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31.
Mid-aortic syndrome (MAS) is a rare vascular disorder that causes refractory hypertension. A 76-year-old woman was hospitalized for acute heart failure (HF) with drug-resistant hypertension; other comorbidities included epigastric artery rupture, old myocardial infarction, an intraventricular thrombus, and a cerebral artery aneurysm. Angiography revealed severe narrowing of the descending aorta, which led to the diagnosis of MAS. Although intensive medical treatment improved her HF, optimal blood pressure (BP) could not be achieved. Percutaneous coronary intervention and surgical bypass for diseased aorta was then performed in two stages, resulting in the achievement of optimal BP and alleviation of HF.  相似文献   
32.
青盲症西医称青光眼。该病是由眼内房水增多 ,致使眼压升高的一种临床常见病。蒙医学认为该病的生成是由于“三根、七素”失常 ,致房水增多 ,头疼眼胀 ,视物日渐昏朦 ,继而瞳孔变青色 ,终至失明的一种眼病 ,蒙医称青盲症。对该病的治疗蒙医常分为三种型 ,即 :血、希拉型青盲症 ,赫依、血型青盲症 ,巴达干、赫依型青盲症。1 临床表现青盲症患者长期因血希拉热及肝火上攻于目 ,或因巴达干、赫依性病气血渐衰 ,正精日损 ,目失涵养所致 ,或由昏朦症转变而成。一般病初无自觉症状 ,有轻度眼珠胀痛和前额及头部疼痛 ,视物时明时朦 ,视力逐渐下降 …  相似文献   
33.
Single nucleotide polymorphisms (SNPs) have been widely used in forensics for prediction of identity, biogeographical ancestry (BGA) and externally visible characteristics (EVCs). Single base extension (SBE) assays, most notably SNaPshot® (Thermo Fisher Scientific), are commonly used for forensic SNP genotyping as they can be employed on standard instrumentation in forensic laboratories (e.g. capillary electrophoresis). High resolution melt (HRM) analysis is an alternative method and is a simple, fast, single tube assay for low throughput SNP typing. This study compares HRM and SNaPshot®. HRM produced reproducible and concordant genotypes at 500 pg, however, difficulties were encountered when genotyping SNPs with high GC content in flanking regions and differentiating variants of symmetrical SNPs. SNaPshot® was reproducible at 100 pg and is less dependent on SNP choice. HRM has a shorter processing time in comparison to SNaPshot®, avoids post PCR contamination risk and has potential as a screening tool for many forensic applications.  相似文献   
34.
目的 评价平台转换种植体在上颌前牙区的应用效果,探讨平台转换技术对种植体周围组织的影响.方法 上颌前牙区单牙种植患者55例共60枚,分为2组,平台转换组25例,共28枚Ankylos系统种植体;平齐对接组30例,共32枚Nobel Replace系统种植体.分别于完成修复后1年和2年,观察种植体周围骨组织情况,计算红色美学得分(pink esthetic score,PES),比较2组种植体边缘骨组织和周围软组织的变化.结果种植体修复1年后,平台转换组种植体边缘骨变化量为(-0.41±0.36)mm,PES为10.43±1.37,平齐对接组种植体边缘骨平均变化量为(-1.77±0.54)mm,PES平均值为9.21±0.97;2年后,平台转换组骨变化量为(-0.55±0.33)mm,PES为10.32±1.21,平齐对接组边缘骨平均变化量为(-1.82±0.61)mm,PES为9.16±0.95.修复后1、2年,2组的种植体周围边缘骨吸收量和PES差异均具有统计学意义.结论 平台转换种植体在上颌美学区单牙种植修复能更有效保留周围骨组织及具有更佳的美学效果.  相似文献   
35.
Ali FR  Kay AB  Larché M 《Thorax》2007,62(9):750-757
BACKGROUND: Subjects with allergic asthma develop isolated late asthmatic reactions after inhalation of allergen-derived T cell peptides. Animal experiments have shown that airway hyperresponsiveness (AHR) is CD4+ cell-dependent. It is hypothesised that peptide inhalation produces increases in non-specific AHR and a T cell-dominant bronchial mucosal inflammatory response. METHODS: Bronchoscopy, with bronchial biopsies and bronchoalveolar lavage (BAL), was performed in 24 subjects with cat allergy 6 h after aerosol inhalation of short overlapping peptides derived from Fel d 1, the major cat allergen. Biopsy specimens and BAL fluid were studied using immunohistochemistry and ELISA. RESULTS: Twelve of the 24 subjects developed an isolated late asthmatic reaction without a preceding early (mast cell/histamine-dependent) reaction characteristic of whole allergen inhalation. These responders had significant between-group differences (responders vs non-responders) in the changes (peptide vs diluent) in AHR (p = 0.007) and bronchial mucosal CD3+ (p = 0.005), CD4+ (p = 0.006) and thymus- and activation-regulated chemokine (TARC)+ (p = 0.003) but not CD8+ or CD25+ cells or eosinophils, basophils, mast cells and macrophages. The between-group difference for neutrophils was p = 0.05 but with a non-significant within-group value (peptide vs diluent, responders, p = 0.11). In BAL fluid there was a significant between-group difference in TARC (p = 0.02) but not in histamine, tryptase, basogranulin, C3a or C5a, leukotrienes C(4)/D(4)/E(4), prostaglandins D(2) or F(2alpha). CONCLUSIONS: Direct activation of allergen-specific airway T cells by peptide inhalation in patients with atopic asthma leads to increased AHR with local increases in CD3+ and CD4+ cells and TARC but no significant changes in eosinophils or basophil/mast cell products. These findings support previous animal experiments which showed a CD4+ dependence for AHR.  相似文献   
36.
