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21.
Aim: Findings of hypoxia prior to death and involvement of a dysregulation of the serotonergic network in sudden infant death syndrome (SIDS) may indicate that brain‐derived neutrophic factor (BDNF) also is of importance with regard to sudden unexpected infant death. Based on this, the purpose of this study was to investigate the BDNF val66met polymorphism in SIDS cases, cases of infectious death and controls. Methods: The polymorphism was investigated in 163 SIDS cases, 34 cases of infectious death and 121 controls, using real‐time PCR and fluorescence melting curve analysis. Results: There were no differences in val66met genotype distribution between neither the SIDS cases nor the cases of infectious death and controls (p = 0.95 and p = 0.52, respectively). Conclusion: The study indicates that the val66met polymorphism is not important for sudden unexpected infant death. However, several other SNPs in the BDNF gene, as well as in other genes involved in this pathway, including G‐protein, have to be investigated to fully exclude any involvement of BDNF in SIDS.  相似文献   
22.
田维才  刘波  涂哲明  蔡德明  邓小鹏 《中国民康医学》2007,19(23):1011-1012,1015
目的:评价国产利培酮(索乐)治疗精神分裂症的疗效和安全性。方法:通过对全国45家精神病医院的962例精神分裂症患者进行多中心,大样本,开放性的为期8周的治疗观察。采用PANSS、CGI、SAS和TESS评定疗效和不良反应。结果:国产利培酮(索乐)对精神分裂症总有效率84.3%,临床总体疗效肯定,不良反应轻,主要是轻度的锥体外系反应,体重增加,因其程度轻,病人基本能耐受。结论:国产利培酮(索乐)对精神分裂症阳性症状及阴性症状均有效,起效快,安全性高,患者对该药依从性好,可作为精神分裂症的首选药物之一。  相似文献   
23.
To determine the role of human papillomavirus (HPV) in the etiology of sinonasal papillomas, 57 inverted papillomas including 5 cases associated with carcinomas, 16 exophytic papillomas, and 5 cases of columnar cell papillomas were examined for the presence of HPV DNA by in situ hybridization and polymerase chain reaction (PCR). The genetic studies were performed on the formalin-fixed, paraffin-embedded material. In only 6% of the 52 benign inverted papillomas was HPV DNA identified, whereas 69% of the exophytic papillomas were infected by HPV DNA. In none of the 5 cases with columnar cell papillomas could HPV be demonstrated. HPV 6/11 was identified in all of these HPV-positive cases. In the carcinoma area, HPV was detected in 2 (1 HPV 6/11 and 1 HPV 18) of the 5 inverted papillomas associated with carcinomas. The findings confirm the presence of HPV DNA in sinonasal papillomas. The results also indicate that HPV 6/11 may be involved in the pathogenesis of, solely, exophytic papillomas. We found that in situ hybridization and PCR seem equally sensitive in detecting HPV in sinonasal papillomas.  相似文献   
24.
徐浩  丁勇 《现代医院》2002,2(3):49-50
<正> 暨南大学医学院第一附属医院,又名广州华侨医院,经过20年的发展已成为一所集医、教、研为一体的大型三级甲等医院。医院的科研发展始终坚持"以学科建设为基础,人才培养是关键"的科研办院思路,从建院初期以调入人才为主到目前的以人才引进为辅、培养人才为主,20年来培养了一批中青年学术带头人,形成了一批技术力量强大的学科群。从建院初期仅有眼科学、内科学(血液病专业)2个硕士学位授与点发展到现在拥有眼科学、内科学、妇产科学3个博士学位、14个硕士学位授权点,1998年还被国家教委批准为临床医学专业学位授与点的试点单位。在各类学术期刊上发表文章3089篇,主编及参与编写171部专著,承担各级科研课题695项,获国家科技进步奖1项,省部级成果奖25项,厅局级科技进步奖69项,获专利9项。医院在培育科研优势的同时更注意发挥学科优势促进学科的发展。  相似文献   
25.
