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101.
论述国内外微生物凝固天然胶乳的研究历程,并对其凝固特点进行比较分析;着重探讨影响微生物凝固的因素以及对天然橡胶的硫化性能影响;指出问题所在,对其前景进行展望。  相似文献   
102.
The characteristics of granules of heterotrophic and autotrophic bacteria were studied. The autotrophic granules were characterized by smaller granule size, higher density, higher concentration of extracellular polymeric substances (EPS) and weaker strength compared with the heterotrophic ones. The diameter and density of autotrophic granules were changed in the same fashion, resulting in stable granules, and the heterotrophic granule, however, grew up with the increase of diameter and the decrease of density. According to the strength analysis, it is proposed that in the autotrophic system, the balance between EPS and porosity is the main reason for the long term stability. However, the balance could not be obtained in the heterotrophic system and that the operational conditions could not control the overgrowth of filamentous bacteria was the reason for the instability.  相似文献   
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Protein-losing enteropathy (PLE) is known to induce hypercoagulability and resultant thromboembolism in dogs. We hypothesized that hypercoagulability would improve if remission was obtained in dogs with PLE after treatment. This study aimed to evaluate the changes in the coagulation parameters after treatment in dogs diagnosed with PLE. As coagulation parameters, prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen, thrombin-antithrombin complex (TAT), D-dimer, and antithrombin (AT) were measured. In addition to these parameters, rotational thromboelastometry (ROTEM), which evaluates the comprehensive coagulation and fibrinolysis reactions of whole blood, was conducted and the data of clotting time (CT), clot formation time (CFT), α angle (α), maximum clot firmness (MCF) and lysis index at 60 min (LI60) were obtained. Eleven of the 14 dogs diagnosed with PLE were classified as responders to the treatment based on the changes in their plasma albumin (ALB) concentration after treatment. Significant increase in CFT and decrease of α and MCF indicating the resolution of hypercoagulability were found after treatment in responder dogs; however, there was no significant change in the coagulation and fibrinolysis parameters other than those measured by ROTEM. This study demonstrated that the hypercoagulability detected by ROTEM was significantly improved after treatment in dogs with PLE.  相似文献   
106.
Coagulation profiles for marine fish were determined with the standard global screening assays, the prothrombin time (PT) and activated partial thromboplastin time (APTT) using homologous tissue thromboplastin and phospholipid extracts to investigate species-specificity of brain thromboplastins, and to establish a base-line coagulation profile for marine fish of economical importance for Mediterranean aquaculture (sea bream, Sparus aurata, sea bass, Dicentrarchus labrax, red porgy, Pagrus pagrus, common dentex, Dentex dentex). Sea bass and sea bream displayed the shortest PT (9.0–15.0 s) and APTT (22.1–35.8 s) in comparison to the other species (PT: 24.8–37.2 s, APTT: 39.6–66.4 s). Red porgy displayed the lowest fibrinogen value (1.2–2.3 g l–1), while no differences were found among the other species (2.2–2.8 g l–1). It is concluded that the interaction of the tissue factor and plasma clotting factor is relatively species specific and that the use of homologous brain extracts is preferable for haemostasis study in marine fish.  相似文献   
107.
对生物凝固法进行试生产,对比研究2种胶的6项性能,贮存时间对天然橡胶Po和PRI值的影响,并对影响生物凝固液及胶乳凝固效果的因素进行分析与讨论。结果表明:生物凝固胶的6项性能较好,生物凝固胶的Po值比甲酸凝固胶的Po值高,两种胶的PRI值较相似。从理论计算可看出,生物凝固直接费用比甲酸凝固直接费用每吨干胶可节约41~43.5元。  相似文献   
108.
笔者用中监所提供的猪丹毒标准株C#-(43)-2,6,7,8和自然野毒株作为菌种,经颈静脉接种100-500亿活菌/头,模拟急性猪丹毒DIC。试验猪34头,发病27头,死亡15头。发病猪生前凝血象出现变化;死后组织学检查,脑、肾、心、肺等器官有DIC形成。电镜观察微血栓为纤维素,红细胞和丹毒杆菌。本文对DIC判定标准,DIC病理组织学特点及其发病机制和意义进行了讨论。  相似文献   
109.
Based on analysis of the characteristic of the sludge, in this paper, three kinds of sludge were selected to make coagulant experiment with three different coagulants. The specific resistance to filtration is tested. Finally,the optimum coagulant with its optimum dosage is obtained and the dewatering effect is improved.  相似文献   
110.
Systemic mastocytosis, characterized by infiltration of multiple organs by neoplastic mast cells, is a well-described entity in human medicine with specific criteria for diagnosis, but is ill defined in veterinary literature. Hemostatic disorders are reported in humans affected by systemic mastocytosis but have not been well described in veterinary literature. A 5-y-old, spayed female Greyhound dog had a 1-mo history of progressive ventral cutaneous edema, hemorrhage, and pain. Cytology of an antemortem aspirate from the subcutis of the ventral abdomen was suggestive of mast cell neoplasia, but no discrete mass was present. The dog was euthanized and submitted for autopsy; marked subcutaneous edema and hemorrhage were confirmed. The ventral abdominal panniculus and dermis superficial to the panniculus carnosus were infiltrated by a dense sheet of neoplastic mast cells. The neoplastic cells contained toluidine blue–positive granules and formed aggregates within the bone marrow and several visceral organs, including the liver, spleen, heart, and kidney. Diffuse edema and hemorrhage is an unusual presentation of mast cell tumors in dogs. Antemortem tests, including complete blood count, coagulation profile, and viscoelastic coagulation testing, were suggestive of a primary hemostatic defect. We discuss here the diagnostic criteria used in humans, how these can be applied to veterinary patients, and the limitations of the current diagnostic framework.  相似文献   
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