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21.
实验性附睾淤积症引起家犬附睾起始部主细胞超微结构异常改变,但较附睾体部所见为轻;经超声波处理后(功率0.75W/cm~2,每日一次,每次8min,连续7日)则见其明显改变、或完全恢复,且未造成附睾起始部主细胞新的损伤。本实验结果在与附睾体部主细胞相应变化进行比较后,发现由于附睾淤积症对附睾管不同部位的影响是不同的,因而这种形态和功能均已不同程度改变了的附睾不同部位的主细胞对超声波作用的反应也各不相同,这除因主细胞功能状态不同外,尚与超声波声场的不均匀有关,提示探寻超声波治疗最适宜的量不仅必要,而且是有可能找到的。 相似文献
22.
鼠骨关节炎动物模型建立的现状 总被引:12,自引:2,他引:10
骨关节炎(osteoarthritis,OA)是临床上常见的疾病。探索骨关节炎动物模型的建立方法,是研究其病因和治疗方法的重要课题之一。鼠是一种理想的动物,所用的方法有关节内手术、关节内注射、关节外手术等,各种方法都有自己的长处和不足。本文就鼠骨关节炎动物模型的建立方法、模型特点及其应用等方面进行综述。 相似文献
23.
广州家禽、家畜批发市场六种动物隐孢子虫感染情况的调查 总被引:4,自引:1,他引:3
目的调查广州家禽、家畜批发市场兔、鸭(含雏鸭)、羊、鸡、狗、鸽6种动物的隐孢子虫感染情况。方法取上述动物的粪便292份,用金胺-酚-改良抗酸复染法染色,镜检卵囊。结果检查的6种动物均发现有隐孢子虫感染,自然感染率分别为:64.1%,54.3%(45.0%),21.7%,20.6%,20.0%,14.6%。结论广州家禽、家畜批发市场6种动物存在隐孢子虫感染。 相似文献
24.
Illana Gozes John Glowa Douglas E. Brenneman Susan K. McCune Eric Lee Heiner Westphal 《Journal of molecular neuroscience : MN》1993,4(3):185-193
The molecular mechanisms responsible for behavior are largely unknown. A state of the art model, paving the path from genes
to behavior, is offered by transgenic animals. Candidate molecules are classic neuropeptides, such as vasoactive intestinal
peptide (VIP). Transgenic mice harboring a chimeric VIP gene driven by the polyoma promoter were produced. Behavioral studies
revealed learning impairment and prolonged retardation in memory acquisition in the genetically altered animals. Furthermore,
reduced performance was observed when the male transgenic mice were tested for sexual activity in the presence of receptive
females. Surprisingly, radioimmunoassays showed an approx 20% decrease in the VIP content of the transgenic mice brains. To
directly assess genetically reduced VIP content as a cause for learning impairment, transgenic mice carrying diphtheria toxia-encoding
sequences driven by the rat VIP promoter were created. These animals had reduced brain VIP and exhibited deficiencies in learning
abilities, strongly supporting an important neurobiological function for VIP in vivo. 相似文献
25.
During the evolution of teeth, different types of periodontal attachment have been developed. On the basis of the comparative histology of periodontal tissues, protoacrodontal, acrodontal, acro-protothecodontal, pleurodontal and thecodontal structures can be distinguished that depend upon the area of attachment (crestal, marginal or socketed type) and the mode of attachment (ankylosis, fibrous or combined type). Due to "phylogenetic memory", changes of the periodontium in health and disease could be interpreted as copies of phylogenetically older patterns. The greatest variations in tooth attachment have originated in acrodont bony fishes and in pleurodont reptiles, whereas the selection for a single thecodont or socketed type was an important event in the evolution of mammals. The detailed structures of cementum, of the fiber apparatus and of the junctional epithelium vary from type to type and within one type. These principal structures are decisive for reaction patterns of degeneration and regeneration. Therefore, comparative periodontology could be an important adjunct to help interpret the natural history of periodontal diseases, to help in the selection of experimental animals and to help provide treatment strategies in both human and veterinary situations. 相似文献
26.
The present study was a longitudinal study of age-related changes in performance of the 5-choice serial reaction time task, a test of visual attention. Following acquisition of the task, animals were tested on two occasions on their ability to perform the 5-choice task. In Test 1 (Young: 7 months; Aged: 13–14 months) no age-related effects on baseline performance were revealed. However, increasing the attentional load of the task revealed an impairment in choice accuracy by animals of the Aged group. In Test 2 (Young: 10–11 months; Aged 23–24 months), animals of the Aged group were significantly impaired on the baseline schedule of the task compared to the Young group. The deficit in accuracy on the task could be improved in the Aged animals by decreasing the attentional load. The results of the present study suggest a deficit in attentional function as a result of the aging process, markedly similar to that observed following lesions of the basalo-cortical cholinergic system. 相似文献
27.
