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71.
Six familial cases of the Beemer–Langer syndrome (BLS) were analyzed to further elucidate the spectrum and frequency of anomalies observed in this disorder. Preaxial polydactyly was found in 3/6 affected sibs, and, therefore, its frequency previously may have been underestimated. Some patients, described as infants affected with the Majewski syndrome (MS) or “atypical” short rib-poly-dactyly conditions, may indeed have BLS. A high frequency of brain defects (16/26) and cleft tongue, oral frenula, and/or natal teeth (13/29) widens the list of typical findings in this syndrome. The specific type of tibial defect seems to be the most important discrimination of the MS and the BLS. © 1994 Wiley-Liss, Inc.  相似文献   
72.
BACKGROUND: Environmental control has been put forward as an integral part of the management of house dust mite (HDM) allergy in sensitized patients. To validate this statement allergic disorders involved in HDM allergy--allergic asthma, rhinitis and atopic eczema/dermatitis syndrome (AEDS)--should be taken together and studied in terms of the efficacy of environmental control. Because a generic quality of life questionnaire exceeds the border of disease, this may be used as major outcome parameter. RESEARCH OBJECTIVE: To study the effects of bedding encasings in HDM allergic patients with asthma, rhinitis and AEDS. MATERIAL AND METHODS: A total of 224 adult HDM allergic patients with rhinitis and/or asthma and/or dermatitis were randomly allocated impermeable or nonimpermeable encasings for mattress, pillow and duvet. Short form 36 (SF-36) was filled in at baseline and after 12 months. Results: Lower physical (P = 0.01) and emotional (P < 0.001) sumscores were seen in females. Also, the presence of asthma resulted in lower physical sumscore (P = 0.01). However, no effect was seen of encasings on either sumscore. CONCLUSION: Bedding encasings do not improve quality of life in a mixed population of subjects with combinations with rhinitis, asthma and atopic dermatitis and sensitized to HDMs.  相似文献   
73.
目的 了解广西融水县苗族群体中15个短串联重复序列(STR):TPOX、TH01、CSFIPO、D19S433、vWA、D18S51、D5S818、FGA、D8S1179、D21S11、D7S820、D3S1358、D13s317、D16S539、D2S1338遗传多态的分布情况.方法 用枸橼酸钠抗凝法采集融水县苗族的血样,酚.氯仿抽提法提取DNA,用AmpFISTRR Identifiler TM PCR Amplification kit荧光标记复合扩增技术和ABI 3100型遗传分析仪对DNA进行扩增检测.结果 15个STR分别检测出5~20种等位基因,11~62种基因型,基因型的分布符合Hardy-Weinberg平衡定律,等位基因频率和基因型频率分布在0.002 4~0.4663和0.004 8~0.274 0之间;平均杂合度0.781 1,累积个人识别力1.000 000 000 00,累积非父排除率0.999 999 998,多态信息总量0.999 999 999 4.结论 广西融水苗族群体的15个短串联重复序列基因座具有高度多态性和遗传稳定性,实用价值高,可作为广西苗族群体的民族遗传学研究和法医学鉴定的基础数据.  相似文献   
74.
Grebe chondrodysplasia and brachydactyly in a family   总被引:1,自引:0,他引:1  
A family is reported in which various skeletal abnormalities have been segregating over three generations. The Great-grandfather (11) of the consultand had features consistent with Grebe chondrodysplasia. The other members of the family have brachydactyly, radiologically characterised by short first metacarpals and short middle phalanges of the index and little fingers. The possibility of association of familial brachydactyly and Grebe chondrodysplasia is discussed. An attempt has been made to deal with the genetic counselling problem in this particular family.  相似文献   
75.
目的提高经典型苯丙酮尿症的产前诊断的成功率。方法在苯丙氨酸羟化酶(phenylalanine hydroxylase,PAH)基因附近选择了3个新的短串联重复序列(short tandem repeat,STR)位点(PAH26、PAH32和PAH9),进行扩增长度片段多态性分析,确定它们在中国人群的分布及在诊断中的应用价值。结果3个新的STR位点的多态信息含量分别为0.518(PAH26)、0.413(PAH32)和0.362(PAH9)。这3个位点之间,PAH9与第3内含子中的STR位点(TCTA)n之间存在连锁不平衡,其他位点组合不存在连锁不平衡。联合第3内含子中的STR位点(TCTA)n和2个新的位点,可以对家系中突变基因标记进行95%N断,并成功地用于4例产前诊断中。结论选择性地应用PAH基因中的3个STR位点组合,可以95%地区分经典型苯丙酮尿症家系中父母的两个基因,从而准确地进行快速产前诊断。  相似文献   
76.
