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1.
Tooth root and root trunk surface area measurements were taken from 20 first mandibular molar (M1) teeth obtained randomly from canine cadaver specimens. The mean root surface area for all teeth was 497.1 +/- 116.2 mm2. The cumulative surface areas of the mesial (MR) and distal (DR) roots were 251.4 +/- 70.2 mm2 and 211.7 +/- 51.9 mm2, respectively. The root trunk surface area was 34.0 +/- 21.4 mm2. Surface area measurements for individual roots and the root trunk were significantly different. Cumulative individual root surface area (MR + DR) was 93.2% of total root surface area. The MR surface area contributed most to total root surface area (50.6%) and cumulative individual root surface area (54.3%). The mean distance from the beginning of the root trunk to the furcation was 2.1 mm. On the basis of the linear variation of the percentage of root surface area of the M1, 44.6% of the total root surface area was 3 to 7 mm apical to the most coronal aspect of the cementoenamel junction. The MR was heart-shaped, compared with the more cylindrical shape of the DR.  相似文献   

2.
Monitoring surface conditions of a Thoroughbred racetrack   总被引:2,自引:0,他引:2  
During a pilot study at a Thoroughbred racetrack, information was collected to include weather conditions and track surface properties (moisture content, composition, strength, and coefficient of friction between surface and hoof). Measured weather variables did not correlate to any pattern of horse injuries of breakdowns. Surface moisture content was variable, whereas the moisture content of the compacted cushion was constant. Track surfaces around the starting chutes were more compacted than were other areas of the track. Next to the rail, track surface was softer than the surface toward the middle of the track. The coefficient of friction between a hoof and the surface was not affected by location or surface moisture content.  相似文献   

3.
基于无人机的高寒草甸地表温度监测及影响因素研究   总被引:1,自引:0,他引:1  
地表温度直接影响地表感热、潜热及辐射能量传输过程,是研究寒区植被生态水文过程的重要参数。以疏勒河源区高寒草甸为研究对象,利用无人机搭载普通及热红外相机获取6块样地植被盖度及地表温度数据,用以评估热红外相机在高寒草甸地表温度监测中的应用精度,分析高寒草甸地表温度变化特征,并结合气象因子及植被盖度数据,探究地表温度的影响因素。结果表明:热红外影像地表温度与地面实测值具有较高一致性(R2 ≈ 0.75),平均误差5 ℃以内;高寒草甸地表温度在9: 00-18: 00时段内表现为快速升温达到峰值继而波动下降的趋势,观测期内(7月4日-8月17日)未表现出显著日际变化趋势;气象因子中,太阳辐射和空气温度与地表温度呈显著正相关,起到增温作用,而空气湿度抑制地表增温,表现为显著负相关;连续降水降低裸土温度,植被覆盖度与地表温度呈现出正相关变化趋势。无人机热红外遥感技术可以快速、精准获取高分辨率地表温度数据,为高寒草甸干旱监测、土壤水分及蒸散发等反演提供数据支持。  相似文献   

4.
Skin and rectal temperature measurements were taken on 15 crossbred sows and gilts (225 kg) during the last 5 days of prepartum period and compared with those recorded in the first 8 days after parturition. The correlation of skin and rectal temperature values was not good during either period, although an increased correlation was noted in the postparturient period. The rectal temperature significantly (P less than 0.05) increased in the postparturient period, but the mean surface temperature was unchanged. This would indicate a decreased blood flow to the surface, since an equivalent blood flow to the surface after a rectal temperature increase would result in a concomitant mean surface temperature increase. The decreased flow to the surface of the animal was selective, since a significant (P less than 0.05) decrease in surface temperature was noted at the tailhead, perineum, vulva, mammae-caudal, and eye, whereas the surface temperature of the mammae-cranial and mammae-middle was significantly (P less than 0.05) increased.  相似文献   

5.
A total of 53 Staphylococcus aureus strains isolated from caprine mastitis were tested for surface hydrophobicity, surface Protein A (SpA), and binding capacity of fibronectin, fibrinogen and type II collagen. Strong positive correlation was found between surface hydrophobicity and SpA, and between surface hydrophobicity and 125I-fibronectin-binding. Regardless of hydrophobicity, the binding of fibrinogen was moderate and type II collagen binding was low. The results indicate that SpA and fibronectin-binding protein contribute to the high relative surface hydrophobicity of S. aureus associated with caprine mastitis.  相似文献   

