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胃肠胰胰岛淀粉样多肽的定位和表达   总被引:2,自引:3,他引:2  
胰岛淀粉样多肽(islet armyloid polypeptide,IAPP)是1986年瑞典学者Westermarket al[1,2 ]从胰岛素瘤患者的瘤组织,糖尿病猫及Ⅱ型糖尿病患者胰岛淀粉样沉积物中分离出来的一种多肽,几乎在同时,英国生物化学家Cooper et al[3,4]也从Ⅱ型糖尿病患者的胰岛淀粉样沉积物中分离出该肽.IAPP又称为amylin.对IAPP的分子结构、基因表达和生理作用等已有许多报道[5].近年来,在IAPP定位、表达及胃肠胰IAPP免疫反应(immunoreactive,IR)细胞定位、发生、发育方面的研究报道,为探讨IAPP的生理作用及疾病状态下的改变,提供了形态学依据,现综述如下.  相似文献   
14.

Background

Road traffic injuries (RTI) are on increase in developing countries. Health care facilities are poorly equipped to provide the needed services.

Objective

Determine access and quality of care for RTI casualties in Kenya.

Design

Cross-sectional survey

Setting

53 large and medium size private, faith-based and public hospitals.

Participants

In-patient road traffic crash casualties and health personnel in the selected hospitals were interviewed on availability of emergency care and resources. Onsite verification of status was undertaken.

Results

Out of 310 RTI casualties interviewed, 72.3%, 15.6% and 12.2% were in public, faith-based and private hospitals, respectively. Peak age of the injured was 15–49 years. First aid was availed to 16.0% of casualties. Unknown persons transported 76.5% of the injured. Police and ambulance vehicles transported 6.1% and 1.4%, respectively. 51.9% reached health facilities within 30 minutes of crash and medical care provided to 66.2% within one hour. 40.8% of recipient facilities were adequately prepared for RTI emergencies.

Conclusions

Most RTI casualties were young and from poor backgrounds. Training of motorists and general public in first aid should be considered in RTI control initiatives. Availability of basic trauma care medical supplies in public health facilities was highly deficient.  相似文献   
15.
Localization of vital components of neurological functioning has to be performed before epilepsy surgery can be considered in children with intractable epilepsy. This study reports the experience with the Wada procedure in very young children and/or developmentally delayed children with an a priori considerable chance of failing the procedure. The aim of this study was to indicate the applicability of this procedure in this patient group. The Wada procedure is described in 16 children under 10 years of age and/or have intelligence quotient scores below 50 and/or are critically ill and/or are behaviourally disturbed. Information on motor, language and memory functioning is obtained in respectively 13/15, 9/13, and 5/11 children. Nine children underwent epilepsy surgery without postoperative impairment of neurological functioning. In five children epilepsy surgery was not performed because of the results of the Wada procedure or the lack of information during the Wada procedure. One child became seizure-free before surgery. Even in very young, developmentally delayed or behaviourally disturbed children, the Wada test can provide important information with respect to the decision pro or contra epilepsy surgery.  相似文献   
16.
Controlling the sex of offspring by the separation of X and Y chromosome-bearing spermatozoa using flow cytometry has been reported as a clinical technique aiding prevention of X-linked diseases. Although this technique has resulted in several hundred normal births in animals and at least one human birth, there is still concern over its genetic safety due to the involvement of two potentially mutagenic agents: UV light and the fluorochrome dye, Hoechst 33342 (H33342). Human spermatozoa, particularly those considered abnormal, may be more likely to suffer DNA damage following exposure to mutagenic agents, compared with other mammalian species. The stability of normal fresh and decondensed human spermatozoa were examined after exposure to a range of levels of UV and H33342 staining, using an assay that detects endogenous nicks in the DNA of spermatozoa. The stability of abnormal and normal, fresh and frozen-thawed human spermatozoa was examined following UV laser, H33342 staining and flow cytometry treatments utilizing the same assay. There was an increase in the presence of endogenous nicks when spermatozoa were decondensed compared with fresh spermatozoa. There was no increase in the incidence of nicks in any group of spermatozoa after UV and fluorochrome exposure compared with controls without exposure.   相似文献   
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Freeny  PC; Marks  WM 《Radiology》1986,160(3):613-618
Bolus dynamic and delayed computed tomographic (CT) scans of the liver were evaluated in 43 patients with 54 hepatic hemangiomas and 111 patients with primary or secondary malignant hepatic neoplasms. Twelve patterns of contrast enhancement were recognized during the bolus dynamic phase and delayed scanning. A "typical" CT pattern for hemangiomas (present in 29 of 54 hemangiomas [53.7%]) was established: (a) diminished attenuation prior to intravenous contrast medium administration (excluding lesions arising in a liver with diffuse fatty infiltration), (b) peripheral contrast enhancement during the bolus dynamic phase, and (c) complete isodense fill-in on delayed scan images. Using these criteria, we distinguished hemangiomas from malignant neoplasms in most patients. Only one of 63 (1.6%) malignant neoplasms manifested these typical CT criteria of hemangioma. There is an 86% chance that a lesion with the typical CT appearance of hemangioma is actually a hemangioma, even when found in a patient with a known nonhepatic primary neoplasm.  相似文献   
20.
Aims. This article aims to review the literature published to date on the types, current use, the biomechanical effects and adverse effects of maternity support belts for low back pain during pregnancy, to identify future research directions. Background. Lumbar/pelvic support belts are frequently recommended for the prevention and treatment of low back pain during pregnancy. Design. Systematic review. Methods. MEDLINE, CINAHL, the Cochrane Library and patents databases were electronically searched. Results. Maternity support belts belong to one of the four main types of maternity support garments, which are widely commercially‐available. Current research showed limited evidence in support of the commercial maternity products regarding the effectiveness in the prevention and/or treatment of low back pain during pregnancy, other than that from the manufacturers. However, potential stabilisation effect of maternity support belt was demonstrated in some studies. Adverse effects reported include increased pain, fetal heart rate changes, skin irritation and discomfort. Conclusions. There is insufficient scientific evidence to conclude that wearing maternity support belts reduces pregnancy‐related low back pain and/or pelvic girdle pain. Future research directions in the area of biomechanics and physiology are recommended. Relevance to clinical practice. This review provides comprehensive understanding of the effectiveness of maternity support belts for the relief of low back pain during pregnancy which will facilitate healthcare professionals in providing evidence‐based advice to their patients.  相似文献   
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