperfusion once the distal end is secured in the coronary sinus and the occluding membrane is open. The AutoRetroPerfusion Cannula was tested in the in vitro mock loop under 50-120 mm Hg of proximal pressure and 50, 100, and 150 ml/min of total flow in the cannula. We were able to achieve the nominal design point of 40-80 mm Hg of distal pressure and 50-150 ml/min of distal flow by adjusting the number, diameter, and length of the small backwards channels. 相似文献
74.
Hiroki Ueda Liu Hong Masaya Yamamoto Keiji Shigeno Masatoshi Inoue Toshinari Toba Makoto Yoshitani Tatsuo Nakamura Yasuhiko Tabata Yasuhiko Shimizu 《Biomaterials》2002,23(4):1003-1010
The objective of this study was to evaluate the potential of collagen sponge incorporating transforming growth factor-beta1 (TGF-beta1) to enhance bone repair. The collagen sponge was prepared by freeze-drying aqueous foamed collagen solution. Thermal cross-linking was performed in a vacuum at 140 degrees C for periods ranging from 1 to 48 h to prepare a number of fine collagen sponges. When collagen sponges incorporating 125I-labeled TGF-beta1 were placed in phosphate-buffered saline (PBS) solution at 37 degrees C, a small amount of TGF-beta1 was released for the first hour, but no further release was observed thereafter, irrespective of the amount of cross-linking time the sponges had received. Collagen sponges incorporating 125I-labeled TGF-beta1 or simply labeled with 125I were implanted into the skin on the backs of mice. The radioactivity of the 125I-labeled TGF-beta1 in the collagen sponges decreased with time; the amount of TGF-beta1 remaining dependent on the cross-linking time. The in vivo retention of TGF-beta1 was longer in those sponges that had been subjected to longer cross-linking times. The in vivo release profile of the TGF-beta1 was matched with the degradation profile of the sponges. Scanning electron microscopic observation revealed no difference in structure among sponges subjected to different cross-linking times. The TGF-beta1 immobilized in the sponges was probably released in vivo as a result of sponge biodegradation because TGF-beta1 release did not occur in in vitro conditions in which sponges did not degrade. We applied collagen sponges incorporating 0.1 microg of TGF-beta1 to skull defects in rabbits in stress-unloaded bone situations. Six weeks later, the skull defects were covered by newly formed bone, in marked contrast to the results obtained with a TGF-beta1 free empty collagen sponge and 0.1 microg of free TGF-beta1. We concluded that the collagen sponges were able to release biologically active TGF-beta1 and were a promising material for bone repair. 相似文献
75.
Kobori Kiyohisa Suzuki Keiji Yoshida Yoji Ooneda Genju 《Virchows Archiv : an international journal of pathology》1979,385(1):29-39
Summary Experimental contraction was produced in the rat mesenteric arteries and the arterial segments were studied morphologically. When the rat mesenteric artery was exposed in physiological saline solution at 37° C and 2–3 mg of methoxamine hydrochloride (10 mg/ml) was dripped onto it, intense contraction was observed for about 30 min but elevation in blood pressure was slight. During the contraction, numerous vacuoles were seen in the medial smooth muscle cells of the arterial segments, and these vacuoles were shown electron microscopically to have double unit membranes, indicating that they were formed by herniation of a part of the adjacent smooth muscle cell body. In the arteries 1–6 h after the end of the contraction, cellular, nuclear and vacuolar membranes and myofilaments of the medial muscle cells were partially lost. 12–24 h after the contraction the arteries exhibited necrosis and desquamation of endothelial cells and platelet adhesion. In the media, smooth muscle cells were completely deprived of cell membranes, myofilaments, nuclei, intracytoplasmic organelles other than mitochondria, and vacuolar membranes. The cytoplasm was filled with fine granular and granulo-vesicular material, and fibrin insudation was observed in these severely damaged cells. Arterial contraction may be an important factor in the induction of arterial lesions. 相似文献
76.
