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排序方式: 共有345条查询结果,搜索用时 140 毫秒
121.
STEVEN F. SWAIM DVM MS ALICE H. LEE DVM JOHN A. McGUIRE PhD 《Veterinary surgery : VS》1984,13(1):18-25
The development of dog-ears of redundant skin or removal of large areas of additional skin are problems often encountered when closing circular skin defects. Defects 3 cm in diameter were created along the backs of dogs. Eight techniques of reconstruction were evaluated by measuring the area of additional skin removed and length of final suture line and by counting the number of dog-ears produced. The eight techniques were linear, fusiform, double S, three point, four point, pin wheel, bow tie, and combined V closures. Based on the results of this study, the linear, combined V, and bow tie techniques provide the best closure. In general, the linear technique should be used when skin edges can be apposed without the formation of dog-ears (e.g., smaller defects). When skin edge apposition results in dog-ear formation and when there is limited skin for reconstruction surrounding the defect, the combined V technique should be used. When larger dog-ears form as the skin edges are apposed and when there is an abundance of skin surrounding the defect, the bow tie technique could be considered for closure. One-half of the bow tie technique can be used to approximate wound edges where one edge is long and curved. 相似文献
122.
A model is described for predicting the dynamic changes in theproportion of tree, shrub and grass life forms at the globalscale. This model is driven by the impacts of climate, soilsand CO2 on global vegetation leaf area index and net primaryproductivity. The life-form model has been used to explore theinfluences of global warming and continued CO2 increase on treecover This reflects a realization from other modelling workthat forested vegetation, at the global scale, exerts significantinfluences on climate, and so it is important to assess thepotential for this feedback under climatic change. An increase in CO2 from 350 to 560 p.p.m. is modelled to haveonly a small impact on tree cover, under current climate. Aregionally-consistent and global increase in temperature ofc.2{ring}C and a 10 per cent increase in precipitation, butwith no increase in CO2, indicates a significant potential fortrees to spread into current shrub tundra, over a period of50 years This could lead to regional warming, through changesin winter albedo. The effect of the CO2 increase is most noticeablein interaction with increases in temperature (2{ring}C) andprecipitation (10 per cent). In this case the life-form modelprojects further increases in tree cover, particularly in areaswith seasonally low periods of precipitation. 相似文献
123.
Abstract. enhancement of plaque formation by IHN virus on CHSE-214 cells was obtained with 2–5 /(μ/ml polybrene. The enhancement is due to increased infectivity of small plaque variants in the IHN virus stock. 相似文献
124.
Six adult dogs were presented with an unusual bullous dermatosis affecting the glabrous skin of the ventral abdomen and medial thighs. Clinically, flaccid bullae were accompanied by erythema, ulceration, haemorrhage and hyperpigmentation in four of six dogs; the remaining two dogs had thin skin without grossly apparent bullae. Histologically, subepidermal bullae and clefting, vascular proliferation and dilatation (phlebectasia), and alteration in the density and staining of superficial dermal collagen were seen in all dogs. In all cases, corticosteroid-containing topical products had been applied to the affected areas prior to the development of the dermatosis; skin lesions resolved when topical corticosteroids were withdrawn. Follow-up biopsy of three dogs showed resolution of the previously abnormal collagen and subepidermal clefting. Residual lesions included phlebectasia, comedones and hyperpigmentation. The authors postulate that subepidermal clefting was due to local, corticosteroid-induced skin fragility. This is the first report, to our knowledge, of bullous skin disease in dogs resulting from topical corticosteroid therapy. 相似文献
125.
