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991.
目的 分析儿童7型腺病毒肺炎的临床特征,以提高诊疗水平、改善预后。方法 回顾性分析2019年4月~7月我院收治的42例7型腺病毒肺炎患儿的临床资料,包括临床表现、实验室检查指标及影像学结果、恢复期肺功能检查、脏器功能受累情况、合并其他病原感染情况、治疗结局。结果 共42例患儿中,2岁以下29例(69.05%),均有发热,热峰>40℃ 33例(78.57%),热程≥2周19例(45.24%)。42例患儿LDH、AST、ALT均升高,ALB降低;随着热程时间延长,LDH、AST水平升高,ALB下降,其余指标均无明显差异。影像学表现节段性实变,9例患儿初期胸片或CT表现以单侧节段性实变为主,23例患儿以双侧散发与节段性实变为主,入院1~3 d内复查胸片或CT,双侧实变迅速发展至26例(61.90%)。肺外合并症主要为血液系统损害(30.95%)为主。病原感染主要以合并肺炎支原体IgM阳性13例(30.95%)为主。呼吸支持包括鼻导管给氧9例(21.42%),无创通气24例(57.14%),机械通气9例(21.42%)。住院期间死亡3例,3例患儿因病情危重转至上级医院,其中2例死亡,1例遗留严重后遗症;其余36例(85.71%)治愈、好转出院。结论 儿童7型腺病毒肺炎热峰高,热程长,LDH、AST明显升高,影像学进展快,常伴肺内外各种损害。临床疑诊7型腺病毒肺炎时应尽快完善病原学,动态监测LDH、AST水平及影像学变化,及早治疗。 相似文献
992.
《Clinical microbiology and infection》2020,26(2):247-254
ObjectivesDespite the importance of immunological memory for protective immunity against viral infection, whether H7N9-specific antibodies and memory T-cell responses remain detectable years after the original infection is unknown.MethodsA cross-sectional study was conducted to investigate the immune memory responses of H7N9 patients who contracted the disease and survived during the 2013–2016 epidemics in China. Sustainability of antibodies and T-cell memory to H7N9 virus were examined. Healthy individuals receiving routine medical examinations in a physical examination centre were recruited as control.ResultsA total of 75 survivors were enrolled and classified into four groups based on the time elapsed from illness onset to specimen collection: 3 months (n = 14), 14 months (n = 14), 26 months (n = 28) and 36 months (n = 19). Approximately 36 months after infection, the geometric mean titres of virus-specific antibodies were significantly lower than titres in patients 3 months after infection, but 16 of 19 (84.2%) survivors in the 36-month interval had microneutralization (MN) titres ≥40. Despite the overall declining trend, the percentages of virus-specific cytokine-secreting memory CD4+ and CD8+ T cells remained higher in survivors at nearly all time-points in comparison with control individuals. Linear regression analysis showed that severe disease (mean titre ratio 2.77, 95% CI 1.17–6.49) was associated with higher haemagglutination inhibition (HI) titre and female sex for both HI (1.92, 1.02–3.57) and MN (3.33, 1.26–9.09) antibody, whereas female sex (mean percentage ratio 1.69, 95% CI 1.08–2.63), underlying medical conditions (1.94, 95% CI 1.09–3.46) and lack of antiviral therapy (2.08, 95% CI 1.04–4.17) were predictors for higher T-cell responses.ConclusionsSurvivors of H7N9 virus infection produced long-term antibodies and memory T-cell responses. Our findings warrant further serological investigation in general and high-risk populations and have important implications for vaccine design and development. 相似文献
993.
《European journal of medical genetics》2020,63(5):103872
Microdeletions in the 9q22.3 chromosomal region can cause macrosomia with characteristic features, including prenatal-onset overgrowth, metopic craniosynostosis, hydrocephalus, developmental delay, and intellectual disability, in addition to manifestations of nevoid basal cell carcinoma syndrome (NBCCS). Haploinsufficiency of PTCH1 may be responsible for accelerated overgrowth, but the mechanism of macrosomia remains to be elucidated. We report a familial case with a 9q22.3 microdeletion, manifesting with prenatal-onset overgrowth in a mother and post-natal overgrowth in her daughter. Although both were clinically diagnosed with NBCCS, they had characteristic features of 9q22.3 microdeletion, especially the daughter. Microarray comparative genomic hybridization analysis revealed a 4.0 Mb deletion of chromosome 9q22.3 in both individuals. Among the 11 reported patients of overgrowth and/or macrosomia, a 550 Kb region encompassing PTCH1, C9orf3, FANCC, and 5 miRNAs is the most commonly deleted region. The let-7 family miRNAs, which are involved in diverse cellular processes including growth and tumor processes, were identified in the deleted regions in 10 of 11 patients. Characteristic features of 9q22.3 microdeletion might be associated with decreased expression of let-7. 相似文献
994.