Ueno Shu-ichi; Kondoh Keiji; Komure Yasunori; Komure Osamu; Kuno Sadako; Kawai Jun; Hazama Fumitada; Sano Akira 《Human molecular genetics》1995,4(4):663-666
An unstable expansion of CAG repeat in the coding region ofthe DRPLA gene on chromosome 12p is the mutation specific forhereditary dentatorubralpallidoluysian atrophy (DRPLA). We studiedthe CAG expansion in brain and other tissues from six unre latedDRPLA patients. The CAG repeat lengths showed distinct difterencesbetween tissues. The sizes of the CAG expansion in various regionsof the brain except the cerebellum were generally larger byseveral repeats than in other peripheral tissues. Brain samplesshowed greater variation of the expansion compared with othertissues, but neither the size of the CAG expansion nor the degreeof CAG repeat variation parallels the detailed findings of neuropathologicalinvolvement. We conclude that somatic instabilities of the CAGrepeat cause tissue variability of the CAG repeat size in DRPLAbut other region or cell type-specific factors would be involvedto explain the selectivity of cell damage in DRPLA. 相似文献
77.
Keiji Suzuki 《Pathology international》1982,32(6):1085-1092
A case of basal cell adenoma in the left parotid region of a 45 years old male was reported. The tumor measured 1.1 cm × 0.9 cm, was spherical and covered with a fibrous capsule. Histologically, it was a monomorphic adenoma, forming solid, trabecular, tubular and acinic structure. The tumor cells secreted PAS-positive substance. Electron microscopically, the tumor consisted of three kinds of cells - secretory cells containing electron-dense secretory granules, non-secretory cells, and myoepithelial cells. The acinus was formed of single-layered secretory cells, in the base of which myoepithelial cells were observed. The tubulus was formed of both secretory and non-secretory cells, and myoepithelial cells were found in the base of the tubules. The interstitium was narrow, and was composed of a small amount of collagen fibers, myoepithelial cells, and basement membrane-like substance. 相似文献
78.
79.
Experimental infection and immune response of guinea pigs with varicella-zoster virus. 总被引:3,自引:0,他引:3 下载免费PDF全文
An immune response (fluorescent antibody to membrane antigen) was detected in guinea pigs inoculated with varicella-zoster virus (VZV) adapted to guinea pig embryonic cells, including the Oka vaccine strain, even when inoculation was by an external route, i.e., nasal or corneal. Live or UV-inactivated virus having the same virus titer before irradiation was administered to guinea pigs by the corneal route, and antibody induction was detected only with live virus. The transmission of VZV from infected guinea pigs to noninfected ones was suggested by the appearance of antibody in the serum of the latter, who were kept in the same cage. The time course of the appearance of humoral and cellular immune responses in guinea pigs was examined by the fluorescent antibody to membrane antigen test and the skin reaction, with varicella antigen representing delayed-type hypersensitivity. When VZV was injected subcutaneously, skin reaction appeared as early as 4 days after inoculation, which preceded the appearance of detectable antibody by 2 to 6 days. In in vitro studies, the Oka vaccine showed a higher adsorption rate and better growth in guinea pig embryonic cells than did other wild-type strains when assayed by the infectious center assay. These results suggest that a system of VZV adapted to guinea pig cells and guinea pigs provides a good animal experimental model for immunological study of VZV infection. 相似文献
80.
Keiji Nagai Yukihiko Ueno Nobuo Takamiya Masao Kaneko 《Macromolecular chemistry and physics.》1995,196(4):1241-1250
The photoluminescent Ru(bpy) complex was dispersed in a polysiloxane film containing 2,2′-bipyridine (bpy) pendant groups. The unusually long photoluminescence lifetime of the Ru(bpy) (1,94 μs at 25°C) and the blue-shifted photoluminescent wavelength suggest a rigid polymer matrix. The fluorescence yield becomes lower with higher probe concentration, indicating concentration quenching. According to the analysis based on Stern-Volmer plots, the quenching obeys a mechanism composed of both static and dynamic processes. A statistical intermolecular distance distribution between the probes was used to interpret the results in terms of static and dynamic quenching. It is shown that in the present system the dispersed complexes diffuse slightly during the excited state. 相似文献