首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1397篇
  免费   61篇
  国内免费   4篇
耳鼻咽喉   23篇
儿科学   23篇
妇产科学   27篇
基础医学   200篇
口腔科学   3篇
临床医学   94篇
内科学   417篇
皮肤病学   9篇
神经病学   119篇
特种医学   66篇
外科学   140篇
综合类   11篇
预防医学   61篇
眼科学   4篇
药学   151篇
中国医学   3篇
肿瘤学   111篇
  2023年   15篇
  2022年   44篇
  2021年   72篇
  2020年   25篇
  2019年   33篇
  2018年   35篇
  2017年   30篇
  2016年   33篇
  2015年   40篇
  2014年   58篇
  2013年   67篇
  2012年   126篇
  2011年   129篇
  2010年   52篇
  2009年   43篇
  2008年   86篇
  2007年   82篇
  2006年   70篇
  2005年   89篇
  2004年   66篇
  2003年   69篇
  2002年   43篇
  2001年   14篇
  2000年   13篇
  1999年   19篇
  1998年   13篇
  1997年   9篇
  1996年   8篇
  1995年   3篇
  1993年   4篇
  1992年   5篇
  1990年   4篇
  1989年   3篇
  1987年   5篇
  1986年   4篇
  1985年   2篇
  1983年   6篇
  1982年   4篇
  1981年   2篇
  1979年   2篇
  1978年   3篇
  1977年   5篇
  1976年   2篇
  1975年   7篇
  1974年   2篇
  1973年   3篇
  1971年   3篇
  1966年   1篇
  1965年   1篇
  1937年   1篇
排序方式: 共有1462条查询结果,搜索用时 46 毫秒
11.
Errata     
The online version of the original article can be found at  相似文献   
12.
The origin of testicular germ cell tumours occurring during childhood is poorly understood. In adults, the classical seminomas and non-seminomas originate from carcinoma in situ of the testis, which can usually also be detected in seminiferous tubules adjacent to the tumours. In order to contribute with information regarding a possible association between carcinoma in situ and the childhood group of germ cell tumours, we investigated seminiferous tubules adjacent to 13 infantile yolk sac tumours, five infantile teratomas, and six adolescent germ cell tumours of various types, using morphological evaluation, immunohistochemical staining with markers for carcinoma in situ cells, and densitometric DNA measurement of the germ cells. We detected clear differences between the germ cell populations adjacent to adolescent and infantile germ cell tumours. The former were associated with both normal germ cells and carcinoma in situ cells. The presence of carcinoma in situ cells strongly suggested that the adolescent tumours arose from carcinoma in situ cells, like germ cell tumours occurring in adult men. Although we were in doubt in two cases, the infantile germ cell tumours were in general not associated with carcinoma in situ cells. The aetiology of infantile yolk sac tumours and teratomas may therefore be fundamentally different from that of adolescent and adult germ cell tumours. The origin of yolk sac tumours and teratomas remains to be elucidated.  相似文献   
13.
Of 33 consecutive patients with chronic myelocytic leukemia, examined during metamorphosis, 82% showed chromosome abnormalities in addition to the Ph1. Aberrations most frequently encountered were +8 (39%), +22q - (30%), and i(17q) (18%). Translocations other than the Ph1 were observed in four cases and - Y clones in four cases. Discrepancies in the cytogenetic pattern between bone marrow and extramedullary tissues or blood were noted in a total of 15 patients. In six cases, transformation occurred in extramedullary organs at a time when it was not present in the marrow. In three cases the bone marrow transformation was preceded by a lymph node blastic infiltrate; in one case, by a skin infiltrate; and in one case, by a subdural blastoma. Clonal abnormalities additional to the Ph1 were identified in the tumor tissue from all these cases. Patients with primary extramedullary transformation tended to have a lower median age at onset of metamorphosis, shorter survival, and higher incidence of chromosome abnormalities than the cases without extramedullary involvement. Patients with only Ph1-positive cells and no other anomalies had a slightly longer duration of metamorphosis and longer total survival. Basophilia and thrombocytopenia were more marked in cases with i(17q) than in the rest of the series.  相似文献   
14.
15.