Manabu TANABE Hiroshi TAMURA Toshiaki TAKETANI Maki OKADA Lifa LEE Isao TAMURA Ryo MAEKAWA Hiromi ASADA Yoshiaki YAMAGATA Norihiro SUGINO 《The Journal of reproduction and development》2015,61(1):35-41
Melatonin protects luteinized granulosa cells (GCs) from oxidative stress in the follicle during ovulation. However, it is unclear in which cellular components (e.g., nuclei, mitochondria, or plasma membranes) melatonin works as an antioxidant. GCs from immature (3 wks) ICR mice were incubated with hydrogen peroxide (H2O2; 0.01, 0.1, 1, 10 mM) in the presence or absence of melatonin (100 μg/ml) for 2 h. DNA damage was assessed by fluorescence-based immunocytochemistry using specific antibodies for 8-hydroxydeoxyguanosine (8-OHdG), an indicator of oxidative guanine base damage in DNA, and for histone H2AX phosphorylation (γH2AX), a marker of double-strand breaks of DNA. Mitochondrial function was assessed by the fluorescence intensity of MitoTracker Red probes, which diffuse across the membrane and accumulate in mitochondria with active membrane potentials. Lipid peroxidation of plasma membranes was analyzed by measuring hexanoyl-lysine (HEL), a oxidative stress marker
for lipid peroxidation. Apoptosis of GCs was assessed by nuclear fragmentation using DAPI staining, and apoptotic activities were evaluated by caspase-3/7 activities. H2O2 treatment significantly increased the fluorescence intensities of 8-OHdG and γH2AX, reduced the intensity of MitoTracker Red in the mitochondria, increased HEL concentrations in GCs, and enhanced the number of apoptotic cells and caspase-3/7 activities. All these changes were significantly decreased by melatonin treatment. Melatonin reduced oxidative stress-induced DNA damage, mitochondrial dysfunction, lipid peroxidation, and apoptosis in GCs, suggesting that melatonin protects GCs by reducing oxidative stress of cellular components including nuclei, mitochondria, and plasma membranes. Melatonin helps to maintain the integrity of GCs as an antioxidant in the preovulatory follicle. 相似文献
126.
Jin HUR Seong Kug EO Sang-Youel PARK Yoonyoung CHOI John Hwa LEE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(12):1693-1696
Salmonella Typhimurium strain expressing the Actinobacillus
pleuropneumoniae antigens, ApxIA, ApxIIA, ApxIIIA and OmpA, was previously
constructed as a vaccine candidate for porcine pleuropneumonia. This strain was a live
attenuated (∆lon∆cpxR∆asd)Salmonella as a delivery host
and contained a vector containing asd. An immunological study of
lymphocyte proliferation, T-lymphocyte subsets and cytokines in the splenocytes of a mouse
model was carried out after stimulation with the candidate Salmonella
Typhimurium by intranasal inoculation. The splenic lymphocyte proliferation and the levels
of IL-4, IL-6 and IL-12 of the inoculated mice were significantly increased, and the T-
and B-cell populations were also elevated. Collectively, the candidate may efficiently
induce the Th1- and Th2-type immune responses. 相似文献
127.
Stochasticity dominates assembly processes of soil nematode metacommunities on three Asian mountains
Shuqi ZOU Jonathan ADAMS Zhi YU Nan LI Dorsaf KERFAHI Binu TRIPATHI Changbae LEE Teng YANG Itumeleng MOROENYANE Xing CHEN Jinsoo KIM Hyun Jeong KWAK Matthew Chidozie OGWU Sang-Seob LEE Ke DONG 《土壤圈》2023,33(2):331-342
Nematodes play an important role in ecosystems; however, very little is known about their assembly processes and the factors influencing them. We studied nematode communities in bulk soils from three Asian mountain ecosystems to determine the assembly processes of free-living nematode metacommunities and their driving factors. On each mountain, elevations span a range of climatic conditions with the potential to reveal assembly processes that predominate across multiple biomes. A phylogenetic nu... 相似文献
128.
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130.
Six soils on glacial outwash terraces and one on moraine are discussed; four are formed partly in loess of unknown age. Evidence of podzolization is apparent in all profiles, but the vertical drainage under very high rainfall is insufficient to remove surplus water. Gley processes appear to dominate, in a perched-water environment.
Podzolic B horizons were identified in the same five profiles following both the Canadian system and that used by the Soil Survey of England and Wales. However, only three of these profiles could be allocated to existing podzolic subgroups in the latter system. Spodic horizons were identified in a different group of five profiles. Differences in classification are discussed with reference to the criteria used and in relation to proposals for revision of the New Zealand Soil Classification. 相似文献
Podzolic B horizons were identified in the same five profiles following both the Canadian system and that used by the Soil Survey of England and Wales. However, only three of these profiles could be allocated to existing podzolic subgroups in the latter system. Spodic horizons were identified in a different group of five profiles. Differences in classification are discussed with reference to the criteria used and in relation to proposals for revision of the New Zealand Soil Classification. 相似文献