Bing Zou Alexandra A. Desmidt Rahul Mittal Denise Yan Micheal Richmond Mustafa Tekin Xue Zhong Liu Zhongmin Lu 《Anatomical record (Hoboken, N.J. : 2007)》2020,303(3):556-562
Targeted genome editing mediated by clustered, regularly interspaced, short palindromic repeat (CRISPR)/CRISPR-associated nuclease 9 (Cas9) technology has emerged as a powerful tool for gene function studies and has great potential for gene therapy. Although CRISPR/Cas9 has been widely used in many research fields, only a few successful zebrafish models have been established using this technology in hearing research. In this study, we successfully created zebrafish mariner mutants by targeting the motor head domain of Myo7aa using CRISPR/Cas9. The CRISPR/Cas9-generated mutants showed unbalanced swimming behavior and disorganized sterocilia of inner ear hair cells, which resemble the phenotype of the zebrafish mariner mutants. In addition, we found that CRISPR/Cas9-generated mutants have reduced number of stereociliary bundles of inner ear hair cells and have significant hearing loss. Furthermore, phenotypic analysis was performed on F0 larvae within the first week post fertilization, which dramatically shortens data collection period. Therefore, results of this study showed that CRISPR/Cas9 is a quick and effective method to generate zebrafish mutants as a model for studying human genetic deafness. Anat Rec, 303:556–562, 2020. © 2019 American Association for Anatomy 相似文献
995.
目的 探讨缺血预适应(IPC)动员肾祖细胞(RPC)归巢在保留肾单位手术(NSS)中对肾脏缺血再灌注损伤(IRI)的保护作用及其发生机制。方法 选取2~3月龄、体质量250~300 g的雄性SD大鼠54只,建立切除右肾的单肾模型后采用数字表法随机分为3组,每组18只:假手术组(Sham组,无血管夹闭),NSS组(肾动脉夹闭45 min后行NSS),IPC组(先进行肾动脉夹闭15 min,再灌注10 min预处理,再行NSS)。分别在术后12、24、72 h每组各取出6只大鼠,收集血液及肾组织标本,之后采用颈椎脱臼法处死大鼠。观察项目:(1)检测血肌酐(SCr)、尿素氮(BUN);(2)组织病理学检查及肾小管损伤评分;(3)在24 h观察IPC对肾组织中RPC数量的影响,以及IPC对基质细胞衍生因子(SDF-1)、受体CXCR7表达水平的影响。结果 (1)术后12、24、72 h 时3组大鼠SCr和BUN值比较, IPC组分别为(65.0±10.78)、(91.5±15.12)、(52.6±11.68)μmol/L和(14.78±2.77)、(18.31±4.99)、(9.41±2.73)mmol/L,NSS组分别为(80.5±12.63)、(116.9±14.32)、(83.7±11.43)μmol/L和(18.58±4.18)、(28.86±5.64)、(19.49±3.83)mmol/L, Sham组分别为(41.5±7.36)、(39.7±7.55)、(42.7±7.15)μmol/L和(7.72±1.75)、(7.40±1.98)、(6.83±2.09)mmol/L;除72 h时IPC组与Sham组SCr和BUN值比较差异无统计学意义(P>0.05)外,在12 h和24 h,IPC组均高于Sham组、低于NSS组,差异均有统计学意义(P值均<0.05)。(2)术后12、24、72 h肾小管损伤评分IPC组和NSS组均高于Sham组,术后12、24 h IPC组较NSS组肾小管损伤评分低,差异均有统计学意义(P值均<0.05)。(3)术后24 h,IPC组和NSS组大鼠肾组织中RPC数量明显增加、SDF-1和CXCR7表达显著升高,差异均有统计学意义(P值均<0.05)。结论 IPC可促进RPC归巢,缓解NSS中IRI损伤程度,保护肾功能,SDF-1/CXCR7轴可能在这一动员过程中发挥了重要作用。 相似文献
996.
997.
Gordana Leposavić Milica Perišić Nanut Ivan Pilipović Duško Kosec Nevena Arsenović-Ranin Zorica Stojić-Vukanić Jasmina Djikić Mirjana Nacka-Aleksić 《Immunobiology》2014
This study explores the role of ovarian hormones in the phenotypic shaping of peripheral T-cell pool over the reproductive lifespan of rats. For this purpose, 2-month-old prepubertally ovariectomised (Ox) rats, showing oestrogen and progesterone deficiency, and 11-month-old Ox rats, exhibiting only progesterone deficiency, were examined for thymus output, and cellularity and composition of major TCRαβ+ peripheral blood lymphocyte (PBL) and splenocyte subsets. Although ovariectomy increased thymic output in both 2- and 11-month-old rats, the count of both CD4+ and CD8+ PBLs and splenocytes increased only in the former. In the blood and spleen of 11-month-old Ox rats only the count of CD8+ cells increased. Although ovariectomy affected the total CD4+ count in none of the examined compartments from the 11-month-old rats, it increased CD4+FoxP3+ PBL and splenocyte relative proportions over those in the age-matched controls. The age-related differences in the cellularity and the major subset composition in Ox rats were linked to the differences in the ovarian steroid hormone levels registered in 2- and 11-month-old rats. The administration of progesterone to Ox rats during the seven days before the sacrificing confirmed contribution of this hormone deficiency to the ovariectomy-induced changes in the TCRαβ+ PBL and splenocyte pool from 11-month-old rats. The expansion of the CD8+ splenocyte subset in the 11-month-old Ox rats reflected increases in cellularity of memory and, particularly, naïve cells. This was due to greater thymic output of CD8+ cells and homeostatic proliferation than apoptosis in 11-month-old Ox rats when compared with age-matched sham-Ox control rats. The homeostatic changes within CD8+ splenocyte pool from 11-month-old Ox rats, most likely, reflected the enhanced splenic IL-7 and TGF-β mRNA expression. Overall, in adult female rats, circulating oestrogen and progesterone provide maintenance of T-cell counts, a diversity of T-cell repertoire, and the main T-cell subset composition in the periphery. Progesterone deficiency affects mainly the CD8+ lymphocyte compartment through increasing thymic CD8+ cell export and upsetting homeostatic regulation within the CD8+ splenocyte pool. These alterations were reversible through progesterone supplementation. 相似文献
998.
