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141.
The presence of a malignant mixed tumor, also known as a carcinosarcoma, in the salivary gland is very rare. Such tumors, which are typically aggressive, are characterized by the presence of carcinomatous and sarcomatous components. A 9-year-old neutered female domestic short-haired cat presented with swelling in the right mandibular lesion that had rapidly enlarged over the previous 3 weeks. Physical examination revealed a large, fluctuated and painless subcutaneous swelling that was associated with a firm mass. Radiographs of the head revealed a soft-tissue density that involved faint circular calcific opacity. Contrast-enhanced computed tomography revealed that the peripheral capsulated cystic area had a contrast enhanced region without bone lysis. The cat received a total excision of the mass and postoperative radiotherapy. Histopathological analysis of the mass revealed that it was a malignant mixed tumor. Metastasis to the lung was discovered 7 weeks later, at which time treatment was stopped.  相似文献   
142.
为了探索鹿角盘(DHAB)水提物对大鼠乳腺增生的治疗作用,初步探讨其作用机理和用药剂量,试验利用苯甲酸雌二醇(0.5 mg/(kg·d))联合黄体酮(5.0 mg/(kg·d))对SD大鼠进行肌内注射建立乳腺增生模型。试验共分7个组,每组10只大鼠,分别为空白组、乳腺增生症(HMG)模型组、阳性药三苯氧胺组(0.036 mg/(kg·d))、鹿角盘水提物4个剂量组(高剂量,2.625 g/(kg·d);中高剂量,1.575 g/(kg·d);中低剂量,1.05 g/(kg·d);低剂量,0.63g/(kg·d))。按组别连续灌胃45 d,每周固定时间测定大鼠乳头直径、高度及体重。试验结束后采血取样,称量大鼠胸腺、脾脏、子宫和卵巢质量,取乳腺组织做病理学切片、HE染色,用放射免疫法检测大鼠血清中雌二醇(E2)及孕酮(P)的含量。结果表明,使用不同剂量鹿角盘水提物均能减小乳腺增生大鼠乳头直径、高度,提高胸腺、脾脏指数,降低子宫指数,减轻乳腺小叶数、腺泡数和分泌物,降低血清E2含量,升高血清P的含量,与模型组相比有统计学差异(P < 0.01;P < 0.05))。综合试验结果,鹿角盘水提物对乳腺增生大鼠有治疗作用,效果显著,且以中高剂量组变化最为明显。其作用机制可能通过增强机体免疫力、调节血清中E2、P水平实现。  相似文献   
143.
试验对水牛发情周期血清和唾液中雌二醇(E_2)和孕酮(P_4)的浓度变化规律、水牛唾液结晶与卵泡发育变化分别进行了分析研究,为进一步探讨水牛发情规律、指导生产提供依据。采用酶联免疫分析法(ELISA)测定发情母水牛血清和唾液中E_2和P_4的浓度变化,并对血清和唾液的激素变化规律进行相关性分析。结果表明,水牛血清和唾液中的E_2和P_4呈波动性变化。发情前期,唾液中P_4浓度一直维持在6.50~7.10 ng/mL,发情第13天达到11.09 ng/mL,随后快速下降。唾液中E_2浓度在发情第3~5天出现一个峰值178.53 pg/mL,在第14~17天唾液中E_2浓度显著升高,出现第二个峰值179.10 pg/mL。母水牛唾液中E_2和P_4浓度的变化趋势与其在血清中的变化趋势基本一致,均呈显著相关(P<0.05);唾液中E_2与P_4浓度呈极显著相关(P<0.01)。水牛发情当天唾液结晶呈现明显的蕨类作物形状且分维值显著低于其他时间点(P<0.05)。水牛发情周期唾液结晶图形的变化与卵巢卵泡发育基本同步,可作为监测水牛发情及预测排卵的可靠指标之一。  相似文献   
144.
