首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   46篇
  免费   1篇
  2023年   2篇
  2021年   2篇
  2019年   1篇
  2018年   1篇
  2017年   3篇
  2014年   2篇
  2013年   5篇
  2012年   2篇
  2011年   2篇
  2010年   3篇
  2009年   5篇
  2008年   5篇
  2007年   2篇
  2006年   2篇
  2005年   2篇
  2003年   1篇
  2002年   1篇
  2001年   1篇
  2000年   2篇
  1995年   1篇
  1983年   1篇
  1978年   1篇
排序方式: 共有47条查询结果,搜索用时 125 毫秒
41.
Fibrous dysplasia (FD) is a relatively uncommon disorder that affects primarily the cranial region; its occurrence in the cranial base in combination with hindbrain herniation and aneurysmal bone cyst (ABC) constitutes an extremely rare condition. We report a case of polyostotic fibrous dysplasia with progressive occipital, temporal, and clival involvement. Clinical findings and differential diagnosis with special emphasis on the imaging features were discussed. A small posterior fossa volume has been thought to lead to hind brain herniation. The resultant obstruction to the CSF pathways at the level of the foramen magnum has been implicated in the development and subsequent progression of syringobulbia.  相似文献   
42.
doi: 10.1111/j.1741‐2358.2011.00514.x Correlation between residual ridge resorption and radiomorphometric indices Objectives: The study evaluated the relationship between residual ridge resorption (RRR) and radiomorphometric indices, including mandibular cortical index (MCI), mandibular cortical width (MCW) and panoramic mandibular index (PMI), along with demographic factors. Material and methods: Panoramic radiographs of 1863 patients over 20 years of age were assessed. Gender, age and dental status of each patient were recorded. Relationships between RRR and demographic factors and radiomorphometric indices were evaluated using chi‐square and Fisher’s exact tests with level of significance of p = 0.05. Results: Residual ridge resorption was not affected by gender (p > 0.05), but was more frequently seen in patients over the age of 50 compared with those below 49 years of age (p < 0.001). RRR was significantly associated with edentulism (p < 0.001) and with severe erosions of endosteal margin of mandible (p < 0.05). RRR was more frequently seen in patients with PMI below 0.30 (p < 0.001) and with MCW below 3 mm in 50‐ to 69‐year‐old age group (p < 0.001). Conclusions: Patients younger than 50 years of age who demonstrate severe erosions of endosteal margin of mandible and have MCW < 3 mm and PMI < 0.30 appear to be suitable candidates for early implant placement or for maintaining roots or natural teeth to preserve bone, regardless of gender.  相似文献   
43.
The etiopathogenesis of thyroid cancer has not been clearly elucidated although the role of chronical inflammation and the imbalance between pro- and anti-inflammatory cytokines may play a role in the etiology. The aim of the present study was to investigate whether cytokine gene polymorphisms are associated with papillary thyroid cancer (PTC), and to evaluate the relationship between genotypes and clinical/laboratory manifestation of PTC. Tumor necrosis factorα (TNFα) G-308A (rs 1800629), interleukin-6 (IL-6) G-174C (rs 1800795) and IL-10 A-1082G (rs 1800896) single nucleotide polymorphisms in DNA from peripheral blood leukocytes of 190 patients with thyroid cancer and 216 healthy controls were investigated by real-time PCR combined with melting curve analysis. There was no notable risk for PTC afflicted by TNFα-308 and IL-6-174 alone. However, IL-10-1082 G allele frequency were higher among PTC patients than healthy controls (p = 0.009). The patients with IL-10-1082 GG geotype have twofold increased risk of developing thyroid cancer according to AA genotype (OR 2.07, 95 % CI 1.21–3.55). In addition, the concomitant presence of IL-10-1082 G allele (GG + AG genotypes) together with IL-6 -174 GG genotype has a nearly twofold increased risk for thyroid cancer (OR 1.75 with 95 % CI 1.00–3.05, p = 0.049). We suggest that IL-10-1082 G allele is associated with an increased risk of PTC. The polymorphism of IL-10 gene can improve our knowledge about the pathogenesis of PTC, and could provide to estimate people at the increased risk for PTC.  相似文献   
44.
Follistatin (Fst) functions to bind and neutralize the activity of members of the transforming growth factor-β superfamily. Fst has a well-established role in skeletal muscle, but we detected significant Fst expression levels in interscapular brown and subcutaneous white adipose tissue, and further investigated its role in adipocyte biology. Fst expression was induced during adipogenic differentiation of mouse brown preadipocytes and mouse embryonic fibroblasts (MEFs) as well as in cold-induced brown adipose tissue from mice. In differentiated MEFs from Fst KO mice, the induction of brown adipocyte proteins including uncoupling protein 1, PR domain containing 16, and PPAR gamma coactivator-1α was attenuated, but could be rescued by treatment with recombinant FST. Furthermore, Fst enhanced thermogenic gene expression in differentiated mouse brown adipocytes and MEF cultures from both WT and Fst KO groups, suggesting that Fst produced by adipocytes may act in a paracrine manner. Our microarray gene expression profiling of WT and Fst KO MEFs during adipogenic differentiation identified several genes implicated in lipid and energy metabolism that were significantly downregulated in Fst KO MEFs. Furthermore, Fst treatment significantly increases cellular respiration in Fst-deficient cells. Our results implicate a novel role of Fst in the induction of brown adipocyte character and regulation of energy metabolism.  相似文献   
45.
Pichia stipitis strain NRRL Y-11,543 was mutagenized with N-methyl-N′-nitro-N-nitrosoguanidine (NTG) to improve xylanolytic activity. A total of 20,000 mutants were screened for xylanase overproduction by observing the clear zones around the colonies on remazol-briliant-blue-xylan (RBB-xylan)-containing agar. Of 94 mutants isolated 11 of them were found to have enhanced xylanase activity compared to the parental strain. The most active mutant NP54376 had superior properties to the wild type which included: double the enzyme activity of wild type, a shorter generation time of 2.22 h compared to 3.13 h when grown on xylan, and an enhanced growth and yield of xylanase when low levels of xylose were added to the medium. Zymogram analysis of the crude enzyme preparations from both NP54376 and the wild type by isoelectric focusing showed multiple bands ranging between pI 4.2 and 7.4. No significant difference was observed in the K m and V max values of the parental strain and NP54376. K m and V max values of xylanase for birchwood xylan were 4.2 mg ml−1 and 0.08 μmol min−1 mg−1 of protein, respectively. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
46.
47.
Blackberry mutants were induced by the irradiation of blackberry shoots with 5 kilo radians of cobalt (60Co) gamma irradiation. Seven mutant plants demonstrating improved plant growth properties were selected for evaluation of the fruit quality characteristics, such as size, shape, color, firmness, soluble solids content, juice acidity, nutritive value (e.g. ascorbic acid) and overall fruit flavor. The organoleptic properties, including texture, firmness, flavor, sweetness, acidity, color, and overall fruit flavor, were evaluated by a consumer panel. The results indicated that irradiation induced changes in some of the quality parameters of blackberry fruits, as well as increased the fruit shelf-life.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号