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991.
The oral susceptibilities of 17 Culicoides species to infection with African horse sickness virus (AHSV) serotypes 3, 5 and 8 were determined by feeding field-collected midges on AHSV infected horse blood. The mean titres of virus in the bloodmeals for the three serotypes of AHSV were between 5.7 and 6.5 log10 TCID50/ml. Virus was detected, after 10 days incubation at 23.5 degrees C, in the Culicoides imicola Kieffer (Diptera: Ceratopogonidae) that had fed on blood containing AHSV 5 (8.5%) and 8 (26.8%), and in the Culicoides bolitinos Meiswinkel that had fed on AHSV 3 (3.8%), 5 (20.6%) and 8 (1.7%). Although 44.4% of the C. imicola were shown to have ingested AHSV 3 immediately after feeding, no virus was detected in 96 C. imicola after incubation. The relatively high titres of virus recorded in individual midges of both species after 10 days incubation suggested a fully disseminated infection. Previously, C. imicola was considered to be the only field vector of AHSV in Africa. Identifying C. bolitinos as a potential vector for AHSV is an important finding, which if proven will have a significant impact on our understanding of the epidemiology of AHS. No AHSVs could be detected in the other 15 species of Culicoides assayed, which suggests that some of the southern African Culicoides species are refractory to AHSV infection. However, further work with larger numbers of each species will be necessary to confirm this observation.  相似文献   
992.
993.
The essential oil of Satureja montana L. had a broad-spectrum of antimicrobial activity against 46 species of yeasts. This high and diffused activity could be used to control potential pathogenic and spoilage yeasts. The assay of MIC toward some pathogenic and spoilage yeasts showed a range values from 0.10 to 0.25 l ml–1. The MIC and growth rate reduction assay were effective tests for quantitative evaluation of antimicrobial activity.  相似文献   
994.
995.
摘要 目的:研究重组人粒细胞/巨噬细胞集落刺激因子(rhGM-CSF)联合氨磷汀治疗放射性口腔黏膜炎患者的临床治疗疗效以及对外周血淋巴细胞亚群的影响。方法:选取2019年1月到2020年12月在我院接收治疗的放射性口腔黏膜炎患者60例,随机分为对照组和rhGM-CSF组两组,每组30例。对照组接受静脉滴注氨磷汀治疗,rhGM-CSF组接受rhGM-CSF漱口液漱口联合静脉滴注氨磷汀治疗。比较两组患者临床治疗疗效、治疗后口腔黏膜炎评分、疼痛评分、吞咽功能、血清炎症因子以及外周血淋巴细胞亚型。结果:(1)rhGM-CSF组患者临床治愈率和治疗总有效率分别为26.67 %和90.00 %,均高于对照组6.67 %临床治愈率和70.00 %临床治疗总有效率(P<0.05)。(2)治疗后,rhGM-CSF组口腔黏膜炎评分、疼痛评分、吞咽功能、血清干扰素-γ(IFN-γ)、肿瘤坏死因子(TNF-α)和白介素-6(IL-6)含量均显著低于对照组患者(P<0.05)。(3)rhGM-CSF组患者治疗后外周血CD3+T淋巴细胞与对照组比较无差异(P>0.05),外周血CD4+和CD4+/CD8+T淋巴细胞亚群显著高于对照组患者,而CD8+T淋巴细胞亚群显著低于对照组患者(P<0.05)。结论:rhGM-CSF漱口液联合静脉滴注氨磷汀治疗治疗放射性口腔黏膜炎临床疗效更优,有助于减轻患者外周血炎症反应,增强细胞免疫功能。  相似文献   
996.
Eleven new yeasts from forest habitats are described from nucleotide sequence analysis of the nearly entire large subunit rRNA gene, ITS1-5.8S-ITS2 rRNA gene, mitochondrial small subunit rRNA gene, and the cytochrome oxidase II gene. All are members of the Sugiyamaella clade. Three are heterothallic species of Sugiyamaella and eight species are assigned to Candida. The Sugiyamaella species are: Su. americana sp. nov., type strain NRRL YB-2067 (CBS 10352), mating type a, and isotype NRRL YB-4197 (CBS 10353), mating type alpha; Su. chiloensis sp. nov., type strain NRRL Y-17646 (CBS 8168), mating type a, and isotype NRRL Y-27101 (CBS 5927), mating type alpha, anamorph Ca. bertae; Su. japonica sp. nov., type strain NRRL YB-2788 (CBS 10354), diploid, NRRL YB-2764 (CBS 10355), mating type a, and NRRL YB-2799 (CBS 10356), mating type alpha. The Candida species with type strains are: Ca. boreocaroliniensis sp. nov. NRRL YB-1835 (CBS 10344), Ca. floridensis sp. nov. NRRL YB-3827 (CBS 10350), Ca. grinbergsii sp. nov. NRRL Y-27117 (CBS 5924), Ca. lignohabitans sp. nov. NRRL YB-1473 (CBS 10342), Ca. marilandica sp. nov. NRRL YB-1847 (CBS 10346), Ca. marionensis sp. nov. NRRL YB-1336 (CBS 10341), Ca. neomexicana sp. nov. NRRL YB-2450 (CBS 10349), and Ca. pinicola sp. nov. NRRL YB-2263 (CBS 10348).  相似文献   
997.