6.
Tooth root and root trunk surface area measurements were made on 20 permanent fourth maxillary premolar (P4) teeth randomly harvested from canine cadaver specimens. Mean root surface area for all 20 teeth was 562.8 +/- 124.9 mm2. Cumulative surface areas of the mesiopalatal, mesiobuccal, and distal roots were 113.8 +/- 29.0 mm2, 138.5 +/- 34.6 mm2, and 180.8 +/- 39.9 mm2, respectively. The mesial root trunk and distal root trunk surface areas were 60.0 +/- 17.5 mm2 and 72.1 +/- 33.2 mm2, respectively. There was not a significant difference between the root surface area of the mesial root trunk and distal root trunk; however, all other root surface area measurements were significantly different (P less than 0.01). Cumulative individual root surface area (distal root + mesiobuccal root + mesiopalatal root) was 76% of total root surface area. The distal root surface area contributed most to total root surface area (32.1%) and cumulative individual root surface area (41.7%). Observation of the linear variation of percentage of root surface area revealed 40.8% of the total root surface area to be in the portion located between 5 and 9 mm apical to the most coronal aspect of the cementoenamel junction. The mesiobuccal root and distal root were cylindrical compared with the flattened, concave shape of the mesiopalatal root.  相似文献   

7.
Lipid globules in the white and brown adipose tissues in the rat were well preserved with prolonged postfixation in OSO4. The difference between the surface of white adipose tissue and that of brown adipose tissue was observed in such a way that the surface of the brown adipocyte was lumpy owing to the presence of intracellular lipid globules, and that the surface of the white adipocyte was considerably smooth. After the matrix of lipid globules was dissolved during specimen preparation, the subgranules embedded in the matrix were disclosed on the inner surface of the lipid globules. The cut surface of the white adipocyte contained a large lipid droplet and the amount of cytoplasm was poor, whereas the brown adipocyte had several lipid droplets and many small granules in the cytoplasm.  相似文献   

8.
Normal canine hip cartilage was compared with cartilage from the degenerative lesions found in young dogs with canine hip dysplasia. The upper 0.5 mm of normal cartilage was characterized. Four distinct layers or zones were found: a layer of fine fibrous material covering the surface, a layer (surface layer) of small (32 nm diameter or less) collagen fibrils tightly packed in bundles and oriented parallel to the surface, a layer (upper layer) or less tightly packed collagen fibrils oriented mostly parallel to the surface with about 33% of the fibrils 64 nm or more, and a layer (intermediate layer) of randomly oriented fibrils with more than 50% of the fibrils 64 nm or larger. Fibril density was high in the surface layer and decreased with depth into the cartilage. In a moderately advanced lesion of degenerative cartilage, there was a layer of amorphous material over the surface. The tightly packed surface layer of small fibrils was absent. The surface itself was uneven and fissued. At depths from the surface comparable to the upper and the intermediate layers in normal cartilage, the proportion of large fibrils was less than in normal cartilage. The overall density of fibrils in degenerative cartilage increased with depth into the tissue. Cells flattened parallel to the surface, with relatively large nuclei, were found in the upper layer of normal cartilage. Cells in the intermediate layers were larger and round. The oblong cells of the upper layer of normal cartilage were not found in any layer of degenerative cartilage. Differences between cells in other layers of normal and degenerative cartilages were minimal. A model for the arrangement of chondrocytes and collagen fibrils for normal and degenerative cartilage was proposed. Ultrastructural changes in degenerative cartilage were prominent in the upper 0.5 mm of cartilage. These changes were changes in the number of collagen fibrils/mum-2 and a change from a characteristic pattern of collagen fibril diameters and orientation found in normal tissue.  相似文献   

9.
Forelimb surface temperatures were continuously monitored in four clinically normal ponies exposed to: (i) constant ambient temperature; (ii) a biphasic change in ambient temperature; and (iii) an incremental increase in ambient temperature. Limb surface temperatures were recorded at the hoof, metacarpus and forearm, and rectal temperature was also measured. Under constant ambient temperature, limb surface temperatures remained relatively constant. A pyrexic episode occurred in one pony under constant ambient temperature conditions and was characterised by an onset phase in which rectal temperature gradually increased while limb surface temperatures concurrently decreased; a plateau phase in which rectal temperature was elevated but essentially constant although limb surface temperatures rose dramatically; and a febrilytic phase in which limb surface temperatures remained elevated while rectal temperature gradually decreased. A biphasic change in ambient temperature produced corresponding changes in limb surface temperature, but limb surface temperatures were less stable at the lower ambient temperatures. Surface temperature responses to incremental increases in ambient temperature were dependent on the baseline ambient temperature (before increase), and dramatic, spontaneous increases in limb surface temperatures were observed. Rectal temperatures in the normal animals remained relatively constant under all three ambient temperature regimens. It was concluded that clinical interpretation of limb surface temperatures in ponies required an awareness of ambient temperature conditions. For evaluation of vasodilator agents, constant ambient temperatures of at least less than 18 degrees C are suggested, and constant ambient temperatures exceeding 20 degrees C are recommended for the evaluation of vasoconstrictor agents.  相似文献   