In order to determine the allergenic activity of five purified horse allergens, 22 children allergic to horses according to history, skin test, and leukocyte histamine release were evaluated. Washed leukocytes from all patients were tested for allergen-induced histamine release utilizing four epidermal horse allergens (Ags 6, 9, 11 , and 15) and horse serum albumin. Crossed radioimmunoelectrophoresis was carried out with a standardized horse dander extract and serum from each patient.
The results showed considerable variation in the individual allergoprints. Ag 11 had the highest mean allergenic activity. Sensitivity to horse serum albumin was demonstrated three times. Our data show that the amount of serum IgE antibodies bound by horse allergens correlates significantly with the capacity of the allergens to induce histamine release from washed leukocytes. 相似文献
The results showed considerable variation in the individual allergoprints. Ag 11 had the highest mean allergenic activity. Sensitivity to horse serum albumin was demonstrated three times. Our data show that the amount of serum IgE antibodies bound by horse allergens correlates significantly with the capacity of the allergens to induce histamine release from washed leukocytes. 相似文献
28.
邦得林治疗雄性骨质疏松大鼠的实验研究 总被引:5,自引:2,他引:3
目的:探讨邦得林(羟乙膦酸钠)对男性骨质疏松内代的影响。方法:采用15周龄雄性大鼠去睾后作为动物模型,随机分为3组:正常对照组、去势组、邦得淋治疗组,28周后行血尿生化、骨密度、骨生物力学及病理检查。结果:与正常组比较,模型组睾酮水平明显下降(P<0.01),全身及股骨中点骨密度明显下降(P<0.05),碱性磷酸酶显著降低(P<0.01),24h尿羟脯氨酸、尿钙与肌苷比显著增高(P<0.05),股骨最大受力负荷及股骨最大挠度均显著下降(P<0.05),骨小梁体积、骨表面面积/体积、平均骨小梁厚度显著下降(P<0.01);邦得林治疗组大鼠全身与股骨骨密度显著下降(P<0.05),弹性模量显著增加(P<0.05),24h尿羟脯氨酸、尿钙与肌苷比值已降低到正常组大鼠水平,骨小梁体积、平均骨小梁厚度、平均骨小梁板间隙明显上升(P<0.01),平均骨小梁板密度明显下降(P<0.01)。结论:去势使大鼠骨形成减慢,骨吸收加速,造成了男性骨质疏松的动物模型。早期应用邦得林可缓解雄激素缺乏引起的骨吸收加速,但仍不能完全预防骨质疏松的发生。 相似文献
29.
Apolipoprotein genes and atherosclerosis 总被引:1,自引:0,他引:1
J. L. Breslow 《Journal of molecular medicine (Berlin, Germany)》1992,70(5):377-384
Summary In order to elucidate the genetic abnormalities underlying lipoprotein disorders associated with coronary heart disease susceptibility, researchers have looked for candidate genes. The studies have focused particularly on the lipoprotein transport genes. Relatively common as well as rare mutations have already been identified in several of these genes. In addition, further metabolic and genetic studies indicate that some of these loci harbor significant, but as yet undefined, genetic variation. In the next few years, it is not unreasonable to expect that all or most of the significant mutations at these loci will be catalogued. It is too early to know whether this will be sufficient to explain the genetic basis of altered lipoprotein levels or whether new loci will need to be investigated. Additional candidate gene loci might be those coding for genes involved in intracellular cholesterol metabolism, cholesterol absorption, or insulin resistance. New loci may also be revealed by the technique of reverse genetics. A more complete understanding of the genetics of atherosclerosis susceptibility will probably also entail the identification of variants at genetic loci that control both the reaction of the blood vessel wall to atherogenic lipoproteins and the thrombosis system. Investigation of the genetic basis of coronary heart disease susceptibility remains a worthwhile and lively field, with important clinical and public health ramifications.Abbreviations LPL
lipoprotein lipase
- HL
hepatic lipase
- LCAT
ecithin cholesteryl acyltransferase
- CETP
cholesteryl ester transfer protein
- RFLP
restriction fragment length polymorphism
- FCR
fractional catabolic rate
- HDL, LDL, VLDL, SDL
high, low, very low, intermediate density lipoproteins 相似文献
30.
The ontogeny of lymphocytes expressing J chain in the cytoplasm (J+) was studied in pig foetuses by the immunofluorescent technique. Peripheral blood lymphocytes were the first J+ cells in prenatal life. The spleen and lymph nodes contained J+ cells in the last days of gestation. J+ cells were found in the lamina propria of the gut and some glands of conventional but not of germ-free piglets. J chain was not detected on or in cell membranes at any developmental stage. 相似文献