Although the concept of the sentinel node has existed for most of the twentieth century, it was only in the last decade that methods were developed which allowed practical application to cancer patients. Sentinel nodes (SN) are a highly variable but limited set of lymph nodes first to receive drainage from any given location. Cancer metastasizes to these nodes before other nodes. Radioactive tracers and blue dyes are used to guide the surgeon to the SNs for resection. Two large clinical trials of SN surgery in breast cancer patients are actively underway in the United States. Until the impact of this very promising technology is confirmed to provide the same staging and prognosis, regional control, and survival as conventional surgery, it is considered an experimental procedure.  相似文献   
26.
The selective delivery of therapeutic agents to tumor site without harming rest of the body is a major challenge in clinical oncology today. Phage display approach has been used for searching ligands for cell-surface macromolecules on cancer cells so that they can be employed as drug targeting agents. Although basic protocols for biopanning cells are available, they are not as such suitable for screening highly complex and diverse target as whole tumor. Present study is an attempt to select peptide ligands specific to whole tumors. The cells from freshly collected human breast tumors were biopanned with phage displayed disulfide-constrained random heptapeptide library, following subtraction on normal human breast cells. Comparative analysis of amino acid frequencies in tumor-selected peptides and in random peptides from unselected library showed that selection was not random. The binding assessment of tumor-selected clones, using highly sensitive chemiluminescence ELISA, demonstrated that 47-75% of selected clones, depending on a tumor, bound to tumor cells they were panned on. Furthermore, several clones bound exclusively or preferentially to tumor cells in comparison to normal breast cells. It was interesting to note that insert sequences of tumor-binding clones from different tumors shared significant motifs. It shows the possibility of identifying ligands that may bind to tumor-specific targets common in certain tumors. The results of this investigation on seven human breast tumors demonstrated that, using procedures developed in the present study, whole tumors can be panned successfully with phage displayed library and tumor-binding ligands can be identified rapidly in high throughput manner. This is an important enabling step in identifying lead molecules for developing novel, specific, and effective agents that can be used for the diagnosis and treatment of cancer.  相似文献   
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29.
Mechanical properties of the human posterior lens capsule   总被引:2,自引:0,他引:2  
PURPOSE: To investigate mechanical properties of the human posterior lens capsule. METHODS: Twenty-five human donor eyes were obtained from an eye bank. The age of the donors ranged from 1 to 94 years. Test specimens were prepared as tissue rings from posterior lens capsules by means of excimer laser. Capsular thickness was measured microscopically as the difference in focus between microspherules placed on the outer and inner surfaces of the capsule. The capsular rings were slipped over two pins connected to a motorized micropositioner and a force transducer and stretched at a constant rate with continuous recording of load and deformation. Data for the posterior lens capsule were compared with previously published data for the anterior lens capsule. RESULTS: The thickness of the posterior lens capsule ranged from 4 to 9 micro m and showed no significant changes with age. Ultimate mechanical strength of the posterior lens capsule decreased significantly with age. Ultimate strain ranged from 101% to 34%, ultimate load ranged from 15.9 to 1.1 mN, ultimate stress ranged from 16.1 to 1.1 N/mm(2), ultimate elastic stiffness ranged from 52.1 to 5.7 mN, and ultimate elastic modulus ranged from 27.4 to 3.3 N/mm(2). The load-strain and the stress-strain relationships in the posterior lens capsule were nonlinear, and therefore elastic stiffness and elastic modulus varied as a function of strain. In the low-strain region (0%-10% strain), elastic stiffness and elastic modulus ranged between 0.3 to 2.4 mN and 0.3 to 2.3 N/mm(2), respectively, and seemed to increase during the first part of life until middle age. CONCLUSIONS: Mechanical strength of the posterior lens capsule was found to decrease markedly with age. The age-related loss of mechanical strength seemed to begin earlier in the posterior lens capsule than in the anterior lens capsule. In accommodative function range (low strains), the mechanical quality of the posterior lens capsule was similar to the anterior lens capsule, which indicates that the mechanical effectiveness of the lens capsule in situ varies proportionally with capsular thickness.  相似文献   
30.
Mechanical properties of the human lens capsule   总被引:4,自引:0,他引:4  
The human lens capsule has recently been the subject of much attention in an attempt to understand its physiological function in relation to the accommodative function, its functional reserve in the elderly population, and its potential in relation to cataract surgery. This overview presents our current knowledge of the mechanical properties of the human lens capsule, discussed on basis of its structure and its role in accommodation and cataract surgery.  相似文献   
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