10.
为了探讨1日龄大通牦牛骨骼肌组织学特点及对低氧的适应,以平原黄牛为对照,利用光镜和计算机图像分析系统测定骨骼肌肌纤维直径、表面积密度;通过透射电镜比较骨骼肌线粒体的面数密度、面积密度、体积密度、平均体积等结构参数。结果显示,1日龄大通牦牛骨骼肌肌纤维直径显著细于1日龄平原黄牛,表面积密度明显大于平原黄牛,差异极显著(P<0.01);1日龄大通牦牛骨骼肌细胞中线粒体平均体积小于1日龄平原黄牛,并具有极显著差异(P<0.01);而1日龄大通牦牛骨骼肌细胞中线粒体体积密度、面积密度、面数密度均大于1日龄平原黄牛,且差异极显著(P<0.01)。以上结果表明,大通牦牛通过增加骨骼肌线粒体面数密度、面积密度、体积密度,降低线粒体平均体积来提高其在低氧环境中对氧的利用,并且在长期进化中形成了肌纤维直径小,表面积密度大的组织学特点。  相似文献   

11.
Although ovine tonsils play a major role in prion diseases, their morphology is poorly documented and morphometric data are sparse. Therefore, a stereological assessment of the surface area of the palatine and pharyngeal tonsils of five sheep was performed. The epithelial surface area of both tonsils is considerably increased by the presence of tonsillar crypts and folds. The mean epithelial surface area of the paired palatine tonsil was 7.14 cm(2) and that of the pharyngeal tonsil was 23.5 cm(2). In comparison with the paired palatine tonsil, the volume of the pharyngeal tonsil was almost two times larger, whilst its surface area was more than three times larger.  相似文献   

12.
Results from a previous study indicated that there are specific arena surface characteristics that are associated with an increased likelihood of lameness in dressage horses. It is important to understand what modifiable arena factors lead to these detrimental surface characteristics. The aim of this study was to describe the use of training surfaces and arenas for United Kingdom dressage horses and to investigate any relationships between arena/surface variables and detrimental surface characteristics. Data from a questionnaire returned by 22.5% of all 11,363 registered members of British Dressage were used for the study. Univariate and multivariable logistic regression models were developed with each of the previously identified surface characteristics as dependent variables. Respondents reported that the majority of arenas were privately owned, sized 20 × 40 m and had a sand and rubber surface. The results indicated that wax-coated and sand and rubber surfaces were associated with less detrimental surface properties than sand, sand and PVC, woodchips or grass. Woodchips were most strongly associated with the detrimental characteristic of slipping, and sand with tripping. The findings indicated that any arena surface should have a base, with limestone the recommended surface, and that crushed concrete was best avoided. This information supported previous studies in racehorses that indicated that surface maintenance is essential, especially when many horses are using an arena daily. Problems were less likely if an arena was privately owned.  相似文献   

13.
OBJECTIVE: To determine whether solar load distribution pattern on a solid nondeformable ground surface is the product of contact erosion and is the mirror image of load distribution on a deformable surface in horses. ANIMALS: 30 clinically normal horses. PROCEDURES: Solar load distribution was compared among 25 clinically normal horses during quasistatic loading on a solid nondeformable surface and on a highly deformable surface. Changes in solar load distribution patterns were evaluated in 5 previously pasture-maintained horses housed on a flat nondeformable surface. Changes in solar load distribution created by traditional trimming and shoeing were recorded. RESULTS: Unshod untrimmed horses had a 4-point (12/25, 48%) or a 3-point (13/25, 52%) wall load distribution pattern on a flat solid surface. Load distribution on a deformable ground surface was principally solar and located transversely across the central region of the foot. Ground surface contact areas on solid (24.2 +/- 8.62 cm2) and deformable (69.4 +/- 22.55 cm2) surfaces were significantly different. Maintaining unshod horses on a flat nondeformable surface resulted in a loss of the 3- and 4-point loading pattern and an increase in ground surface contact area (17.9 +/- 2.77 to 39.9 +/- 12.77 cm2). Trimming increased ground surface contact area (24.2 +/- 8.60 to 45.7 +/- 14.89 cm2). CONCLUSION AND CLINICAL RELEVANCE: In horses, the solar surface is the primary weight-loading surface, and deformability of ground surface may have a role in foot expansion during loading. Increased surface area induced by loading on deformable surfaces, trimming, and shoeing protects the foot.  相似文献   