Weiling Li Ye Li Yuwan Zhao Jieli Yuan Weifeng Mao 《African journal of traditional, complementary, and alternative medicines》2014,11(5):105-110
Background
To observe the inhibition effects of the Buthus matensii Karsch (BmK) scorpion venom extracts on the growth of human breast cancer MCF-7 cells, and to explore its mechanisms.Methods
Two common tumor cells (SMMC7721, MCF-7) were examined for the one which wasmore sensitivity to scorpion venom by MTT method. Cell cycle was determined by flow cytometry. Immunocytochemistry was applied to detect apoptosis-related protein Caspase-3 and Bcl-2 levels, while the expression of cell cycle-related protein Cyclin D1 was shown by Western blotting.Results
Our data indicated that MCF-7 was the more sensitive cell line to scorpion venom. The extracts of scorpion venom could inhibit the growth and proliferation of MCF-7 cells. Furthermore, the extract of scorpion venom induced apoptosis through Caspase-3 up-regulation while Bcl-2 down-regulation in MCF-7 cells. In addition, the extracts of scorpion venom blocked the cells from G0/G1 phase to S phase and decreased cell cycle-related protein Cyclin D1 level after drug intervention compared with the negative control group.Conclusions
These results showed that the BmK scorpion venom extracts could inhibit the growth of MCF-7 cells by inducing apoptosis and blocking cell cycle in G0/G1 phase. The BmK scorpion venom extracts will be very valuable for the treatment of breast cancer. 相似文献999.
Bharat Rekhi Sajid Shafique Qureshi Gaurav Narula Sumeet Gujral Purna Kurkure 《Pathology, research and practice》2014
Congenital rhabdomyosarcomas (RMSs) are rare tumors with variable clinical presentations. A 2 month-old, term male neonate (37 weeks, 4 days), weighing 3.2 kg, born to a 24 year-old primigravida, by simple vaginal delivery presented with multiple erythematous papulonodular lesions over his trunk that progressed to his whole body, on the first day of delivery. Prior to conception, his mother was treated for polycystic ovarian disease. On the tenth day, his chest computed tomogram scans revealed multiple, heterogeneously enhancing, bilateral pleural-based soft tissue density nodular lesions, along with multiple soft tissue density lesions, involving skeletal muscles of all his body parts. Microsections from two biopsies (on 10th day and after 2 months) revealed a malignant round cell tumor with cells arranged in a diffuse, solid pattern, comprising embryonal and solid alveolar components. Immunohistochemically, the tumor cells were diffusely positive for desmin, myoD1 and myogenin. Diagnosis of embryonal and alveolar (mixed type) RMS was offered. Further molecular cytogenetic analysis was negative for PAX3-FKHR and PAX7-FKHR. The patient was induced on chemotherapy as per intergroup rhabdomyosarcoma study IV protocol. There was treatment response with near total remission after 8 weeks of treatment. Thereafter, new lesions started appearing that also disappeared after modification of the chemotherapy drugs. However, after 16 months, the baby died of brain metastasis. The present case forms the fourth case report of an aggressive form of a congenital RMS with extensive cutaneous involvement and brain metastasis. A review of previously diagnosed cases of congenital RMSs is discussed herewith. 相似文献
1000.
《Pathology, research and practice》2014,210(12):1090-1094
The strong association of diagnostic karyotype with clinical outcome has made cytogenetics one of the most valuable diagnostic and prognostic tools for acute myeloid leukemia (AML) till today. Complex chromosomal findings are reported to be seen in nearly 10–15% of adult AMLs and are generally associated with poor outcome. In the current report, we present the results of hematologic, immunophenotypic, cytogenetic, chromosomal microarray and molecular analyses of a 60-year-old female patient diagnosed with AML-M2. Cytogenetic analysis revealed complex chromosomal findings involving seven different chromosomes. However, cytogenetic analyses were not able to precisely unveil all karyotypic changes, hence chromosomal microarray was used for further characterization. The most interesting observation was identification of a t(7;12) (q11;q22) as part of this complex karyotype. To the best of our knowledge, this is the first report of identification of novel t(7;12) (q11;q22) as part of a complex karyotype in de novo AML-M2. 相似文献