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1.
[摘要] 目的 探讨上海某方舱医院新型冠状病毒奥密克戎变异株感染者的发病情况及流行病学特征。方法 以2022年4月9日—5月5日上海国家会展中心方舱医院收治的新型冠状病毒奥密克戎变异株感染者为研究对象,对感染者年龄、性别、地区、疫苗接种等疫情数据进行流行病学特征分析。结果 122 151例新型冠状病毒感染者均为奥密克戎变异株BA.2或BA.2.2亚型感染,其流行病学特征结果显示:患者男女比例为1.51:1;平均年龄为(44.91±15.38)岁;0~17岁、18~30岁、31~60岁和≥61岁感染者分别占4.74%、20.80%、62.52%和11.94%;无症状感染者占80.80%,轻型患者占19.20%;平均住院时间为(7.00±2.77)d;未接种和完成1、2和3次疫苗接种的感染者分别占20.30%、3.18%、31.30%和45.22%,其中≥61岁且完成3次疫苗接种的感染者仅占10.10%。结论 各个年龄段人群对于新型冠状病毒奥密克戎变异株普遍易感。无症状感染者是本次疫情的主体人群,临床症状不典型,早期隐匿传播,积极加强核酸检测是早期发现疫情的必要手段。  相似文献   
2.
IntroductionDetailed data on clinical characteristics in children with the omicron strain of SARS-COV-2 are limited.MethodsWe conducted a retrospective observational study of children with COVID-19 at the National Center for Child Health and Development to evaluate the clinical manifestations during and before the emergence of the omicron variant. Only symptomatic patients without underlying diseases were included. Participants were divided into two temporal groups: the “omicron era” (1/2022–2/2022) and the “pre-omicron era,” where the delta variant predominated (7/2021–11/2021). The patients were subclassified into an older vaccine-eligible group (aged 12–17 years), a younger vaccine-eligible group (aged 5–11 years), and a vaccine-ineligible group (aged 0–4 years).ResultsWe compared 113 patients in the omicron era with 106 in the pre-omicron era. Most patients in both eras had non-severe disease, and no patients required mechanical ventilation or died. Among patients aged 0–4 years, sore throat and hoarseness were more common during the omicron era than the pre-omicron era (11.1% vs. 0.0% and 11.1% vs. 1.5%, respectively). Croup syndrome was diagnosed in all patients with hoarseness. Among patients aged 5–11 years, vomiting was more frequent during the omicron era (47.2%) than during the pre-omicron era (21.7%). Cough and rhinorrhea were less common during the omicron era in patients aged 0–4 and 5–11 years, respectively, than during the pre-omicron era.ConclusionsIn children with COVID-19, clinical manifestations differed between the omicron and pre-omicron eras. In the Omicron era, croup syndrome was more frequent in vaccine-ineligible children.  相似文献   
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  • DNA is the sequence that codes for proteins.
  • Messenger RNA is transcribed from the DNA sequence of genes and translated into protein.
  • It can be difficult to predict how a change in the DNA sequence will affect messenger RNA and protein quantity and quality.
  • DNA translocation changes can cause the joining of sequences from two different genes or different parts of the same gene.
  • DNA sequencing is often used clinically to predict how DNA changes might affect proteins.
  • Alternatively, RNA sequencing can be used as a more direct measure of the effect of DNA changes on the protein products.
  • This sequencing is important for identifying changes in cancer that may indicate response to targeted therapy, prognosis, or diagnosis.
  相似文献   
5.
《Molecular therapy》2022,30(5):1979-1993
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6.
Bedaquiline is a new ATP synthesis inhibitor developed as an anti-tuberculosis agent. It has resistance-associated variants (RAV), regardless of preceding bedaquiline exposure. Herein, we describe the case of a patient with multidrug-resistant tuberculosis (MDR-TB) who had no history of bedaquiline therapy but presented a relatively high minimum inhibitory concentration (MIC) of bedaquiline (1 μg/mL). Whole genome sequencing revealed a mutation in the resistance-associated gene Rv0678. The patient was first treated with a five-drug regimen (bedaquiline, delamanid, levofloxacin, cycloserine, and amikacin), which induced negative sputum culture conversion. Despite the successful treatment outcome, several questions remain regarding the efficacy of bedaquiline in this patient. Bedaquiline is an indispensable drug for MDR-TB treatment, but its clinical efficiency in the presence of Rv0678 mutations remains unclear. Therefore, evaluating the MIC of bedaquiline even in patients without a history of bedaquiline use is important for therapeutic regimen selection and may emphasize the importance of therapeutic drug monitoring in cases of bedaquiline RAV.  相似文献   
7.
