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   15905篇
  免费   655篇
  国内免费   137篇
耳鼻咽喉   109篇
儿科学   355篇
妇产科学   136篇
基础医学   1886篇
口腔科学   296篇
临床医学   973篇
内科学   4239篇
皮肤病学   265篇
神经病学   1374篇
特种医学   613篇
外科学   2814篇
综合类   67篇
一般理论   1篇
预防医学   372篇
眼科学   212篇
药学   1044篇
中国医学   24篇
肿瘤学   1917篇
  2023年   91篇
  2022年   193篇
  2021年   328篇
  2020年   157篇
  2019年   257篇
  2018年   264篇
  2017年   196篇
  2016年   296篇
  2015年   322篇
  2014年   399篇
  2013年   550篇
  2012年   899篇
  2011年   990篇
  2010年   571篇
  2009年   483篇
  2008年   979篇
  2007年   990篇
  2006年   1024篇
  2005年   1035篇
  2004年   1000篇
  2003年   1005篇
  2002年   1032篇
  2001年   256篇
  2000年   231篇
  1999年   286篇
  1998年   286篇
  1997年   206篇
  1996年   188篇
  1995年   173篇
  1994年   161篇
  1993年   154篇
  1992年   157篇
  1991年   174篇
  1990年   150篇
  1989年   142篇
  1988年   108篇
  1987年   99篇
  1986年   101篇
  1985年   93篇
  1984年   78篇
  1983年   65篇
  1982年   50篇
  1981年   42篇
  1980年   41篇
  1979年   63篇
  1977年   43篇
  1975年   31篇
  1974年   34篇
  1973年   26篇
  1972年   26篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
83.
As a highly regenerative organ, the intestine is a promising source for cellular reprogramming for replacing lost pancreatic β cells in diabetes. Gut enterochromaffin cells can be converted to insulin-producing cells by forkhead box O1 (FoxO1) ablation, but their numbers are limited. In this study, we report that insulin-immunoreactive cells with Paneth/goblet cell features are present in human fetal intestine. Accordingly, lineage-tracing experiments show that, upon genetic or pharmacologic FoxO1 ablation, the Paneth/goblet lineage can also undergo conversion to the insulin lineage. We designed a screening platform in gut organoids to accurately quantitate β-like cell reprogramming and fine-tune a combination treatment to increase the efficiency of the conversion process in mice and human adult intestinal organoids. We identified a triple blockade of FOXO1, Notch, and TGF-β that, when tested in insulin-deficient streptozotocin (STZ) or NOD diabetic animals, resulted in near normalization of glucose levels, associated with the generation of intestinal insulin-producing cells. The findings illustrate a therapeutic approach for replacing insulin treatment in diabetes.  相似文献   
84.
The aim of this literature review was to summarize the clinical characteristics and symptoms of temporomandibular joint diseases, and to discuss the associations between temporomandibular joint diseases and categorization of malocclusion. Electronic literature searches were performed using the PubMed database. The authors established a differential diagnostic method for temporomandibular joint diseases related to malocclusion. A literature search using PubMed yielded 213 texts, of which based on exclusion criteria, 28 were included in this study. Malocclusions were categorized into 5 types. The authors suggested a diagnostic tree of temporomandibular joint diseases based on the types of malocclusion and 4 variables in clinical characteristics and symptoms. Clinicians treating malocclusions must attempt to clarify the cause of the occlusal condition. If caused by temporomandibular joint disease, it is important to make a proper differential diagnosis at first, and not to overlook the causative disease. Further clinical knowledge of associations between temporomandibular joint diseases and malocclusions should be accumulated, and the diagnostic tree should be improved based on new information.  相似文献   
85.
There are few case reports of hepatocellular carcinoma (HCC) metastasis to the skeletal muscle. A 78-year-old man developed a mass in the right shoulder. Washout of contrast medium during contrast-enhanced ultrasonography (CEUS) in both the primary HCC and the metastatic site was detected. Several nodules were scattered throughout the liver on an autopsy. In addition, the moderately differentiated HCC had metastasized to the right teres major muscle. Rare muscular metastasis should be considered if a hepatic tumor is moderately or poorly differentiated HCC. Early washout during CEUS is consistent with a pathological diagnosis of moderately or poorly differentiated HCC.  相似文献   
86.
ObjectiveTo examine the anatomical characteristics of impacted maxillary third molars to help predict and prevent possible adverse events during extraction.MethodsThis retrospective study enrolled young Japanese patients that were assessed for third molar extraction. Patients with maxillary third molar impaction presenting with no space between the maxillary second molar and the occlusal surface of the maxillary third molar were analysed using computed tomography data.ResultsIn this study, a total of 663 patients aged 20–29 years were examined for third molar extraction and 26 teeth in 23 patients were analysed. The mean ± SD angle between the second and third molar axes was 54.2° ± 7.5° and the mean ± SD length of the maxillary third molar was 16.1 ± 1.9 mm. The maxillary third molars showed close or extensive contact with the maxillary sinus and computed tomography did not show any bone from the maxillary sinus floor. Furthermore, in all patients, the crowns of the third molars were not completely covered by the alveolar bone.ConclusionsMaxillary third molars with horizontal impaction showed close or extensive contact with the maxillary sinus and their crowns were not completely covered by the alveolar bone.  相似文献   
87.
