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《Journal of microbiology, immunology, and infection》2021,54(4):748-751
IntroductionThe novel coronavirus disease (COVID-19) could cause a severe acute respiratory infectious disease, showing a high mortality rate of 12–45% among cases who required intensive care unit admission. COVID-19 pneumoniaPatients and methodsFor the purpose of identifying clinical manifestations and radiological findings of COVID-19 pneumonia, we reviewed all cases of COVID-19 pneumonia which were published by the homepage of the Japanese Association for Infectious Diseases from Feb 5 2020 until April 30 2020, including our cases. All patients were diagnosed based on positive results of the novel coronavirus-real-time RT-PCR with chest computed tomography (CT) findings.ResultsA total of 92 patients were enrolled in this study. The median age was 66 years (range 16–92 years). For all, 50 (54%) were males. The most common underlying disease was hypertension in 32 (36%). Any comorbidity was seen in 60 (67%). The mortality rate was 4 (6%). In terms of clinical symptoms on an initial visit, fever and cough were confirmed in 66 (72%) and 37 (40%). Forty-three (47%) had no respiratory symptoms. As for radiological findings by chest CT scan, ground-glass opacities (GGO)s, peripheral distribution, bilateral lung involvements were seen in 88 (96%), 76 (83%) and 78 (85%), respectively.ConclusionIt is difficult to diagnose as COVID-19 pneumonia due to poor respiratory symptoms. Chest CT findings typically show GGO, peripheral and bilateral shadows. Patients should have chest CT performed if suspected for early diagnosis and therapeutic intervention, resulting in a favorable outcome and prevention of secondary nosocomial transmitted infection. 相似文献
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目的克隆大花胡麻草环烯醚萜合酶基因(CgIS),并进行表达分析。方法以大花胡麻草根、茎、叶转录组中唯一的CgIS基因序列为基础,采用RT-PCR技术从大花胡麻草幼叶克隆CgIS基因,并进行组织特异性表达分析。结果大花胡麻草CgIS基因(GenBank登录号MH794270)全长1 185 bp,编码394个氨基酸;CgIS蛋白相对相对分子质量44 670,理论pI为6.17;该蛋白属于孕酮5β-还原酶(P5β-R)家族成员,可能定位于细胞质;该蛋白无信号肽,为亲水稳定蛋白,主要由α-螺旋(40.61%)和无规则卷曲(46.70%)构成;该蛋白具有SDR(短链脱氢酶/还原酶)和P5βR蛋白保守结构域;CgIS蛋白与芝麻SiIS蛋白亲缘关系最近;CgIS基因主要在叶中表达。结论克隆了CgIS基因,并对其进行表达分析,为进一步研究该基因的功能和环烯醚萜类的生物合成途径奠定基础。 相似文献
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目的常年监测分析上海市南翔地区呼吸道感染儿童病毒病原学情况。方法采集2007年1月至2013年9月门诊急性呼吸道感染患儿4 389例鼻咽分泌物,多重逆转录PCR法(Multiplex RT-PCR)检测9种呼吸道病毒,包括流感病毒(FLU)、副流感病毒(PIV)、呼吸道合胞病毒(RSV)、腺病毒(ADV)、人博卡病毒(HBOV)、人冠状病毒(Cov)、肠病毒(EV)、人偏肺炎病毒(HMPV)、鼻病毒(HRV)。同期采集无呼吸道感染症状儿童鼻咽分泌物标本123例,同时多重逆转录PCR法检测9种呼吸道病毒。结果 4 389例呼吸道感染患儿鼻咽分泌物标本中呼吸道病毒阳性检出率为34.8%(1526/4389),前3位病毒依次为FLU 10.3%(453/4389)、RSV 7.3%(320/4389)和PIV 6.2%(274/4389);2种及2种以上呼吸道病毒混合感染273例(6.2%)。不同年龄组病毒总检出率差异有统计学意义(χ2=41.91,P0.001),学龄组儿童检出率最低为23.4%,其余3组检出率均≥35.0%;RSV、HRV在婴儿组检出率均较高;FLU在学龄组儿童中检出率较高为13.6%。儿童喘息性疾病中存在较高的病毒检出率,其中RSV检出率14.8%(30/204),其次为HBOV 13.8%(28/204)。同期采集无呼吸道感染症状儿童鼻咽分泌物标本123例,病毒检出率6.5%(8/123),与呼吸道感染组病毒检出率比较,差异有统计学意义(χ2=42.60,P0.001)。结论在连续7年的常年检测中,FLU、RSV在该地区儿童呼吸道感染性疾病中占重要地位。不同年龄组病毒检出率存在差异,婴幼儿呼吸道感染有较高的病毒检出率,RSV检出率较高;随年龄增长,总体病毒检出率下降,但流感病毒在大年龄组的检出率增高。 相似文献
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Knowledge of the molecular events that occur in carious disease has so far been constrained due to difficulties in obtaining sufficient quantities of the dental tissues and cells involved. Our histological findings indicate that a pulp-odontoblast cellular complex can be obtained from carious and healthy human teeth when exposed to low-temperatures prior to pulpal extirpation and from rodent teeth processed at room-temperature. In contrast, pulpal tissue extracted from room-temperature processed human teeth and low-temperature processed rodent teeth resulted in the odontoblast layer remaining attached to the pulp chamber. Semi-quantitative RT-PCR (sq-RT-PCR) analysis confirmed