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101.
Electron spectroscopic imaging (ESI) was used to analyze the element content of melanin granules in the stria vascularis
seen in ultrathin sections of Spurr-embedded cochleae of the guinea pig. To determine element composition, ESI images were
taken at different ionization edges, and non-specific background signals were subtracted digitally by an image processing
system. The presence of calcium and nitrogen in the melanin granules could be demonstrated clearly. The calcium identified
in the melanin granules was then compared with the spatial distributions of calcium binding sites after the application of
an antimonate precipitation method, which was used to localize loosely bound calcium. Despite a high calcium concentration
within the granules, only very small single scattered calcium precipitates could be detected between these structures as compared
with the amount of calcium precipitates attached to the plasma membrane or located within the cell nuclei. The nearly complete
absence of precipitates within the melanin granules after the application of antimonate suggests differences in calcium binding
and mobility involved in various physiological processes of ion balance regulation within the stria vascularis.
Received: 14 October 1997 / Accepted: 11 February 1998 相似文献
102.
103.
目的:对维吾尔医药孜尔克中总黄酮、微量元素及脂肪含量进行测定。方法:采用分光光度法,测定孜尔克的根和果实中总黄酮的含量。采用索氏抽提法提取并测定孜尔克的根和果实的脂肪含量。用原子吸收分光光度法测定孜尔克中根和果实中钙、铁、钠、钾、铜、锌、锰7种微量元素。结果:总黄酮在0.006~0.06mg.ml-1之间与吸光度有良好的线性关系。回归方程:C=0.0732A-0.002267(mg.ml-1)。相关系数R2=0.9916。元素测定中钙、铁含量较高。结论:本法操作简便,快速,为进一步研究和综合开发利用这一民族药材提供了依据。 相似文献
104.
GSTM1和GSTT1基因多态性与COPD易感性的研究 总被引:2,自引:1,他引:2
目的 探讨GSTM1、GSTT1基因多态性与COPD易感性的关系。方法 应用PCR技术对 91例COPD患者和 44例非COPD人群GSTM1、GSTT1不同基因型进行检测并根据性别、年龄及吸烟史对其易感性进行分析。结果 两组之间相比较男性及 >40岁的人群其GSTM10 / 0基因型频率有显著性差异 (P <0 0 5 ) ;在吸烟指数为≥ 3 1PY时 ,COPD组的GSTM10 / 0基因型频率显著高于对照组 (P <0 0 5 ) ;根据性别、年龄组及吸烟史分析 ,在两组人群中GSTT10 / 0基因型频率均未发现有显著性差异 (P值均 >0 0 5 ) ;两组人群综合基因型频率分析显示 ,在吸烟指数≥ 3 1PY的人群中GSTM10 / 0 -GSTT10 / 0基因型频率则显著高于对照组 (P<0 0 5 )。结论 GSTM1纯合缺失基因型可能增加了长期大量吸烟人群对COPD的易感性 ,若同时伴有GSTT1的纯合性缺失可进一步增加对COPD的易感性 相似文献
105.
S. Odent I. Casteels C. Cassiman M. Dieltiëns M.-T. Hua K. Devriendt 《Ophthalmic genetics》2017,38(2):167-170
We present a newborn diagnosed with posterior amorphous corneal dystrophy (PACD). PACD is a rare disorder with partial or complete posterior lamellar corneal opacification. Genetic screening showed a deletion of chromosome 12q21.33-q22 containing the identified four small leucine-rich proteoglycans (SLRP’s) associated with this particular dystrophy. Neither parents were carrier of the deletion. To our knowledge, this is the first report of a de novo mutation causing PACD. 相似文献
106.
