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101.
The greater omentum was used to aid in the reconstruction of nonhealing wounds in five cats. In each cat the cause of the nonhealing wound could not be determined. A vascular omental pedicle was created at laparotomy by dividing the dorsal leaf of the omentum at its pancreatic attachments (four cats) or by dividing the ventral leaf at its gastric attachments (one cat). The pedicle was then passed through either the ventral or lateral body wall into the nonhealing wound via a subcutaneous tunnel. The wounds were closed over the omentum after local tissue mobilization. All the wounds healed uneventfully and have remained healed with a mean follow-up period of 2.5 years. Complications included intestinal herniation through a ventral midline exit hole (one cat), presumed abdominal fat herniation through a ventral abdominal exit hole (one cat) and seroma formation (one cat). All of the complications were treated successfully. The omentum should be considered a useful adjunct in the treatment of nonhealing wounds in cats.  相似文献   
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小麦雄性不育系绒毡层异常代谢与小孢子败育的关系   总被引:1,自引:0,他引:1  
【目的】研究小麦遗传型雄性不育系花药绒毡层降解及营养物质代谢,并揭示其与花粉败育的关系。【方法】以小麦S型1376不育系[(S)-1376(A)]及其保持系[(A)-1376(B)]为试材,在三核期分别用DAPI和KI-I2对花粉粒内淀粉积累进行染色观察;采用半薄切片技术对不育系(S)-1376和保持系1376绒毡层发育过程及多糖、脂类和蛋白等物质积累进行观察和比较;采用软件cellSens Entry和IPP 6.0分别计算图片中小孢子和绒毡层细胞的面积及分析各发育时期图像中的平均光密度值。【结果】与保持系1376比较,(S)-1376花粉粒被KI-I2染成浅黄色,表明三核期其花粉中无淀粉积累,花粉败育彻底;不育系(S)-1376绒毡层较保持系1376绒毡层细胞提前至四分体时期启动细胞程序化死亡(PCD)过程;不育系(S)-1376花粉核发育迟缓,大多发育至单核晚期停止分裂,仅少数可发育至二核期;(S)-1376小孢子在四分体时期和单核早期显著增大;绒毡层细胞在四分体时期也显著大于保持系1376绒毡层细胞。在(S)-1376花粉的发育过程中,除四分体时期外,其余各时期多糖含量(呈红色)均低于保持系对应的各发育时期,不育系(S)-1376绒毡层中多糖在四分体时期多于保持系,在单核早期显著降低。在花粉整个发育过程中,不育系(S)-1376花粉中被染成黑色脂类的含量明显低于保持系,不育系绒毡层中的脂类含量在各个时期也低于保持系。不育系(S)-1376小孢子母细胞四分体时期被染成蓝色的蛋白含量很高,但单核晚期显著降低;在绒毡层细胞中单核早期蛋白含量显著低于保持系,这可能暗示该时期保持系绒毡层开始启动降解。在花粉发育整个过程中保持系1376小孢子母细胞中四分体时期多糖和蛋白的含量都低于不育系(S)-1376,这可能与该时期不育系绒毡层提前降解需要大量的多糖和蛋白有关;单核晚期小孢子中的多糖、脂类和蛋白含量高于不育系,该时期是正常小孢子发育的关键时期,不育系中各种物质供应不足可能是导致花粉败育的主要原因。在二核期和三核期,不育系(S)-1376花粉营养细胞中大液泡不消失,细胞质内含物也不持续增加,淀粉粒、脂类等物质积累终止,最终导致小孢子内没有内含物的积累,呈空壳晶体状。【结论】小麦S型1376A不育系花药绒毡层提前降解所诱发的物质异常代谢,使小孢子在由单核晚期向二核期发育的过程中物质供应不足导致细胞核分裂异常,最终引起花粉败育。  相似文献   
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人和几种动物的遗传学研究显示,MC4R基因在体重和能量平衡调控中具有重要作用,但未见有关犬的MC4R基因多态性、MC4R基因与性状关系的研究报道。以123只成年Beagle犬为试验材料提取血液DNA,利用软件设计PCR引物,经PCR扩增、克隆和测序后,发现了一个新的MC4R基因单核苷酸多态性(single nucleotide polymorphism,SNP)。该多态性恰好产生了限制性内切酶EcoO109Ⅰ的位点多态性。利用PCR-RFLP方法,分析了Beagle犬家系的MC4R基因,并利用SPSS软件分析该多态性与犬体重的关系。结果分析显示:MC4R该多态位点对犬的体重影响不显著。尚需进一步分析MC4R基因的其他片段。  相似文献   
106.
赤霉素与小麦生理型雄性不育的关系   总被引:1,自引:0,他引:1  
为探究赤霉素与小麦生理型雄性不育的关系,以新型小麦化学杀雄剂SQ-1作为诱导剂,西农1376为材料,构建了西农1376不育和可育生理系,通过扫描电镜、荧光定量PCR、气相质谱等技术,研究了小孢子花粉形态、TaGAMYB和CYP709C1基因表达、硬脂酸和赤霉素含量和花粉育性。结果表明,化学杀雄剂SQ-1诱导的生理型雄性不育系花粉粒畸形,TaGAMYB和CYP709C1基因表达量显著下降,硬脂酸含量显著上升,赤霉素含量显著低于可育系。赤霉素对雄性不育系的育性有一定逆转效应。  相似文献   
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Objective To investigate factors associated with low vitamin D status of alpacas at pasture in southern Australia. Design A 2‐year survey of alpacas from two farms in South Australia and three in Victoria. Blood samples were collected from 20 to 30 alpacas on each farm on five occasions each year. Breed, gender, age and fleece colour of animals were recorded. Method Blood samples were assayed for plasma 2.5‐hydroxycholecalciferol (25‐OH D3) and plasma inorganic phosphorus (Pi). Data sets from 802 animal samples were analysed by multiple regression to determine variables associated with low vitamin D status of alpacas. The relationship between plasma 25‐OH D3 and plasma Pi was also investigated. Results Vitamin D status was significantly affected by month of sampling, with low values in late winter and high values in summer. Plasma vitamin D concentrations increased with age, were higher in alpacas with light fleeces than in those with dark fleeces and were also higher in the Suri than in the Huacaya breed. Plasma Pi concentrations were generally lower in alpacas with plasma 25‐OH D3 values < 25 nmol/L. Conclusions Young alpacas with dark fleeces are most at risk from vitamin D insufficiency in late winter in southern Australia. The present study indicates that plasma Pi values are not a reliable indicator of vitamin D status of alpacas as assessed by plasma 25‐OH D3 concentrations.  相似文献   
108.
AIMS: To describe results of a relative validation exercise using the three simulation models of foot-and-mouth disease (FMD) in use by the quadrilateral countries (QUADS; Australia, Canada, New Zealand, and United States of America; USA).