Many unbalanced large copy number variants reviewed in the paper are associated with syndromic orofacial clefts, including a 1.6 Mb deletion on chromosome 3q29. The current report presents a new family with this recurrent deletion identified via whole-exome sequencing and confirmed by array comparative genomic hybridization. The proband exhibited a more severe clinical phenotype than his affected mother, comprising right-sided cleft lip/alveolus and cleft palate, advanced dental caries, heart defect, hypospadias, psychomotor, and speech delay, and an intellectual disability. Data analysis from the 3q29 registry revealed that the 3q29 deletion increases the risk of clefting by nearly 30-fold. No additional rare and pathogenic nucleotide variants were identified that could explain the clefting phenotype and observed intrafamilial phenotypic heterogeneity. These data suggest that the 3q29 deletion may be the primary risk factor for clefting, with additional genomic variants located outside the coding sequences, methylation changes, or environmental exposure serving as modifiers of this risk. Additional studies, including whole-genome sequencing or methylation analyses, should be performed to identify genetic factors underlying the phenotypic variation associated with the recurrent 3q29 deletion.  相似文献   
16.
Background: To determine the maximum tolerable dose (MTD) and therapeutic activity of MTHF-modulated FU using two different administration schedules of the antimetabolite (bolus vs. two-hour infusion), the present randomized study using a 'pick-the-winner' design was undertaken in patients with advanced colorectal cancer.Patients and methods: Eighty-two patients with previously untreated advanced measurable colorectal cancer were randomly assigned to treatment with MTHF (100 mg/m2 days 1–5 i.v. bolus) plus FU (400 mg/m2 days 1–5) given either as i.v. bolus injection or as a two-hour infusion every four weeks. In the absence of dose-limiting toxicity (DLT, defined as WHO grade 3 hematotoxicity and/or WHO grade 2 nonhematologic side effects) and evidence of progressive disease, the FU dose was escalated by 50 mg/m2/day during each subsequent cycle until the individual maximum tolerable dose (MTD) was reached.Results: Forty patients were randomized to the FU bolus arm and 42 patients to the FU two-hour infusion arm. The median MTD was 475 mg/m2/day (95% CI: 450–500) in the FU bolus arm with stomatitis ± diarrhea being the most common DLT. Gastrointestinal side effects were also dose-limiting in the two-hour infusion arm; however, the median MTD was 600 mg/m2/day (95% CI: 568–632). Myelosuppression was more pronounced in the FU bolus arm than in the two-hour infusion arm. The overall response rates were 27.5% (95% CI: 15–44%; 1 CR and 10 PR) for patients treated in the bolus arm and 14.5% (95% CI: 5–28%; 1 CR and 5 PR) for those treated in the two-hour infusion arm. Analogous to recorded response, median time to progression (8.5 vs. 6.25) and overall survival time (14.0 vs. 11.0) tended to be superior in the FU bolus arm.Conclusions: The observed differences in tolerable drug dose and toxicity between the two treatment arms might be explained by the administration schedule-dependent clinical pharmacokinetics of FU and/or the difference in extent of biochemical modulation of the antimetabolite through MTHF. The fact that the two regimens were not equitoxic probably also helps to explain the favourable response activity noted in the MTHF/FU bolus arm. Whether MTHF is as effective as leucovorin for biochemical modulation of FU remains to be determined in a randomized trial, for which we would recommend its combined use with bolus FU ('winner arm') using a starting dose of 400 mg/m2/day ×5.  相似文献   
17.
18.
PURPOSE: Various chemotherapeutic regimens have been applied for treatment of mucosa-associated lymphoid tissue (MALT) lymphoma, but no standard regimen has been identified to date. In view of the activity of oxaliplatin (L-OHP) in various types of lymphoma, we performed a phase II study to evaluate the activity of L-OHP for treatment of MALT lymphoma. The primary objective of this study was to determine the objective response rate according to WHO standard criteria. PATIENTS AND METHODS: A total of 16 patients with MALT lymphoma of various sites of origin (four of the ocular adnexa, five of the salivary glands, three of the stomach, two of the lung, and one of the colon and the breast) were administered L-OHP at a dose of 130 mg/m2 infused during 2 hours every 3 weeks. Restaging was performed every two cycles; treatment was continued until complete remission (CR) or for a maximum of six cycles in responders. RESULTS: Sixty-five cycles were administered (median, four; range, two to six); toxicity consisted of transient sensory neuropathy in eight patients and nausea/emesis WHO grade 2 in two patients, whereas hematologic adverse effects (thrombocytopenia and leukocytopenia grade 2) occurred in only one patient each. Fifteen patients responded to chemotherapy, with nine achieving CR (56%), six (37.5%) achieving partial response, and one achieving stable disease; the median time to response was 4 months (range; 2 to 4 months). CONCLUSION: These data suggest L-OHP is a highly active agent for treatment of MALT lymphoma. However, a longer follow-up is needed to judge whether these remissions are durable.  相似文献   
19.
20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号