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81.
Complete absence of third molars and mandibular permanent second molars is reported in a 19-year-old female, with occipito-frontal head circumference and height at the 3rd centile. The patient's intelligence, appearance and physical examination were normal. Direct count of the patient's sweat pores in different areas of the palms and digits was normal. Microcephaly, short stature and normal intelligence have been reported in two families as a distinct autosomal dominant syndrome. To the best of our knowledge, oligodontia, in addition to these findings, has not been previously reported. 相似文献
82.
Susan E. Douglas 《Current genetics》1988,14(6):591-598
Summary A physical map of the circular plastid genome of Cryptomonas has been constructed using the enzymes SacI, BamHI, SmaI, SalI, PstI and XhoI. In addition, fine-structural mapping of the inverted repeat region has been performed using AvaI, BglII, EcoRI and XbaI. The inverted repeat is very small, encompassing no more than 6 kb and containing only genes for the rRNAs. It divides the plastid genome into a small singlecopy region of 12–13 kb which contains genes for phycoerythrin and the 32 kd photosystem II polypeptide, and a large single-copy region of 93–94 kb, giving a total size of 118 kb. The genes for the large subunit of ribulose-1,5-bisphosphate carboxylase (Rubisco) and the beta subunit of ATP synthase CF1 are encoded in the large single-copy region. The evolutionary significance of the organization of this plastid genome, the first presented from the chlorophyll c-, phycobiliprotein-containing group of algae, is discussed. 相似文献
83.
[摘要] 目的:研究Iα1 hs1,2 VNTR多态性与我国IgA肾病的相关关系。 方法: 采集419例肾活检证实的IgA肾病患者及其一级亲属、条件相当的201例健康志愿者血样,提取基因组DNA。用PCR产物直接电泳法鉴定Iα1 hs1,2 VNTR基因型,采用以家庭为基础的传递/不平衡分析(TDT)和单倍型相对危险度(HRR),以及病例-对照研究分析Iα1 hs1,2 VNTR多态性与我国IgA肾病的相关关系。 结果: ① TDT分析结果显示Iα1 hs1,2 VNTR B等位基因从杂合子父母向患者传递的频率显著高于预期值(101 Trios, χ2=6.818, P<0.01,扩展TDT分析也得到相同结果(164家庭, χ2=7.583, P<0.01)。②与TDT结果一致,HRR分析同样显示Iα1 hs1,2 VNTR B等位基因的过度传递 (P<0.05, χ2=4.122, HRR=1.180), 而BB基因型具有更强的患病倾向 (P<0.05, χ2=4.411, OR=1.538)。③病例-对照研究显示IgA肾病组B 等位基因频率显著高于正常对照组(χ2=6.968, P<0.05)。 结论: Iα1 hs1,2 VNTR基因多态性与我国IgA肾病患者的易感性相关。 相似文献
84.
Isolation and radiation hybrid mapping of a dinucleotide repeat polymorphism at the human calcium-sensing receptor (CASR) locus 总被引:2,自引:0,他引:2
Kazuhiro Tsukamoto Ikuyo Watanabe Tadayoshi Shiba M. Emi 《Journal of human genetics》1998,43(4):280-282
Calcium-sensing receptor (CASR) in parathyroid gland regulates calcium homeostasis by sensing decreases in extracellular
calcium levels and effecting an increase in secretion of parathyroid hormone. A polymorphic dinucleotide (CA) sequence was
isolated from a genomic clone containing the human CASR gene and was mapped to 3q13.3–q21. This polymorphism will be useful in the genetic study of disorders affecting calcium metabolism,
such as hypercalcemia, hypocalcemia, osteoporosis, hyperparathyroidism, and hypoparathyroidism.
Received: June 2, 1998 / Accepted: June 24, 1998 相似文献
85.
Cardiac ankyrin repeat protein (CARP), which is structurally characterized by the presence of four ankyrin repeat motifs in its central region, is believed to be localized in the nucleus and to participate in the regulation of cardiac-specific gene expression in cardiomyocytes. However, we recently found that CARP was induced in skeletal muscle by denervation, leading us to speculate that CARP may be induced under some pathological conditions. In the present study, we immunohistochemically analyzed the expression of CARP in 11 cases of spinal muscular atrophy (SMA) and 14 cases of congenital myopathy. In SMA, CARP was expressed selectively in severely atrophic myofibers, suggesting that CARP expression may reflect the status of muscle atrophy. Furthermore, in the congenital myopathies, the expression patterns of CARP were distinct among the subtypes, which included nemaline myopathy, myotubular myopathy, central core disease, and congenital fiber type disproportion. Although CARP was preferentially expressed in severely damaged myofibers in nemaline myopathy, it was not detected in central core disease. These findings suggest that immunohistochemical evaluation of CARP may be helpful in the diagnosis of SMA and the congenital myopathies. 相似文献
86.
