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p53 mutations in non-small cell lung cancer in Japan: association between mutations and smoking. 总被引:20,自引:0,他引:20
H Suzuki T Takahashi T Kuroishi M Suyama Y Ariyoshi T Takahashi R Ueda 《Cancer research》1992,52(3):734-736
The p53 gene has been implicated as a tumor suppressor gene involved in the pathogenesis of lung cancer. Our previous study revealed that the p53 gene is frequently mutated with a distinct nucleotide substitution pattern in small cell lung cancer specimens in Japanese patients. In this study, we examined 30 primary, resected non-small cell lung cancer samples in Japanese patients using complementary DNA-polymerase chain reaction and sequencing. Mutations changing the p53 coding sequence were found in 14 of 30 tumor samples (47%), while G:C to T:A transversions which are uncommon in other cancers such as colon cancer were the most frequently observed mutations, in agreement with an earlier report on non-small cell lung cancer in American patients. Furthermore, the present study shows for the first time that in univariate and multivariate analyses, the presence of p53 mutations is closely associated with lifetime cigarette consumption. 相似文献
3.
HTX rat, a congenital hydrocephalic strain, develops ventricular dilatation and cystic cavities in the cerebral white matter after birth. To investigate the reactive changes in glial cells around these cavities, immunohistochemical staining for glial fibrillary acidic protein (GFAP), a specific marker protein of astrocytes, and bromodeoxyuridine (BrdU), a thymidine analogue, was carried out on 107 Wistar and HTX rat brains from birth to postnatal day (P) 26. Animals were divided into three groups: Group A, Wistar rats as normal controls; Group B, HTX rats with a normal structure or only mild ventricular dilatation without any lesion in the white matter; and Group C, HTX rats with severe ventricular dilatation and cyst formation in the white matter. Group B rats showed similar development of GFAP-positive (GFAP+) cells to that in Group A rats, both morphologically and quantitatively. On the other hand, Group C rats showed definite structural changes in GFAP+ cells around the cystic cavities from P5. These included enriched cytoplasm and thickened cell processes with increased GFAP expression, and enveloped most cyst walls from P10. However, quantitative examination of the percentage of GFAP+ cells in Group C rats showed a similar developmental profile to those in Group A and B rats. Furthermore, the labeling index of BrdU-positive cells, indicating S-phase cells, in the white matter in Group C rats showed a similar decreasing pattern to that in Group A and B rats from P1 to P26.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
4.
Twenty-two twins' families were investigated to determine the influence of a genetic factor in the etiology of allergic diseases in children. Zygosity was confirmed by eight red cell blood types and HLA type. Eight pairs of monozygotic twins were divided by a probability of monozygosity as calculated from Essen-M?ller's method. Concordance rate of allergic disease and asthma were 88% in MZ, 86% in DZ, 75%, 73% and that of positive rate of DF-specific IgE antibody were 60% in MZ, 58% in DZ. In DZ, not sharing the same HLA haplotypes, concordance of the positive rate of DF-specific IgE antibody was 0%. Concomitant coefficiency of total serum IgE levels were 0.593 in MZ, 0.063 in DZ. These data suggested that IgE production may be influenced by genetic factors. 相似文献
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Y Iikura M Baba H Mikawa S Nishima K Maeda T Akasaka T Masaki M Arita H Niiya N Koya 《Arerugī》1991,40(2):132-140
Many asthmatic children have experienced atopic dermatitis in their younger days. As it is very difficult to cure childhood asthma we attempted to determine the anti-allergic drug effects in preventing the development of asthma by using ketotifen on atopic dermatitis patients. The study was designed as a placebo controlled double blind trial of 128 atopic dermatitis patients aged from 2-34 months. 91 patients were given complete analysis in the study, 33 patients were given only a safety rate and 4 patients were dropped. The 91 patients were followed for 52 weeks. Our primary finding was that the development of bronchial asthma was inhibited in the ketotifen group compared to the placebo controlled group with a statistically significant degree (p less than 0.001). We also found that clinical symptoms of atopic dermatitis were significantly improved in the ketotifen group (p less than 0.001). Only 5 patients complained of mild side effects. 相似文献
7.
Kazuhito Yamamoto Hirotaka Osada Masao Seto Michinori Ogura Hisamitsu Suzuki Kazuhiko R. Utsumi Atsushi Oyama Yutaka Ariyoshi Shigeo Nakamura Souji Kurita Toshitada Takahashi Ryuzo Ueda 《Cancer science》1992,83(5):465-476
A case of non-Hodgkin's lymphoma showed a phenotypic and genotypic cell lineage switch twice during nine years of his clinical history; first, T-cell type, pleomorphic small cell lymphoma developed, followed by B-cell type, diffuse centroblastic/centrocytic lymphoma, and finally T-zone lymphoma without follicles again developed, from which AST-1 cultured cell line was established. Karyotype analysis demonstrated a shared abnormal chromosome, der(1)t(1;?)(p36;?), among the first relapsed B-cell tumor, the second relapsed T-cell tumor and AST-1 cell line. Furthermore, T-cell receptor (TCR) γ gene rearrangement bands of the same size were observed in the first relapsed B-cell tumor and the second relapsed T-cell tumor as well as AST-1 cell line. These results suggested that both relapsed tumors of different cell lineages are derived from a common malignant clone, presumably a committed lymphoid stem cell. A unique translocation, t(2;14)(q37;q11.2), which may involve TCR δ/α gene complex, was observed in the second relapsed tumor and AST-1 cells. To attempt to isolate the breakpoint of this translocation, the configuration of TCR δ/α gene complex was studied. The result showed that two rearrangements of TCR α gene detected with Jα probes were the products of the normal TCR rearrangement process, and were not involved in the translocation at this region. This patient, together with the AST-1 cell line, provided us a unique opportunity to study the development and clonal evolution of malignant lymphoma. 相似文献
8.
Twenty-six families with allergic siblings were investigated to define the mode of inheritance of asthma and DF specific IgE antibody production in children. The affected sib pair method was used to establish the linkage between disease susceptibility genes and HLA antigens. The affected sib pair method revealed that in asthmatic families chi 2 = 4.9 (no significance) and in DF-specific IgE positive families chi 2 = 6.2 (p less than 0.05). This study suggests that the gene of DF-specific IgE antibody production is linked to HLA haplotypes, but the mode of inheritance of DF-specific IgE antibody production couldn't be defined. 相似文献
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H Imura T Takahashi T Matsuda O Yoshida H Ohkura Y Seitetsu Y Seino M Ishii M Kuwabara Y Ariyoshi 《Gan to kagaku ryoho. Cancer & chemotherapy》1989,16(6):2195-2202
We describe an immunoradiometric competitive inhibition assay of the serum levels of the 2----6 sialyl Lewisa antigen, using "SLA 2-6 Otsuka" kits. The assay required only duplicate 50-microliters samples, and the concentration of 2----6 sialyl Lewisa antigen in serum was determined by reference to a standard curve ranging from 0 to 160 arbitrary U/ml. The intra- and inter-assays reproducibilities were good and analytical recovery of antigen were excellent. The serum levels of the antigen were highly dependent on the Lewis blood types of the tested individuals; i.e., the levels of the antigen in the sera of the Lewisa-b- individuals were significantly lower than those of the antigen obtained with the Lewisa+b- and Lewisa-b+ individuals. The cut-off value (42 U/ml) was obtained as mean + 2SD, which was carefully calculated from the antigen levels in sera of the non-Lewisa-b- individuals. 相似文献