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71.
Yasuni Nakanuma Goroku Ohta Haruo Takeshita Yoshikiyo Yamazaki Kenji Doishita Masaru Shimizu 《Pathology international》1983,33(6):1095-1104
Intrahepatic biliary tree with either florid duct lesions or a moderate to severe degree of the duct loss in four livers with chronic hepatic diseases other than primary biliary cirrhosis were studied with histometric and serial section observations. Florid duct lesions, distributed segmentally in the liver, were found in one case with incomplete septal cirrhosis and one case with idiopathic portal hypertension. The florid duct lesions including marked plasma cell infiltration and occasional periductal granulomas, were not associated with any bile duct loss in the two cases. The duct lesions were reversible in one case during a long clinical course. On the other hand, a moderate to severe bile duct loss with biliary epithelial degeneration and necrosis was associated with no or little periductal inflammatory cell infiltration in one other case with chronic intrahepatic cholestasis, probably drug-induced, and in one case with idiopathic portal hypertension. Although florid duct lesions and bile duct loss were important diagnostic features of primary biliary cirrhosis, one of them was observed to develop independently in severely diseased livers, not consistent with a diagnosis of primary biliary cirrhosis, sclerosing cholangitis or intrahepatic bile duct paucity syndrome. 相似文献
72.
Antigenic characteristics and serological identification of 10 black-pigmented Bacteroides species. 总被引:1,自引:0,他引:1 下载免费PDF全文
Strains of 10 black-pigmented Bacteroides species were serologically characterized using absorbed and unabsorbed rabbit antisera. An agglutination test using intact cells or heated cells (100 degrees C for 60 min) from each species and unabsorbed antisera revealed only homologous reactions with little or no reactivity in heterologous assays. Immunodiffusion tests using sonicated antigen demonstrated that Bacteroides gingivalis, B. endodontalis, B. asaccharolyticus, B. macacae, and B. levii are antigenically distinct. Strains of B. gingivalis, B. endodontalis, and B. asaccharolyticus were also clearly identified by the indirect immunofluorescent antibody method. B. intermedius, B. corporis, B. loescheii, B. melaninogenicus, and B. denticola possessed common antigens; however, species-specific antigens detectable with immunoabsorbed antisera were also demonstrated. B. intermedius strains isolated from the human oral cavity included at least two serogroups. In each black-pigmented Bacteroides species, lipopolysaccharide constituted one of the species-specific antigens. 相似文献
73.
Fu J Hato M Ohmae H Matsuoka H Kawabata M Tanabe K Miyamoto Y Leafasia JL Chinzei Y Ohta N 《Parasitology research》2000,86(5):345-351
We analyzed the relationships between levels of antibody specific for merozoite surface glycoprotein-1 (MSP1) of Plasmodium falciparum and clinical manifestations in humans. We prepared recombinant MSP1 proteins representing block 3 (M3), block 6 (M6), blocks
1–6 (M1/6), and block 17. When we divided the slide-positive individuals in Guadalcanal into symptomatic and asymptomatic
groups, the former group showed lower IgG levels against M6 and block 17, but not against M3, than did the asymptomatic group
(P < 0.01). The possibility of nonspecific suppression was unlikely, given that the levels of antibody against poliomyelitis
virus observed in the two groups were almost the same. Among the IgG subclasses tested, production of cytophilic IgG3 seemed to be dominant. When we analyzed epitopes recognized by antibodies against block 17, a peptide (SSSNFLGIS) was preferentially
recognized by sera from asymptomatic individuals. These results suggest that clinical symptoms occurring during falciparum
malaria seem to be associated with the development of levels of antibody against particular epitopes on MSP1, which is under
the control of an immunoregulatory mechanism.
Received: 1 October 1999 / Accepted: 21 October 1999 相似文献
74.
Terada T Matsunaga Y Maeta H Endo K Horie S Ohta T 《Virchows Archiv : an international journal of pathology》1999,435(6):606-611
We report an autopsy case of mixed ductal-endocrine carcinoma of the pancreas presenting as gastrinoma with Zollinger-Ellison
syndrome. A 38-year-old Japanese male was found to have Zollinger-Ellison syndrome and pancreatic gastrinoma, and gastrectomy
and resection of the pancreatic tumor were performed. However, hypergastrinemia persisted, and the patient died of disseminated
carcinomatosis at 62 years of age, 24 years after the onset of Zollinger-Ellison syndrome. At autopsy, the main tumor was
present in the residual pancreas, and metastases were noted in many organs. In the pancreas and other organs, ductal and endocrine
carcinoma areas were mixed and there was a gradual transition between the two. No acinar differentiation was noted. The ductal
elements were positive for mucins and carcinoembryonic antigen but negative for neuroendocrine markers, while endocrine elements
were positive for chromogranin A and synaptophysin and to a lesser extent for gastrin, but negative for mucins and carcinoembryonic
antigen. The ductal elements comprised about 30% of the tumor cells, and endocrine elements 70%. According to the revised
World Health Organization classification, our case was diagnosed as mixed ductal-endocrine carcinoma. Our case is rare because
the tumor manifested as gastrinoma with Zollinger-Ellison syndrome and the patient survived for 24 years. To the best of our
knowledge, no such case has been reported. Our case suggests that pancreatic endocrine tumors may evolve into mixed ductal-endocrine
carcinomas.
Received: 14 April 1999 / Accepted: 7 July 1999 相似文献
75.
