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81.
Saito H Yamaoka Y Ishizone S Maruta F Sugiyama A Graham DY Yamauchi K Ota H Miyagawa S 《Gut》2005,54(5):584-590
BACKGROUND AND AIMS: The roles of the virD4 and the cagG genes in the cag pathogenicity island of Helicobacter pylori for gastroduodenal pathogenesis are unclear and their roles in vivo have not been examined. METHODS: Seven week old male Mongolian gerbils were inoculated with the wild type H pylori TN2GF4, its isogenic virD4, or cagG mutants. Animals were sacrificed at 4, 12, and 24 weeks after inoculation. Gastric inflammation and H pylori density were evaluated by histology, inflammatory response (as measured by interleukin (IL)-1beta mRNA levels), proliferative activity (as assessed by 5'-bromo-2'deoxyuridine labelling indices), and host systemic reaction (as measured by anti-H pylori IgG antibody). RESULTS: Degree of gastric inflammation, proliferative activity, and mucosal IL-1beta mRNA levels remained low throughout the first 12 weeks in gerbils infected with the virD4 mutants. Degree of gastric inflammation and proliferative activity increased at 24 weeks with the virD4 mutants reaching levels comparative with those seen at four weeks with the wild-type strains. Mucosal IL-1beta mRNA levels were also increased at 24 weeks with the virD4 mutants and levels at 24 weeks were similar between the wild-type and virD4 mutants. In contrast, gerbils infected with the cagG mutants had reduced ability to colonise gerbils, and no or little gastric inflammation or proliferative activity was observed. CONCLUSIONS: Loss of the virD4 gene temporally retarded but did not abrogate gastric inflammation. Loss of the cagG gene abolished gastric inflammation partially via reduced ability to colonise gerbils. Unknown factors related to the type IV secretion system other than CagA may influence gastric inflammation. 相似文献
82.
Kyoji Yamamoto M.D. Keiichi Fujimoto Takashi Matsushiro Keisuke Ota 《Journal of gastroenterology》1990,25(6):758-761
A case of lymphoepithelial cyst in the pancreas was reported. A 64-year-old man without any specific compalints was found
to have a cystic lesion in the anterior portion of the pancreas, as revealed by ultrasonography of the abdomen at an annual
medical examination in 1988. This was dissected easily from the pancreas. Histologically, it was diagnosed to be a benign
lymphoepithelial cyst in the pancreas. Cysts of this type are rare, and their histogenesis is also not well understood. 相似文献
83.
A case of coexisting malignant carcinoid tumor and adenocarcinoma in the papilla of Vater 总被引:1,自引:0,他引:1
J Misonou M Kanda T Kitagawa T Ota E Muto M Nenohi T Atsuta 《Gastroenterologia Japonica》1990,25(5):630-635
A 47-year-old Japanese woman in whom obstructive jaundice had already been diagnosed, was found to have a dome-shaped elevated tumor approximately 3 cm in diameter located in the area very close to the papilla of Vater on endoscopical and radiographical investigations. Histopathologically, the resected tumor was composed mainly of solid nests of atypical argyrophilic cells, and partially of an area of well differentiated tubular adenocarcinoma, showing mutual transition in the mucosal layer. Both immunohistochemical and ultrastructural analyses confirmed the difference in character of tumor cells between these two areas: neuroendocrine cell carcinoma and tubular adenocarcinoma of common type in the intestine. To the best of our knowledge, this is only the third case reported to be a coexisting malignant carcinoid tumor and adenocarcinoma arising in the periampullary region. 相似文献
84.
