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61.
Mutations in the cationic trypsinogen gene and evidence for genetic heterogeneity in hereditary pancreatitis 总被引:9,自引:0,他引:9 下载免费PDF全文
Férec C Raguénès O Salomon R Roche C Bernard JP Guillot M Quéré I Faure C Mercier B Audrézet MP Guillausseau PJ Dupont C Munnich A Bignon JD Le Bodic L 《Journal of medical genetics》1999,36(3):228-232
Hereditary pancreatitis (HP) is a rare inherited disorder, characterised by recurrent episodes of pancreatitis often beginning in early childhood. The mode of inheritance suggests an autosomal dominant trait with incomplete penetrance. The gene, or at least one of the genes, responsible for hereditary pancreatitis has been mapped to the long arm of chromosome 7 and a missense mutation, an arginine to histidine substitution at residue 117 in the trypsinogen cationic gene (try4) has been shown to segregate with the HP phenotype. The aim of this work was to investigate the molecular basis of hereditary pancreatitis. This study was performed on 14 HP families. The five exons of the trypsinogen cationic gene were studied using a specific gene amplification assay combined with denaturing gradient gel electrophoresis (DGGE). The present paper describes three novel mutations, namely K23R and N29I and a deletion -28delTCC in the promoter region. We also found a polymorphism in exon 4, D162D. In eight of these families we found a mutation which segregates with the disease. A segregation analysis using microsatellite markers carried out on the other families suggests genetic heterogeneity in at least one of them. Our findings confirm the implication of the cationic trypsinogen gene in HP and highlight allelic diversity associated with this phenotype. We also show that the pattern of inheritance of HP is probably complex and that other genes may be involved in this genetic disease. 相似文献
62.
ADA活性紫外吸收测定法的改良及复感儿淋巴细胞该酶活性的检测 总被引:2,自引:0,他引:2
检测了42例健康儿童和17例反复上呼吸道感染患儿(复感儿)的血淋巴细胞腺苷脱氨酶(ADA)活性,结果表明:复感儿的血淋巴细胞中ADA活性较健康儿童低下,且大多同样伴有不同程度的免疫功能低下;从复感儿组中筛选了两侧ADA活性和免疫功能明显低下的患儿,拟采用这两例患儿的血淋巴细胞进行ADA-SCID基因治疗的实验研究。 相似文献
63.
64.
目的 探讨携带外源基因的慢病毒在体外有效感染胰岛及外源基因在胰岛中的表达,为通过移植前向胰岛细胞转入特定的免疫调节分子基因诱导胰岛移植物耐受奠定基础。方法 将目的基因CTLA4Ig导入慢病毒载体pWPTS,构建成pWPTS-CTLA4Ig载体。用磷酸钙沉淀法将pWPTS-EGFP、pWPTS-CTLA4Ig分别和其辅助载体pMD2.G、pCMVΔ8.92共转染293T细胞,收获病毒上清液,测定病毒滴度后感染新分离的胰岛。通过Western Blot测定胰岛培养上清液中CTLA4Ig蛋白的表达。结果 ①成功构建了携带CTLA4Ig基因的慢病毒载体pWPTS-CTLA4Ig;②包装产生的慢病毒Lenti-EGFP、Lenti-CTLA4Ig在体外可以感染胰岛,其中在Lenti-EGFP慢病毒感染的胰岛观察到了绿色荧光,及在Lenti-CTLA4Ig慢病毒感染的胰岛培养上清液中检测到了CTLA4Ig蛋白的表达。结论 慢病毒在体外可以有效感染大鼠胰岛,且携带的外源基因可以在胰岛细胞中稳定表达,其中Lenti-CTLA4Ig慢病毒感染的胰岛为进行胰岛移植并诱导体内特异的胰岛移植物耐受奠定了基础。 相似文献
65.
T. Koga R. Qu Hiroyuki Fukuda 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,118(2):139-147
There is some controversy over whether or not a discrete site that integrates vomiting activities in somatic and autonomic
nerves is present in the medulla oblongata. On the basis of our previous studies, we hypothesized that the temporal patterns
of muscle contractions in vomiting are generated by a central pattern generator in the retrofacial area of the rostral medulla.
To investigate this hypothesis further, the effects of electrical and chemical lesions of the medullary area were observed
in decerebrate paralyzed dogs. Efferent activities of the phrenic and abdominal muscle nerves were recorded to recognize fictive
vomiting. The right half of the medulla oblongata was transversely severed about 3 mm rostral to the obex. Fictive vomiting
responses to vagal stimulation still appeared after hemisection in all 11 dogs. In addition, stimulation of the contralateral
reticular area dorsomedial to the retrofacial nucleus produced fictive vomiting even after hemisection. An electrical lesion
or injection of kainic acid (0.5–1.0 μl) was applied at the point where reticular stimulation induced fictive vomiting. After
this destruction, no activities that corresponded to fictive vomiting could be induced by stimulation of vagal afferents or
the reticular site. Salivation was decreased by hemisection, and decreased further, but was not completely abolished, with
destruction of the reticular area. Kainic acid is known to selectively destroy neural cell bodies. Therefore, we concluded
that neuronal somata in the reticular formation dorsomedial to the retrofacial nucleus play an essential role in the central
patterning of vomiting activities in peripheral motor nerves.
Received: 10 September 1996 / Accepted: 2 July 1997 相似文献
66.
