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71.
72.
Controlled study of Escherichia coli diarrheal infections in Bangladeshi children. 总被引:1,自引:2,他引:1 下载免费PDF全文
M J Albert S M Faruque A S Faruque P K Neogi M Ansaruzzaman N A Bhuiyan K Alam M S Akbar 《Journal of clinical microbiology》1995,33(4):973-977
Diarrheal diseases are highly prevalent in Bangladesh. However, the relative contribution of diarrheagenic Escherichia coli organisms--those that are enterotoxigenic (ETEC), enteropathogenic (EPEC), enteroinvasive, enterohemorrhagic, enteroaggregative, and diffuse adherent--to diarrhea in Bangladeshi populations is not known. With DNA probes specific for these diarrheagenic E. coli strains, we analyzed fecal E. coli from 451 children up to 5 years of age with acute diarrhea seeking treatment at a Dhaka hospital and from 602 matched control children without diarrhea from July 1991 to May 1992. Enteroinvasive E. coli was not isolated from any children; enterohemorrhagic E. coli was not isolated from any diarrheal children but was isolated from five control children; enteroaggregative and diffuse adherent E. coli strains were isolated with similar frequencies from children with and without diarrhea, thereby showing no association with diarrhea; ETEC was significantly associated with diarrhea in the diarrheal children as a whole and especially in the age groups of 0 to 24 months and 37 to 48 months (further analysis suggests an association with diarrhea for the heat-stable toxin only and for both heat-labile- and heat-stable-toxin-producing ETEC only); and EPEC was significantly associated with diarrhea in the diarrhea group as a whole and particularly in infants up to 1 year of age. Further analysis suggested that EPEC strains of only the traditional serogroups were significantly associated with diarrhea. ETEC and EPEC infections peaked during warm months. Our data thus suggest that EPEC and ETEC are important causes of acute diarrhea in children in this setting. 相似文献
73.
Soleimanifar N Amirzargar AA Mahmoudi M Pourfathollah AA Azizi E Jamshidi AR Rezaei N Tahoori MT Bidad K Nikbin B Nicknam MH 《Inflammation》2011,34(6):707-712
Ankylosing spondylitis (AS) is a chronic inflammatory disease, characterized by axial arthritis in which the genetic-environmental factors seem to be involved in the pathogenesis of the disease. This study was performed to investigate the role of polymorphisms of the programmed cell death 1 (PDCD1) gene on susceptibility to AS. In this study, 161 Iranian patients with AS and 208 normal controls were enrolled; two single-nucleotide polymorphisms (SNPs) of the PDCD1 gene PD-1.3 (G, A) in nucleotide position +7146 of intron 4 and PD-1.9 (C, T) in nucleotide +7625 of exon 5 were studied. Analysis of PD-1.3 revealed that 82% of patients and 79% of controls had GG genotype, while GA and AA genotypes were detected in 17% and 0.6% of patients, respectively, and 20% and 1.4% of controls, respectively. Moreover, the genotype CC (PD-1.9) was present in 92% of patients and 97% of controls. Although these differences were not statistically significant between patients and controls, comparisons of genotypes frequencies in the AS patients, based on human leukocyte antigen (HLA)-B27, revealed that all patients who had CT genotype (PD-1.9) were HLA-B27 positive, whereas 30% of patients with CC genotype were HLA-B27 negative. There was no evidence of association for PDCD1 SNPs with AS in our study, but CT genotype (PD-1.9) seems to be associated with HLA-B27 positivity in the patients with AS. 相似文献
74.
