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991.
为了解先天性肾上腺皮质增生症患者的21-羟化酶CYP21B基因中Ile~(172)→Asn错义突变的发生率,根据放大受阻突变体系(Amplificationrefractorymutationsystem,ARMS)的要求,设计了3种引物:5'd(TTGGGAGACTACTCCCTGCTCT)3'(共同引物)、5'd(AGGTGAGGTAACAGA)3'(正常引物)、5'd(AGGTGAGGTAACAGT)3'(突变引物),在7例患儿中进行了检测,发现具有本突变者3例。对其中一例进行的家系分析,结果提示:这组引物有快速、简便的优点,不需使用同位素就能对具有Ile~(172)→Asn变异的高危家庭成员作产前诊断。 相似文献
992.
Nishimura Hiroyuki; Hattori Susumu; Ueda Genjiro; Abe Masaaki; Yang Kwangseok; Nozawa Shingo; Okamoto Hiroshi; Zhang Danqing; Tsurui Hiromichi; Hirose Sachiko; Shirai Toshikazu 《International immunology》1995,7(7):1115-1123
Using two mAb, one specific to the alternative exon 6-dependentepitope of CD45 molecules(JH6.2) and one a natural thymocytotoxicautoantibody (NTA) with an unknown reactive epitope (NTA260),we subdivided splenic CD4+ T cells from 2-month-old BALB/c miceinto five phenotypically distinct subsets. CD45RC+NTA260–(SI) cells were phenotypically analogous to CD4+ T cells predominatingin newborn mice and produced a significant amount of IL-2, butnot so IL-4, IL-10 or IFN- when stimulated with immobilizedanti-CD3 mAb in vitro. They appeared to consist mainly of naiveThP cells. The CD45RC+;NTA260+ (S II) subset also produced IL-2,but not other cytokines; however, the IL-2 levels produced weremuch higher than seen with the S I subset, thereby suggestingthe predominance of further maturated ThP cells. The D45RC–NTA260+(S III) subset mainly produced IL-4, IL-10, IFN- and less IL-2,and contained memory cells that helped the secondary antibodyresponse to a recall antigen, and hence contained Th2 and probablya mixture of Th0 and Th1 cells. The CD45RC–NTA260–(S IV) subset was a poor responder to the immobilized anti-CD3mAb. The CD45RCbrightNTA260dull(S V) subset consisted of a smallnumber of cells that were phenotypically analogous to activatedCD4+ T cells. While an age-associated decrease in the proportionof S I and less markedly in S II and in turn increase in S IIIsubsets of CD4+ T cells occurred in normal BALB/c mice, autoimmunedisease-prone (NZBxNZW)F1 mice showed a marked age-associateddecrease in the proportion of not only S I, II but also IIIsubsets. As aged (NZBxNZW)F1 mice carry CD4+ T helper cellsfor IgG anti-DNA antibody production, such age-associated polarizationto the S IV subset appears to be critical in the pathogeneslsof autoimmune disease in these mice. 相似文献
993.
Splenic ultrasound was performed and spleen scans obtained by a rectilinear scanner after injection of In-113m-labelled heat damaged red cells on 14 patients with various haematological disorders. Correlation was assessed between the measured volume of the operatively removed spleens, their volumes as calculated from the ultrasound data, and their preoperative dimensions of length, circumference, and area on the scans. The relation of scan to volume was best defined by an equation V = 9.88A - 534, where V = volume of spleen (cm3) and A = area (cm2) on posterior scan. The mean percentage difference between calculated and actual spleen volume was 0.2 (SD 6.7)%. Average spleen density was established as 1.04 g/cm3. The formula was shown to be reliable in the range of splenic area c 73-450 cm2--that is, volume c 185-4000 cm3. This range includes the average normal sized spleens and the splenomegalies that are most often found in clinical practice. The formula is not valid when the spleen is smaller than normal. As the method depends on measurement of the spleen image shown by scintigraphs, it cannot be used when there is functional asplenia. 相似文献
994.