Aims/hypothesis Type 2 diabetes is characterised by excessive hepatic glucose production and frequently leads to systemic vascular complications. We therefore analysed the relationship between the gene expression profile in the liver and the pathophysiology of Type 2 diabetes.Methods Liver biopsy samples were obtained from twelve patients with Type 2 diabetes and from nine non-diabetic patients. To assay gene expression globally in the livers of both groups, we made complementary DNA (cDNA) microarrays consisting of 1080 human cDNAs. Relative expression ratios of individual genes were obtained by comparing cyanine 5-labelled cDNA from the patients with cyanine 3-labelled cDNA from reference RNA from the liver of a non-diabetic patient.Results On assessing the similarities of differentially expressed genes, the gene expression profiles of the twelve diabetic patients formed a separate cluster from those of the non-diabetic patients. Of the 1080 genes assayed, 105 (9.7%) were up-regulated and 134 (12%) were down-regulated in the diabetic livers (p<0.005). The genes up-regulated in the diabetic patients included those encoding angiogenic factors such as vascular endothelial growth factor, endothelin and platelet-derived growth factor. They also included TGF superfamily genes such as TGFA and TGFB1 as well as bone morphogenetic proteins. Among the down-regulated genes in the diabetic patients were molecules defending against stress, e.g. flavin-containing monooxygenase and superoxide dismutase.Conclusions/interpretation These findings suggest that livers of patients with Type 2 diabetes have gene expression profiles indicative of an increased risk of systemic vascular complications.Electronic Supplementary Material Supplementary material is available in the online version of this article at Abbreviations aRNA
antisense RNA
- BMP
bone morphogenetic protein
- cDNA
complementary DNA
- Cy
cyanine
- FMO
flavin-containing monooxygenase
- NASH
non-alcoholic steatohepatitis
- PDGF
platelet-derived growth factor
- SSC
standard saline citrate
- SOD
superoxide dismutase
- VCAM
vascular cell adhesion molecule
- VEGF
vascular endothelial growth factor 相似文献
85.
Taka-Aki Matsuyama Shin Inoue Kaoru Tanno Mutsuki Makino Genyo Ogawa Tetsuo Sakai Youichi Kobayashi Takashi Katagiri Hidekazu Ota 《Europace : European pacing, arrhythmias, and cardiac electrophysiology》2006,8(11):977-979
We report a case, which we believe to be rare, of adenosine-sensitive atrial tachycardia (AT) originating from the mitral valve annulus. The patient, a 73-year-old woman, died of unrelated cause 4 years after radiofrequency (RF) ablation therapy. Histologically, fibrous replacement of atrial musculature by mature collagenous tissue produced by the RF current was observed at the left inferior atrioventricular junction. In serial sections that included the coronary sinus, two distinct nodal structures containing small, pale myocytes within the fibrous tissue matrix were identified around the region of the ablation lesion. Our case appears to be a unique representation of tissue that was associated with the occurrence and maintenance of AT. 相似文献
86.
Takeda K Cretney E Hayakawa Y Ota T Akiba H Ogasawara K Yagita H Kinoshita K Okumura K Smyth MJ 《Blood》2005,105(5):2082-2089
Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a key effector molecule expressed by natural killer (NK) cells and has been shown to prevent tumor initiation, growth, and metastasis. Here we demonstrate that TRAIL is the dominant cytotoxic effector molecule expressed by NK cells in fetal mice. On birth and with age, NK cells develop full functional capacity, including the ability to secrete interferon gamma (IFN-gamma) and interleukin 13 (IL-13) and mediate perforin- and Fas ligand-mediated cytotoxicity. However, interestingly, a phenotypically immature TRAIL+ NK cell subpopulation is retained in the liver of adult mice, and its retention is dependent on IFN-gamma but not dependent on host IL-12, IL-18, or endogenous host pathogens. Adoptive transfer of either adult liver or neonatal TRAIL+ NK cells resulted in the appearance of TRAIL- NK cells with a mature phenotype, suggesting that these TRAIL+ NK cells were indeed a precursor. Although inducers of IFN-gamma stimulated TRAIL expression on mature NK cells, our data indicated that constitutive TRAIL expression was a hallmark of immature cytotoxic NK cells. This study is the first to describe the concomitant maturation of NK cell effector function with surface phenotype in vivo and implies an important defense role for NK cell TRAIL in the developing immune system. 相似文献
87.
