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991.
Ola Söderberg 《Medical oncology (Northwood, London, England)》1998,15(2):73-78
Although chronic lymphocytic leukaemia of B-cell type (B-CLL) is the most common form of leukaemia in the Western world, several questions about the biology of B-CLL remain to be clarified. To obtain a conceptual model for B-CLL, defined as a relentless accumulation of resting B-CLL cells, it is particularly relevant to ask which cell type is the normal counterpart of B-CLL; what is the site of proliferation; which signals are involved in the recruitment and induction of proliferation and which signals contribute to the survival of the B-CLL cells? The significance of the studies on B-CLL cellsin vitro for the interpretation of thein vivo situation may be questioned since they oversimplify the multiple and complex cellular interactions that occurin vivo. However, thein vitro studies have been instrumental in elucidating signals that may regulate growth, differentiation and survival of B-CLL cells. This knowledge, herein reviewed, can be used to put forward a hypothesis on B-CLL cell regulationin vivo. 相似文献
992.
Vascular cell adhesion molecule 1 (VCAM-1) is a member of immunoglobulin superfamily. The principal ligand for VCAM-1 is integrin
α4β/VLA-4 (very late antigen 4). It was reported that VCAM-1 was expressed on macrophages and dendritic cells, but little
is known about its function on these professional antigen presenting cells (APC). The present study was performed to investigate
the expression of VCAM-1 on macrophages and the role of VCAM-l/VLA-4 in the activation of allogenic T cells by murine macrophages.
We analyzed VCAM-1 expression on peritoneal macrophages and macrophage cell line J774A.1 by fluorescence-activated cell sorting
(FACS). Using neutralizing antibodies, we further analyzed the role of VCAM-l/VLA-4 interaction in macrophage and allogenic
T cell mixed lymphocyte reaction (MLR). We found that VCAM-1 was constitutively expressed on macrophages and its expression
level was upregulated by soluble tumor associated antigen (freeze-thaw lysates of FBL-3 leukemia cells) and TNF-a. In MLR
assays, we observed that blocking VCAM-l/VLA-4 interaction with anti-VCAM-1 or anti-VLA-4 mAbs caused significant inhibition
of the proliferative response and IL-2 production. These results suggest that VCAM-lon macrophages not only facilitates the
cell-to-cell contact through adhesive interaction but also plays a role in the costimulation of T cells via its interaction
with VLA-4 on the T cells.
This work was supported by grants from the National Natural Science Foundation of China.No. (39730420).
This is one of papers of the special issue on gene therapy research (Chin J Cancer Res Vol. 9 No. 4 December, 1997). 相似文献
993.
E Le Prisé 《Cancer radiothérapie》1998,2(6):763-770
Prognosis of œsophageal cancer is poor. There have been phase II–III trials of postoperative chemotherapy with the aim of improving survival. Chemoradiotherapy seems more promising than both chemotherapy and radiotherapy alone. In contrast, better results obtained with chemoradiotherapy were associated with an increase in morbidity and mortality, and finally overall survival was uncommonly improved. It is necessary to implement new multidisciplinary randomised trial. 相似文献
994.
白细胞介素Ⅱ联合加温化疗治疗癌性腹腔积液 总被引:1,自引:0,他引:1
1995年始采用随机分组方法,比较白细胞介素Ⅱ与加温顺铂、5-氟尿嘧啶联合(治疗组)及单用顺铂、5-氟尿嘧啶(对照组)腹腔内灌注治疗癌性腹腔积液43例,结果显示:治疗组有效率为90.9%,对照组有效率为61.9%,P<0.05。生存质量方面治疗组明显提高,P<0.05。两组毒副反应均较轻,P>0.05无显著性差异,结论:白细胞介素Ⅱ与加温顺铂、5-氟尿嘧啶联合腹腔灌注治疗癌性腹腔积液,可能有协同、相加作用,是有效、简便、毒副反应小的治疗手段 相似文献
995.
