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71.
Morphological and immunohistochemical examinations were carried out on the pancreas of a hyperglycemic 5-year-old male cynomolgus monkey. Body weight gradually decreased from 6 months before termination, accompanying a slight reduction in food consumption and anorexia for the last 2 days. The blood glucose level was markedly elevated when examined at termination. Histopathologically, in the exocrine pancreas, diffuse hyperplasia of centroacinar and intercalated duct cells and diffuse atrophy of acinar cells with sporadic apoptosis were observed, although most centroacinar and intercalated duct cells were proliferating cell nuclear antigen (PCNA)-positive in both the present case and age-matched control animals. In the endocrine pancreas, the islets tended to be hypertrophic, with an increase in insulin-positive cells in comparison with the age-matched control animals. PCNA-positive cells also tended to increase in the islets, although positive cells for phospho-histone H3, a marker for mitotic cells, were not detected in the endocrine and exocrine pancreas. Moreover, neither inflammation nor amyloidosis was noted in the islets. In conclusion, the present case probably suffered from early-stage type 2 diabetes mellitus, and it provides fundamental information concerning pancreatic histopathology under insulin-related derangement in monkeys.  相似文献   
72.
棉铃虫世代种群的发展变化   总被引:3,自引:0,他引:3  
对棉铃虫种群动态的多年研究证明 ,棉铃虫年发生世代从 3.3代增加到 4.5代 ,年平均百株累计卵量增加了 4倍。主害代明显后延多发 ,完全 5代出现率已达 2 2 % ,大发生频率巨增。  相似文献   
73.
给小白鼠注射苯甲酸雌二醇诱发乳腺增生,然后用中药“乳增消”散剂外用治疗。病理学检查结果表明,苯甲酸雌二醇所致小白鼠乳腺增生类型包括小叶增生及囊性增生,中药“乳增消”外用能有效治疗乳腺增生,并对皮肤组织无毒、副作用。  相似文献   
74.
This study investigates the inhibitory effect of astaxanthin (AST) on testosterone-induced benign prostatic hyperplasia (BPH) in rats. Except for the sham operation, BPH model rats were randomly assigned to five groups: the BPH model control rats, AST-treated BPH model rats (20 mg/kg, 40 mg/kg, and 80 mg/kg), and epristeride (EPR)-treated BPH model rats. After treatment, as compared with the BPH model control rats, the prostate and ventral prostate weights of the AST-treated rats decreased, while there was a marked decline in the 80 mg/kg AST-treated rats. The same effect was also observed in the prostate index and ventral prostate index. The proliferation characteristics of epithelia observed in the BPH model control group were gradually alleviated in the AST-treated rats. As compared with the BPH model control rats, lower epithelial thicknesses of prostates and fewer secretory granules in epithelia were observed in the AST-treated rats. The superoxide dismutase (SOD) activity of prostates increased in all the AST-treated rats with a significant increase in the 40 mg/kg and 80 mg/kg AST-treated rats. The testosterone (T) and dihydrotestosterone (DHT) levels of prostates in the AST-treated groups were lower than those in the BPH model control group, and a significant decline was found in the T level of prostates in the 40 g/kg and 80 mg/kg AST-treated rats and the DHT level of prostates in the 40 mg/kg AST-treated rats. These results indicate that AST might have an inhibitory effect on T-induced BPH in rats, possibly due to SOD activity regulation and T and DHT levels.  相似文献   
75.
This study has investigated the muscle growth of diploid and triploid Atlantic cod (Gadus morhua) juveniles raised in replicate tanks over a period of 29 weeks and analysed at three sampling points (February, June and September). Data for weight, length, condition factor (K), muscle fibre growth and myogenic progenitor cells (MPCs) number were collected and results were analysed in relation to body growth and ploidy status. Diploids were significantly heavier than triploids throughout the trial (~10–20%) and had K in June and September samplings. Over the whole period, the rate of muscle fibres' recruitment was 318 fibres per day and 252 fibres per day for diploid and triploid cod respectively. The larger body weight of diploids resulted in a total number of fast fibre number of 114 979 compared to 91 086 in triploids. The average diameter of the 2.5% of the smallest fibres (2.5th percentile) was higher in diploids than triploids at the start of the trial, with a reversed picture for the average of the upper 2.5% (97.5th percentile) at the end of the trial. The probability density function of the estimated muscle fibre diameters showed similar fibre size distribution between size‐matched diploids and triploids at all sample points. The peak fibre diameter was approximately 25 μm in February and increased to approximately 50 μm in June and September, irrespectively of ploidy. Pax 7 were used as molecular markers for MPCs. A positive correlation between Pax 7+ cells and total body length was observed only among triploid fish at the onset of the experiment.  相似文献   
76.
