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991.
992.
巯基物质在氧自由基损伤离体胃粘膜细胞中的作用 总被引:7,自引:0,他引:7
本文用离体胃粘膜细胞研究了细胞内流基物质在活性氧诱发细胞损伤中的作用。实验采用pronase-EDTA法分离大鼠胃粘膜细胞并进行短期孵育,以黄嘌呤氧化酶(XO)-黄嘌呤(X)系统产生氧自由基损伤细胞。实验结果表明,用XO-X损伤胃粘膜细胞时,细胞存活率显著降低,乳酸脱氨酶(LDH)漏出量增多,同时细胞内非蛋白质巯基(NPSH)和蛋白质巯基(PSH)含量均不同程度地下降;N-乙基顺丁烯二酰亚胺(NEM)在耗竭细胞内NPSH和PSH的同时,引起细胞死亡和LDH漏出增加,这一作用与NEM的作用时间和浓度是显著依从关系;在细胞孵育液中预先加入含-SH的化合物还原型谷胱甘肽(GSH)或半胱胺,可剂量依赖性地减轻XO-X引起的细胞损伤。上述结果提示,胃粘膜细胞内的巯基物质在自身防御机制中具有重要作用,氧自由基损伤胃粘膜细胞的机制之一可能与破坏细胞内巯基的稳态有夫。 相似文献
993.
The distribution of endocrine cells in the mucosa of the gastrointestinal tract of the house musk shrew,Suncus murinus (Insectivora) 总被引:1,自引:0,他引:1
Yoko Kanamori Saburo Nakazawa Dr. Junzoh Kitoh Munemitsu Hoshino 《Cell and tissue research》1989,258(2):365-371
Summary The distribution of endocrine cells in the gastrointestinal tract of the house musk shrew, Suncus murinus (Family Soricidae, Order Insectivora) was studied immunohistochemically. The hormones investigated were gastrin, cholecystokinin (CCK), somatostatin, secretin, glucagon, gastric inhibitory polypeptide (GIP), motilin and neurotensin. In the gastric mucosa, gastrin and somatostatin cells were only found in the pyloric regions, and no other hormonal cell-types were observed. In the intestinal mucosa, the largest number of endocrine cells belonged to the gastrin and glucagon/glicentin cell-types, whereas CCK-33/39 and secretin cells were the least numerous. Numbers of other cell-types were intermediate between these two groups. The gastrin and GIP cells were mostly localized in the proximal portion of the intestine, decreasing in number towards the distal portion. The motilin and CCK-33/39 cells were restricted to the proximal half. The glucagon/glicentin and neurotensin cells were most abundant in the middle portion. The somatostatin and secretin cells, although only present in small numbers, were randomly distributed throughout the intestine. This characteristic distribution of gastrointestinal endocrine cells is discussed in comparison with the distribution patterns of other mammals.Dr. Munemitsu Hoshino, who was Professor of the Department of Pathology and directed this study, passed away on May 23rd 1988 相似文献
994.
Adoptive immunotherapy (AIT) for non-hematological malignancies, using HLA-matched donor lymphocytes, has been rarely reported.
For a 35-year-old male patient with peritoneal disseminated advanced gastric cancer, we performed AIT using lymphocytes from
his HLA-matched 37-year-old brother and a streptococcal preparation, OK-432, as an antigen. After the donor had been immunized
by intradermal administration of OK-432, OK-432-reactive lymphocytes were induced in vitro and transferred to the patient
intravenously with OK-432. Low-dose systemic immunochemotherapy, using interleukin-2, 5-fluorouracil and cyclophosphamide,
was concurrently administered with AIT. As a result, the Schnitzler metastasis in the patient reduced in size without any
significant graft-versus-host-related complications. One of the effector mechanisms of therapeutic benefit was suggested to
be cytokine release from the transferred OK-432-reactive lymphocytes. Our findings suggest the safety and efficacy of AIT
using lymphocytes from an HLA-matched sibling and OK-432 as an antigen. Further studies to investigate the use of tumor-associated
antigen and an HLA-matched sibling’s lymphocytes for AIT of advanced cancer are warranted.
Received: 19 May 1997 / Accepted 18 November 1997 相似文献
995.
