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91.
克氏原螯虾原肌球蛋白的纯化及过敏原性分析   总被引:1,自引:0,他引:1  
以13份甲壳类动物过敏患者血清的Western—blotting分析,确定克氏原螯虾主要过敏原为36ku蛋白质.通过盐析、等电点沉淀及热处理等方法纯化该蛋白质,以兔抗拟穴青蟹原肌球蛋白(Tropo-myosin,TM)多克隆抗体的Western—blotting分析,确定该蛋白质为TM.同源性分析表明,克氏原螯虾TM与南美白对虾TM、拟穴青蟹的氨基酸序列相似性较高(〉90%).酶切位点预测显示,它分别有49个胰蛋白酶和6个胰凝乳蛋白酶的酶切位点.模拟胃肠液消化实验结果显示,纯化TM不易被胃蛋白酶降解,易于被胰蛋白酶和胰凝乳蛋白酶降解,进一步的Western—blotting和抑制性ELISA分析结果显示,其消化产物仍具有一定的免疫活性.采用蒸煮处理可降低TM的消化稳定性及免疫活性,且蒸煮处理时间越长,效果越显著.说明。TM为克氏原螯虾主要过敏原.与其他甲壳娄动物TM的序列相似件较高.  相似文献   
92.
A 12-year-old American Saddlebred gelding was referred to a veterinary teaching hospital for evaluation of a chronic lameness problem in the right radiocarpal joint. The horse had been treated for osteoarthritis of the right radiocarpal joint with multiple injections of cortisone during the past 3 years. The horse was severely lame on the right forelimb at a trot. Radiography and computed tomography revealed a 3 x 2-cm lytic defect in the distal portion of the radius and periarticular bone proliferation around the right radiocarpal joint. Ultrasonography of the distal portion of the radius revealed a soft tissue mass in the palmarolateral aspect of the joint. Proliferative synovium with a large amount of fibrin was observed in the dorsal and palmar aspects of the joint via arthroscopic examination of the right radiocarpal joint. Histologic examination of synovial biopsy specimens revealed proliferative granulomatous synovitis with giant cells. Mycobacterium avium complex was cultured from the synovial fluid. Infection with M avium complex should be considered in horses with chronic recurring arthritis associated with granulomatous synovitis.  相似文献   
93.
The purpose of this study was to evaluate the effect of cooling ovarian tissue on pig pre-antral follicles. Ovaries were maintained in saline solution (0.9%) at 4 or 20 degrees C for 6, 12 or 18 h. After storage, pre-antral follicles were morphologically evaluated. While primordial follicles were not affected by the storage, the percentage of morphologically normal growing follicles was significantly reduced in ovarian tissue stored at 20 degrees C for 12 or 18 h. To test the viability of stored follicles, growing follicles isolated from ovaries stored at 4 degrees C for 18 h and at 20 degrees C for 6 h were cultured for 3 days. Follicles stored in either condition presented the same growth pattern in vitro as fresh follicles. We conclude that storage of pig ovaries at 4 degrees C for up to 18 h or at 20 degrees C for up to 6 h does not affect the morphology of growing follicles or their ability to grow in vitro.  相似文献   
94.
95.
OBJECTIVE: To compare monotonic mechanical properties of gap-ostectomized third metacarpal bones (MC3) stabilized with an MP35N interlocking nail system with contralateral intact bones. ANIMALS OR SAMPLE POPULATION: Twenty-four pairs of cadaveric equine MC3s. METHODS: Third metacarpal bones were divided into 4 mechanical testing groups (6 pairs per group): compression, palmarodorsal (PD) and mediolateral (ML) 4-point bending, and torsion. One MC3 from each pair was randomly selected as an intact specimen, and the contralateral gap ostectomized bone was stabilized with a 4-hole, 14-mm-diameter, 250-mm-long, MP35N intramedullary nail, and four, 7-mm-diameter, 60-mm-long MP35N interlocking screws (constructs). Mechanical testing properties were compared between intact specimens and constructs with a paired t test (significance set at P <.05). RESULTS: Intact specimens were significantly stronger and stiffer than constructs in all testing modes except PD bending. Constructs achieved mean yield strengths that were 57% (compression), 81% (PD bending), 68% (ML bending), and 78% (torque) of intact specimens. Constructs achieved mean stiffnesses that were 53% (compression), 58% (PD bending), 41% (ML bending), and 47% (torque) of intact specimens. CONCLUSION: Monotonic yield mechanical properties of MP35N intramedullary interlocking nail-stabilized, gap-ostectomized MC3 were lower than those of paired intact bones but exceeded reported in vivo loads for dorsopalmar bending and compression and estimated in vivo torsional loads. CLINICAL RELEVANCE: Considering the benefits associated with intramedullary interlocking nail fixation of fractures, this system should be considered for use for repair of MC3 fractures with applicable fracture configurations.  相似文献   
96.