that markers previously shown to be preferentially expressed in odontoblasts, namely dentin sialophosphoprotein (DSPP) and Nestin, amplified more readily from the extracted pulp-odontoblast complex, as compared to pulpal tissue alone, in both human and rodent samples. Subsequent gene expression analysis of collagen-1alpha and collagen-3alpha indicated levels were significantly higher in carious pulpal tissue. In addition, analysis characterising the expression of members of the transforming growth factor and bone morphogenic protein families and their receptors indicated in general, that these genes were expressed by healthy odontoblasts and up-regulated in both pulpal cells and odontoblasts in response to carious injury. Use of this temperature-sensitive dental tissue preparation procedure allows detection of differential gene expression in odontoblasts and other pulpal cells in healthy and carious tissue. 相似文献
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OBJECTIVE: To assess the feasibility of using archival oral mucosal tissue to examine gene expression at the ribonucleic acid (RNA) level.
MATERIALS AND METHODS: We describe the isolation of RNA from 8 nm sections of formalin-fixed paraffin-embedded oral mucosal tissue. RNA was reverse transcribed and three candidate genes amplified by polymerase chain reaction (PCR). The ribosomal protein S14 gene is a housekeeping gene which has been used as an internal standard in several quantitative PCR protocols. The thymidine kinase (TK) gene is expressed at low levels in most tissues and, with a well-documented genomic organisation, is a useful tool for discrimination between genomic DNA and cDNA. The RIa gene is reported to be overexpressed in many cancer cell lines, in malignant tissue and in vitro transformed cellS. RESULTS: The S14 gene, the TK gene and the RIα gene of the cAMP-dependent protein kinase (PKA) were amplified successfully from formalin-fixed paraffin-embedded tissue sections. The TK primer pair is a useful additional tool in the unambiguous identification of RNA-derived species.
CONCLUSION: RNA suitable for reverse transcribed (RT)-PCR was extracted from archival oral mucosal tissue. This should permit rapid sequence analysis of transcribed tumor suppressor genes and oncogenes in this material. Furthermore, the RT-PCR approach described may allow quantification of gene expression in oral mucosal archival material processed in a standard fashion. 相似文献
MATERIALS AND METHODS: We describe the isolation of RNA from 8 nm sections of formalin-fixed paraffin-embedded oral mucosal tissue. RNA was reverse transcribed and three candidate genes amplified by polymerase chain reaction (PCR). The ribosomal protein S14 gene is a housekeeping gene which has been used as an internal standard in several quantitative PCR protocols. The thymidine kinase (TK) gene is expressed at low levels in most tissues and, with a well-documented genomic organisation, is a useful tool for discrimination between genomic DNA and cDNA. The RIa gene is reported to be overexpressed in many cancer cell lines, in malignant tissue and in vitro transformed cellS. RESULTS: The S14 gene, the TK gene and the RIα gene of the cAMP-dependent protein kinase (PKA) were amplified successfully from formalin-fixed paraffin-embedded tissue sections. The TK primer pair is a useful additional tool in the unambiguous identification of RNA-derived species.
CONCLUSION: RNA suitable for reverse transcribed (RT)-PCR was extracted from archival oral mucosal tissue. This should permit rapid sequence analysis of transcribed tumor suppressor genes and oncogenes in this material. Furthermore, the RT-PCR approach described may allow quantification of gene expression in oral mucosal archival material processed in a standard fashion. 相似文献