目的探讨异常黑胆质成熟剂(ASMq)对D-半乳糖致衰老模型大鼠P16蛋白、β-半乳糖苷酶表达的影响,以此阐明异常黑胆质成熟剂延缓衰老作用的部分机制。方法选取3个月龄雄性 SD 大鼠60只,体质量180~220 g,采用 D-半乳糖制作亚急性衰老模型,随机分为衰老模型组及 ASMq高、中、低剂量组各15只(ASMq高、中、低剂量分别为6.0、3.0、1.5 g·kg-1·d-1),连续给药21 d。另取15只正常雄性大鼠作为正常对照组。采用免疫组织化学方法检测各组大鼠心、脑、肝组织中 P16蛋白、β-半乳糖苷酶的表达。结果各组大鼠心、脑、肝脏组织中 p16蛋白、β-半乳糖苷酶表达阳性的细胞表现为细胞浆染成黄褐色。与正常对照组比较,衰老模型组心、脑、肝组织中的P16蛋白、β-半乳糖苷酶的表达明显升高,差异有统计学意义(P <0.05~0.01);与衰老模型组比较, ASMq高、中、低剂量组心、脑、肝组织中 P16蛋白、β-半乳糖苷酶的表达明显下降,差异有统计学意义(P <0.05~0.01)。结论 ASMq可降低衰老大鼠P16蛋白、β-半乳糖苷酶的表达,从而发挥抗衰老作用。 相似文献
75.
76.
Diamond-Blackfan syndrome: evidence against cell-mediated erythropoietic suppression 总被引:2,自引:1,他引:2
The profound anemia of Diamond-Blackfan syndrome (DBS) is due to marrow red cell failure, but the pathogenesis is not understood. Studies by others indicated cell-mediated erythropoietic suppression in this condition. To explore this mechanism further, Ficoll-Hypaque--separated peripheral blood lymphocytes (PBL) from four anemic untreated patients with DBS, or from normals were cocultured with control marrow in vitro and the growth of erythropoietin-responsive stem cell colonies (CFU-E) was dermined. CFU-E numbers obtained from cultures with added normal PBL were not significantly different from the number without PBL. Similarly, CFU-E from cultures with added DBS PBL were not significantly different from the number without PBL (215 versus 220, 229 versus 220 and 84 versus 60, 74 versus 94/10(5) cells, respectively). Mixing marrows from a control and one DBS patient in ratios of 2:1, 1:1, or 1:2 prior to culture failed to disclose a decrease of colony growth. We could not show cellular inhibition of erythropoiesis in these patients with DBS. The mechanism of anemia in this disorder remains an open question. 相似文献
77.
Elham Barkhordari Nima Rezaei Bita Ansaripour Pegah Larki Maryam Alighardashi Hamid Reza Ahmadi-Ashtiani Mahdi Mahmoudi Mohammad-Reza Keramati Peiman Habibollahi Mohammad Bashashati Naser Ebrahimi-Daryani Ali Akbar Amirzargar 《Journal of clinical immunology》2010,30(1):74-79
Introduction
Irritable bowel syndrome (IBS) is a multifactorial functional gastrointestinal disorder, characterized by recurrent abdominal pain and altered bowel habits. Proinflammatory cytokines can play an important role in intestinal inflammation, while their production is under genetic control.Methods
This study was performed in a group of patients with IBS to analyze the genotype frequencies of a number polymorphic genes coding for proinflammatory cytokine (interleukin-6 (IL), tumor necrosis factor-alpha (TNF-α), and IL-1 group). Using polymerase chain reaction with sequence-specific primers method, the cytokine genes were amplified, and alleles and genotypes of 71 patients with IBS were detected on gel electrophoresis, and the results were compared with healthy control subjects.Results
Results of the analyzed data showed that the frequencies IL-1R C allele at position Pst-I 1970 (P?=?0.017), IL-6 G allele at position ?174 (P?=?0.002), and TNF-α G allele at position ?238 (P?<?0.001) in the patient group were significantly higher than the control group. IL-6 GG genotype (?174) and TNF-α GG genotype (?238) in the patient group were also significantly overrepresented (P?<?0.001), while IL-6 CG genotype (?174) and TNF-α GA genotype (?238) were significantly decreased in the patients with IBS (P?<?0.001). The frequencies of IL-6 (?174, nt565) GG haplotype and TNF-α (?308, ?238) GG haplotype were also significantly higher in the patient group (P?<?0.001), whereas the frequencies of the haplotypes IL-6 CG and TNF-α GA were significantly decreased in the patients with IBS (P?<?0.001).Conclusion
IL-6 and TNF-alpha proinflammatory cytokine gene polymorphisms could change individual susceptibility to IBS and might have a role in pathophysiology of disease. 相似文献78.
