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排序方式: 共有2721条查询结果,搜索用时 15 毫秒
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Varsha Patki Joe Virbasius William S. Lane Ban-Hock Toh Howard S. Shpetner Silvia Corvera 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(14):7326-7330
Phosphatidylinositol 3-kinases (PI 3-kinases) have been implicated in membrane trafficking in the secretory and endocytic pathways of yeast and mammalian cells, but the molecular mechanisms by which these lipid kinases operate are not known. Here we identify a protein of 170 kDa that is rapidly released from cell membranes in response to wortmannin, a potent inhibitor of mammalian PI 3-kinases. The amino acid sequence of peptides from p170 reveal its identity to early endosomal antigen (EEA) 1, an endosomal antigen with homology to several yeast proteins genetically implicated in membrane trafficking. Immunofluorescence analysis of 3T3-L1 adipocytes with antisera against p170/EEA1 reveal a punctate peripheral pattern that becomes diffuse in response to wortmannin. In vitro, p170/EEA1 binds specifically to liposomes containing PIns(3)P, suggesting that the effect of wortmannin on cells is due to inhibition of PIns(3)P production. Thus, p170/EEA1 may define a family of proteins that mediate the regulatory effects of 3′-phosphoinositides on membrane trafficking in yeast and mammalian cells. 相似文献
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Satomi-Kobayashi Seimi Kawashima Seinosuke Sakoda Tsuyoshi Ueyama Tomomi Hirase Tetsuaki Kawai Miki Toh Ryuji Iwai Kenji Yokoyama Mitsuhiro 《Circulation journal》2004,68(3):247-253
BACKGROUND: Glycogen synthase kinase-3 beta (GSK-3beta) is involved in many cellular processes, such as metabolism, apoptosis, differentiation and proliferation. Insulin-like growth factor-1 (IGF-1), which is well known to have a hypertrophic effect on cardiomyocytes, inactivates (phosphorylates) GSK-3beta in some cell types. The role of GSK-3beta in cardiomyocytes as a negative regulator of cardiac hypertrophy has been recently reported and the present study investigated the role of GSK-3beta in the cardiac hypertrophy of cultivated neonatal rat cardiomyocytes induced by IGF-1. METHODS AND RESULTS: First, the IGF-1 induced signal transduction leading to GSK-3beta in neonatal rat cardiomyocytes was examined. The phosphatidylinositol (PI) 3-kinase/Akt/GSK-3 beta signaling induced by IGF-1 was investigated using inhibitors of PI 3-kinase and Ad AktAA, a dominant negative form of Akt. Furthermore, using Ad MEK DN, a dominant negative form of MEK, it was found that MEK negatively regulates Akt phosphorylation upon IGF-1 stimulation. Next, it was examined whether GSK-3beta acts as a negative regulator in the cardiac hypertrophy induced by IGF-1. Sustained stimulation by IGF-1 caused cardiac hypertrophy in protein synthesis and cellular morphology, and overexpression of unphosphorylatable GSK-3beta (Ad GSK-3beta S9A) repressed these hypertrophic effects of IGF-1. CONCLUSIONS: GSK-3beta may play an important role as a negative regulator of cardiac hypertrophy induced by IGF-1. 相似文献
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Kaname Ishii Yuichi Hayashida Katsuhiro Yoshimoto Hidehiro Tajima Uichiro Fuchisaki Toshiya Takeda Toru Kamata Hirotoshi Miyamori Masahiro Kanno 《Nihon Shokakibyo Gakkai zasshi》2006,103(8):931-935
We report a case of granulocyte-colony stimulating factor producing gastric cancer with multiple liver metastases. A 68-year-old woman who complained of epigastralgia visited our hospital. Upper gastrointestinal endoscopic examination revealed a type-2 gastric cancer. The laboratory data at admission indicated leukocytosis (35,900/microl) and a high level of serum granulocyte-colony stimulating factor (61 pg/mg). Granulocyte-colony stimulating factor producing gastric cancer was diagnosed by immunohistochemistry of biopsy specimen. Since we detected multiple liver metastases, chemotherapy was performed. Granulocyte-colony stimulating factor-producing gastric cancer is relatively rare and we summarize previous reports. 相似文献
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Possible role of cytomegalovirus in the pathogenesis of inflammatory aortic diseases: a preliminary report. 总被引:6,自引:0,他引:6
S Tanaka Y Toh R Mori K Komori K Okadome K Sugimachi 《Journal of vascular surgery》1992,16(2):274-279
To search for possible evidence of a relationship between human cytomegalovirus and aortic diseases, we examined 41 aortic lesions excised at surgery and 16 aortic tissues obtained at autopsy for the presence of cytomegalovirus DNA, by use of polymerase chain reaction. Cytomegalovirus DNA was present in seven (88%) of eight lesions of inflammatory aortic diseases with periaortic fibrosis, five of six inflammatory aneurysms, and all of two aortic occlusive lesions with inflammation. Cytomegalovirus DNA was detected in 20 (61%) of 33 atherosclerotic aneurysms, whereas it was detected in only five (31%) of 16 autopsy samples that showed neither inflammation nor atherosclerosis. Thus the possibility that cytomegalovirus may play a role in the pathogenesis of inflammatory aortic diseases warrants further attention. 相似文献
9.
Kuniaki Nakahara Satoru Shimizu Satoshi Utsuki Sachio Suzuki Hidehiro Oka Kiyotaka Fujii 《Child's nervous system》2007,23(8):863-865
Objects We evaluated whether the presence of lacunar skull deformity (LSD) with myelomeningocele is a predictive factor for subsequent
hydrocephalus development.
Materials and methods We reviewed the clinical and radiological records of 18 infants with myelomeningocele, divided the patients into groups with
(group A, n=9) and without (group B, n=9) ventriculomegaly at birth and assessed whether the presence of LSD was predictive of the necessity for ventriculoperitoneal
shunt (VPS) placement.
Results LSD was present in five group A patients. All nine group A patients underwent VPS placement. Among the group B patients, five
had LSD; they underwent VPS placement. A significantly higher proportion of those with ventricle enlargement or LSD at birth
required VPS placement (p=0.0001).
Conclusion Adding to the ventriculomegaly at birth, the presence of LSD alerts to the necessity to monitor these infants closely to determine
the necessity for VPS placement. 相似文献
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