Summary Southern hybridization of the total DNA of Agrocybe aegerita with cloned mitochondrial (mt) probes revealed a sequence homology between two distant mitochondrial restriction fragments. From the mtDNA restriction map and the distribution of restriction sites on the cross-hybridizing mitochondrial fragments, two copies of a large inverted repeated sequence (IR) of 3 kbp were located on the mitochondrial genome. These IR sequences divided the 80 kbp mtDNA into two singlecopy regions of 24 kbp (SSC) and 50 kbp (LSC). For the first time in higher fungi, this IR sequence has been shown to be involved in an intramolecular homologous recombinational event. Such a rearrangement led to an inversion of the orientation of the two unique-copy regions, without any change in mtDNA complexity. The location of the recombinational event was compared with previously reported plant and fungal mitochondrial rearrangements and the potential role of the IR sequence was discussed.  相似文献   
77.
Partial duplication of 10q is a recognizable clinical entity. In most of the reported cases, the trisomic segment is identified by a balanced translocation state in a parent. Verification remains a problem in de novo cases. However, the recent availability of whole chromosome probes allows for confirmatory diagnosis of suspected cases. We describe a case of de novo duplication (10q) wiht verification using DNA in situ hybridization. © 1994 Wiley-Liss, Inc.  相似文献   
78.
We have studied 4 patients with inverted tandem duplications of parts of chromosomes, a hitherto rarely identified from of a structural rearrangement involving a single chromosome in man. In Patients 1 and 2, the duplication involved parts of the short arm of chromosome 8 (regions 8p 12→8p23 and 8p21→8p23, respectively). Both patients manifested certain characteristics of the mosaic trisomy 8 syndrome. Elevated levels of glutathione reductase (GSR) in their erythrocytes supported the interpretation of a partial duplication of chromosome 8 and indicated a regional localization for the GSR gene locus. In Patient 3, the distal half of the long arm of chromosome 4 was duplicated (region4q26→4q35). Clinical evidence supported this interpretation, as Patient 3 resembled phenotypically the 13 reported cases with duplication of the distal 4q. The cytogenetic findings in Patient 4 suggested a possibly inverted duplication of 22q. The clinical correlation was less convincing due to the lack of a well-defined phenotype for trisomy 22. These chromosome aberrations had occurred de novo in all 4 cases. Although they involved different chromosomal regions, they might well have arisen by the same mechanism. Possible modes of origin that are discussed in detail include unequal exchange between homologous chromosomes, between chromatids of 1 chromosome or between strands of 1 DNA duplex.  相似文献   
79.
目的获得20个Y染色体短串联重复序列(Yshort tandemrepeats,Y-STR)基因座及其单倍型在潮汕地区汉族人群中的遗传多态性分布情况,评估其法医学应用价值。方法通过建立3组Y-STR荧光标记复合扩增系统(MultiplexⅠ:DYS434,Y-GATA-A10,DYS438,DYS439,DYS531,DYS557,DYS448,DYS456,DYS444;MultiplexⅡ:DYS458,DYS460,DYS443,DYS447,DYS446,DYS709;MultiplexⅢ:DYS622,DYS635,Y-GATA-H4,DYS520,DYS630),对潮汕地区汉族158名无关男性个体进行20个STR基因座的复合扩增,用ABI310基因分析仪对扩增产物进行检测,统计20个Y-STR基因座的群体遗传学参数。结果3组复合扩增系统均可成功进行分型,基因多样性(gene diversity,GD)值最低为0.2506(DYS434),最高为0.8034(DYS447);20个Y-STR基因座共同构成的单倍型157种,其中156种为唯一的,单倍型多样性为0.999998。另对30个父性家系调查显示:同一家系成员20个Y-STR基因座单倍型一致,未观察到基因突变。结论20个Y-STR基因座具有丰富的遗传多态性,父系遗传稳定,建立的3组Y-STR荧光标记复合扩增系统分型可靠,可用于法医学个体识别和亲权鉴定。  相似文献   
80.
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