Oral cancer is associated with high rates of recurrence, attributable to field cancerization. Early detection of advanced field changes that can potentially progress to carcinoma can facilitate timely intervention and can lead to improved prognosis. Previous in vivo studies have successfully detected advanced field effects in oral cancers. Raman exfoliative cytology has previously shown to differentiate normal, oral pre‐cancer and cancers. The present study explores Raman‐exfoliative‐cytology‐based detection of field effects. Exfoliated cells were collected from tumor (n = 16) and contralateral‐normal appearing mucosa (n = 16) of oral cancer patients, and healthy tobacco habitués (n = 20). After spectral acquisition, specimens were Pap‐stained for cytological evaluation. Data analysis, by Principal Component Analysis and Principal Component‐Linear Discriminant Analysis, indicate several spectral‐misclassifications between contralateral normal and tumor, which were investigated and correlated with spectral, cytological and clinical outcomes. A qualitative analysis by grouping patients with number of misclassifications with tumor (Group 1: 0, Group 2: 1 and Group 3: >1) was explored. Group 3 with highest misclassifications showed spectral and cytological similarity to tumor group — one patient was a case of early inoperable residual disease, despite clear margins on histopathology. Thus, these misclassifications could be indicative of cancer field changes, and can prospectively help to identify patients susceptible to recurrences .  相似文献   
998.
BackgroundFrance has one of the highest incidence of head and neck cancers in Europe. Despite this, the epidemiological impact of high-risk human papilloma virus (HR-HPV) remains poorly investigated.MethodsWe prospective assessed the proportion of oropharyngeal cancers due to HR-HPV in 15 hospitals throughout France. HPV-status was determined by p16-immunohistochemistry, and by detection of HPV-DNA using in situ hybridization. Cancers were classified as HPV-driven if both p16-immunohistochemistry and HPV-DNA assays were positive. Demographical and clinical features were recorded.Results291 patients with palatine-tonsil or tongue-base cancers were recruited from March-2011 to July-2012. Of these, 43.1% of samples were p16-positive and 37.7% were positive for both p16 and HPV-DNA. Prognosis was significantly better in patients with HPV-driven cancers, with smoking negatively impacting patients’ oncological outcomes.ConclusionIn France, more than a third of tonsillar and tongue base cancers are HPV-driven. More research concerning the evolution of HPV-driven cancers over time is needed.  相似文献   
999.
Oral squamous cell carcinoma (OSCC) is a highly lethal cancer in the world, and the prognosis of OSCC is poor with a 60% 5-year survival rate in recent decades. Here, we introduced a novel secretory and acid glycoprotein with cysteine rich (secreted protein acidic and rich in cysteine, SPARC), which is correlated with the worst pattern of invasion (WPOI) and prognosis of OSCC. SPARC expression levels were measured in OSCC tissues and normal tissues using quantitative polymerase chain reaction and immunohistochemistry. The influence of SPARC on cell proliferation was examined by cell counting kit-8, colony formation, and Edu tests. Then, the effect of SPARC on the metastasis of OSCC cells was detected by wound healing and transwell migration assays. Next, the biologic characteristics of SPARC shared by STRING were analyzed. Furthermore, the underlying mechanisms were confirmed by western blot analysis. SPARC revealed higher expression in OSCC tissues than nontumor tissues. Higher SPARC expression was correlated with poorer tumor differentiation, poorer WPOI pattern, and significantly and shorter overall survival. Knockdown SPARC significantly restrained OSCC cell growth, migration, and invasion. In addition, bioinformatics analysis found SPARC had a coexpression network with the platelet-derived growth factor-B (PDGFB) and PI3K/AKT signaling pathways with minimal false discovery rate. Furthermore, SPARC promotes OSCC cells metastasis by regulating the expressions of PDGFB, PDGFRβ, p-PDGFRβ , and the PI3K/AKT pathway. Higher SPARC expression was positively correlated with poor WPOI and differentiation in OSCC. SPARC activates the PI3K/AKT/PDGFB/PDGFRβ axis to promote proliferation and metastasis by OSCC cell lines. Therefore, SPARC may be a potential therapeutic target for patients with OSCC.  相似文献   
1000.
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