Background: Recognition of different cytologic patterns in lymph nodes (LNs) from dogs with canine monocytic ehrlichiosis (CME) and noninfectious causes of lymphoid reactivity may have diagnostic utility. Objectives: The aims of the present study were to compare cytologic patterns in LNs of dogs with different phases of CME, to investigate the association of cytologic pattern and presence of Ehrlichia spp. morulae, and to compare patterns of lymphoid reactivity between dogs with CME and those with noninfectious causes of lymphoid hyperplasia. Methods: Cytologic preparations of LNs from 35 dogs with nonmyelosuppressive CME (group A), 16 dogs with myelosuppressive CME (group B), 26 dogs with noninfectious diseases (group C), and 15 healthy dogs (group D) were evaluated. Percentages of lymphocyte types, plasma cells, macrophages, neutrophils, and eosinophils were determined. Samples from dogs in groups A and B were evaluated for the presence of morulae. Results: Cytologic abnormalities in LNs were recorded in 54% of dogs in group A, 88% in group B, 39% in group C, and 0% in group D and were more frequent (P=.02) in dogs with myelosuppressive CME than those with nonmyelosuppressive CME. Plasma cell hyperplasia was more frequent in CME than in noninfectious diseases (P=.03). An association between the presence of cytologic abnormalities and morulae in group A dogs was not found. Conclusions: Dogs with myelosuppressive CME have more lymphoid cytologic abnormalities than dogs with nonmyelosuppressive CME. LN plasmacytosis is the major pattern of lymphadenopathy in dogs with CME and is found more frequently in dogs with CME than in dogs with noninfectious causes of lymphadenopathy.  相似文献   
77.
The purpose of our study was to create a novel rat aorta stent implantation model. Stainless steel bare metal stents (BMS) or paclitaxel-eluting stents (PES) were implanted in male Sprague-Dawley rats (BW 400 ± 20 g). Two and four weeks after stent implantation, the aorta were collected, fixed with 2% glutaraldehyde, and cut into two segments. One segment was used for scanning electron microscopy analysis to evaluate re-endothelialization, and the other segment was used to calculate the neointimal area. At 2 weeks after stenting, the appearance of neointimal hyperplasia was less in the PES group than in the BMS group. At 4 weeks after stenting, no significant difference in neointimal hyperplasia was observed between two groups. On the other hand, the PES group showed more thrombus formation and less re-endothelialization compared to the BMS group. This study demonstrated the ability of a novel rat model of aorta stenting via a common carotid artery to measure the efficacy and safety of commercially available drug-eluting stents.  相似文献   
78.
Congenital hypothyroidism and dysmaturity syndrome (CHD) in neonatal foals was first described in western Canada in 1981 and remains an important problem for the western Canadian horse industry. This syndrome is characterised by hyperplasia of the thyroid gland, increased gestational length and multiple congenital musculoskeletal abnormalities. This case series describes the first confirmed cases of CHD in Europe and challenges contemporary opinion which suggests that this syndrome is distinct from congenital hypothyroidism associated with visible goitre.  相似文献   
79.
It is extremely rare to have multiple spontaneous proliferative lesions in young adult rats. Here, we report the occurrence of different proliferative lesions in multiple tissues of a 7-week-old female rat in a 1-week repeated toxicity study. Grossly, multiple white patches and nodules in the bilateral kidneys, femoral and subcutaneous masses, and a nodule in the liver were observed. Renal lesions were diagnosed as renal mesenchymal tumors. One of the femoral subcutaneous masses was diagnosed as an adenolipoma consisting of mammary epithelial cells and mature adipocytes. The other femoral and abdominal subcutaneous masses were diagnosed as lipomas consisting of mature adipocytes. The liver nodule was diagnosed as non-regenerative hepatocellular hyperplasia, which was characterized by the proliferation of slightly hypertrophic hepatocytes. In the cauda equina, the growth of enlarged Schwann cells around the axon was observed, and this lesion was diagnosed as a neuroma.  相似文献   
80.
Saline groundwater is being pumped from a number of locations in rural Western Australia to prevent secondary salinity impacting farmland, rural infrastructure and areas with high conservation value. Aquaculture may offset the costs of groundwater pumping, and the suitability of groundwater for finfish aquaculture is being assessed through bioassays. There are marked spatial variations in the ionic composition of saline ground water in Western Australia and this paper describes two bioassays investigating a saline, potassium-deficient water source that resulted in mortalities in juvenile barramundi, Lates calcarifer (Bloch). Histopathological examination revealed severe degeneration and necrosis of skeletal muscles, marked hyperplasia of branchial chloride cells and renal tubular necrosis. Clinical chemistry findings included hypernatraemia and hyperchloridaemia of the blood plasma and lowered muscle potassium levels. It is concluded that the principal cause of death was skeletal myopathy induced by low water potassium levels.  相似文献   
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