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961.
Delivery of a hammerhead ribozyme specifically down-regulates the production of fibrillin-1 by cultured dermal fibroblasts 总被引:4,自引:1,他引:4
Kilpatrick MW; Phylactou LA; Godfrey M; Wu CH; Wu GY; Tsipouras P 《Human molecular genetics》1996,5(12):1939-1944
The hammerhead ribozyme is a small catalytic RNA molecule. Potential
hammerhead ribozymes that possess a catalytic domain and flanking sequence
complementary to a target mRNA can cleave in trans at a putative cleavage
site within the target molecule. We have investigated the potential of
hammerhead ribozymes to down-regulate the product of the fibrillin-1 gene
(FBN1). Fibrillin is a 347 kDa glycoprotein that is a major constituent of
the elastin-associated microfibrils. Mutations in the FBN1 gene are
responsible for Marfan syndrome (MFS), a common systemic disorder of the
connective tissue. Many FBN1 mutations responsible for MFS appear to act in
a dominant-negative fashion, raising the possibility that reduction of the
amount of product from the mutant FBN1 allele might be a valid therapeutic
approach for MFS. A trans-acting hammerhead ribozyme (FBN1-RZ1) targeted to
the 5' end of the human FBN1 mRNA has been designed and synthesized, and
shown to cleave its target efficiently in vitro. FBN1-RZ1 cleavage is
magnesium dependent and efficient at both 37 and 50 degrees C. Delivery of
the FBN1-RZ1 ribozyme into cultured dermal fibroblasts, by receptor-
mediated endocytosis of a ribozyme-transferrin-polylysine complex,
specifically reduces both cellular FBN1 mRNA and the deposition of
fibrillin in the extracellular matrix. These results suggest that the use
of hammerhead ribozymes is a valid approach to the study of fibrillin gene
expression and possibly to the development of a therapeutic approach to
MFS.
相似文献
962.
构建突变MyD88真核表达质粒(MyD88 DN),转染人呼吸道上皮细胞株A549,探讨其对绿脓杆菌及其分泌产物刺激IL-8表达的影响.结果显示突变MyD88成功构建入pcDNA3.1/zeo真核表达质粒,转染A549细胞后,可降低绿脓杆菌培养上清或活菌刺激诱导的IL-8分泌.提示突变MyD88可阻断绿脓杆菌感染引起的呼吸道上皮细胞IL-8释放,为呼吸道炎症的基因治疗提供了新的靶基因. 相似文献
963.
Diversity of rotavirus strains among children with acute diarrhea in China: 1998-2000 surveillance study 总被引:24,自引:0,他引:24
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Fang ZY Yang H Qi J Zhang J Sun LW Tang JY Ma L Du ZQ He AH Xie JP Lu YY Ji ZZ Zhu BQ Wu HY Lin SE Xie HP Griffin DD Ivanoff B Glass RI Gentsch JR 《Journal of clinical microbiology》2002,40(5):1875-1878
As part of a national rotavirus surveillance activity, we collected fecal specimens from 3,177 children with acute diarrhea in 10 regions of China between April 1998 and April 2000 and screened them for rotavirus. Rotavirus was detected in 41% (n = 1,305) of specimens, and in these, G1 was the predominant serotype (72.6%), followed by G3 (14.2%), G2 (12.1%), G4 (2.5%), G9 (0.9%), and G untypeable (0.7%). Among 327 G-typed strains tested for P genotype, 14 different P-G combinations were identified, with the globally common strains P[8]G1, P[4]G2, P[8]G3, and P[8]G4 representing 75.6% of all typed rotavirus strains. Among the uncommon strains, 11 were P[6]G9, and others included P[6]G1, P[6]G3, and five novel P-G combinations (P[9]G1, P[4]G1, P[4]G3, P[4]G4, and P[8]G2). Our results indicate that while the common rotavirus strains remain predominant, the diversity of strains is much greater than was previously recognized. 相似文献
964.
Palmer SL Gajjar A Reddick WE Glass JO Kun LE Wu S Xiong X Mulhern RK 《Neuropsychology》2003,17(4):548-555
Fifty children diagnosed with medulloblastoma completed 188 psychological evaluations using the Wechsler Intelligence Scales for Children (D. Wechsler, 1974, 1991) over a 7-year study period following 35-40 Gy postoperative craniospinal irradiation. Random coefficient models were used to predict the trend in the children's intellectual performance as a function of time since diagnosis, with both patient and treatment variables as parameters of this function. A quadratic model demonstrated a delay prior to decline in performance for older patients, whereas the younger patients showed an immediate loss of performance with a plateau at approximately 6 years postdiagnosis. A steeper decline was found for those with higher baseline performance. Clinicians may use the proposed predictive model to identify those patients who are at risk of significant intellectual decline. 相似文献
965.
自发性高血压大鼠的微血管改变及其与血管内皮细胞损伤的关系 总被引:7,自引:1,他引:7
目的:探讨自发性高血压大鼠(SHR)的微血管改变与血管内皮细胞(VEC)损伤的关系。方法:以10只成年Wistar-Kyoto大鼠(WKY)为正常对照组(WKY组)。观察、计数10只成年SHR的肠壁微动脉管径和分支数,同时测定血浆亚硝酸根(NO2-)和内皮素(ET)并与WKY组对照。结果:SHR组的肠壁各级微动脉管径较WKY组变细(P<0.01~0.001)、各级微动脉总条数较WKY组减少(P<0.001~0.0001);SHR组的血浆NO2-水平和K值[10g(NO2-/ET)」较WKY组低(P<0.05~0.001),而ET较WKY组高(P<0.05)。血压和K值分别与肠壁微动脉管径和条数呈负相关和正相关(P<0.005~0.001)。结论:高血压的微血管结构异常与VEC损伤有密切的关系。 相似文献
966.
