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71.
河南大别山区野生草本花卉资源与合理利用   总被引:9,自引:2,他引:9  
在调查研究的基础上,介绍了河南大别山区的植物资源,列举了27个科有较大观赏价值的野生草本花卉100种,并对其开发、利用、保护及引种驯化提出了建议。  相似文献   
72.
AIM: To determine the weight, volume, density and cross-sectional area (CSA) of the digital flexor tendons, common digital extensor tendon (CDET) and suspensory ligament (SL) of the forelimb of young Thoroughbred horses in early training, and to assess the response to a training programme of known parameters of superficial digital flexor tendon (SDFT) tissue at mid-metacarpal level.

METHODS: The tendons of seven 2-year-old Thoroughbred horses in training were inspected, transected into segments of known length, and compared with those from seven untrained horses matched for age, sex and breed. The weight, volume, density and CSA of each segment, and the crimp angle, histological features, and biomechanical ultimate stress and stiffness of tendon samples from the mid-metacarpal region of the SDFT were determined.

RESULTS: There was no macroscopic evidence of swelling or discolouration in any of the tendon segments or cut surfaces. The volumes of SDFT and CDET segments of horses in the trained group were significantly greater than those in the untrained group (p=0.036 and p=0.039, respectively). A greater increase in volume than weight resulted in a lower density in the SDFT but not CDET in trained compared with untrained horses (p=0.038). CSA of these two tendons was significantly greater in the trained group (p=0.002 and 0.036, respectively), the percentage increase being greater in the CDET than the SDFT. The number of tenocytes at four sites in the mid-metacarpal SDFT region was less in trained than untrained horses (p=0.025). There was no histological evidence of inflammation, and no difference in crimp angle between groups. There was no significant between-group difference in stiffness or ultimate stress of tendon strips.

CONCLUSIONS: Volume and CSA of the SDFT and CDET were larger in trained than untrained horses. The SDFT was less dense in the trained group. Because no evidence of tendonitis was detected and training appeared to have no significant effect on crimp angle or biomechanical properties of tendon strips, the size and density changes were presumed to be adaptive and induced by the training.

CLINICAL RELEVANCE: Although evident in this in vitro study, the detection of adaptive from initial pathological increase in size of the SDFT is likely to be difficult in vivo.  相似文献   
73.
Variation in the immune status of two Australian pig breeds   总被引:1,自引:0,他引:1  
Objective To investigate the variation in immune competence of two Australian pig breeds.
Design A panel of immune tests were used to assess breed and sire differences in weaner piglets of Large White and Duroc breeds.
Procedure All piglets were immunised against porcine leptospirosis. Blood samples were taken for studies on lymphocyte phenotypes, mitogenic responses of blood cells and serological analysis.
Results Significantly larger blood leucocyte numbers were found in Large White piglets compared with Duroc piglets after vaccinations. No significant difference in concanavalin A induced blood cell proliferation was found between these two breeds before or after vaccinations. Some significant breed variation in blood lymphocyte phenotypes was found. While the age-related changes of lymphocyte phenotypes were similar for the two breeds, the Large White breed had significantly larger numbers of CD2+ and CD4+ cells than the Duroc breed after the two vaccinations. There were also significant sire effects on CD8+ cells within the Large White breed after the first vaccination. No significant breed difference was detectable in serum IgG concentrations but sire differences within each breed before the primary vaccination were found. The serum antibody response to vaccination against leptospirosis was generally small, and showed no variations due to either breed or sire. No gender effects were found during the entire study.
Conclusion The study demonstrated significant differences in some important immune components of the pig breeds studied. This may in turn indicate the variation in their immune competence or disease resistance. However, further investigation into the heritability and correlation with specific immune responses is required.  相似文献   
74.
A craniomedial approach to the scapulohumeral joint of the dog is described for the removal of large, intraarticular cartilaginous bodies from the medial aspect of the joint. This technique was used successfully in 4 dogs with chronic osteochondritis dissecans in which the medial aspect of the joint was inaccessible through a standard lateral approach.  相似文献   
75.
The clinical manifestations of equine pituitary pars intermedia dysfunction (PPID) in temperate climates are well described. The classic presentation is that of an older animal with hirsutism, laminitis, poor muscle tone, pendulous abdomen and weight loss. This case series highlights the additional clinical signs of anhidrosis and heat stress with secondary exercise intolerance that were seen as primary presenting problems in equids with PPID in the hot, humid conditions of a tropical climate. The clinical signs resolved with medical treatment for PPID.  相似文献   
76.
In the late summer and autumn of 1980 kikuyu poisoning of cattle was diagnosed on 9 farms in New South Wales resulting in 213 deaths among 1370 cattle at risk. Clinical, autopsy and histopathological findings are described and are consistent with those previously recorded. Kikuyu grass samples from 5 paddocks in which deaths were occurring were examined for the presence of fungi. Myrothecium spp were not present. Fusarium semitectum, F. moniliforme var subglutinans, Penicillium spp and a Phoma sp were the most common fungi isolated but with the exception of F. semitectum were not consistently present. F. semitectum was present in adjacent kikuyu grass paddocks in which deaths were not occurring. Two of the farms had army caterpillar (Mythimna convecta) infestations. Army caterpillar faeces present in these paddocks did not contain Myrothecium spp; the fungi present reflected the population present on the kikuyu grass. These findings do not suggest a mycotic cause for kikuyu poisoning.  相似文献   
77.
Abstract

AIM: To assess the stability of creatine kinase (CK) activity in plasma collected from healthy foals and frozen at ?20°C for up to 12 weeks.

METHODS: Samples of venous blood drawn from 25 foals were analysed for CK activity soon after collection, and again after 1 and 12 weeks of freezing at ?20°C.

RESULTS: CK activity decreased (p<0.001) between Week 0 and Week 1 and between Week 0 and Week 12.

CONCLUSIONS AND CLINICAL RELEVANCE: Decreases in CK activity were statistically significant but clinically insignificant.  相似文献   
78.
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80.
The study was conducted to evaluate effect of ratio of face to core particles on mechanical and physical properties of oriented strand board produced from Ethiopian highland bamboo.Three-layered oriented particleboards were manufactured with 4 proportions of face to core particles at 750 kg/m~3 target density.Ten percent urea formaldehyde resin was used as a binder.Strength and dimensional stability performances of all boards were assessed based on ISO standards.The results showed that modulus of rupture...  相似文献   
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