 自2021年11月新型冠状病毒奥密克戎变异株出现以来,几个月内迅速席卷全球。世界各国都出现了以奥密克戎为主要流行毒株的新一轮疫情,我国香港、深圳、上海等城市也未能幸免。奥密克戎刺突蛋白含有大量突变,具有强大的免疫逃逸能力,对现有的疫苗和抗体相关治疗造成了巨大的威胁。虽然奥密克戎变异株引起的疾病症状较轻,但由于其超高的传播率,全球卫生系统均承受了巨大的压力。本文就奥密克戎变异株的病原学特征、变异来源、传播特征、流行现状及防治措施等方面进行综述,以期为科学防控提供参考。  相似文献   
8.
钟晓梅  万娟  张莉  唐光群  廖婷 《西部医学》2022,34(10):1512-1516
目的 探讨咳嗽变异性哮喘(CVA)患儿血清可溶性程序性死亡配体1(sPD-L1)、Toll样受体4(TLR4)和可溶性细胞间粘附分子-1(sICAM-1)水平及临床意义。方法 纳入我院162例CVA患儿临床资料行前瞻性研究,根据其临床分期分为CVA急性期组(90例).与CVA缓解期组(72例);并收集同期入院的124例典型支气管哮喘(CA)患者临床资料,根据其临床分期分为CA急性期组(66例)与CA缓解期组(58例),另纳入36例非呼吸系统疾病患儿作为对照组。比较各组血清sPD-L1、TLR4和sICAM-1水平及肺功能[用力肺活量(FVC)、一秒用力呼气容积(FEV1)、最大呼气中段流量(MMEF)]、气道反应性及敏感性[初始阻力值(Rrs cont)、基础呼吸传导率(Grs cont)、最小诱发累积剂量(Dmin)、传导率下降斜率(sGrs)]差异,并评估CVA患儿肺功能、气道反应性、敏感性与血清sPD-L1、TLR4和sICAM-1水平的关系。 结果 5组性别、年龄、身高、体重及Rrs cont、Grs cont比较,差异无统计学意义(P>0.05)。5组血清sPD-L1水平及FVC、FEV1、MMEF、Dmin、sGrs比较,CA急性期组<CVA急性期组<CA缓解期组<CVA缓解期组<对照组(均P<0.05),5组血清TLR4、sICAM-1水平比较,CA急性期组>CVA急性期组>CA缓解期组>CVA缓解期组>对照组(均P<0.05)。经Pearson相关性分析,发现CVA患儿FVC、FEV1、MMEF及Dmin、sGrs与血清sPD-L1水平呈显著正相关(P<0.05),与血清TLR4和sICAM-1水平呈显著负相关(P<0.05)。 结论 血清sPD-L1、TLR4和sICAM-1水平与CVA患儿肺功能、气道反应性及敏感性相关,对判断病情发展有利。  相似文献   
9.
Lesch-Nyhan综合征是一种罕见的X连锁隐性遗传病,在自伤行为出现前,易被误诊为脑瘫,延误诊治。先证者,男,8岁7个月,因发育落后8年余,肌张力异常就诊。多次血生化均提示尿酸增高,遗传学分析结果证实患儿为HPRT1基因c.200_201delTG变异,经ACMG评级为疑似致病性变异,Sanger测序验证发现该变异遗传自患儿母亲,为未报道的新变异,从而确诊为HPRT1基因相关Lesch-Nyhan综合征,口服别嘌醇片、碳酸氢钠片6月后尿酸水平较前明显下降,仍无自伤行为。临床上遇到不明原因脑瘫表现者,应及早行遗传学检查,以帮助早期诊断和遗传咨询。  相似文献   
10.
PurposeStudies conducted primarily among European ancestry women reported 12 breast cancer predisposition genes. However, etiologic roles of these genes in breast cancer among African ancestry women have been less well-investigated.MethodsWe conducted a case-control study in African American women, which included 1117 breast cancer cases and 2169 cancer-free controls, and a pooled analysis, which included 7096 cases and 8040 controls of African descent. Odds ratios of associations with breast cancer risk were estimated.ResultsUsing sequence data, we identified 61 pathogenic variants in 12 breast cancer predisposition genes, including 11 pathogenic variants not yet reported in previous studies. Pooled analysis showed statistically significant associations of breast cancer risk with pathogenic variants in BRCA1, BRCA2, PALB2, ATM, CHEK2, TP53, NF1, RAD51C, and RAD51D (all P < .05). The associations with BRCA1, PALB2, and RAD51D were stronger for estrogen receptor (ER)-negative than for ER-positive breast cancer (P heterogeneity < .05), whereas the association with CHEK2 was stronger for ER-positive than for ER-negative breast cancer.ConclusionOur study confirmed previously identified associations of breast cancer risk with BRCA1, BRCA2, PALB2, ATM, TP53, NF1, and CHEK2 and provided new evidence to extend the associations of breast cancer risk with RAD51C and RAD51D, which was identified previously in European ancestry populations, to African ancestry women.  相似文献   
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