Zusammenfassung. Die Klonierung, Sequenzierung und Produktion von hochreinen Allergenen bietet die Möglichkeit, perfekt standardisierte Allergenpräparate herzustellen. Die Entwicklung eines neuen Klonierungssystems, das auf filamentösen Phagen basiert, führte zu einer schnellen Isolierung und Charakterisierung von Aspergillus fumigatus-Allergenen. Die auf diesem Weg rekombinant hergestellten Proteine wurden serologisch und klinisch geprüft und ihr routinemä-ßiger Einsatz im ImmunoCAP-System evaluiert. Es gelang eine quantitative Übereinstimmung zwischen Hauttestergebnissen und Serologie nachzuweisen, welche das Potential rekombinanter Allergene in der Diagnostik allergischer Krankheiten aufzeigt. Darüber hinaus trägt die Charakterisierung der Pilzallergene wesentlich zum Verständnis der moiekularen Natur der allergieauslösenden Komponenten bei Zum jetzigen Zeitpunkt können, abgesehen von Proteinen mit unbekannten biologischen Funktionen, die Pilzallergene in zwei Klassen eingeteilt werden: 1. Spezies-spezifische sezcrnierte Allergene und 2. cytoplasmatische, hoch konservierte Proteine. Diese letztgenannten Pilzallergene zeigen auch zu Proteinen aus phylogenetisch weit entfernten Organismen weitreichende Sequenzhomologien. Neben der daraus zu erwartenden IgE-Kreuzreaktivität findet man in einigen Fällen auch eine Kreuzreaktivität mit den homologen humanen Proteinen, was auf Autoimmunreaktionen, bei Pilzalleigien hindeutet. Summary. Cloning, sequencing and production of highly pure recombinant allergens allows to produce perfectly standardised allergen preparations. The development of a new cloning system based on filamentous phage allowed the fast isolation and characterisation of allergens from the fungus Aspergillus fumigatus. The produced recombinant allergens were tested in serological and clinical studies as well as for their performance for routine assessments in the ImmunoCAP-system. Thereby, a perfect correlation between skin test results and serology was found showing the potential of recombinant allergens for the diagnosis of allergic diseases. Moreover, the characterisation of fungal allergens substantially contributes to our understanding of the molecular nature of proteins involved in the elication of allergic reactions. Apart from allergenic proteins with unknown biological function, fungal allergens can be subdivided into two classes: 1. Species-specific, secreted proteins and 2. cytoplasmic, even in phylogenetically distant organisms, well conserved proteins. These fungal allergens show extended sequence similarity, a high level of IgE cross-reactivity and in some cases also cross-reactivity with homologous human proteins indicating autoimmune reactions involved in fungal allergy. 相似文献
996.
We investigated the type of T cell response involved in Meth A tumor rejection in primary immune and hyperimmune syngeneic mice. It was found that a CD4+ T cell-mediated delayed-type hypersensitivity (DTH) response activating non-specific killer cells such as macrophages, NK and LAK cells, without a specific CD8+ cytotoxic T lymphocyte (CTL) response, was the major immune response leading to Meth A tumor rejection in primary immune mice. In contrast, the specific CD8+ CTL response was the major response leading to the tumor rejection, in addition to CD4+ T cell-mediated DTH response, in hyperimmune mice. Analysis of CD4+ T cell clones established from primary immune and hyperimmune spleen cells indicated that a CD4+ T cell clone (C9) of primary immune mice (although only one clone was established) was of Th1 type, and induced cytotoxicity in accessory cells by classic DTH in vitro. Eight CD4+ T cell clones were established from hyperimmune spleen cells. Six out of the eight clones were of the Th2 type and two were Th0-like. However, no Th1-type CD4+ T cell clone was established from hyperimmune spleen cells. All of these CD4+ T cell clones, even the Th2-type clones, were capable of inducing cytotoxicity in vitro in T cell-depleted accessory cells, as in an in vitro DTH response. We postulate on the basis of these results that the T cell response leading to Meth A tumor rejection in vivo sequentially changed from a CD4+ T cell-mediated classic DTH response to a CD8+ CTL response, in addition to a cellular response mediated probably by Th2-type cells, during the process of repeated immunization. 相似文献
997.
52例阴虚阳虚患者外周血混合白细胞糖皮质激素受体的实验观察 总被引:3,自引:0,他引:3
按“虚证辨证参考标准”,筛选出52例典型的阴虚或阳虚患者,另设正常组20例。分别测定3组外周血白细胞、血浆皮质醇及外周血混合白细胞糖皮质激素受体(GR)。结果表明,3组间白细胞、血浆皮质醇差异无显著性(P>0.05),而阴虚、阳虚两组GR值明显低于正常组,差异均有显著性((P<0.01),且阳虚组与阴虚组比较,差异亦有显著性(P<0.05)。提示GR减少可能是典型阴虚阳虚证发展到一定程度的共同病理改变,而GR减少幅度上的差异可能是两者临床表现不一致的病理基础之一。 相似文献
998.
999.
血小板因子4对巨核细胞的保护作用及其在肿瘤化疗中的意义 总被引:1,自引:0,他引:1
目的:研究血小板因子4对造血细胞的艇及其机制。方法:用液体或半固体培养法及流式细胞术测定血小板因子4对CD34阳性脐血细胞的增殖与分化的作用。结果:血小反因子4可逆性地抑制CD34阳性细胞向巨核细胞的发育。这种抑制可保留更多的巨核系干细胞并使其对5-氟尿嘧啶具有更强的抗性。血小板因子4还可抑制的血小板生成素诱导的巨核细胞生长。结论:血小板因子4通过调控血小板生成素的作用而使一些巨核细胞祖细胞 发育 相似文献
1000.
给幼龄大鼠注射10IU PMSG,48h后注射7IU hCG,或者hCG加不同剂量的催乳素(PRL).在不同时间取出卵巢,检查输卵管中卵子数和卵巢不同细胞中组织型纤溶酶原激活因子(tPA)和抑制因子(PAI-1)mRNA含量和活性.结果表明:PRL减少hCG诱发的排卵数并有明显剂量和时间抑制曲线.当hCG注射24h后,在两组动物输卵管的卵子数无明显差异.PRL同时抑制hCG所诱发的颗粒细胞tPA表达;与少匕相反PRL还能显著刺激膜一间质细胞PAI-1mRNA表达.上述实验结果表明,PRL只暂时延缓而不是完全抑制hCG诱发的大鼠排卵.上述作用可能是通过抑制纤溶酶激活系统在卵巢中的表达引起的. 相似文献