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951.
针对一类二维加权积分的数值计算方法及误差分析进行研究,参照一维广义高斯积分数值求积方法提出一种具有较高代数精度的计算方法并对其误差做分析,同时给出几个简明的结果。这些结果可用到诸如小波分解,图像处理与多分辨数字信号处理等领域。 相似文献
952.
刘强 《湖南农业大学学报(自然科学版)》2007,(4)
对电影作品的网络"恶搞"是我国网络产业发展的新产物,在形式和内容上都有其显著特点。网络"恶搞"能够迅速流行有深刻的文化和技术背景。从性质上说,网络"恶搞"属于新型文艺评论,也具备构成改编作品的条件。网络"恶搞"在网络的传播可能对电影作品的著作权、相关主体的名誉权和肖像权构成侵犯,尽管如此,我们应当在保护公民言论自由的基础上寻求对其进行规制。 相似文献
953.
上海松江中心城区道路绿化类型及景观分析 总被引:2,自引:0,他引:2
将松江中心城区道路绿化的配置形式归纳为14个类型,并对各类型的绿化景观效果进行了分析。 相似文献
954.
DB102为一田间发现的三倍体水稻,利用它做母本与二倍体水稻中作59杂交,得到一个早世代(F2)稳定群体,通过微卫星分析发现,该群体中有一些微卫星位点发生了杂合性丧失,且至少6条染色体上发生微卫星位点杂合性丧失(loss of heterzygoisity LOH)可能有DNA序列变化。而微卫星位点的杂合性丧失又可能与该杂交组合早世代稳定有关。 相似文献
955.
对北京市新型农村合作医疗制度的调查与思考 总被引:1,自引:0,他引:1
李香允 《北京农业职业学院学报》2007,21(5):53-57
自2002年7月北京市大兴区率先在全国开展新型合作医疗试点至今,北京市新型农村合作医疗制度运行已经5年了.在对北京市新型农村合作医疗制度运行情况进行充分调研的基础上,总结了所取得的成效,分析了存在的问题,要进一步完善这项制度应提高筹资水平,实行动态缴费;提高补偿水平,提升制度吸引力;充实管办资源,重视调研能力建设等. 相似文献
956.
采用柠檬酸法合成出超微W型铁氧体。用XRD、VSM测试其结构和磁性能。试验结果表明,该法在1000℃制得的铁氧体性能优于其他方法制得的铁氧体,控制pH值、水量和柠檬酸的量对铁氧体的结构和磁性能都有一定的影响。 相似文献
957.
Objective To improve the isolation rate and identification procedures for Haemophilus parasuis from pig tissues. Design Thirteen sampling sites and up to three methods were used to confirm the presence of H. parasuis in pigs after experimental challenge. Procedure Colostrum‐deprived, naturally farrowed pigs were challenged intratracheally with H parasuis serovar 12 or 4. Samples taken during necropsy were either inoculated onto culture plates, processed directly for PCR or enriched prior to being processed for PCR. The recovery of H parasuis from different sampling sites and using different sampling methods was compared for each serovar. Results H parasuis was recovered from several sample sites for all serovar 12 challenged pigs, while the trachea was the only positive site for all pigs following serovar 4 challenge. The method of solid medium culture of swabs, and confirmation of the identity of cultured bacteria by PCR, resulted in 38% and 14% more positive results on a site basis for serovars 12 and 4, retrospectively, than direct PCR on the swabs. This difference was significant in the serovar 12 challenge. Conclusion Conventional culture proved to be more effective in detecting H parasuis than direct PCR or PCR on enrichment broths. For subacute (serovar 4) infections, the most successful sites for culture or direct PCR were pleural fluid, peritoneal fibrin and fluid, lung and pericardial fluid. For acute (serovar 12) infections, the best sites were lung, heart blood, affected joints and brain. The methodologies and key sampling sites identified in this study will enable improved isolation of H parasuis and aid the diagnosis of Glässer's disease. 相似文献
958.