我们观察了幼年小白鼠腘淋巴结淋巴窦的超微结构,窦壁由腔面向外一般出3层构成:(1)一层连续的内皮;(2)由一薄层细胞间质构成的基膜;(3)一层外膜网状细胞及其扁平的突起。内皮细胞核扁圆,异染色质细小,核仁不明显,胞质极薄,含粗面内质网极少,而有大量的吞饮小泡。细胞邻接处相互重叠或嵌合,有20nm宽的间隙相隔。有的地方可见不发达的细胞连接。当巨噬细胞或淋巴细胞穿越内皮时,可出现临时性间隙,内皮边缘与穿越细胞相贴。基膜由电子透明的无定形基质及细的胶原原纤维构成。外膜网状细胞的核异染色质较多,核仁明显,胞质丰富,含许多粗面内质网而很少吞饮小泡。外膜网状细胞之间常见0.5μm宽的间隙。在窦腔内有巨噬细胞、淋巴细胞及星状的网状细胞等。由于小白鼠腘淋巴结的淋巴窦小,故窦内星形的网状细胞很少,其超微结构特点,与外膜网状细胞及淋巴组织内的网状细胞相似,在突起的切面上,常见包有小束的胶原原纤维。巨噬细胞较多,形态不规则,常贴附于内皮细胞表面,核椭圆,常有凹陷,胞质丰富,含许多溶酶体。在取材前1h,于足垫注射中国墨汁的小鼠,巨噬细胞吞噬了大量粗的墨汁颗粒。本文认为,淋巴窦壁可能具有一定的屏障作用。 相似文献
995.
Y. Zhang M. Schluep S. Frutiger G. J. Hughes M. Jeannet A. Steck T. Barkas 《European journal of immunology》1990,20(12):2577-2583
The response of human T lymphocytes against the nicotinic acetylcholine receptor (AChR) was studied in five patients with myasthenia gravis (MG) and in six healthy donors using either native Torpedo AChR or recombinant protein derived from the mammalian AChR α subunit (X4, residues 6–216 of mouse AChR α subunit). The present study demonstrates that (a) AChR-specific T helper cell lines can be generated from MG patients [either from peripheral blood lymphocytes (PBL) or from thymocytes] as well as from PBL of normal controls, (b) lymphocytes from MG patients, but not from controls, recognize the mammalian AChR but not the Torpedo receptor, (c) in humans, the HLA-DR2-associated T cell epitope is probably located in the region of residues 162–216 of the AChR α subunit and (d) there is a considerable heterogeneity of autoreactive T cell responses: (i) Tcell lines from different HLA-type donors have distinct epitope profiles; (ii) the epitope specificity of the PBL-derived T cell line is different from that of the thymocyte-derived line; (iii) the epitope specificities of patient-derived T cell lines are different from those generated from normal controls who share the same HLA phenotype. 相似文献
996.
K.-M. Zhang Ping Hu Shang-Wu Wang Leon D. Wright Andrew S. Wechsler John A. Spratt F. N. Briggs 《Pflügers Archiv : European journal of physiology》1998,435(4):511-517
Chronic administration of salbutamol induced expression of hybrid fibers in canine skeletal muscles. Fast-twitch fibers expressed
SERCA2a (the slow-twitch isoform of sarcoplasmic reticulum Ca2+-ATPase) and slow-twitch fibers expressed SERCA1 (the fast-twitch isoform of the Ca2+-ATPase). The proportion of fibers that became hybrid increased from a small percentage in the control muscles to 30% in the
predominantly fast-twitch latissimus dorsi and to 45% in the predominantly slow-twitch vastus intermedius. In contrast to
this response by the SERCA genes the phospholamban gene response was muscle specific. The fraction of fibers that expressed
phospholamban decreased slightly in the latissimus dorsi while increasing moderately in the vastus intermedius. The effects
of chronic neurostimulation of the latissimus dorsi on SERCA1, SERCA2a and phospholamban levels were mostly blocked by salbutamol.
