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51.
Morales A Morimoto S Díaz L Robles G Díaz-Sánchez V 《The Journal of endocrinology》2008,197(2):309-314
Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) is an endothelial cell mitogen, expressed essentially in steroidogenic cells. Recently, the expression of EG-VEGF in normal human pancreas and pancreatic adenocarcinoma has been demonstrated. Epidemiologically, pancreatic carcinogenesis is more frequent in males than females, and given that androgen receptors and testosterone biotransformation have been described in pancreas, we hypothesized that testosterone could participate in the regulation of EG-VEGF expression. In this study, we investigated the regulation of EG-VEGF gene expression by testosterone in normal rat pancreatic tissue and rat insulinoma cells (RINm5F). Total RNA was extracted from rat pancreas and cultured cells. Gene expression was studied by real-time PCR and protein detection by immunohistochemistry. Serum testosterone was quantified by RIA. Results showed that EG-VEGF is expressed predominantly in pancreatic islets and vascular endothelium, as well as in RINm5F cells. EG-VEGF gene expression was lower in the pancreas of rats with higher testosterone serum levels. A similar effect that was reverted by flutamide was observed in testosterone-treated RINm5F cells. In summary, testosterone down-regulated EG-VEGF gene expression in rat pancreatic tissue and RINm5F cells. This effect could be mediated by the androgen receptor. To our knowledge, this is the first time that a direct effect of testosterone on EG-VEGF gene expression in rat pancreas and RINm5F cells is demonstrated. 相似文献
52.
Identification of simultaneous mutation of fibrinogen alpha chain and protein C genes in a Japanese kindred 总被引:2,自引:0,他引:2
Watanabe K Shibuya A Ishii E Kurihara M Inoue S Ono M Wada Y Wakiyama M Zaitsu M Iida H Muraoka K Kinoshita S Hamasaki N 《British journal of haematology》2003,120(1):101-108
Afibrinogenaemia usually induces a bleeding tendency during infancy, whereas protein C deficiency increases susceptibility to thrombosis in children or adolescence. Mutations of these genes have been, therefore, established as independent risk factors for coagulation disorders. We describe the homozygous mutation of the fibrinogen alpha chain gene and additional heterozygous mutation of the protein C gene in a male infant who showed prolonged umbilical bleeding after birth. On examination, the plasma fibrinogen was undetectable, and the activity and antigen level of protein C were reduced. The patient showed no fibrinogen Aalpha chain as well as Bbeta and gamma chains by Western blotting. The sequencing analysis showed the homozygous deletion of 1238 bases from intron 3 at position 2008 to intron 4 at position 3245 in the fibrinogen alpha chain gene. Both parents were heterozygous carriers of this mutation. In this patient, an additional mutation was also detected in the protein C gene: the heterozygous deletion of exon 7 at position 6161-6163 or 6164-6166, resulting the deletion of one amino acid (Lys150 or 151). His mother was also a carrier of this mutation. As the simultaneous mutation of the fibrinogen alpha chain and protein C genes has not been previously reported, the influence of the interaction between these two mutations on the clinical manifestations of this patient should be carefully monitored for a long period. 相似文献
53.
Wide cross-species aminoacyl-tRNA synthetase replacement in vivo: yeast cytoplasmic alanine enzyme replaced by human polymyositis serum antigen. 总被引:3,自引:0,他引:3 下载免费PDF全文
T L Ripmaster K Shiba P Schimmel 《Proceedings of the National Academy of Sciences of the United States of America》1995,92(11):4932-4936
Because of variations in tRNA sequences in evolution, tRNA synthetases either do not acylate their cognate tRNAs from other organisms or execute misacylations which can be deleterious in vivo. We report here the cloning and primary sequence of a 958-aa Saccharomyces cerevisiae alanyl-tRNA synthetase. The enzyme is a close homologue of the human and Escherichia coli enzymes, particularly in the region of the primary structure needed for aminoacylation of RNA duplex substrates based on alanine tRNA acceptor stems with a G3.U70 base pair. An ala1 disrupted allele demonstrated that the gene is essential and that, therefore, ALA1 encodes an enzyme required for cytoplasmic protein synthesis. Growth of cells harboring the ala1 disrupted allele was restored by a cDNA clone encoding human alanyl-tRNA synthetase, which is a serum antigen for many polymyositis-afflicted individuals. The human enzyme in extracts from rescued yeast was detected with autoimmune antibodies from a polymyositis patient. We conclude that, in spite of substantial differences between human and yeast tRNA sequences in evolution, strong conservation of the G3.U70 system of recognition is sufficient to yield accurate aminoacylation in vivo across wide species distances. 相似文献
54.
