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71.
地理信息系统应用于血吸虫病的监测 Ⅰ.应用预测模型的可能性 总被引:10,自引:7,他引:10
目的:建立血吸虫病地理信息系统,利用气象参数建立模型来探讨预测血吸虫病的流行区的可能性。方法:以世界粮农组织出版的FAOCLIM数据库中的数据为基础,以血吸虫发育扩散关系密切的温度和潜在蒸发指数(地面水平衡系统)为基础的改良Malone公式计算血吸虫传播指数,结合AVHRR卫星图片资料,获得校正植被指数(NDVI)和第4频道地面温度指数、高程分布图,在ArcView3.0a和ERDAS软件支持下,进行GIS数据空间分析和地图重叠分析,以某一类别值显示出流行区的地理分布图。结果:血吸虫传播指数(指数值大于900)的分布基本上与中国南部地区的血吸虫病流行区相吻合。多层重叠分布图显示了红色区域的高危地区与长江流域的血吸虫病高发地区基本一致。结论:血吸虫病的流行范围与温度、高程、雨量等因素密切相关。利用气象资料模型和卫星遥感资料对预测血吸虫病的潜在流行区具有可能。准确、快速地利用AVHRR遥感资料来预测、预报血吸虫病流行范围和强度具有应用前景,值得作进一步探讨。 相似文献
72.
Transverse Coloplasty Pouch After Total Mesorectal Excision: Functional Assessment of Evacuation 总被引:3,自引:0,他引:3
Köninger JS Butters M Redecke JD Z'graggen K 《Diseases of the colon and rectum》2004,47(10):1586-1593
PURPOSE Colon pouch reconstruction after total mesorectal excision is functionally superior to straight colorectal/anal anastomosis. In the long-term, stool evacuation difficulties could jeopardize the functional benefit. The transverse coloplasty pouch presents an alternative to the standard J-pouch. This study was designed to analyze functional outcome and defecography findings after total mesorectal excision and transverse coloplasty pouch reconstruction.METHODS Thirty consecutive patients with cancer of the middle and lower third of the rectum underwent a total mesorectal excision and were examined in a prospective study. In all patients, reconstruction was performed with a transverse coloplasty pouch. Pouch and anastomosis were checked by Gastrografin® enema postoperatively. Patients were examined within eight months by means of defecography, manometry, pouch volumetry, and a standardized continence questionnaire.RESULTS Total mesorectal excision with transverse coloplasty pouch anastomosis was performed successfully in all patients. Symptomatic anastomotic leakage was observed in 2 of 30 patients and the radiologic leak rate was 4 of 30. All patients evacuated the pouch completely; none needed enemas or suppositories to facilitate defecation. Twenty-five of 27 patients had a maximum of three bowel movements per day, and all patients were continent for solid stools. Patients with abnormal findings on defecography proved more likely to have anal dysfunction.CONCLUSIONS Transverse coloplasty pouch reconstruction after total mesorectal excision leads to good functional results and is not associated with stool evacuation problems. Urgency and incontinence correlate rather with impaired pelvic floor movement than with pouch size or anal sphincter tonus.Presented at the Congress: Rectal Cancer Treatment, Heidelberg, Germany, October 9 to 11, 2003.Reprints are not available. 相似文献
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75.
Human parvovirus B19-induced epidemic acute red cell aplasia in patients with hereditary hemolytic anemia 总被引:11,自引:1,他引:11
Saarinen UM; Chorba TL; Tattersall P; Young NS; Anderson LJ; Palmer E; Coccia PF 《Blood》1986,67(5):1411-1417
From March to August 1984, 26 patients with hereditary hemolytic anemia in northeastern Ohio developed acute, profound red cell aplasia. The patients included 14 males and 12 females 2 to 23 years old, with sickle cell anemia (20 cases), hemoglobin SC-disease (4 cases), sickle- beta-thalassemia (1 case), or hereditary spherocytosis (1 case). All had an acute onset of severe reticulocytopenia and anemia and prodromal symptoms of illness including fever, abdominal symptoms, headache, and arthralgias. Twenty-two received transfusions. Reticulocytosis occurred spontaneously within 2 to 14 days of presentation. In five acute-phase sera, 10(8) to 10(12) viral particles/mL were detected by electron microscopy. Human parvovirus B19 DNA was demonstrated in high concentration by hybridization in the same five acute-phase sera and in low concentration in sera of eight additional patients. The five highly viremic sera inhibited erythroid colony formation in vitro. B19- specific IgM was detected in sera of 24/26 patients, and B19-specific IgG in 21 of 22 patients tested. Our results indicate that human parvovirus B19 was the etiologic agent in this large epidemic of life- threatening acute red cell aplasia in patients with hereditary hemolytic anemia. 相似文献
76.