Although Helicobacter pylori have been identified in the liver, the role of Helicobacter sp. in human liver diseases remains unclear. This study explored whether H. pylori were internalized and could persist in hepatocytes. The majority of an inoculum of H. pylori (1 x 10(7) colony forming units) adhered to hepatocytes. Using the gentamicin invasion assay we found that approximately 2% were internalized and persisted following passage for more than 2 months. Electron microscopy confirmed the presence of intracellular Helicobacter. The number of adherent or internalized H. pylori was significantly greater with hepatocytes than with gastric epithelial cells (P < 0.05) and was also dependent on cag pathogenicity island (PAI), VacA, OipA, or BabA status. Transmission electron microscopy was used to confirm adherence and invasion of H. pylori into hepatocytes. Internalization of H. pylori was inhibited by antibodies to beta1-integrin receptors, genistein, and cytochalasin D (P < 0.05) consistent with beta1-integrin acting as a surface receptor with additional requirements for tyrosine kinase phosphorylation and actin polymerization. In summary, H. pylori both adhered to and invaded into hepatocytes in vitro, depending on the virulent factors, and persisted within hepatocytes during subcultures. beta1-integrin is likely a receptor involved in internalization of H. pylori into hepatocytes. 相似文献
88.
Laparoscopic surgery with urinary tract reconstruction and bowel endometriosis resection for deep infiltrating endometriosis
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Deep infiltrating endometriosis (DIE) is the most severe form of endometriosis. It causes chronic pelvic pain, severe dysmenorrhea, deep dyspareunia, dyschezia, and dysuria, markedly impairing the quality of life of women of reproductive age. A number of randomized controlled trials on surgical and medical treatments to reduce the pain associated with endometriosis have been reported, but few have focused on this in DIE. DIE causes not only pain but also functional invasion to the urinary organs and bowel, such as hydronephrosis and bowel stenosis. In addition to DIE resection, surgical treatment involves adhesion separation as well as resection and reconstruction of the urinary organs and bowel; high‐level skills are required. The severity of DIE should be evaluated preoperatively as accurately as possible. Using ENZIAN in conjunction with the AFS (The revised American Fertility Society classification of endometriosis) classification makes a more detailed assessment of DIE possible. The operative procedures used for laparoscopic resection of urinary DIE and reconstruction of the urinary organs are chosen based on the type of lesion (intrinsic/extrinsic) and length of stenosis. In addition to ureteroneocystostomy, the psoas bladder hitch and Boari bladder flap procedures are applied when necessary to extend the urinary tract. Bowel resection for bowel endometriosis is classified into classic segmental resection and conservative approaches (shaving/discoid). When these procedures are employed, it is advisable to work in consultation with urologists and gastroenterologists and to inform the patients of the associated risks and outcomes. Furthermore, postoperative medication is essential because it is difficult to conduct repeated surgeries. 相似文献
89.
Satoshi Kutsuna Yasuyuki Kato Meng Ling Moi Akira Kotaki Masayuki Ota Koh Shinohara Tetsuro Kobayashi Kei Yamamoto Yoshihiro Fujiya Momoko Mawatari Tastuya Sato Junwa Kunimatsu Nozomi Takeshita Kayoko Hayakawa Shuzo Kanagawa Tomohiko Takasaki Norio Ohmagari 《Emerging infectious diseases》2015,21(3):517-520
After 70 years with no confirmed autochthonous cases of dengue fever in Japan, 19 cases were reported during August–September 2014. Dengue virus serotype 1 was detected in 18 patients. Phylogenetic analysis of the envelope protein genome sequence from 3 patients revealed 100% identity with the strain from the first patient (2014) in Japan. 相似文献
90.
Toshihiro Morita Naoki Teratani Harutaka Inoue Yuji Ota 《Internal medicine (Tokyo, Japan)》2021,60(6):847
A 72-year-old women was referred to our hospital because of lower left abdominal pain. Computed tomography showed prominent sigmoid colon dilation and double tumors on both the oral and anal sides. Surgical resection revealed an expanded sigmoid colon involved in double cancer that showed strong adhesion to the surrounding tissues. The pathological findings revealed obstructive colitis and minor perforation in the dilated colon. The minor perforation was considered to have been caused by fecal impaction in the closed cavity between the two tumors, resulting in an increase in colon pressure. 相似文献