While 100% of fibers from neurostimulated muscles expressed phospholamban, only 51% of the fibers from the neurostimulated
and salbutamol-treated muscles expressed it. In the neurostimulated muscle, very few muscle fibers expressed SERCA1a while
61% of the fibers that received salbutamol expressed it, albeit as hybrid fibers. The levels of SERCA2a in response to these
interventions were just the opposite. In the neurostimulated muscle 37.5% of fibers were hybrid and 62.5% expressed SERCA2a
only. With co-administration of neurostimulation and salbutamol, 61.3% of fibers were hybrid and 38.7% expressed SERCA2a only.
Received: 4 July 1997 / Received after revision: 16 October 1997 / Accepted: 30 October 1997 相似文献
997.
Ping Zhang Zhenhua Sun Guang Li Yugang Zhuang Mengxiam Ding Zhiliu Feng 《Macromolecular chemistry and physics.》1993,194(7):1871-1877
The structure and miscibility of polyimide PBPI-E/PTI-E blends were studied by wide- and small-angle X-ray scattering and dynamic mechanical analysis, where PBPI-E is a biphenyldianhydride-based polyimide, and PTI-E is a polyimide from 4,4′-thiodiphthalic anhydride and 4,4′-oxydianiline. The results obtained show that there exists a paracrystalline structure in the blends with high content of PBPI-E, but this does not affect the miscibility of the blends. The blends are miscible over the entire composition range, since only one Tg was observed for each blend. Meanwhile, the segregation of PTI-E during crystallization of PBPI-E in the blends is interlamellar. 相似文献
998.
Conserved RARE localization in amphioxus Hox clusters and implications for Hox code evolution in the vertebrate neural crest. 总被引:3,自引:0,他引:3
Hiroshi Wada Hector Escriva Shicui Zhang Vincent Laudet 《Developmental dynamics》2006,235(6):1522-1531
The Hox code in the neural crest cells plays an important role in the development of the complex craniofacial structures that are characteristic of vertebrates. Previously, 3' AmphiHox1 flanking region has been shown to drive gene expression in neural tubes and neural crest cells in a retinoic acid (RA)-dependent manner. In the present study, we found that the DR5-type RA response elements located at the 3' AmphiHox1 flanking region of Branchiostoma floridae are necessary and sufficient to express reporter genes in both the neural tube and neural crest cells of chick embryos, specifically at the post-otic level. The DR5 at the 3' flanking region of chick Hoxb1 is also capable of driving the same expression in chick embryos. We found that AmphiHox3 possesses a DR5-type RARE in its 5' flanking region, and this drives an expression pattern similar to the RARE element found in the 3' flanking region of AmphiHox1. Therefore, the location of these DR5-type RAREs is conserved in amphioxus and vertebrate Hox clusters. Our findings demonstrate that conserved RAREs mediate RA-dependent regulation of Hox genes in amphioxus and vertebrates, and in vertebrates this drives expression of Hox genes in both neural crest and neural tube. This suggests that Hox expression in vertebrate neural crest cells has evolved via the co-option of a pre-existing regulatory pathway that primitively regulated neural tube (and possibly epidermal) Hox expression. 相似文献
999.
Sun Y Zhou H Zhang Q Wu X 《Artificial cells, blood substitutes, and immobilization biotechnology》2000,28(2):173-180
Lomustine (CCNU) microcapsules was prepared by improved recoacervation method, then mixed microcapsules with 0.7% collagen swelling solution to prepare the emulsion, spreaded the emulsion on the plate to form membrane and cross-linked it, the membrane would be planted into body and was expected to release at steady speed. The concentration of CCNU and the CCNU content of microcapsules were measured by ultraviolet spectrophotometry to observe the release of CCNU be slow and constant, approach to 0-class release approximately. 相似文献
1000.
新型微波热疗机研制及其临床应用 总被引:6,自引:0,他引:6
重点对新型电脑微波热疗机的构成、测温控温方案进行了研究。采用自适应广义预测控制算法对热疗温度进行控制,解决了因更换不同辐射器导致对象特性变化使控制性能降低的问题,从而得到了满意的疗效。文中介绍了该仪器关键的硬件、软件设计,基本的特点和临床应用 相似文献