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71.
The effects of chronic estrogen withdrawal and subsequent hormone replacement on the feeding and body weight of adult lean and genetically obese Zucker rats were investigated. Following confirmation of a delay in the vaginal canalization of the fatty rat, subgroups of each genotype received either ovariectomy or sham surgery (Experiment 1). One hundred days later all subjects were injected subcutaneously (SC) with 1.0 microgram of estradiol benzoate (EB) daily for 16 treatment days (Experiment 2A). A second series of daily 2.0 microgram EB injections was administered intraperitoneally (IP) for 1 week (Experiment 2B). The first experiment revealed that ovariectomy produced overeating and similar weight gains in both genotypes. In the second experiment, SC hormone treatment completely reversed ovarian obesity in lean animals but failed to alter the food intake or weight gain of fatty rats. IP administration of EB depressed the feeding of fatty and lean animals to a comparable degree but a reduction in weight gain was observed only in the lean rats. These findings are discussed in light of current theories of estrogenic modulation of energy balance. 相似文献
72.
采用时域有限差分(FDTD)法结合遗传算法(GA)优化设计了适用于浅表生物组织高频测量的宽带同轴贴片探头,并用该探头测量了人体背部1~7GHz频带内的反射特性。优化设计出的圆形同轴贴片探头具有轴对称特点,辐射近场在生物组织中透人深、反射系数的频率响应特性好。所获得的人体背部反射特性的测量结果将为背部浅表组织电特性的重建提供有利的依据。 相似文献
73.
维生素D受体基因多态性与乙型肝炎病毒感染的关联研究 总被引:5,自引:0,他引:5
目的探讨中国汉族人群维生素D受体(vitamin D receptor,VDR)基因多态性是否与乙型肝炎病毒(hepatitis B virus,HBV)感染结局相关联。方法以184例慢性乙肝患者和205名无症状HBV携带者为研究对象,收集外周血,提取基因组DNA,应用聚合酶链反应.限制性片段长度多态性(polymerase chain reaction-restriction fragmentlength polymorphism,PCIR-RFLP)方法,分析VDR基因第2外显子Fok Ⅰ位点、第9外显子Taq Ⅰ位点的多态性分布。结果单因素分析结果显示Fok Ⅰ位点FF基因型在慢性乙肝组的频率44.6%显著高于无症状HBV携带组的31.7%(P〈0.05)。经多因素非条件Logistic回归分析调整混杂作用后,结果仍然显示FF基因型在慢性乙肝组与无症状HBV携带组之间的差异存在统计学意义(OR=1.95,P〈0.05)。FokⅠ位点与TapⅠ位点组成的FT单倍型在慢性乙肝组的分布频率显著高于无症状HBV携带组(OR=1.45,P〈0.05),fT单倍型在慢性乙肝组的分布频率显著低于无症状HBV携带组(OR=0.72,P〈0.05)。结论维生素D受体基因多态性可能影响HBV感染的遗传易感性。 相似文献
74.
目的探讨染色体核型异常与生育异常的关系。方法对2004年5月至2007年4月到吉林大学特殊疾病检测站进行遗传咨询的816例患者进行外周血淋巴细胞培养,进行染色体核型分析。结果受检的生育异常患者为816例,核型异常99例,异常率为12.13%。其中常染色体异常22例,占22.22%,性染色体异常46例,占46.46%,嵌合体异常31例占31.31%。结论染色体异常是生殖异常的重要原因之一,对生育异常患者进行染色体检查可为临床诊断和优生优育提供依据。 相似文献
75.
Rosenzweig SD Schäffer AA Ding L Sullivan R Enyedi B Yim JJ Cook JL Musser JM Holland SM 《Clinical immunology (Orlando, Fla.)》2004,112(1):113-119
Different polymorphisms have been described in the minimal promoter region (MPR) of the interferon-gamma receptor 1 (IFNGR1), a molecule that plays a critical role in mycobacterial control. We sequenced the IFNGR1 MPR from African American, Caucasian and Korean controls, and from mycobacteria-infected patients. Six different single nucleotide polymorphisms (SNPs) were detected in the IFNGR1 MPR. The three ethnic groups showed different SNP distribution patterns, but no significant differences were detected between mycobacterial cases and controls. Two polymorphisms were found in all populations (G-611A, T-56C). We cloned the four allelic variants (var) of haplotype G-611A/T-56C into a luciferase reporter vector and determined their promoter activity. Polymorphisms at position -611 had a stronger effect on the promoter activity than those at position -56, and constructs carrying G-611 produced a stronger promoter activity than -611A constructs. The IFNGR1 MPR is a polymorphic region with at least two SNPs influencing its activity, but these are not associated with increased mycobacterial susceptibility. 相似文献
76.
Yuasa I Nakamura H Henke L Henke J Nakagawa M Irizawa Y Umetsu K 《Journal of human genetics》2001,46(10):572-578
In this study, the structure of the α1-acid glycoprotein (AGP), or orosomucoid (ORM), gene was investigated in a Ghanaian mother and her child, who shared an unusual variant, ORM1 S2(C), found by isoelectric focusing. Three remarkable changes of nucleotide sequence were observed: (1) The two ORM1 alleles,
ORM1
*
S and ORM1
*
S2(C), had the AGP2 gene-specific sequence at one and three regions, respectively, in exon 5 to intron 5. The variant allele originating from
ORM1
*
S was characterized by a G-to-A transition, resulting in an amino acid change from valine to methionine, which is also detected
in ORM1 F2, a form that is common in Europeans. (2) The AGP2 gene of the child, inherited from the father, was duplicated, as revealed by long-range polymerase chain reaction. (3) Three
new mutations were observed in two exons of the AGP2 genes of the mother and child. All of these novel genomic rearrangements, which were not observed in Japanese subjects, may
have arisen through point mutation, gene conversion, and unequal crossover events. It is likely that the rearrangement of
the AGP gene has often occurred in Africans.