Jyh-Shi Lin Chi-Wei Lu Chang-Jen Huang Peng-Fyn Wu Daniel Robinson Hsing-Jien Kung Chin-Wen Chi Chew-Wun Wu Wen-Kang Yang Jacqueline J. K. Whang-Peng Wen-chang Lin PhD 《Journal of biomedical science》1998,5(2):101-110
Protein kinases play key roles in cellular functions. They are involved in many cellular functions including; signal transduction, cell cycle regulation, cell division, and cell differentiation. Alterations of protein kinase by gene amplification, mutation or viral factors often induce tumor formation and tumor progression toward malignancy. The identification and cloning of kinase genes can provide a better understanding of the mechanisms of tumorigenesis as well as diagnostic tools for tumor staging. In this study, we have used degenerated polymerase-chain-reaction primers according to the consensus catalytic domain motifs to amplify protein kinase genes (protein-tyrosine kinase, PTK, and protein-serine/threonine kinase, PSK) from human stomach cancer cells. Following amplification, the protein kinase molecules expressed in the gastric cancer cells were cloned into plasmid vectors for cloning and sequencing. Sequence analysis of polymerase-chain-reaction products resulted in the identification of 25 protein kinases, including two novel ones. Expression of several relevant PTK/PSK genes in gastric cancer cells and tissues was further substantiated by RT-PCR using gene-specific primers. The identification of protein kinases expressed or activated in the gastric cancer cells provide the framework to understand the oncogenic process of stomach cancer. 相似文献
996.
对77例胃粘膜活检标本进行银染,显示核仁组成区相关的嗜银蛋白(Ag-NOR),进行计数和统计分析,并对银染标本作电镜观察及能谱分析。结果表明,Ag-NOR 颗粒计数的多少,对胃肿瘤恶性程度的诊断有重要参考价值。电镜证实银染物质定位于核仁组成区,银染阳性区能谱分析显示 Ag 峰,说明银染反应具特异性. 相似文献
997.
Motonori Sairenji Shunsuke Yanoma Hisahiko Motohashi Osamu Kobayashi Kenzou Okada Takashi Okamoto Mamoru Tsukuda Makoto Umeda 《Biotherapy》1993,6(4):283-290
We established a cell line (STKM-1) from tumor cells obtained from carcinomatous pleural effusion of a gastric cancer patient. The lymphocytes separated from her peripheral blood or pleural effusion were cryopreserved and immunological experiments were performed after the establishment of the cell line. They were treated with IL-2 or with both IL-2 and mitomycin C (MMC)-treated autologous STKM-1 cells. The cytolytic activity against STKM-1 cells was elevated in lymphocytes cultured with IL-2, and was more prominently augmented in lymphocytes cultured with both IL-2 and MMC-treated STKM-1 cells. The elevation in cytolytic activity was more marked with pleural effusion lymphocytes than with the peripheral blood lymphocytes. The results suggest that the lymphocytes obtained from the pleural effusion would be an excellent source for adoptive immunotherapy.Abbreviations IL-2
interleukin-2
- LAK
lymphokine activated killer
- MLTC
mixed lymphocyte tumor cell culture
- MMC
mitomycin C
- MoAbs
monoclonal antibodies
- TIL
tumor infiltrating lymphocytes 相似文献
998.
999.
ras原癌基因的点突变是人胃癌发生发展的重要机理之一。利用能表达c-H-ras癌基因反义RNA的质粒,导入人胃癌细胞系BGC-823,研究了ras癌基因反义RNA对人胃癌细胞生长及恶性表型的作用,结果表明,c-H-ras反义RNA可引起BGC-823生长速率及形态的变化,在半固体培养基中细胞集落形成能力减弱,部分地抑制了BGC-823在裸鼠体内的致瘤性。c-H-ras反义RNA对其RNA的过量表达呈特异性抑制作用。 相似文献
1000.
Thermal changes in the gastric evacuation rate of the freshwater sculpin Cottus nozawae Snyder 总被引:1,自引:0,他引:1
Hitoshi Miyasaka Yoichi Kawaguchi Motomi Genkai-Kato Kenji Yoshino Hidejiro Ohnishi Naotoshi Kuhara Yukiyoshi Shibata Tsuyoshi Tamate Yoshinori Taniguchi Hirokazu Urabe Shigeru Nakano 《Limnology》2005,6(3):169-172
We experimentally measured thermal changes in the gastric evacuation rate (GER) of the freshwater sculpin Cottus nozawae Snyder under three water temperature regimes (2°, 7°, and 12°C). Laboratory experiments showed that the GER was accelerated
with increasing water temperature. This result suggests that the daily food rations of fish are more likely to be underestimated
at higher water temperatures if estimation is simply based on the stomach content weight alone. By comparing the GER for various
fish species from subfrigid to temperate streams, we found a general pattern that the GER increases with water temperature,
regardless of taxonomic group or foraging mode. However, the reaction norms of the GER against water temperature showed considerable
interspecific variation. This means that stomach content weight is not comparable as a simple measure for determining the
daily rations among fish species when water temperature regimes are different. To consider the temperature-dependent pattern
of such a physiological phenomenon is important in understanding the feeding ecology of fishes and their roles in material
cycles through food webs in aquatic ecosystems. 相似文献