Rationale:Immune checkpoint inhibitors (ICIs) have shown efficacy for the treatment of various kinds of malignant tumors. However, ICIs can cause immune-related adverse events, such as arthritis. Nevertheless, the treatment of ICI-induced arthritis has not been established yet. Here we report a case of ICI-induced polyarthritis successfully treated using sarilumab and monitored using joint ultrasonography.Patient concerns:A 61-year-old man presented with polyarthritis. He had been treated with nivolumab for recurrent renal cell carcinoma 11 months before. He developed ICI-induced nephritis (proteinuria and elevated serum creatinine) 3 months before, which resolved after discontinuing nivolumab for 1 month. Two months after resuming nivolumab, he developed polyarthralgia and joint swelling, which were suspected to be associated with nivolumab administration, and hence we discontinued nivolumab again. Laboratory tests revealed elevated C-reactive protein level and erythrocyte sedimentation rate, but were negative for rheumatoid factor and anti-cyclic citrullinated peptide antibody. Joint ultrasonography revealed active synovitis in several joints, but a joint X-ray revealed no bone erosion.Diagnoses:We diagnosed polyarthritis as ICI-induced arthritis because the findings were not typical of rheumatoid arthritis (no bone erosion and seronegativity) and the patient had already developed other immune-related adverse events (ICI-induced nephritis).Interventions:After discontinuation of nivolumab, we started treatment with 15 mg daily prednisolone and 1000 mg daily sulfasalazine, although it was ineffective. Hence, we initiated 200 mg biweekly sarilumab.Outcomes:Following sarilumab administration, polyarthritis improved rapidly, and joint ultrasonography confirmed the rapid improvement of synovitis. Hence, we tapered off the glucocorticoid treatment. No recurrence of renal cell carcinoma was noted for 2 years after the initiation of sarilumab despite no anti-tumor therapy.Lessons:Sarilumab may serve as a good treatment option for treating refractory ICI-induced polyarthritis. Joint ultrasonography may contribute to the evaluation of ICI-induced polyarthritis and monitoring the effects of treatments.  相似文献   
88.
Aims/IntroductionThe purpose of the present study was to quantify errors in the diagnosis of diabetes for use in the national database, using a sufficient population size.Materials and methodsA claims database constructed by the JMDC (Tokyo, Japan), using standardized disease classifications and anonymous record linkage, was used in this validation study. We included patients with health insurance claims data from April 2005 to March 2019 in the JMDC claims database. We excluded patients without a record of specific health checkups in Japan. Sample size calculation was based on a 5% prevalence of diabetes and 0.4% absolute accuracy (i.e., 1,250,000 individuals), to calculate the sensitivity, specificity, positive predictive value and negative predictive value.ResultsIn total, 2,999,152 patients were included in this study, of which 165,515 were classified as having diabetes based on specific health checkups (validation cohort prevalence of 5.5%). The newly devised algorithm had three elements – the diagnosis‐related codes for diabetes without suspected flag, the medication codes for diabetes and then these two codes on the same record – and yielded a sensitivity of 74.6%, positive predictive value of 88.4% and Kappa Index of 0.80 (the highest values).ConclusionsIn future claims database studies, our validated algorithms will be useful as diagnostic criteria for diabetes.  相似文献   
89.
European Archives of Oto-Rhino-Laryngology - We aimed to determine whether voice rehabilitation after radiotherapy improves the quality of life (QOL), voice function, and self-rated voice function...  相似文献   
90.
In bone marrow transplantation (BMT), bone marrow cells (BMCs) have traditionally been injected intravenously. However, remarkable advantages of BMT via the intra-bone-marrow (IBM) route (IBM-BMT) over the intravenous route (IV-BMT) have been recently documented by several laboratories. To clarify the mechanisms underlying these advantages, we analyzed the kinetics of hemopoietic regeneration after IBM-BMT or IV-BMT in normal strains of mice. At the site of the direct injection of BMCs, significantly higher numbers of donor-derived cells in total and of c-kit(+) cells were observed at 2 through 6 days after IBM-BMT. In parallel, significantly higher numbers of colony-forming units in spleen were obtained from the site of BMC injection. During this early period, higher accumulations of both hemopoietic cells and stromal cells were observed at the site of BMC injection by the IBM-BMT route. The production of chemotactic factors, which can promote the migration of a BM stromal cell line, was observed in BMCs obtained from irradiated mice as early as 4 hours after irradiation, and the production lasted for at least 4 days. In contrast, sera collected from the irradiated mice showed no chemotactic activity, indicating that donor BM stromal cells that entered systemic circulation cannot home effectively into recipient bone cavity. These results strongly suggest that the concomitant regeneration of microenvironmental and hemopoietic compartments in the marrow (direct interaction between them at the site of injection) contributes to the advantages of IBM-BMT over IV-BMT. Disclosure of potential conflicts of interest is found at the end of this article.  相似文献   
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