SUMMARY Many of the nervous and muscular locomotor disorders that affect sheep throughout Australia are commonly referred to as ‘staggers’ syndromes. The range of clinical signs displayed by sheep suffering these disorders is sufficiently diverse to enable each syndrome to be graded into one of 5 progressive clinical groups. The first group, the limb paresis syndromes, includes the primary myopathies associated with the ingestion of Ixiolaena brevicompta, Malva parviflora, and Trachymene ochracea, as well as selenium and vitamin E disorders, Paroo virus staggers, congenital progressive muscular dystrophy, humpy back, hypocalcaemic muscle weakness, Tribulus terrestris staggers and tetanus . The second group is characterised by limb paresis with knuckling of the fetlocks, and includes the plant-associated toxicities of Romulea rosea, Stachys arvensis, Trachyandra divaricata, and Tribulus micrococcus, together with haloxon toxicity, enzootic ataxia (copper deficiency), and the probably genetic disorders of segmental axonopathy, neuroaxonal dystrophy, and degenerative thoracic myelopathy. Other locomotor disorders that fit more loosely into this group are listerial myelitis (post-dipping staggers), vitamin A deficiency, cervico-thoracic vertebral subluxation, Stypandra glauca toxicity, Ipomoea spp toxicity, ivermectin toxicity, and botulism . The third group, the falling syndromes, includes the probably genetic disorders of thalamic cerebellar neuropathy, cerebellar abiotrophy, and globoid cell leucodystrophy, together with Swainsona spp toxicity . The fourth group, the falling-with-tremors syndromes, includes the plant-associated toxicities of phalaris staggers, perennial rye grass staggers and nervous ergotism (Claviceps paspali) . The fifth group, the convulsive syndromes, includes the polioencephalomalacic entity nardoo fern (Marsilea drummondii) staggers, outbreaks of focal symmetrical encephalomalacia and the tunicaminyluracil toxicities known as annual ryegrass (Lolium rigidum) toxicity, annual beard grass (Polypogon monspeliensis) toxicity, blow away grass (Agrostis avenaceae) toxicity, and water damaged wheat (Triticum aestivum) toxicity . A dichotomous system is presented for the differential diagnosis of these groups of conditions .  相似文献   
97.
The aim of the present paper is to make a comparative study of the expression of the elements of the insulin‐like growth factor (IGF) system in different mammalian species and thus illuminate their potential role in the process of ovarian folliculogenesis in mammals. In most mammalian species, IGFs and IGFBPs (in particular IGFBP‐2 and IGFBP‐4) are considered, respectively, as stimulators and inhibitors of follicular growth and maturation. In mammalian species, IGFs might play a key role in sensitizing ovarian granulosa cells to FSH action during terminal follicular growth. Concentrations of IGFBP‐2 and IGFBP‐4 in follicular fluid strongly decrease and increase during follicular growth and atresia, respectively, leading to an increase and a decrease in IGF bioavailability, respectively. The decrease in these IGFBPs is because of a decrease in mRNA expression (IGFBP‐2) and an increase in proteolytic degradation by PAPP‐A in follicular fluid (IGFBP‐2, IGFBP‐4 and IGFBP‐5), and likely participates in the selection of dominant follicles. In contrast, levels and/or sites of expression of IGF‐I, IGF‐II, IGFBP‐4, IGFBP‐5 and type II receptor in follicular cells strongly differ between mammalian species, suggesting that these phenomena might play species‐specific or secondary roles in ovarian folliculogenesis.  相似文献   
98.
The clinical signs displayed by 96 sheep affected by the nervous syndrome of Phalaris aquatica toxicity and 10 normal sheep injected intravenously with the phalaris alkaloid, 5-methoxy dimethyltryptamine (dose range 0.01 to 5.0 mg/kg), were observed. The distributions of phalaris indole-like cytoplasmic pigments in nuclei of the brains and spinal cords of 9 naturally affected sheep were determined microscopically. Based on the relationship between clinical signs and the central nervous system nuclei involved in their production, the distribution of phalaris indole-like pigments, and the pharmacology of dimethylated tryptamines, it is suggested that the nervous syndrome induced by Phalaris aquatica results from a direct action of phalaris alkaloids upon serotonergic receptors in specific brain and spinal cord nuclei.  相似文献   
99.
The objective of this study was to determine the activity of steroid‐ and eicosanoid‐metabolizing enzymes in horses with varying BCSs. The BCSs of twenty non‐pregnant, anoestrous mares were determined prior to euthanasia, and tissue samples were collected from the liver, kidney, adrenal gland, ovary and endometrium. Cytochrome P450 1A (CYP1A), 2C (CYP2C), 3A (CYP3A) and uridine 5′‐diphospho‐glucuronosyltransferase (UGT) activities were determined using luminogenic substrates. The MIXED procedure of SAS was used to test the effect of BCS on enzyme activity and differences between tissues. Activity of CYP1A in adrenals was increased ( .05) in BCS 5 versus BCSs 4 and 6. Activity of CYP1A in the liver was increased (= .05) in BCS 4 versus BCSs 5 and 6. Activity of CYP1A was 100‐fold greater (< .0001) in the liver than in the adrenal, ovary and kidney. Activity of CYP2C was 100‐fold greater (< .0001) in the liver than in the adrenal, ovary and endometrium. Activity of CYP3A was only detectable in the liver. Activity of UGT in the kidney was decreased (= .02) in BCS 4 versus BCSs 5 and 6. Activity of UGT was threefold greater (< .0001) in the liver than in the kidney, whereas activity of UGT was ninefold greater (< .0001) in the kidney than in the ovary and endometrium. In general, BCS did not alter the activity of steroid‐ and eicosanoid‐metabolizing enzymes in horses. However, tissue differences in these enzymes indicated abundant hepatic metabolism in horses, which is similar to other livestock species.  相似文献   
100.
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