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排序方式: 共有1208条查询结果,搜索用时 484 毫秒
81.
Yeh YP Luh DL Chang SH Suo J Chang HJ Chen TH 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2005,99(7):509-516
We aimed to assess whether tuberculin reactivity in adults is affected by bacille Calmette-Guerin (BCG) vaccination after 50 years of universal BCG vaccination with 80-95% coverage. A community-based study on tuberculin reactivity in 619 participants was conducted in February 2000 in Keelung city, Taiwan. Information on BCG vaccination policies and annual risk of infection (ARI) in the underlying population was extracted from consecutive national prevalence surveys relating to the period 1952-1997. Compared with the expected ARI estimate, the standardized morbidity ratio of positive tuberculin response for vaccination in infancy was 2.2 (95% CI 0.3-15.5) for those aged <10 years. The corresponding figures for older age groups ranged from 3.6 (95% CI 2.2-5.9) for those aged 10-12 years to 0.7 (95% CI 0.5-0.9) for those aged 57-67 years. This suggests that the effect of BCG vaccination on positive tuberculin response in adults aged >30 years is probably negligible irrespective of age at vaccination or revaccination and that the tuberculin skin test can be used to diagnose TB in control programmes in countries with moderate or high incidence of TB. 相似文献
82.
PURPOSE: The incidence of tuberculosis (TB) in Taiwan is known to be high in aboriginal mountain areas and low in the surrounding non-mountain areas. The aim of this study was to assess whether TB incident cases in the surroundings of mountain areas decreased with distance from foci of mountain areas. METHODS: The mountain areas in Taiwan are adjacent to each other and divided into four geographic groups. Townships with high TB incidence in each group were treated as the foci of TB infection. The surrounding townships were then classified, by distance away from foci, into three levels: < 20 km, 20 to 40 km, and 40 to 60 km. Data were obtained on a total of 84,366 TB cases from 1991 to 1997 from the Taiwan Tuberculous Disease Registry Center. RESULTS: The incidence of TB in each of the four groups was significantly higher in the mountain areas compared with non-mountain areas, with relative risks ranging from 8.4 (95% confidence interval [CI], 7.8-9.1) for the southern group to 15.0 (95% CI, 13.4-16.9) for the northern group. Relative risks for surrounding townships decreased with distance in all four groups. Such a gradient relationship was statistically significant. CONCLUSIONS: A significant dose-response relationship between distance from townships with a high incidence of TB and the incidence of TB in the surrounding areas has been demonstrated. 相似文献
83.
Qi X Wang X Wang L Wang Q Cheng S Suo J Chang J 《European journal of medicinal chemistry》2005,40(8):805-810
Since the discovery of 2,2'-dimethoxycarbonyl-4,4-dimethoxy-5,6,5',6'-biomethylenedioxy-biphenyl (DDB) as a potent anti-HBV agent, we have studied the structure-activity relationships of 4,4'-dimethoxy-5,6,5',6'-dimethenedioxy-2-alkyloxycarbonyl-2'-(4-substituted benzyl piperazin-1-yl)carbonyl-biphenyl as anti-HBV agents. Therefore, it is rational to extend this study to the 3,3'-disustituted-4,4'-dimethoxy-5,6,5',6'-dimethenedioxy-2-alkyloxycarbonyl-2'-Serine derivatives. Thus, in an attempt to develop an efficient method for the preparation of a large number of DDB derivatives, the reaction between a DDB acid chloride and serine derivatives on solid support was studied. The structure of resulted compounds was confirmed by LC-MS and (1)H NMR analysis. Compounds 2a, 2d, 2f, 2j showed in vitro anti-HBV activity without significant toxicity up to 100 microM. 相似文献
84.