Mamun Al‐Mahtab Salimur Rahman Sheikh Mohammad Fazle Akbar Mohammad Kamal Mohammad Sakirul Islam Khan 《Journal of medical virology》2010,82(8):1350-1354
Patients with inactive chronic hepatitis B virus (HBV) infection are assumed to be free from liver disease. Accordingly, antiviral drug treatment is not recommended for these patients. However, the extent of liver damage in these patients has not been evaluated fully. The aim of this study was to evaluate the extent of liver damage in patients with inactive HBV. Liver biopsy was conducted in 141 inactive HBV carriers [HBeAg‐negative, low levels of HBV DNA (≤10,000 copies/ml) and normal levels of serum alanine aminotransferase (ALT)]. The extent of hepatic inflammation and fibrosis was evaluated in these patients by examining liver biopsy specimens. Although the patients were inactive HBV carriers, mild to moderate levels of necroinflammation (HAI necroinflammation score HAI‐N1 ≥ 7) were detected in 36 of 141 (26%) patients. Seventeen patients had a severe degree of hepatic fibrosis (HAI fibrosis score HAI‐F ≥ 3). A total of 10 patients had both considerable necroinflammation (HAI‐N1≥7) and severe fibrosis (HAI‐F ≥3). All 10 patients with significant hepatic inflammation and fibrosis were male and older than 25 years. However, all were HBeAg‐negative and expressed low levels of HBV DNA and normal ALT levels. The study demonstrates that features of liver damage were present in a considerable number of the patients. Assessment of liver biopsy specimens in a larger cohort of inactive HBV carriers is necessary to establish management guidelines for such patients. J. Med. Virol. 82:1350–1354, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
79.
Elham Barkhordari Nima Rezaei Mahdi Mahmoudi Pegah Larki Hamid Reza Ahmadi-Ashtiani Bita Ansaripour Maryam Alighardashi Mohammad Bashashati Ali Akbar Amirzargar Naser Ebrahimi-Daryani 《Inflammation》2010,33(5):281-286
Inflammation and mucosal immune system activation have an important role in irritable bowel syndrome (IBS), whereas genetic
factors can control some immunological mediators. In this study, a number of polymorphic genes coding for T-helper 1, T-helper
2, and T-regulatory cytokines were genotyped in 71 patients with IBS, and the results were compared with controls. IL-4 CC
genotype at position −590, IL-4 TT genotype at position −33, and IL-10 GA genotype at position −1082 were significantly overrepresented
in the patients with IBS in comparison with controls (P < 0.001). The frequencies of the following haplotypes in the patient group were significantly higher than in the control
group: IL-2 (−330, +160) GT haplotype (P = 0.002), IL-4 (−1098, −590, −33) TCC haplotype (P < 0.001), and TCT haplotype (P < 0.001). While production of cytokines could be affected by genetic polymorphisms within coding and promoter regions of
cytokine genes, IL-4 and IL-10 gene polymorphisms could affect individual susceptibility to IBS. 相似文献
80.
It has been suggested that histamine have modulatory influence on anxiety-related behaviours both in animals and humans. Ventral hippocampus (VHC) may also be an important brain site in the modulation of fear or anxiety. In the present study, the effects of histaminergic agents on anxiety-related behaviours in the rats, using plus-maze test has been investigated. Intra-VHC administration of histamine (2.5, 5 and 7.5 microg/rat) decreased %OAT and %OAE but not locomotor activity, showing an anxiogenic response. Pretreatment of animals with either pyrilamine, a H1 receptor antagonist (10 microg/rat), or ranitidine, a H2 receptor antagonist (10 microg/rat) reverse anxiogenic response of histamine (2.5, 5 and 7.5 microg/rat). However, intra-VHC microinjection of higher doses of pyrilamine (40 microg/rat) or ranitidine (20 and 40 microg/rat) alone increased anxiety-like behaviours in rats. Our results showed that histamine may modulate anxiety-like behaviours via H1 and H2 receptors in the ventral hippocampus of the rats. 相似文献