Effect of Fasciola gigantica infection on adrenal and thyroid glands was investigated using eight male, yearling Murrah buffaloes. The animals were randomly assigned to two groups of four buffaloes each (Group-A, infected; Group-B, non-infected control). Animals of Group-A were orally infected with 1000 F. gigantica viable metacercariae, keeping other four animals of Group-B as uninfected control. In the infected buffaloes, the clinical signs began appearing from 7th week postinfection (p.i.) and eggs were detected in the faeces between day 93 and 99 (95.5+/-1.25) postinfection (p.i.). The serum cortisol level, revealed a significant (P<0.05) rise during initial stage of the infection, followed by a continuous fall from 12th week onward. Peak cortisol level on 10th week (13.30+/-2.57ngml(-1)) was associated with eosinophilia (11.0+/-0.95%). However, non-infected controls maintained almost uniform cortisol levels (3.97+/-0.15-5.88+/-0.09ngml(-1)) throughout the period of the study. The pathological changes of adrenal glands were correlated with physiological dysfunction of the glands. The levels of T(3) and T(4) were significantly (P<0.05-0.01) low from 14th week onward and were synchronous with in situ migration, growth and development of F. gigantica. Significant reduction in the thyroid hormones was further supported by histopathological evidence of lymphocytic thyroiditis confirming hypothyroidism. A decrease in Hb, PCV, total erythrocyte counts and appearance of reticulocytes in the blood of the infected buffaloes suggested regenerative anemia, which could partly be due to hypothyroidism.  相似文献   
145.
146.
The feasibility of optical coherence tomography (OCT) for imaging histological changes associated with the development of a progressive rind breakdown (RBD) disorder of ‘Nules Clementine’ mandarin (Citrus reticulate Blanco.) was investigated. The investigation utilised fruit with different levels of the disorder, carefully selected from a batch of fruit stored for eight weeks at 8 ± 0.5 °C. Images of healthy and RBD-affected intact mandarin fruit were acquired using a Thorlabs OCT system based on a broadband 930 nm source. OCT provided high resolution 2D images of fruit rind to a depth of about 1.1 mm. Immediate and non-destructive acquisition of images showing histological and microstructural features in intact rind tissues was demonstrated. The oil glands stayed intact in unaffected fruit and gradually collapsed in RBD affected fruit. At advanced stages of the disorder, the collapsed oil glands became increasingly deformed and flattened. The study showed that OCT is a promising technique for immediate, real-time and non-destructive acquisition of images showing histological and microstructural rind features of ‘Nules Clementine’ mandarin fruit.  相似文献   
147.
蜜蜂幼虫信息素对工蜂发育和采集行为的影响   总被引:1,自引:0,他引:1  
综述了蜜蜂幼虫信息素的研究现状,以及西方蜜蜂幼虫信息素对工蜂卵巢发育、工蜂王浆腺发育和工蜂采集行为发育三方面影响作用的最新研究进展.  相似文献   
148.
蚊虫在吸血过程中其唾液腺分泌一组抗凝血活性物质,这些物质不仅可干扰宿主的凝血反应和炎症反应,更是一组具有潜在药理活性的物质。本文对蚊虫抗凝血活性物质进行分类并从其特点、抗凝血作用原理、研究现状等方面进行综述,为该类物质的深入研究提供借鉴。  相似文献   
149.
为评价共免疫r FSA1和p VAX-FSA1对于猫跳蚤过敏性皮炎(FAD)的预防免疫保护效果,用人工合成的跳蚤唾液抗原(FSA1)基因,分别构建原核表达质粒p ET28a-FSA1和真核表达质粒p VAX1-FSA1。p ET28a-FSA1转化E.coli BL21(DE3)感受态细胞,诱导表达纯化FSA1,获得r FSA1。12月龄以上猫共免疫r FSA1+p VAX-FSA1,第14天实施二免后,进行跳蚤叮咬,连续4轮,跳蚤叮咬结束后,统计皮炎评分。结果显示,第4轮攻跳蚤后共免疫r FSA1+p VAX-FSA1组的猫皮炎评分远远低于FAD对照组,说明共免疫r FSA1+p VAX-FSA1能抑制FAD症状,对跳蚤叮咬猫引起的过敏性皮炎有显著保护效果,可以作为预防猫跳蚤过敏性皮炎的良好办法。  相似文献   
150.
Sixty-one medial iliac lymph nodes of 38 different dogs (eight with adenocarcinoma of the apocrine glands of the anal sac, 13 with multicentric lymphoma, six with multicentric lymphoma but in clinical remission, and 11 control dogs) were evaluated to assess the ability of ultrasound to identify and interrogate these lymph nodes across the different groups and to differentiate these groups using different sonographic parameters. Ultrasound proved to be useful to assess canine medial iliac lymph nodes. An increase in size or number of detected lymph nodes or finding rounder or heterogeneous lymph nodes could differentiate lymph nodes of dogs of the control group from lymph nodes of dogs with lymphoma or an adenocarcinoma of the apocrine glands of the anal sac. Subcategories of malignancy could not be differentiated. More studies need to be performed, both with patients with reactive lymph nodes and also focusing on other canine superficial lymph nodes, before generalizing the results of this study to other areas or diseases.  相似文献   
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