Yagi S Akaike M Fujimura M Ise T Yoshida S Sumitomo Y Ikeda Y Iwase T Aihara K Azuma H Kurushima A Ichikawa Y Kitagawa T Kimura T Nishiuchi T Matsumoto T 《Internal medicine (Tokyo, Japan)》2008,47(12):1113-1116
Lactobacillus (LB) is a gram-positive rod-shaped bacterium that inhabits the oral cavity, gastrointestinal tract, vagina and nasal cavity. Although LB plays a role in the prevention of infections caused by pathogenic bacteria, it causes some critical infectious diseases such as infective endocarditis (IE). IE due to LB is rare; however, early diagnosis and early treatment are important because of its high mortality rate. We report the onset of IE after otologic treatment in a heavy drinker of alcohol, the second case of IE due to LB in Japan. 相似文献
55.
Daisuke Imai Kenei Furukawa Hiroaki Shiba Shigeki Wakiyama Takeshi Gocho Katsuhiko Yanaga 《International surgery》2013,98(2):160-163
A 41-year-old male patient with hepatitis B underwent right tri-segmentectomy and total caudate lobectomy for a huge hepatocellular carcinoma associated with complete occlusion of the inferior vena cava with thrombosis of the infrahepatic inferior vena cava due to tumor compression. Five months later, he was readmitted for ascites and hyperbilirubinemia. Venography revealed stenosis and tortuosity of the left hepatic vein and the inferior vena cava, for which balloon angioplasty of the left hepatic vein and the inferior vena cava was performed using an 8-mm and 10-mm balloon, respectively. The left hepatic venous pressure decreased from 65 mmHg to 25 mmHg after dilatation. The patient made a satisfactory recovery thereafter and remains well with normal liver functions and without ascites. Balloon angioplasty may be useful for liver failure due to hepatic vein stenosis after hepatic resection. 相似文献
56.
Hida S Chikamori T Tanaka H Igarashi Y Shiba C Usui Y Hatano T Yamashina A 《Circulation journal》2012,76(8):1942-1952
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59.
Ishizaki Atsushi Mishiro Kenji Shiba Kazuhiro Hanaoka Hirofumi Kinuya Seigo Odani Akira Ogawa Kazuma 《Annals of nuclear medicine》2019,33(4):244-251
Annals of Nuclear Medicine - Somatostatin receptors are highly expressed in neuroendocrine tumors, and many radiolabeled somatostatin analogs for diagnosis and treatment have been developed. To... 相似文献
60.
We re-evaluated the criteria for waist circumference to predict the accumulation of the components of metabolic syndrome. We used data for 3,185 Japanese, aged 20-79 years. Metabolic syndrome has recently been redefined by a new criterion in Japan, in which waist circumference cutoff points, i.e. 85 cm for men and 90 cm for women, are employed. Among the 3,185 Japanese considered in the present study, 335 men (26.8%) and 69 women (3.6%) were diagnosed as having metabolic syndrome. A cutoff point as a predictor for 2 or more components of metabolic syndrome was evaluated by sensitivity/specificity and a receiver operating characteristic (ROC) curve. The optimal point was estimated as being approximately 85 cm of waist circumference in men and 75 cm in women. We therefore recommend a cutoff value, 75 cm of waist circumference, for the criterion of metabolic syndrome in women. 相似文献