An adaptive algorithm is described that groups motor unit action potentials (MUAPs), detected in a composite EMG signal during
signal decomposition, and creates partial motor unit action potential trains (MUAPTs). Data-driven MUAP shape and motor unit
firing-pattern based criteria are used to form the clusters. An algorithm for estimating MUAPT temporal parameter, which provides
accurate estimates even for partially defined trains, is used to obtain firing-pattern information. No a priori knowledge
is required regarding the number of clusters or the distribution of their template shapes. The clustering algorithm when applied
to real concentric-needle detected MUAP data provides accurate and useful clustering results. Compared to a classical leader-based
algorithm, it provides more robust performance, is better able to estimate the true number of motor units represented in a
set of detected MUAPs, and obtains more complete and accurate MUAPTs. 相似文献
67.
Richard P Metz Xiaoyu Qu Brian Laffin David Earnest Weston W Porter 《Developmental dynamics》2006,235(1):263-271
Mouse mammary epithelial cells (HC-11) and mammary tissues were analyzed for developmental changes in circadian clock, cellular proliferation, and differentiation marker genes. Expression of the clock genes Per1 and Bmal1 were elevated in differentiated HC-11 cells, whereas Per2 mRNA levels were higher in undifferentiated cells. This differentiation-dependent profile of clock gene expression was consistent with that observed in mouse mammary glands, as Per1 and Bmal1 mRNA levels were elevated in late pregnant and lactating mammary tissues, whereas Per2 expression was higher in proliferating virgin and early pregnant glands. In both HC-11 cells and mammary glands, elevated Per2 expression was positively correlated with c-Myc and Cyclin D1 mRNA levels, whereas Per1 and Bmal1 expression changed in conjunction with beta-casein mRNA levels. Interestingly, developmental stage had differential effects on rhythms of clock gene expression in the mammary gland. These data suggest that circadian clock genes may play a role in mouse mammary gland development and differentiation. 相似文献
68.
Shepp-Logan头部模型是计算机断层图像重建(CT)领域仿真计算普遍采用的经典模型。我们提出一种新思路—以3D Shepp-Logan头部模型作为三维医学图像重建领域进行仿真实验和算法性能评测的基本参考模型。首先介绍了3D Shepp-Logan头部模型的设计与实现以及仿真投影数据的计算,进而描述了所设计的三维医学图像重建仿真计算过程。数值实验部分给出了基于3D Shepp-Logan头部模型的三维医学图像重建仿真实验。实验结果表明了新思路的可行性和模型计算的准确性。 相似文献
69.
目的观察仿生双动全髋关节置换术治疗强直性脊柱炎累及髋关节病变的临床疗效,并探讨双动臼杯在脊柱僵硬患者中应用的优势。方法回顾性分析河南省洛阳正骨医院2017年2月至2019年3月行双动全髋关节置换术的21例(41髋)强直性脊柱炎患者的临床资料,其中男18例,女3例。临床随访根据X线检查、Harris评分系统及手术前后髋关节总活动度进行评价。结果21例(41髋)患者均得到随访,随访时间13~38个月,中位数为25个月,平均(25.47±6.59)个月。Harris评分由术前(40.80±10.35)分增加到术后末次随访的(87.41±10.18)分,髋关节总活动度由术前(51.87±15.71)°增加到术后的(198.53±18.83)°,差异均具有统计学意义(P<0.05)。X线检查显示所有髋关节假体位置良好,2例(3髋)出现异位骨化,所有患者均未出现关节脱位、假体松动、感染。结论双动全髋关节置换术治疗强直性脊柱炎累及髋关节病变可明显改善髋关节功能,减轻疼痛,双动臼杯高稳定性的特点,降低了 AS患者髋臼假体安放的手术技术要求,容错率较高,从而最小化脱位的风险。 相似文献
70.
An animal model of SARS produced by infection of Macaca mulatta with SARS coronavirus 总被引:16,自引:0,他引:16
Qin C Wang J Wei Q She M Marasco WA Jiang H Tu X Zhu H Ren L Gao H Guo L Huang L Yang R Cong Z Guo L Wang Y Liu Y Sun Y Duan S Qu J Chen L Tong W Ruan L Liu P Zhang H Zhang J Zhang H Liu D Liu Q Hong T He W 《The Journal of pathology》2005,206(3):251-259
A new SARS animal model was established by inoculating SARS coronavirus (SARS-CoV) into rhesus macaques (Macaca mulatta) through the nasal cavity. Pathological pulmonary changes were successively detected on days 5-60 after virus inoculation. All eight animals showed a transient fever 2-3 days after inoculation. Immunological, molecular biological, and pathological studies support the establishment of this SARS animal model. Firstly, SARS-CoV-specific IgGs were detected in the sera of macaques from 11 to 60 days after inoculation. Secondly, SARS-CoV RNA could be detected in pharyngeal swab samples using nested RT-PCR in all infected animals from 5 days after virus inoculation. Finally, histopathological changes of interstitial pneumonia were found in the lungs during the 60 days after viral inoculation: these changes were less marked at later time points, indicating that an active healing process together with resolution of an acute inflammatory response was taking place in these animals. This animal model should provide insight into the mechanisms of SARS-CoV-related pulmonary disease and greatly facilitate the development of vaccines and therapeutics against SARS. 相似文献