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81.
82.
为了解白细胞介素 - 8的体内行为 ,用 Bolton- Hunter法对 IL- 8进行 1 2 5I标记 ,并测定它在小鼠体内的分布 ;得到了 1 2 5I- IL- 8在小鼠血、心、肝、肺、肾、骨、脾等脏器中的分布以及它在血液中的快相半排期 T1 /2α为 0 .3 2 h和慢相半排期 T1 /2β为 8.0 1h。1 2 5I- IL- 8主要通过肾排除  相似文献   
83.
Wei H  Qin ZH  Senatorov VV  Wei W  Wang Y  Qian Y  Chuang DM 《Neuroscience》2001,106(3):603-612
Huntington's disease is a progressive, inherited neurodegenerative disorder characterized by the loss of subsets of neurons primarily in the striatum. In this study, we assessed the neuroprotective effect of lithium against striatal lesion formation in a rat model of Huntington's disease in which quinolinic acid was unilaterally infused into the striatum. For this purpose, we used a dopamine receptor autoradiography and glutamic acid decarboxylase mRNA in situ hybridization analysis, methods previously shown to be adequate for quantitative analysis of the excitotoxin-induced striatal lesion size.Here we demonstrated that subcutaneous injections of LiCl for 16 days prior to quinolinic acid infusion considerably reduced the size of quinolinic acid-induced striatal lesion. Furthermore, these lithium pre-treatments also decreased the number of striatal neurons labeled with the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay. Immunohistochemistry and western blotting demonstrated that lithium-elicited neuroprotection was associated with an increase in Bcl-2 protein levels.Our results raise the possibility that lithium may be considered as a neuroprotective agent in treatment of neurodegenerative diseases such as Huntington's disease.  相似文献   
84.
Cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) is important for downregulation of T-cell activation, and CTLA-4 gene polymorphisms have been implicated as risk factors for rheumatoid arthritis (RA). Previous studies of the association between the +49 polymorphism of the CTLA-4 gene in RA have provided conflicting results. In order to determine association of the CTLA-4 gene with RA in Chinese Han population, we used denaturing gradient gel electrophoresis (DGGE) to genotype polymorphisms of four SNPs (MH30, +49, CT60 and JO31) of the CTLA-4 gene in 326 RA patients and 250 healthy controls. Furthermore, meta-analysis of all available studies relating +49 polymorphism to the risk of RA was performed to confirm the disease association. Among the SNPs examined, the genotype frequencies of CTLA-4 +49 and CT60 in RA patients differed significantly from controls (P=0.028 and 0.007). In addition, the distribution of four haplotypes constructed by these two SNPs was significantly different between patients and controls (chi(2)=10.58, d.f. =3, P=0.014). The meta-analysis also revealed that in both European and Asian populations, the CLTA-4 +49 G allele was associated with the risk of RA. These results suggested that the CTLA-4 gene might be involved in the susceptibility to RA in the Chinese Han population and both +49 and CT60 of CTLA-4 gene might be the causal variants in RA disease.  相似文献   
85.
OBJECTIVE: To investigate the relationship between the plasminogen activator inhibitor (PAI-1) polymorphisms and endometrial hypoplasia in infertile women. METHODS: The study was conducted in 105 primary infertile patients with endometrial hypoplasia diagnosed by pathology and the thickness of endometrium by B-mode ultrasound and 85 controls who were not pregnant and had normal fertility. The -675 4G/5G polymorphism in the PAI-1 gene was detected by polymerase chain reaction-restriction fragment length polymerphim analysis. RESULTS: The frequencies of 4G/4G genotype and 4G allele of the PAI-1 gene were higher in the patient group (48.6% and 66.2%) than in the normal controls (22.4% and 47.1%) (P < 0.01). ThePAI-1 4G/4G genotype was significantly associated with endometrial hypoplasia in the infertile patients (OR=4.9, 95% CI: 2.10-10.12). CONCLUSION: The present findings suggest that the 4G/5G polymorphism of the PAI-1 gene was associated with endometrial hypoplasia in infertile patients.  相似文献   
86.
Enhancement of S-antigen and its mRNA in the irides of uveitic patients   总被引:1,自引:0,他引:1  
S-antigen (S-Ag) and its mRNA were analysed by immunohistochemistry and in situ hybridization in 32 iridectomy specimens from 29 uveitic patients and 10 non-uveitic patients. S-Ag was detected in one iris and its mRNA was detected in 12 uveitic patients. Neither S-Ag nor its mRNA was found in the controls (P < 0.003). Ten of the 12 patients who had detectable S-Ag mRNA, while only four of the 17 patients who did not, had received corticosteroids for more than 3 years (P = 0.006). We also demonstrated S-Ag and its mRNA in bovine iris by immunoprecipitation and polymerase chain reaction. These results indicate that S-Ag and its mRNA accumulate in the irides of some uveitic patients. This accumulation may be the result of local immunoregulatory factors and an effect of corticosteroid treatment, and may modulate ocular inflammation.  相似文献   
87.