《European journal of medical genetics》2017,60(11):589-594
We report the first trimester three-dimensional ultrasonographic findings in a 13-week-old fetus with complex phenotype and a de novo 4.7 Mb multigene deletion encompassing chromosome region 20q13.13-q13.2 detected by chromosomal microarray. Fetal sonography detected radial-ray anomalies in the form of bilateral absence of thumbs and the left club hand deformity. The presence of single atrioventricular canal instead of the atrial septal defect typical for Holt-Oram syndrome pointed us to rather suspect the SALL4 related diseases. Central nervous system anomaly in the form of enlarged lateral brain ventricles with choroid plexus shifted backwards was not previously reported as a part of SALL4 related disorders. The pregnancy was terminated at 14 + 3 weeks of pregnancy and the autopsy confirmed ultrasonographic findings. Deleted region included 38 genes, where only SALL4, ADNP and KCNB1 heterozygote pathogenic variants were described to be cause of syndromic forms. Radial ray anomalies are common part of clinical picture of SALL4 related disorders. Despite the lack of prenatally described cases, we hypothesized that maldevelopment of lateral brain ventriculomegaly could be very early sonographic sign of disturbed ADNP expression causing Helsmoortel-Van der Aa syndrome, but in some extent also of KCNB1 related early-onset epileptic encephalopathy. Furthermore, the possible dosage-dependent influence of recessive genes located in this region cannot be also excluded. The use of genome-wide technologies enables the detection of subtle chromosomal imbalances and more precise familial genetic counseling regarding actual and future pregnancies. 相似文献
107.
Peter M. Schneider 《Transfusion medicine and hemotherapy : offizielles Organ der Deutschen Gesellschaft fur Transfusionsmedizin und Immunhamatologie》2012,39(3):176-180
Short tandem repeat (STR) polymorphisms have been firmly established as standard DNA marker systems since more than 15 years both in forensic stain typing as well as in paternity and kinship testing. However, when analyzing genetic relationships in deficiency cases, STRs have a couple of disadvantages due to the sometimes poor biostatistical efficiency as well as the possibility to observe one or more genetic inconsistencies that could also be explained by mutational events. In such situations, additional robust markers with negligible mutations rates such as single nucleotide polymorphisms (SNPs) and insertion/deletion markers (indels) can be used as adjuncts to provide decisive genetic information in favor for or against the assumed relationship. Both SNPs and indels can now be typed more easily using multiplexes of up to 50 loci based on fragment length analysis on instruments available in all routine forensic and paternity testing laboratories, thus making it possible to extend the range of markers beyond the currently used STRs. 相似文献
108.
《Growth factors (Chur, Switzerland)》2013,31(1-2):19-35
AbstractThe important role of oncogene amplification and tumour suppressor gene deletion in human tumours is becoming increasingly apparent. However, extensive screening of human tumours is required before the prognostic significance of such genetic abnormalities can be fully appreciated. The present investigation describes a rapid non-radioactive and largely automated procedure for the analysis of aberrant gene copy number in large numbers of tissue samples of different human rumours. This procedure is based on the sequential use of the polymerase chain reaction (PCR) and high performance ion exchange liquid chromatography (HPIEX). Using this rapid PCR/HPIEX technique, we have identified amplification and deletion of the FGF-2 gene and the FGF-3, FGF-4 and c-erb-B2 oncogenes in human tumours of the breast, ovary and endometrium. Comparison of the data with tumour pathology has revealed possible associations between aberrant gene copy number and tumour type, invasiveness and metastases. 相似文献
109.
M. Perry S. Oktay J.C. Muskivitch 《Minimally invasive therapy & allied technologies》2013,22(4):165-171
Understanding the behaviour of implantable medical devices is of obvious importance. The potential for failure of a medical device can often be associated with issues related to cyclic loading of the device, and material fatigue. Detailed finite element simulations to evaluate the fatigue of stents allow the engineer to assess potential failures. The engineer can then use the analysis results to modify the design and prevent failure, without making and testing numerous physical devices. Complete understanding of the mechanical behaviour of a stent provided by finite element analysis has the benefits of facilitating effective design, helping to reduce time to market and minimising the potential for unwanted failures. 相似文献
110.
Geoffrey R. Ferril Henry P. Barham Jeremy D. Prager 《International journal of pediatric otorhinolaryngology》2014
1p36 deletion syndrome comprises a phenotypic presentation that includes central nervous system, cardiac, and craniofacial anomalies. There has been no report of associated airway anomalies with this syndrome. We present here a case report and literature review. Prenatally, amniocentesis for chromosomal analysis was performed on our patient, with results consistent with 1p36 deletion syndrome. Respiratory distress and unsuccessful attempts at intubation prompted transfer to Children's Hospital of Colorado. Microlaryngoscopy was subsequently performed, revealing a persistent buccopharyngeal membrane and unidentifiable larynx. Emergent tracheostomy was then performed to secure the airway. Airway anomalies may be associated with 1p36 deletion syndrome. 相似文献