Kumar V  Naik RS  Hillert M  Klein J 《Brain research》2006,1122(1):222-229
Brain edema is a serious consequence of hemispheric stroke and traumatic brain injury and contributes significantly to patient mortality. In the present study, we measured water contents in hippocampal slices as an in vitro model of edema formation. Excitotoxic conditions induced by N-methyl-D-aspartate (NMDA, 300 microM), as well as ischemia induced by oxygen-glucose deprivation (OGD), caused cellular edema formation as indicated by an increase of slice water contents. In the presence of furosemide, an inhibitor of the Na,K,Cl-cotransporter, NMDA-induced edema were reduced by 64% while OGD-induced edema were unaffected. The same observation, i.e., reduction of excitotoxic edema formation but no effect on ischemia-induced edema, was made with chloride transport inhibitors such as DIDS and niflumic acid. Under ischemic conditions, modulation of GABAA receptors by bicuculline, a GABA antagonist, or by diazepam, a GABAergic agonist, did not significantly affect edema formation. Further experiments demonstrated that low chloride conditions prevented NMDA-induced, but not OGD-induced, water influx. Omission of calcium ions had no effect. Our results show that NMDA-induced edema formation is highly dependent on chloride influx as it was prevented by low-chloride conditions and by various compounds that interfere with chloride influx. In contrast, OGD-induced edema observed in brain slices was not affected by modulators of chloride fluxes. The results are discussed with reference to ionic changes occurring during tissue ischemia.  相似文献   
37.
The type 1 diabetes mellitus (T1DM) candidate gene SNP IL6-174G/C was genotyped in 253 Danish T1DM families (1129 individuals). TDT analysis demonstrated linkage in the presence of association between the IL6-174C allele and T1DM in the 416 T1DM offspring, P(tdt)=0.04. Gender conditioned TDT analyses revealed that linkage and association with T1DM were present in females exclusively; P(tdt)=6.5 x 10(-4) and P(tdt)=2.4 x 10(-4), respectively. Random transmission of the IL6-174C/G alleles was found in T1DM males, non-T1DM males and non-T1DM females; all P(tdt)>/=0.37. Heterogeneity analyses (T1DM versus non-T1DM females) excluded preferential meiotic segregation in females, P=4.6 x 10(-3), and demonstrated differences in the transmission patterns between female and male T1DM offspring, P=5.1 x 10(-3). The IL6-174 CC genotype was associated with younger age at onset of T1DM in females (P=0.002). The impact of 17beta-estradiol (E(2)) on the IL6-174G/C variants was investigated by reporter studies. The PMA stimulated activity of the T1DM risk IL6-174C variant exceeded that of the T1DM protective IL6-174G variant by approximately 70% in the absence of E(2) (P(c)=0.004), but not with E(2) present (P(c)=0.12). The PMA stimulated activity of the IL6-174G variant was repressed without E(2) present, but was derepressed by addition of E(2), P(c)=0.024. In contrast, the PMA stimulated IL6-174C activity was unaffected by E(2) as were the constitutive activities of the IL6-174G/C variants. In conclusion, higher IL6 promoter activity may confer risk to T1DM in very young females. This excess risk is negated with increasing age, possibly by the increasing E(2) levels in puberty.  相似文献   
38.
The synthesis of the ubiquitous tripeptide glutathione is impaired in patients with glutathione synthetase deficiency. The defect is inherited in an autosomal recessive manner, and the diagnosis is based on clinical, biochemical, and genetic criteria. In seven of our 30 index cases, however, no disease causing mutations could be identified in the coding exons or exon-intron boundaries of the glutathione synthetase gene GSS. These patients had severely decreased glutathione synthetase activities in lysates of cultured fibroblasts, and the levels of the enzyme were undetectable using a polyclonal antibody raised against human glutathione synthetase. RT-PCR mediated sequence analysis revealed previously not reported splice mutations in all patients. Thus, we conclude that in the investigation of patients with glutathione synthetase deficiency, and probably other genetic diseases as well, it might be time saving to initiate mutation analysis with sequencing of mRNA.  相似文献   
39.
40.
The antioxidant glutathione is found in low levels in diseases in which increasing evidence implicate oxidative stress in the development of the disease, for example retinopathy of prematurity, necrotizing enterocolitis, bronchopulmonary dysplasia, patent ductus arteriosus and asthma. Glutathione is metabolized in the gamma-glutamyl cycle, which involves six different enzymes. The synthesis of glutathione is a two-step process in which the first step is catalysed by gamma-glutamylcysteine synthetase and the second step by glutathione synthetase. Glutathione synthetase deficiency is an autosomal recessive disease and the most common inborn error of the gamma-glutamyl cycle. Approximately 25% of patients with hereditary glutathione synthetase deficiency die during childhood. Patients present with a clinical picture ranging from compensated haemolytic anaemia to a complex disorder with additional symptoms like 5-oxoprolinuria, metabolic acidosis and central nervous system impairment. Even though the correlation between phenotype and genotype in these patients is complex, an indication of the phenotype can be based on the type of mutation involved. Also, there is a correlation between the glutathione synthetase activity and the level of glutathione in cultured fibroblasts. Inborn errors have also been described in three additional steps of the y-glutamyl cycle, namely gamma-glutamyl-transpeptidase, 5-oxoprolinase and gamma-glutamylcysteine synthetase. Conclusion: The range of disorders in patients with inborn errors in the metabolism of glutathione illustrates the intricate metabolism of glutathione and its involvement in numerous essential processes in the cell. By studying these patients, further insight into the functions and metabolism of glutathione can be achieved.  相似文献   
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