Received: June 15, 2001 / Accepted: July 10, 2001 相似文献
77.
Kerr PJ Perkins HD Inglis B Stagg R McLaughlin E Collins SV Van Leeuwen BH 《Virology》2004,324(1):117-128
Rabbit IL-4 was expressed in the virulent standard laboratory strain (SLS) and the attenuated Uriarra (Ur) strain of myxoma virus with the aim of creating a Th2 cytokine environment and inhibiting the development of an antiviral cell-mediated response to myxomatosis in infected rabbits. This allowed testing of a model for genetic resistance to myxomatosis in wild rabbits that have undergone 50 years of natural selection for resistance to myxomatosis. Expression of IL-4 significantly enhanced virulence of both virulent and attenuated virus strains in susceptible (laboratory) and resistant (wild) rabbits. SLS-IL-4 completely overcame genetic resistance in wild rabbits. The pathogenesis of SLS-IL-4 was compared in susceptible and resistant rabbits. The results support a model for resistance to myxomatosis of an enhanced innate immune response controlling virus replication and allowing an effective antiviral cell-mediated immune response to develop in resistant rabbits. Expression of IL-4 did not overcome immunity to myxomatosis induced by immunization. 相似文献
78.
Lazar A Gründemann D Berkels R Taubert D Zimmermann T Schömig E 《Journal of human genetics》2003,48(5):226-230
The extraneuronal monoamine transporter EMT (HGNC Nomenclature SLC22A3) is the molecular correlate of the classical uptake2 system responsible for the non-neuronal inactivation of circulating and centrally released catecholamines. Because of its
functional profile and expression pattern, EMT is regarded as a candidate gene for diseases related to the sympathetic nervous
system and neuropsychiatric disorders. We describe the first investigation of the genetic variability of the EMT gene in human.
Six single-nucleotide substitutions and one deletion were detected within the assumed core promoter, the exonic and flanking
intronic sequences and the 3'-untranslated region in 100 Caucasian individuals. No amino acid changes were found and Tajima's
D was positive (D=2.91; P<0.01). However, the synonymous nucleotide substitution 1233G→A might serve as a cryptic splice acceptor site. Analysis of
linkage disequilibrium between polymorphisms yielded 12 possible haplotypes accounting for more than 90% of all haplotypes.
Knowledge of the sequence variation and frequency of the underlying polymorphisms in this member of the amphiphilic solute
facilitator family of transporters provides the basis for subsequent association studies and candidate gene approaches.
Electronic Publication 相似文献
79.
Folwaczny M Glas J Török HP Fricke K Folwaczny C 《Clinical immunology (Orlando, Fla.)》2003,109(3):325-329
A 32-base-pair deletion in the CCR5 gene was previously shown to influence the susceptibility for several infectious diseases. The present study compared the frequency of the CCR5-Delta32 mutation among subjects with periodontal disease and healthy control individuals. The prevalence of the CCR5-Delta32 mutation was determined in 81 patients with generalized periodontitis and 121 healthy controls. Standardized clinical and radiographic criteria were used for the diagnosis of periodontitis for each subject. The CCR5-Delta32 mutation was identified by PCR amplification and subsequent agarose gel electrophoresis. Genotype and allele frequencies among both study groups were compared using Fisher's exact test at a level of significance of 5% (P<0.05). The frequency of the CCR5-Delta32 allele was 9.9% (16/162) for periodontitis patients and 10.7% (26/216) for the healthy controls. The allele frequencies between periodontitis patients and the control group for the CCR5-Delta32 mutation were not significantly different (P=0.801). The present study revealed no association between the CCR5-Delta32 mutation and susceptibility to periodontal disease. 相似文献
80.
Previous research has shown that damage to the dorsal and median raphe nuclei of rats can impede the subsequent development of hypothalamic hyperphagia and obesity as well as impair the defense of established hypothalamic obesity in response to food deprivation. The present study sought to determine if raphe injury might alter the development of another form of obesity, namely that which occurs spontaneously in the Zucker fatty rat. Subjects were 20 obese females (fafa; mean weight of 200 g) and 20 lean littermate controls (FaFa females; mean weight of 150 g). Following 10 days of baseline intake and weight recordings, half of each group received radio-frequency heat lesions of the dorsal and median raphe nuclei while the other half received sham surgery. Except for a mild suppression of food intake and weight gain during the first few days after lesioning, raphe injury did not alter the hyperphagia or obesity shown by fatties over the 7 week ad lib feeding period studied. Additional 24-hr intake tests of varying sucrose and quinine solutions revealed reduced sucrose acceptance and enhanced quinine rejection by fatties much as has been seen in previous studies of hypothalamic obese rats. Terminal assays of forebrain monoamine levels confirmed that raphe lesions were effective in depleting serotonin (-71% compared to controls) without producing major changes in norepinephrine or dopamine (-14% and +2%, respectively). The inability of raphe lesions to mitigate this form of hyperphagia and obesity suggests that earlier observations of their attenuating effects on hypothalamic obesity were not due to non-specific impairments of behavioral or metabolic factors necessary to permit overeating and weight gain. 相似文献