Molecular and chemical neuropathology - Changes in the functioning of the glutamatergic system in rabbit brain were studied after partial brain ischemia and reperfusion. In vitro studies were... 相似文献
Summary: The morphology of the transcrystalline layer grown by nucleating high density polyethylene on fibers of ultra high molecular weight polyethylene was investigated by microbeam synchrotron X‐ray diffraction. Scanning with a 2 micron step size, it was possible to determine that near the fiber surface, the polymer chains of the transcrystalline layer are oriented at an angle of approx. 41° with respect to the fiber axis. This is consistent with the lamellar fold surface (the {201} plane) being close to perpendicular to the fiber axis. The X‐ray data support gradual twisting of the lamellae about the growth direction (the orthorhombic crystallite b‐axis) at a rate of ~0.85° per micron of radial distance from the fiber surface.
Polarized light micrograph of the transcrystalline layer in a PE/PE composite. The width of the fiber is approximately 20 μm. 相似文献
Mutations in the MYOC gene may lead to juvenile open-angle glaucoma with high intraocular pressure, and are detected in about 4% of people with adult onset glaucoma. Most of these mutations are found in the third exon of the gene encoding the olfactomedin-like domain located at the C terminus of the protein. Another olfactomedin-related protein, known as noelin or pancortin, is involved in the generation of neural crest cells. Here we describe the identification of a novel olfactomedin-related gene, named optimedin, located on chromosome 1p21 in humans. Optimedin and noelin are both expressed in brain and retina. However, unlike noelin, rat optimedin is also highly expressed in the epithelial cells of the iris and the ciliary body in close proximity to the sites of Myoc expression. In the human eye, optimedin is expressed in the retina and the trabecular meshwork. Both optimedin and myocilin are localized in Golgi and are secreted proteins. The presence of mutant myocilin interferes with secretion of optimedin in transfected cells. Optimedin and myocilin interact with each other in vitro as judged by the GST pulldown, co-immunoprecipitation and far-western binding assays. The C-terminal olfactomedin domains are essential for interaction between optimedin and myocilin, while the N-terminal domains of both proteins are involved in the formation of protein homodimers. We suggest that optimedin may be a candidate gene for disorders involving the anterior segment of the eye and the retina. 相似文献
Interactions between the carbonyl and amino groups in copolymers of 2-dimethylaminoethyl methacrylate with N-phenylmaleimide are reported. The existence of interactions ensues from potentiometric measurements and UV-VIS spectra. Interactions in these copolymers result in the formation of energetically very advantageous chromophores, reflected in an intense red colour of the substances obtained. 相似文献
Primary genetic factors are etiologic in at least 5-10% of patients with colon cancer. The polyposis syndromes (FPC) are easily identified examples because of the spectacular number of polyps. The hereditary nonpolyposis syndromes (HNPCC), although five times more common than FPC, are usually not recognized because they do not have such a distinctive clinical, premonitory genetic marker. Colorectal cancer expression was surveyed in 10 extended, thoroughly documented HNPCC kindreds. One hundred sixteen patients were found to have 183 colorectal cancers. Despite the striking family history, less than 5% were correctly treated by subtotal colectomy. This provided a unique opportunity to study the natural history. Five findings differed significantly (p less than 0.05) from patients with sporadic colon cancer: (1) mean age of initial colon cancer diagnosed was 45.6 years; (2) 69.1% of first colon cancers were located proximal to the splenic flexure of the colon; (3) 18.1% had synchronous colon cancer; (4) 24.2% had metachronous colon cancer develop with life table analysis showing the risk for a metachronous lesion at 10 years to be 40%; and (5) only 23.3% of cancers were located in the sigmoid colon or rectum. Based on this data, it is recommended that the family history of all patients with a newly diagnosed colon cancer be evaluated for evidence of this syndrome. If an autosomal dominant inheritance pattern emerges, an in-depth genetic investigation is indicated. When HNPCC is confirmed, the following recommendations apply: a subtotal abdominal colectomy is indicated at the time of the initial colon cancer because of the risk of synchronous and metachronous lesions. The rectum should be spared in favor of careful lifetime surveillance because of the proclivity for proximal colon cancer involvement. As yet unaffected members of a newly diagnosed HNPCC kindred who are in the "direct genetic line" should be cautioned that they are at 50% risk and must begin an intensive surveillance program beginning in the third decade with careful attention to the right colon. Patients from newly diagnosed HNPCC families who have had a previous conventional colectomy for colon cancer should, at the very least, enter an intensive surveillance program; a prophylactic completion subtotal colectomy should be considered for patients who are less than totally compliant. 相似文献
This review brings together studies dealing with factors that affect participation in screening, referral, and treatment for high blood pressure (HBP). Community-based screening programs are examined first, in order to describe the changing and the current distribution of hypertensives as unaware, untreated, treated but uncontrolled, and controlled by treatment. Factors influencing this distribution are examined. Next, data on referral, acceptance of treatment, and staying in treatment are discussed, with a special reference to intervention studies. The review then brings in the broader social science literature on the psychosocial dynamics of health-maintaining and risk-reducing behaviors. The article concludes with an interpretive summary and some suggestions for further action. 相似文献