Reading Julian P.; Huffman John L.; Wu Joy C.; Palmer Frances T.; Harton Gary L.; Sisson Michael E.; Keyvanfar Keyvan; Gresinger Thomas H.; Cochrane William J.; Fallon Lee A.; Menapace-Drew Gianna F.; Cummings Emilie A.; Jones Shirley L.; Black Susan H.; Schulman Joseph D.; Levinson Gene 《Molecular human reproduction》1995,1(7):362-367
The discovery of nucleated erythrocytes in maternal circulationprovides a potential source for non-invasive prenatal diagnosis.We have evaluated the use of a three-stage procedure to determinethe number of cells that are of fetal rather than maternal origin.First, monoclonal antibodies specific for CD45 and CD14 wereused in conjunction with a magnetic (MACS) column to depleteunwanted leukocytes from maternal blood. This was followed bya positive MACS enrichment for nucleated erythrocytes, usingan anti-CD71 (transferrin receptor) monoclonal antibody. Todiscriminate between fetal nucleated erythrocytes and thoseof maternal origin, enriched fractions were simultaneously stainedwith an anti-fetal haemoglobin (HbF) antibody and hybridizedwith probes specific for X and Y chromosomes. Samples were thensubjected to blind analysis along with negative control samplesfrom non-pregnant volunteers. Using this dual analysis, we wereable to determine that less than one nucleated erythrocyte perml of maternal blood was of fetal origin. Small numbers of thesefetal cells were found in 87.5% of pregnancies, ranging from6 to 35 weeks gestational age. Comparison of HbF and X/Y probedata also suggests that the fetal cells are less suitable forfluorescence in-situ hybridization (FISH) analysis than similarpreparations from other sources. cell separation methods/fluorescence in-situ hybridization/hereditary diseases/polymerase chain reaction/pregnancy 相似文献
967.
目的 总结143例晚期喉癌患者的临床特征,分析预后的影响因素。方法 回顾性分析2010年1月-2016年12月经中国人民解放军总医院治疗的143例晚期喉癌患者的临床资料。其中,男135例(94.4%),女8例(5.6%);年龄35~79岁,中位年龄58岁。依据患者治疗方案不同分为2组:手术联合术后放化疗组106例和非手术综合治疗组37例。收集患者基本临床情况、治疗、随访及生存情况;生存率及单因素生存分析采用Kaplan-Meier法和log-rank检验,多因素生存分析采用Cox比例风险回归模型。结果 143例晚期喉癌患者的5年总体生存率为67.9%。单因素分析显示,影响晚期喉癌患者预后的临床因素有年龄、临床分期、T分期及肿瘤分化程度等(P值均<0.05);Cox模型多因素分析显示,患者年龄、临床分期、肿瘤分化程度及治疗方式是影响预后的独立危险因素(P值均<0.05)。T4期、临床Ⅳ期患者采用手术联合术后放化疗5年生存率分别为62.2%和59.5%,明显好于非手术综合治疗的18.2%和41.4%,差异均有统计学意义(P值均<0.05)。结论 晚期喉癌患者预后相对较差,影响患者预后的因素包括患者年龄、临床分期、肿瘤分化程度及治疗方式等。对于临床Ⅳ期、尤其是T4期患者,采取手术联合术后放化疗可以获得相对较好的预后。 相似文献
968.
969.
Hsu SC Lin HP Wu JC Ko KL Sheen IJ Yan BS Chou CK Syu WJ 《Journal of virological methods》2000,87(1-2):53-62
Sequences of the hepatitis delta virus (HDV) vary to different degrees among isolates. A monoclonal antibody, designated as HP6A1, against the antigen of HDV (HDAg) has been characterized for its specificity. HP6A1 bound to HDAg of isolate 25 (genotype I) that was used for immunization, but not to others of both genotypes I and II. The epitope recognized by HP6A1 was then determined by a phage library displaying various heptapeptides. A consensus peptide deduced has the best match with that of residues 4-10 of HDAg (isolate 25). To confirm the phage mapping result, Escherichia coli recombinant proteins containing different lengths and various segments of HDAg (isolate 25) were constructed. The shortest HDAg segment contained in the fusion protein that reacted with HP6A1 was residues 1-10. When this peptide was added to the N-terminus of a heterologous protein engineered for eucaryotic expression, the fusion protein was detected by HP6A1. It is concluded that HP6A1 recognizes an epitope located at the N-terminus of HDAg (isolate 25). Since viruses of quasi-species exist in natural infections, a question of how different viral strains interact in vivo remains to be explored. The highly specific MAb opens a possibility to examine the fate of one strain in the presence of other related species in a cell transfection system. 相似文献
970.
用PCR-SSCP分析检测睾丸女性化综合征患者雄激素受体基因突变 总被引:4,自引:1,他引:4
为进一步探讨睾丸女性化(Tfm)综合征患者发病的分子机理,并为研究雄激素受体(AR)结构与功能关系提供资料,应用银染聚合酶链式反应-单链构象多态性(PCR-SSCP)分析方法对4例Tfm患者的AR基因8个外显子中的7个(B~H)分别进行了研究。结果表明,所有患者AR基因的上述外显子经PCR扩增后均出现与外显子相应长度一致的条带,表明没有明显的缺失或插入突变。2例患者外显子G片段在行SSCP分析时分别有泳动变位,经DNA双链循环测序证实两外显子各有一点突变(Val866Met,T2919→Δ),这些突变均位于AR的雄激素结合区内。其中的缺失突变为国际上尚未报道过的新突变。研究表明,PCR-SSCP分析是检测AR基因突变的快速、简便、可靠的方法。 相似文献