钱学森同志谈中医学的科学水平及其发展   总被引:1,自引:0,他引:1  
我国科学家钱学森同志十分关心中医学的发展,多次从科学技术全局的战略高度发表具有深远意义的见解。一九八五年六月,他看了我院马列主义教研室讲师祝世讷编写的教材《中医系统论导论》后,来信给予热情鼓励。九月,祝世讷同志在给钱学森同志的一封信中谈了两个问题:(一)关于中医学是经验科学还是理论科学,目前存在争论。提出,恩格斯在《自然辩证法》和《路德维希·费尔巴哈和德国古典哲学的终结》两书中有三段话,论述了十九世纪自然科学从经验科学向理论科学的转变,根据恩格斯的论断,中医学的发展处于经验科学阶段。但是,迄今还没有人就什么是经验科学、什么是理论科学以及两者之间的联系和区别作出系统的理论说明,因而,对于中医学科学水平的认识,往往由于缺乏必要的理论根据而产生一些模糊观念,建议钱学森同志在适当场合从理论上作较系统的论述。(二)关于中医学发展阶段的“断代”问题。提出,自然科学的各学科,在发展中大都划分出经典科学阶段与现代科学阶段,如欧氏几何学与非欧几何学,经典物理学与现代物理学等等,中医学也应当划分出“经典中医学”与“现代中医学”,现在实际上已出现了这样的分化趋势,自觉地认识和处理,可能更有利于中医学的发掘和发展。钱学森同志接信后,回信较系统地谈了一些原则性意见,对于正确认识中医学的科学水平及其发展,具有十分重要的意义。现将钱学森同志的这封信全文发表,供大家学习和研究。  相似文献   
88.
"Spontaneous" remission of leukemia has been observed in both humans and animals. Bierman et al2 in 1953 reported 11 cases of remis- sion in acute lymphoblastic leukemia (ALL) of childhood following acute infectious disease. In 1979 we saw a case of ALL remission in a child following a severe attack of respiratory infection.  相似文献   
89.
目的 比较孤独症谱系障碍(ASD)儿童与典型发育(TD)儿童母亲的焦虑状况,探索ASD儿童情绪行为问题与其母亲焦虑水平间的关系。方法 通过临床诊断招募55名6~12岁智商≥70的ASD儿童及74名TD儿童,采用状态-特质焦虑问卷(STAI)评估入组儿童母亲的焦虑情况,采用长处与困难问卷(SDQ)评估两组儿童情绪行为问题及表现。结果 ASD儿童组母亲状态焦虑得分与特质焦虑得分高于TD组母亲(t=5.272、4.484、P<0.05),ASD儿童SDQ困难总分及多动/注意力缺陷、情绪症状、同伴交往问题及品行问题因子得分高于TD组儿童(t=10.791、7.482、4.295、12.925、3.544),亲社会行为因子分(t=5.084)低于TD组儿童,差异均有统计学意义(P<0.01)。校正混杂因素后,ASD组母亲状态、特质焦虑得分与儿童困难总分 [S-AI: β=0.83 (95%CI: 0.19~1.46); T-AI: β=0.60 (95%CI: 0.05~1.14)]、情绪症状 [S-AI: β=2.28 (95%CI:0.72~3.84); T-AI: β=2.04 (95%CI: 0.74~3.33)]存在正相关关系(P<0.05)。TD组母亲状态焦虑得分与儿童困难总分 [β=0.50 (95%CI: 0.03~0.96)]、品行问题 [β=1.74 (95%CI: 0.19~3.30)]存在正相关关系;特质焦虑得分与品行问题 [β=1.54 (95%CI: 0.09~3.00)]存在正相关关系(P<0.05)。结论 ASD儿童母亲比TD儿童母亲更容易出现焦虑。其中ASD儿童母亲的焦虑水平与儿童情绪问题有关,TD儿童母亲的焦虑水平与儿童品行问题有关。  相似文献   
90.
目的 探究4种临床CT扫描方式对受检者常见组织吸收剂量的影响及胸部扫描的辐射场空间分布,以期为受检者与机房内空间辐射防护提供依据。方法 利用热释光探测器(TLD)测量仿真体模的眼晶体、甲状腺、性腺、胸部和腹部皮肤在4种CT扫描方式下的吸收剂量。利用TLD监测胸部螺旋扫描时距离CT诊断床不同位置处的空气比释动能。结果 仿真体模的眼晶体、甲状腺、性腺、胸部和腹部皮肤在4种CT扫描方式下的吸收剂量分别为0.040~64.818 mGy、0.154~10.155 mGy、0.028~0.154 mGy、0.443~17.141 mGy和0.093~14.346 mGy。胸部扫描时空间辐射场的空气比释动能最大值为0.049 mGy,且与CT球管距离越大数值越小。结论 4种CT扫描方式对受检者常见组织的吸收剂量一般不会超过阈剂量。单次CT胸部扫描时陪检者所受剂量较小。为减少辐射危害,在CT扫描中可采取屏蔽措施来减少受检者组织吸收剂量,同时陪检者应适当增加与球管和诊断床的距离。  相似文献   
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