Citron BA Zoloty JE Suo Z Festoff BW 《Brain research. Molecular brain research》2005,135(1-2):122-133
Tissue transglutaminase (tTG) is a member of a multigene family principally involved in catalyzing the formation of protein cross-links. Unlike other members of the transglutaminase family, tTG is multifunctional since it also serves as a guanosine triphosphate (GTP) binding protein (Galpha(h)) and participates in cell adhesion. Different isoforms of tTG can be produced by proteolysis or alternative splicing. We find that tTG mRNA is expressed at low levels in the mouse CNS relative to other tissues, and at lower levels in the CNS of mouse in comparison to that of human or rat. tTG mRNA levels are higher in the heart compared to the CNS, for example, and much higher in the liver. Within the CNS, tTG message is lowest in the adult cerebellum and thalamus and highest in the frontal cortex and striatum. In the hippocampus, tTG expression is highest during embryonic development and falls off dramatically after 1 week of life. We did not find alternative splicing of the mouse tTG. At the protein level, the predominant isoform is approximately 62 kDa. In summary, tTG, an important factor in neuronal survival, is expressed at low levels in the mouse CNS and, unlike rat and human tTG, does not appear to be regulated by alternative splicing. These findings have implications for analyses of rodent tTG expression in human neurodegenerative and neurotrauma models where alternative processing may be an attractive pathogenetic mechanism. They further impact on drug discovery paradigms, where modulation of activity may have therapeutic value. 相似文献
85.
Suo Z Risberg B Karlsson MG Villman K Skovlund E Nesland JM 《International journal of surgical pathology》2002,10(2):91-99
Expression of EGF, HB-EGF, TGF-alpha, HRG-alpha, HRG-beta1, and HRG-beta3 in 100 frozen breast carcinoma materials was immunohistochemically studied. Among these tumors, 67% were positive for EGF, 53% for HB-EGF, 57% for TGF-alpha, 60% for HRG-alpha, 53% for HRG-beta1, and 63% for HRG-beta3 in the neoplastic epithelial cells. No significant associations between expression of the growth factors and clinicopathological features like tumor size, histologic grade, node status, ploidy, ER status, and c-erbB-4 expression were observed, with the exceptions that significant relations were present between EGF expression and tumor size (p = 0.01) and between HRG-beta3 expression and node status (p = 0.02). The expressions of these growth factors showed no association with cancer-specific survival by the Kaplan Meier analysis. 相似文献
86.
One of the most studied onco-gene families in breast tumors is the type 1 protein tyrosine kinase family, which consists of EGFR, c-erbB-2, c-erbB-3, and c-erbB-4. Overexpression of c-erbB-2 protein/mRNA in breast carcinomas is consistently associated with poor prognosis, while EGFR overexpression has been confirmed to have a synergistic clinical effect on the c-erbB-2 influence. The expression pattern of c-erbB-4 in breast carcinomas is special. Unlike other type 1 protein tyrosine kinases, expression of c-erbB-4 protein/mRNA is reduced in carcinomas compared with that in normal breast epithelia, and its expression has also been associated with a better clinical outcome, indicating the need for c-erbB-4 analysis when clinical therapeutic application of EGFR and c-erbB-2 anitbodies is considered. In addition, studies of the adaptor proteins in breast carcinomas are highly indicated in order to clarify the mechanisms behind the dysregulated expression of such receptors in breast carcinomas. 相似文献
87.
88.
体外模拟二氧化碳人工气腹对宫颈癌细胞生长的影响 总被引:1,自引:0,他引:1
目的 观察二氧化碳(CO2)人工气腹对宫颈癌细胞生长的影响,探讨其与乏氧的关系。方法 2005-10—2006-03华中科技大学同济医学院附属协和医院通过裸鼠右下腹腔注射宫颈癌细胞,注射宫颈癌细胞株(Hela)数量:4×10^9/L:将注射后40只裸鼠随机分成4组,每组10只:阴性对照组(常氧组):仅给予右下腹腔注射宫颈癌细胞;CO2气腹模拟环境按CO2灌注压分3组:CO2灌注压4mmHg(1mmHg=0.133kPa)组,CO2灌注压10mmHg组,CO2灌注压16mmHg组.4周后观察裸鼠体重改变、切除瘤灶称瘤重、瘤体标本用免疫组化测定增殖细胞核抗原(PCNA)、Western-blot方法检测瘤体的缺氧诱导因子-1α(HIF-1α)表达.结果 与阴性对照组比较,CO2气腹各组裸鼠体重下降明显,而瘤体重量增加相对显著,并随着CO2灌注压的增高这种趋势更为显著(P〈0.05);CO2气腹各组裸鼠PCNA表达显著高于阴性对照组(P〈0.01);CO2气腹各组裸鼠HIF-1α蛋白的表达与阴性对照组比较明显增加,差异有统计学意义(P〈0.01).结论 与阴性对照组比较,CO2人工气腹环境可促进宫颈癌细胞生长,其机制可能与HIF-1α激活了PCNA表达,促进了细胞增殖有关。 相似文献
89.
