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61.
目的探讨miR-21对骨质疏松小鼠骨髓基质细胞(BMSCs)增殖的影响。方法采用双侧卵巢切除法构建骨质疏松小鼠模型(VOX),分离、培养、纯化小鼠BMSCs并采用si PORT Neo FX转染pre-miR-21、pre-miR-negative control(pre-miR-NC)、antmiR-21、ant-miR-negative control(ant-miR-NC)并进行RT-PCR验证,MTT法检测小鼠BMSCs增殖情况、茜素红与碱性磷酸酶染色法检测小鼠BMSCs成骨能力、Western-blotting检测细胞增殖、成骨分化相关蛋白水平。结果骨质疏松症小鼠BMSCs中miR-21相对表达水平低于Ctrl组(P0.05),OVX-pre-miR-21组BMSCs中miR-21相对表达水平、细胞增殖、PCNA水平、Ki-67水平、ALP染色程度、ALP活性、茜素红染色程度、Runx2水平、Osterix水平均高于OVX-pre-miR-NC组(P0.05),OVX-premiR-NC组BMSCs中miR-21相对表达水平、细胞增殖、PCNA水平、Ki-67水平、ALP染色程度、ALP活性、茜素红染色程度、Runx2水平、Osterix水平均显著低于Ctrl-pre-miR-NC(P0.05); OVX-ant-miR-21组BMSCs中miR-21相对表达水平、细胞增殖、PCNA水平、Ki-67水平、ALP染色程度、ALP活性、茜素红染色程度、Runx2水平、Osterix水平均显著低于OVX-ant-miR-NC组(P0.05),OVX-ant-miR-NC组BMSCs中miR-21相对表达水平、细胞增殖、PCNA水平、Ki-67水平、ALP染色程度、ALP活性、茜素红染色程度、Runx2水平、Osterix水平均显著低于Ctrl-ant-miR-NC(P0.05)。结论提高miR-21表达水平可促进骨质疏松小鼠BMSCs增殖能力与成骨分化能力。 相似文献
62.
Birgitte Hertz Carsten A. Brandt Michael B. Petersen Søren Pedersen Ulrich König Helle Strømkjær Peter K. A. Jensen 《Clinical genetics》1993,44(2):89-94
Hertz B, Brandt CA, Petersen MB, Pedersen S, König U, Strømkjær H, Jensen PKA. Application of molecular and cytogenetic techniques to the detection of a de novo unbalanced t(11q;21q) in a patient previously diagnosed as having monosomy 21.
Clin Genet 1993: 44: 89–94. © Munksgaard, 1993
The occurrence of complete autosomal monosomy in man is extremely rare and generally considered to be incompatible with life. Since the introduction of banding techniques in human cytogenetics, several cases of presumptive monosomy for chromosome 21 have nevertheless been reported. However, it has been suggested that most, if not all, of these cases may represent unbalanced translocations or other structural aberrations resulting in only partial monosomy 21. Here we describe a patient in whom full monosomy 21 was initially diagnosed by routine karyotyping. Re-examination with a combination of high resolution banding technique, chromosome painting and DNA polymorphism analysis demonstrated the presence of an unbalanced translocation between the long arms of chromosome 11 and 21, respectively. Consequently, the case was re-classified as a partial monosomy for the proximal long arm of chromosome 21. 相似文献
Clin Genet 1993: 44: 89–94. © Munksgaard, 1993
The occurrence of complete autosomal monosomy in man is extremely rare and generally considered to be incompatible with life. Since the introduction of banding techniques in human cytogenetics, several cases of presumptive monosomy for chromosome 21 have nevertheless been reported. However, it has been suggested that most, if not all, of these cases may represent unbalanced translocations or other structural aberrations resulting in only partial monosomy 21. Here we describe a patient in whom full monosomy 21 was initially diagnosed by routine karyotyping. Re-examination with a combination of high resolution banding technique, chromosome painting and DNA polymorphism analysis demonstrated the presence of an unbalanced translocation between the long arms of chromosome 11 and 21, respectively. Consequently, the case was re-classified as a partial monosomy for the proximal long arm of chromosome 21. 相似文献
63.
An isolated case of Duchenne muscular dystrophy (DMD) in a female who has a deletion of the DMD locus is described. This patient was a 26-year-old woman born to unrelated, healthy parents. She was initially examined at age 6 because of a waddling gait. At age 15, pseudohypertrophy of calves and pes equinus were observed along with proximal muscular weakness and wasting. Her serum creatine kinase level was high and histological evidence of muscular dystrophy was apparent on muscle biopsy. The patient was ambulant at age 15 and progression of motor disability has been slow. Chromosomal studies revealed a normal karyotype, and mental retardation is moderate. DNA analysis at age 26 revealed that she has a deletion of DMD cDNA 8 mapped within Xp21 and is heterozygous for the deletion. Since diagnosis of DMD is now dependent on the evidence of mutation or deletion at Xp21, this patient is thought to have a form of DMD. Expression of the DMD gene in the heterozygous state might be due to random but unequal lyonization. 相似文献
64.