Zandvliet MM Rothuizen J 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(2):215-218
BACKGROUND: Irish Wolfhounds frequently have a congenital portosystemic shunt, but a considerable proportion of the 6- to 8-wk-old pups has hyperammonemia in the absence of portosystemic shunting. This hyperammonemia causes no signs and is transient, normalizing at the age of 3-4 months. HYPOTHESIS: Transient hyperammonemia has a metabolic basis in Irish Wolfhounds. ANIMALS: Two related (same sire) litters of Irish Wolfhounds (17 pups) and their parents were studied. METHODS: Integrity of the portal circulation was examined by ultrasonography and scintigraphy. Absence of parenchymal liver disease was verified by liver biopsy. Amino acid profiles were measured in 4 pups and repeated in 2 of these pups when ammonia concentrations had normalized. The amino acid profiles were compared with those of healthy Irish Wolfhound pups. RESULTS: Fasting venous ammonia concentrations were high (113-622 microg/dL, 65-345 micromol/L) in all pups, whereas bile acids were within reference range in all but 1. The ammonia and bile acid concentrations from all parents were within reference range. Portosystemic shunting was excluded in all but 1 pup. Liver biopsy excluded significant lesions in all 10 pups examined. Hypercitrullinemia was found and persisted even when ammonia had normalized, at the expense of an increase in glutamine and asparagine. CONCLUSIONS AND CLINICAL IMPORTANCE: Citrulline concentrations are controlled by the urea cycle enzymes argininosuccinase and argininosuccinate synthetase, and a defect in either of these enzymes may be responsible for the transient hyperammonemia in Irish Wolfhounds. Resolution of the hyperammonemia is associated with increased activity of alternative metabolic pathways forming glutamine and asparagine. Confirmation requires measurement of enzyme activities in liver tissue. 相似文献
959.
Goldstein RE Atwater DZ Cazolli DM Goldstein O Wade CM Lindblad-Toh K 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(1):199-203
BACKGROUND: Primary hyperparathyroidism (PHPT) is caused by inappropriate secretion of parathyroid hormone (PTH) by autonomously functioning neoplastic or hyperplastic parathyroid "chief" cells. Keeshonden are thought to be over-represented in studies on canine PHPT, but no proof of heritability or mode of inheritance has been published. The canine disease clinically resembles human familial isolated hyperparathyroidism (FIHP). HYPOTHESIS: Primary hyperparathyroidism in Keeshonden is genetically transmitted and is caused by a mutation in 1 of 4 genes implicated in human FIHP: MEN1, CASR, HRPT2, or RET. ANIMALS: Pedigrees consisting of 1647 Keeshonden were created including 219 Keeshonden with known PHPT phenotypes (69 positive). DNA samples were obtained from 176 of the 219 Keeshonden (34 positive). METHODS: Heritability and mode of inheritance were determined by segregation analysis. Canine homologs to the human genes were identified. Exons and surrounding intron regions were sequenced and scanned for sense-altering polymorphisms or polymorphisms that segregated with the disease. Messenger RNA from a parathyroid tumor of an affected Keeshond was analyzed for polymorphisms and splice alterations. RESULTS: PHPT follows an autosomal dominant mode of inheritance in Keeshonden with possible age-dependent penetrance. No polymorphisms identified in the genes analyzed were associated with a change in predicted protein or in hypothesized splice sites. CONCLUSIONS AND CLINICAL IMPORTANCE: PHPT is an autosomal dominant, genetically transmitted disease in Keeshonden. Once the mutation locus is identified, genetic testing should quickly decrease the incidence of PHPT in this breed. It is unlikely that mutations in MEN1, CASR, HRPT2, or RET cause PHPT in Keeshonden. 相似文献
960.
Adin DB Diley-Poston L 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(4):737-741
BACKGROUND: Papillary muscle hypertrophy can occur in conjunction with, or as the only indication of, hypertrophic cardiomyopathy or other diseases that result in left ventricular concentric hypertrophy (LVCH). Assessment of papillary muscle size is usually subjective because objective measures have not been reported. HYPOTHESIS: The study hypothesis was that papillary muscle dimensions are different between normal cats and cats with LVCH. ANIMALS: Echocardiograms from 44 normal cats and 40 cats with LVCH were included in the study. METHODS: All measurements were taken from the right parasternal short-axis view at the level of the papillary muscles at end-diastole. Three methods were used to assess papillary muscle size: the area subtraction method, the direct area trace method, and the diameter method. Measurements were compared between cat groups and method comparisons were made among methods for area determination. RESULTS: Cats with LVCH were older and had significantly greater left ventricular septal and free wall thicknesses and larger left atrial measurements than normal cats (P < .0006). Papillary muscle measurements were significantly greater by all measurement methods in cats with LVCH than in cats with normal echocardiograms (P < .0001). The area subtraction method and direct area trace method showed moderate agreement. CONCLUSIONS AND CLINICAL IMPORTANCE: Papillary muscle measurements were larger for LVCH cats than normal cats; however, some overlap was present. The establishment of these objective measures adds to the echocardiographic examination of cats. 相似文献