BACKGROUND AND PURPOSE: Hypoxia, a frequent characteristic of cervical cancer, is associated with reduced sensitivity to irradiation and thus may be a source of radiotherapy failure. This study was planned to test the hypothesis, that inhalation of oxygen during radiotherapy may increase the radiation effect on the tumor and improve loco-regional control and overall survival. MATERIAL AND METHODS: From 1963 to 1965, a consecutive series of 208 patients with cervical cancer stage II/III who were to be treated by external irradiation plus radium inserts, were included in this study. They were randomly assigned to either receive oxygen inhalations during the radiotherapy sessions or just breathing air. Due to technical reasons the oxygen group was divided. For the first 10 months, they did receive oxygen during the radium inserts only, the last 13 months during all radiotherapy sessions. RESULTS: After median 33 years follow-up, there are no differences in overall survival, cancer-specific survival or loco-regional control. Subgroup analysis shows significantly improved loco-regional control in the stage IIB patients, with squamous cell carcinoma who received oxygen during all radiotherapy sessions. This improvement was especially pronounced among the patients who also received blood transfusions. CONCLUSIONS: There was no influence of normobaric oxygen treatment on the overall outcome to radiotherapy in patients with stage II cervical cancer, but subgroup analyses support the hypothesis that there is tumor areas of hypoxia-based radioresistance that may be counteracted by oxygen administration. 相似文献
90.
Oncogenic aberrations in the p53 pathway are associated with a high S phase fraction and poor patient survival in B-cell Non-Hodgkin's lymphoma 总被引:7,自引:0,他引:7
Stokke T Galteland E Holte H Smedshammer L Suo Z Smeland EB Børresen-Dale AL DeAngelis P Steen HB 《International journal of cancer. Journal international du cancer》2000,89(4):313-324
The implications of aberrations in the p53 pathway for induction of apoptosis and regulation of S phase entry, and for patient survival, were investigated in 83 B-cell Non-Hodgkin's lymphomas. Eight cases had missense mutations in exons 5, 7, 8 and 9 as revealed by constant denaturant gel electrophoresis and sequencing. Fifteen cases had lost 1 TP53 allele as revealed by fluorescent in situ hybridization and comparative genomic hybridization. Ten cases expressed high levels of p53 as assessed by immunoblotting and immunohistochemistry. S phase fractions were higher, apoptotic fractions were the same and survival times were shorter in all aberration groups compared with the cases with no TP53/p53 aberrations. Since many tumors had more than one TP53/p53 aberration, the tumors were divided into groups with the following characteristics: no TP53/p53 aberrations; loss of one TP53 allele only (9 cases), TP53 point mutation (8 cases), high-level p53 expression and no TP53 mutation (3 cases). Tumors from the 3 latter groups had higher median S phase fractions (5%, 7.6%, and 5%, respectively, p<0.02) than the cases without any aberrations (1.1%), and survival time for these patients was much shorter (relative risks of 5.9, 8.9, and 6.6, respectively, p<0.003). Apoptotic fractions were similar in all these groups (p=0.09). Multivariate analysis showed that the presence of TP53/p53 aberrations is a strong and independent prognostic parameter in B-cell Non-Hodgkin's lymphoma. 相似文献