Bernard S. Kaplan Thomas G. Cleary Thomas G. Obrig 《Pediatric nephrology (Berlin, Germany)》1990,4(3):276-283
One of the requirements for an agent to cause hemolytic uremic syndrome (HUS) is its ability to injure endothelial cells. Shiga-like toxin (SLT) can do this. SLT is produced byEscherichia coli andShigella dysenteriae serotype 1; both have been implicated as causes of typical HUS. Endothelial cells have receptors (GB3) for SLT and the toxin can inhibit eukaryotic protein synthesis, thereby causing cell death. Glomerular endothelial cell injury or death results in a decreased glomerular filtration rate and many of the perturbations seen in HUS. It is no longer certain that hemolysis is the result of a microangiopathy. Cell injury results in release of von Willebrand multimers; if these are ultra-large, thrombosis may ensue. There is also increasing evidence that neutrophils have a role in the pathogenesis of typical HUS.Streptococcus pneumoniae can also cause HUS and care must be taken to avoid giving plasma to patients withS. pneumoniae-associated HUS. There is compelling evidence that types of HUS are inherited by autosomal recessive and autosomal dominant modes. Patients with autosomal recessive HUS may have recurrent episodes. Mortality and morbidity rates are high for the inherited forms. 相似文献
65.
吸烟对多环芳烃接触者生物膜损伤指标、染色体畸变和P21蛋白的影响 总被引:1,自引:0,他引:1
目的:了解吸烟对多环芳烃接触者生物膜损伤指标、染色体畸变和血清癌基因蛋白P21的影响.方法:对接触多环芳烃化合物的24名焦炉工和27名沥青工中吸烟与不吸烟者的血清谷胱甘肽S-转移酶(GST)、血清脂质结合唾液酸(LSA)、染色体畸变和血清癌基因蛋白P21水平进行研究.结果:吸烟与不吸烟者间GST、LSA、染色体畸变率和血清P21水平各指标差异均无显著性差异(P>0.05).结论:吸烟对多环芳烃接触者沥青工和焦炉工的GST、LSA、染色体畸变率和血清P21水平无明显影响,可能是沥青工、焦炉工接触多环芳烃混合物浓度较高,掩盖了吸烟的作用. 相似文献
66.
目的:为了解接触焦炉逸散物职业性人群遗传效应的改变,从分子水平揭示焦炉逸散物的遗传毒作用.方法:对25名焦炉工和12名正常对照分别检测了血清P21和外周血淋巴细胞姐妹染色单体互换(SCE)率.结果:发现焦炉工P21水平(3 774.2)、SCE率(11.43)明显高于对照组P21水平(1 270.7)和SCE率(6.37);焦炉工中,炉顶工血清P21均值(4 377.5)高于其它工种(3 300.1),炉顶工SCE(13.51)明显高于其它工种(10.07);对焦炉工按是否吸烟进行比较,未发现组间P21和SCE有差异显著性.结论:提示焦炉逸散物具有较强的遗传毒理学效应,可提高机体癌蛋白P21水平和SCE频率. 相似文献
67.
目的 :了解多环芳烃接触者遗传指标和血清癌基因蛋白P2 1表达水平及其在肺癌早期诊断中的意义 ,为多环芳烃作业者的劳动保护提供科学依据。方法 :对接触多环芳烃化合物的焦炉工 2 4名、沥青工 2 7名和健康对照组 31名的染色体畸变率和血清癌基因蛋白P2 1水平进行了检测。结果 :染色体异常检出率 ,焦炉工和沥青工均显著高于对照组 (P <0 .0 0 5 ) ;染色体裂隙次数 ,焦炉工和沥青工均显著高于对照组 (P <0 .0 1) ;染色体结构、数目畸变数 ,焦炉工显著高于对照组 (P <0 .0 1)。血清P2 1水平 ,焦炉工、沥青工均显著高于对照组 (P <0 .0 5 ) ,沥青工显著高于焦炉工 (P <0 .0 5 )。结论 :多环芳烃化合物具有遗传毒性 ,并可致血清P2 1蛋白水平升高。 相似文献
68.
69.
【目的】研究 p5 3、p2 1和bcl 2基因蛋白在舌鳞状细胞癌组织中的表达及其临床意义。【方法】用免疫组化SP法检测 5 4例舌鳞状细胞癌组织标本p5 3、p2 1和bcl 2癌基因蛋白表达。【结果】舌鳞状细胞癌组织中p5 3、p2 1和bcl 2蛋白阳性率分别为 46 %、6 1%、46 % ;p5 3和 p2 1蛋白表达与肿瘤细胞分化程度及颈淋巴结转移有关 (P <0 0 5 ) ;p5 3蛋白表达与 p2 1蛋白表达有关 (P <0 0 5 ) ,bcl 2基因蛋白表达与 p5 3或p2 1基因蛋白表达无关 (P >0 0 5 )。【结论】舌鳞状细胞癌组织中具有较高的 p5 3、p2 1和bcl 2癌基因蛋白表达 ;p5 3和 /或p2 1蛋白阳性病例恶性程度高 ,易发生颈淋巴结转移。p5 3和 /或 p2 1蛋白可作为舌鳞癌预后的参考指标 相似文献
70.
胃癌及癌前病变组织中雌激素受体和P21ras的表达及意义 总被引:1,自引:0,他引:1
目的 探讨雌激素受体(ER)和ras原癌基因蛋白-P2ras的表达在胃癌发生、发展中的作用及与胃癌生物学行为的关系。方法 采用免疫组化SP法。结果 ER在慢性浅表性胃炎(20例)、异型增生(21例)中均为阴性,胃癌(40例)的表达阳性率为40%,三组比较有显著性差异(I〈0.05)。P21^ras在慢性浅表性胃炎、异型增生、胃癌的表达阳性率分别为10%、23.8%、47.5%,三组比较差异有显著性 相似文献