Kazuhiro Tsukamoto Nobutaka Ohta Yasumasa Shirai M. Emi 《Journal of human genetics》1998,43(4):278-279
Tumor necrosis factor alpha (TNFα) in activated monocytes exerts cytotoxic activity and has a variety of other biological
effects. We isolated a polymorphic dinucleotide (CA) repeat sequence from a genomic clone containing the gene located at 6p21.3.
High heterozygosity (0.80) makes this polymorphism a useful marker in the genetic study of disorders affecting immunological
response and cell differentiation.
Received: June 2, 1998 / Accepted: June 24, 1998 相似文献
76.
Treatment of persistent sleep-wake schedule disorders in adolescents with methylcobalamin (vitamin B12). 总被引:1,自引:2,他引:1
Two adolescent patients suffering from persistent sleep-wake schedule disorders appear to have responded to treatment with vitamin B12 (methylcobalamin). A 15-year-old girl with delayed sleep phase syndrome (DSPS) and a 17-year-old boy with hypernychthemeral syndrome complained of not being able to attend school despite many trials of medication. The improvement of the sleep-wake rhythm disorders appeared immediately after the administration of high doses (3,000 micrograms/day) of methylcobalamin. Neither patient showed any laboratory or clinical evidence of vitamin B12 deficiency or hypothyroidism (which can cause B12 deficiency). Serum concentrations of vitamin B12 during treatment were in the high range of normal or above normal. The duration of the sleep period of the DSPS patient decreased gradually from 10 hours to 7 hours, and the time of sleep onset advanced from 2 a.m. to midnight. The period of the sleep-wake cycle of the hypernychthemeral patient was 24.6 hours before treatment and 24.0 hours after treatment. The relationship between the circadian basis of these disorders and vitamin B12 and its metabolites is discussed. 相似文献
77.
Y Ohta K Shimamura N Lertprasertsuke M Horiuchi R Y Osamura 《Acta pathologica japonica》1989,39(7):446-450
An autopsy case of malignant midline reticulosis (MMR) is reported. The patient, a 42-year-old Japanese male, died after a clinical course of 22 months. Autopsy revealed extensive infiltration of generalized organs by the tumor cells, suggesting that the disease was highly malignant in nature. Staining with monoclonal antibodies against T-cell surface antigens Leu 4 on frozen sections and UCHL1 on paraffin-embedded sections enabled us to examine the phenotype of the tumor cells with good morphological preservation and to verify the T cell nature of the tumor. 相似文献
78.
BACKGROUND: In Asian countries, there is no epidemiological report on seasonal affective disorder (SAD) in different age groups and different geographic regions surveyed at the same time. The aim of this study was to estimate the prevalence rates of SAD and risk factors for SAD in adults and high-school students, with special reference to the difference of winter SAD between northern and southern regions in Japan. METHODS: A total of 3237 high-school students and 4858 workers living in Japan (31.3-43.5 degrees N) responded to this epidemiological survey using Japanese version of the Seasonal Pattern Assessment Questionnaire (SPAQ). RESULTS: The overall prevalence rates of winter SAD (subsyndromal winter SAD) and summer SAD (subsyndromal summer SAD) in high-school students were 0.91(2.21) and 0.81(2.57)%, respectively. In workers, these rates were 0.45(1.16) and 0.43(0.71)%, respectively. Although no regional difference was noted in high-school students with winter seasonal type, the estimated odds ratio of this type for northern workers was nearly 3-fold higher than the southern counterparts. The prevalence rates of each seasonal type were not significantly different between two sexes in both age groups. No clear dependence on latitude was seen with regard to summer SAD in both age groups. LIMITATIONS: The effect of climate on SAD could not be entirely excluded from geophysical factor as indexed by latitude. CONCLUSIONS: SAD was less common in adults than in high-school students. While latitude was a major determinant of winter type in adults, socio-cultural factors or other contributing factors might affect the development of this type in high-school students. 相似文献
79.
80.
Tadao Tanimoto Shigeto Yamamoto Madoka Taniai Mutsuko Taniguchi Harumi Ariyasu Chie Ushio Miho Aga Yohei Mukai Yasuo Tsutsumi Toshio Ariyasu Tsunetaka Ohta Shigeharu Fukuda 《Journal of interferon & cytokine research》2007,27(6):517-523
Although there are at least 13 interferon-alpha (IFN-alpha) subtypes in humans, interactions between the subtypes remain unknown. To understand IFN-alpha interactions, we examined the antiproliferative activities and the receptor binding affinities of different combinations of IFN-alpha2 and IFN-alpha8 using six renal cell carcinoma (RCC) cell lines. Although IFN-alpha8 was the more potent subtype, synergistic and antagonistic antiproliferative effects were also observed in certain combinations of IFN-alpha2 and IFN-alpha8. To analyze the interactions between IFN-alpha2 and IFN-alpha8, the receptor-binding kinetics of different combinations of IFN-alpha2 and IFN- alpha8 to the IFN-alpha receptors, IFNAR-1 or IFNAR-2, were measured using a surface plasmon resonance-based biosensor. Unexpectedly, the receptor binding kinetics to IFNAR-2 but not to IFNAR-1 were mutually related to antiproliferative activity and increase in the binding speed (K(a)) for IFNAR-2. Moreover, we observed the increased fluorescence intensity (FI) of biotin-labeled IFN-alpha8 to IFNAR-2 by receptor binding inhibition assay with unlabeled IFN-alpha2 but not the other combinations. These findings indicate that the binding manner of IFN-alpha8 for IFNAR-2 is different from that of IFN-alpha2, suggesting that binding of IFN-alpha8 rather than binding of IFN-alpha2 to IFNAR-2 leads to activation and subsequent antiproliferative activity despite the same antiviral activity in RCC. 相似文献