METHODS: A hypothetical population of farms was constructed and, following the introduction of an FMD-like disease into a single farm, spread of disease was simulated using each of the three FMD simulation models used by the QUADS countries. A series of 11 scenarios was developed to systematically evaluate the key processes of disease transmission and control used by each of the three models. The predicted number of infected units and the size of predicted outbreak areas for each scenario and each model were compared using the Kruskal-Wallis test. Agreement among the three models in terms of geographical areas predicted to become infected were quantified using Fleiss' Kappa statistic.

RESULTS: Although there were statistically significant differences in model outputs in terms of the numbers of units predicted to become infected, the temporal onset of infection throughout the simulation period, and the spatial distribution of infected units, these differences were generally small and would have resulted in the same (or similar) management decisions being adopted in each case.

CONCLUSIONS: Agreement among the three models in terms of the numbers of premises predicted to become infected, the temporal onset of infection throughout the simulation period, and the spatial distribution of infected premises provides evidence that each of the model developers are consistent in their approach to simulating the spread of disease throughout a population of susceptible individuals. This consistency implies that the assumptions taken by each development team are appropriate, which in turn serves to increase end-user confidence in model predictions.

CLINICAL RELEVANCE: Relative validation is one of a number of steps that can be undertaken to increase end-user confidence in predictions made by infectious disease models.  相似文献   
109.
AIM: To investigate the molecular mechanism of microRNA-21 (miR-21) in the regulation of Schwann cell proliferation following nerve injury. METHODS: The expression of miR-2l was detected by real-time PCR. Synthetic miR-21 mimic and its control were transfected into rat Schwann cells. CCK-8 assay was performed to evaluate the influence of miR-21 on the proliferation of Schwann cells. The cell cycle distribution was determined by flow cytometry. The expression of transforming growth factor β-induced protein (TGFBI) and cyclin D1 were detected by Western blotting. RESULTS: The expression of miR-21 in model group was 7.87±0.75 and 7.75±0.80 times higher than that in sham operation group and blank group respectively. After transfected with miR-21 mimic, the expression of miR-21 in experimental group was 2.21±0.14 and 2.29±0.21 times higher than that in negative control group and blank group respectively. Moreover, the A450 value of CCK-8 assay in experimental group at 48 h was higher than that in negative control group and blank group. The proliferation index in experimental group was higher than that in negative control group and blank group. At the same time, the expression of TGFBI obviously decreased and the cyclin D1 increased in the Schwann cells 48 h after transfection with miR-21. CONCLUSION: miR-21 promotes the proliferation activity of Schwann cells by down-regulating TGFBI expression.  相似文献   
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