Interventional radiologic procedures in the renal transplant 总被引:1,自引:0,他引:1
Curry NS; Cochran S; Barbaric ZL; Schabel SI; Pagani JJ; Kangarloo H; Diament M; Gobien RP; Vujic I 《Radiology》1984,152(3):647-653
Percutaneous interventional procedures can be valuable in the evaluation and treatment of urologic complications of renal transplantation. Thirty-three patients underwent percutaneous procedures, including relief of obstruction by catheter nephrostomy, diagnostic antegrade pyelography with Whitaker testing, aspiration of various fluid collections (lymphocele, hematoma, urinoma, and abscess), and renal artery angioplasty, during a three year period at three institutions, to provide temporizing treatment and anatomic data. Surgical intervention was sometimes avoided, but more often it could be deferred to allow the patient to stabilize prior to surgery. Complications that required surgery occurred in two patients. 相似文献
77.
78.
C J Edge T W Rademacher M R Wormald R B Parekh T D Butters D R Wing R A Dwek 《Proceedings of the National Academy of Sciences of the United States of America》1992,89(14):6338-6342
A method of oligosaccharide analysis involving controlled fragmentation resulting from enzymatic digestion is presented. The principle involves generating a set of fragments from the original oligosaccharides, characterizing them in terms of their hydrodynamic volumes, determining their molar proportions, and identifying the oligosaccharides by comparison with a computer-generated data base. Experimentally, this technique involves incubation of aliquots of a sample with a set of defined mixtures of exoglycosidases followed by pooling of the products and a single analysis on the product pool. This method has several practical advantages over current techniques, including speed and the ability to use smaller amounts of starting material. The detection of the intensity-versus-hydrodynamic volume profile is limited only by the specific activity of the labeling method. The ability to perform the enzyme digestions is limited by the individual Km values of the enzymes. 相似文献
79.
Several initiatives have been introduced over the years to address the maldistribution of health care professionals and to improve access to care for underserved rural populations. One of these is the sponsorship of community-based, service-oriented teams comprised of students from various health disciplines. This study investigated extramural training as a complement to traditional hospital-based experiences. The specific objective of the study was to determine the extent to which the nation's medical schools combine training with a rural community-based experience in the form of an interdisciplinary student health team program. In the fall of 1994, a 32-item questionnaire was mailed to the chief academic or clinical affairs administrators of the nation's 126 allopathic medical schools. A total of 104 (82.5%) medical schools responded to the survey. Eighty-six of the respondents (82.7%) reported some type of rural training or public service activity; 22 (21.2%) acknowledged the sponsorship of an interdisciplinary student health team program. Small rural communities, those with populations of 5,000 or fewer, were the focus of 76 percent of the reporting programs. Nearly two-thirds of the reporting programs were located in the South, the region with the nation's lowest physician-to-population ratio. The nursing and medical professions were most frequently represented, although a wide range of disciplines were identified as participating on the student health teams. Activities of the teams included both ambulatory care and community outreach services. The majority of the programs used team-building exercises to enhance team effectiveness. Extramural training programs offer students a realistic examination of the social, cultural, economic, and political forces that influence both individual and community health. Rural community-based programs, such as interdisciplinary student health teams, should be valued because they can strengthen the link between the sponsoring institution's educational mission and its public service obligation. 相似文献
80.
Granulocyte-macrophage colony-stimulating factor mRNA stabilization enhances transgenic expression in normal cells and tissues 总被引:3,自引:1,他引:2
To increase transgenic production of granulocyte-macrophage colony- stimulating factor (GM-CSF), we mutated the mRNA's 3'-untranslated region, AUUUA instability elements. Expression vectors containing human or murine GM-CSF cDNAs coding for wild-type (GM-AUUUA) or mutant versions with reiterated AUGUA repeats (GM-AUGUA) were transfected into cells in culture or animals using particle-mediated gene-transfer technology. Normal peripheral blood mononuclear cells accumulated 20- fold greater levels of GM-CSF mRNA and secreted comparably greater amounts of cytokine after transfection with hGM-AUGUA expression vectors versus hGM-AUUUA. hGM-AUGUA mRNA was fivefold more stable (t 1/2 = 95 minutes) than hGM-AUUUA mRNA (t 1/2 = 20 minutes), accounting for elevated steady-state levels. Transfection site extracts and serum samples obtained 24 hours after gene transfer of hGM-AUGUA cDNA into mouse skin contained greater than 32 ng/mL and 650 pg/mL of GM-CSF protein, respectively, compared with 0.33 ng/mL and less than 8 pg/mL for hGM-AUUUA cDNA. GM-CSF produced from mGM-AUGUA cDNA transfected into rat abdominal epidermis induced a profound neutrophil infiltrate. These data suggest a novel strategy for enhanced production of biologically active cytokines by normal cells after in vivo gene transfer. 相似文献