Arabella Smith Gesina den Dulk Renate Viersbach John Michas 《American journal of medical genetics. Part A》1991,40(4):460-463
A phenotypic female with mild mental retardation, minor facial anomalies, and short stature has been evaluated clinically and cytogenetically over 29 years. At age 59, she remains physically well and shows no signs of dementia. Cytogenetic analysis, performed on peripheral blood specimens on 10 occasions between 1961 and 1990, showed mosaicism with one cell line containing a large stable ring (15) chromosome and another cell line without the ring but with a 15qs +. The different cell lines remained constant. The case provides information on the natural history of the ring chromosome 15 syndrome. 相似文献
87.
青岛地区D6S477等五个短串联重复序列基因座的遗传多态性研究 总被引:3,自引:0,他引:3
目的 了解D6S477等5个基因座在青岛地区汉族群体中基因型分布及等位基因频率等遗传多态性数据,初步探讨其应用价值。方法 收集200名青岛地区汉族无关个体的静脉血,ACD抗凝,采用Chelex法提取DNA,应用聚合酶链反应技术,扩增D6S477、D9S1118、D18S865、D19S400和D20S161基因座的短串联重复序列,聚丙烯酰胺凝胶垂直电泳,银染显色分型。结果 获得了青岛地区汉族群体上述5个基因座的等位基因频率,基因型分布均符合Hardy-Weinberg平衡(P〉0.05)。结论 这5个基因座在青岛地区汉族群体中有较高的非父排除率和个人识别机率,在遗传学研究中有较高的应用价值。 相似文献
88.
Masato Tsukahara Kiyosato Matsuo Susumu Furukawa 《American journal of medical genetics. Part A》1995,58(2):159-160
We report on a 9-year-old boy with radioulnar synostosis, short stature, microcephaly, soliosis, and mental retardation. We propose that he has a new syndrome. © 1995 Wiley-Liss, Inc. 相似文献
89.
A patient homozygous for the SCA6 gene with retinitis pigmentosa 总被引:1,自引:0,他引:1
The present authors studied a 55-year-old-patient homozygous for the SCA6 gene who experienced frequent attacks of positional vertigo at 37 years of age with subsequent staggering gait and night blindness. Retinitis pigmentosa (RP), as well as cerebellar ataxia and vertical antidirectional nystagmus, were detected. The subject's parents were first cousins, and two of his three male cousins, whose parents were also first cousins, had RP without ataxia or nystagmus. The numbers of CAG repeats in the expanded alleles of the SCA6 gene found by molecular analysis were 21 and 21. The genetic results were negative for SCA1, SCA2, SCA3, SCA7 and dentatorubral pallidoluysian atrophy. The retinal degeneration in this patient is most likely to be secondary to a genetic disorder of autosomal or X-linked recessive inheritance rather than SCA6. Other reported cases of patients homozygous for the SCA6 gene are also reviewed. 相似文献
90.
鄂伦春族Y染色体短串联重复序列多态性研究 总被引:4,自引:1,他引:4
目的 调查鄂伦春族Y染色体上10个短串联重复序列基因座及单倍型的遗传多态性。方法 应用PCR和变性聚丙烯酰胺凝胶电泳结合银染显色分型技术,检测102名无关系鄂伦春族男性血样。结果 在DYS392、DYS438、DYS439、DYS456、DYS459、DYS460、DYS461、DYS462、DYS389Ⅰ、DYS389Ⅱ等10个基因座中共检出44个等位基因,等位基因频率分布在0.418(DYS461)至0.727(DYS389Ⅰ)之间,除了DYS461(0.418)和DYS462(0.479)以外,其余等位基因频率均大于0.5。由10个基因座组成的Y染色体单倍型系统单倍型有101种,单倍型频率0.99。结论 上述10个Y-短串联重复基因座在鄂伦春族群体中具有较好的多态性,单倍型具有很高的遗传多态性。 相似文献