14.
A case of a high-grade surface osteosarcoma in the thoracic limb of a dog is reported. Radiographically, there was no bone involvement but there was increased soft tissue opacity. An aggressive osteosarcoma was diagnosed on the basis of early metastatic disease and histopathological examination. Previously reported surface osteosarcomas in the dog have been periosteal and parosteal osteosarcomas which are generally considered to have a low to intermediate biological activity. The tumour described here had radiographical, gross pathological, histopathological and biological features consistent with human high-grade surface osteosarcoma. The characteristics of surface osteosarcomas are briefly reviewed.  相似文献   

15.
Polarized light biomicroscopy was used to examine the pre-corneal tear film in 16 dogs which were suspected of, or confirmed to be, suffering from keratoconjunctivitis sicca. One animal displayed a normal tear film, while the other 15 showed variable degrees of abnormality. The abnormal features included: contamination of the ocular surface with particulate debris and plaques of mucus, discontinuity and excessive granularity of the surface lipid film, pronounced thinning of the aqueous phase, and breakup of the tear film. After parotid duct transposition, the tear film of some animals was almost indistinguishable from normal. However, in others the surface lipid layer was thinned, discontinuous, or virtual absent. Discontinuity of surface lipid was most obvious in animals with marked salivary epiphora, and was associated with a variable amount of crystalline concretion over the ocular surface. The clinical usefulness of polarized light biomicroscopy for the diagnosis, and subsequent monitoring, of keratoconjunctivitis sicca is discussed.  相似文献   

16.
为了揭示布鲁氏菌病的致病机制并研制其新型分子疫苗,试验利用酿酒酵母展示系统展示绵羊白细胞表面抗原DRB1基因,构建DRB1基因外显子2的酵母表面展示库。参照GenBank中绵羊MHC Ⅱ DRB1基因序列设计引物,以绵羊脾脏组织cDNA为模板,反转录扩增得到预期长度的产物,双酶切连接到克隆载体pEASY-T1,命名为pEASY-T1-DRB1。双酶切连接到表面展示载体pYD1上,成功构建了表面展示重组质粒pYD1-DRB1。以pEASY-T1-DRB1为模板,将DRB1基因外显子2两端进行点突变,产生新的酶切位点,然后对外显子2设计特异性引物。对500个绵羊样本进行DNA池化,扩增DRB1基因外显子2序列,双酶切后连接到经相同酶双酶切的表面展示重组突变载体pYD1-DRB1-TB上,构建酿酒酵母表面展示库。转化大肠杆菌DH5α感受态细胞,计算库容量。将其转化酿酒酵母EBY100感受态细胞,经半乳糖诱导,通过免疫荧光法在荧光显微镜下检测。结果显示,绵羊DRB1基因成功整合到酵母基因组中,酵母展示库的库容量在105个以上,DRB1基因库成功展示在酵母细胞表面。由此说明,该库可用于下一步布鲁氏菌抗原肽的筛选。  相似文献   

17.
Screw and laser (SL) column by making screw threads and forming small holes using laser irradiation on the base metal and conventional beads coating (BC) columns were embedded into the shaft of canine femurs, and compared the implant fixation to the host bone. The interfacial strength in SL columns was almost equivalent as BC columns, and bone-column contact rate was higher than BC columns significantly at twelve weeks after implantation. The newly devised SL surface had almost equivalent bone fixation strength comparable to the conventional BC surface. Also, this surface should provide a useful porous surface for use in artificial joints since there is no risk of surface structure detachment.  相似文献   

18.
The lizard Angolosaurus skoogi inhabits the surface and subsurface environments of sand dunes of the northern Namib Desert. We have related posture, locomotion, and other aspects of surface activity to the microclimate prevailing above and below the surface. Globe temperature was the best microclimatic correlate of surface activity. From our analysis, we concluded that surface thermoregulatory behaviour of A. skoogi is facultative, and aimed at maintaining a body temperature compatible with foraging and other obligatory surface activities.  相似文献   

19.
Mucosa obtained from the cecum of healthy horses and incubated in vitro with 0.1 mM cycloleucine could accumulate this amino acid against an apparent concentration gradient after 60 and 120 minutes. Accumulation by the serosal (antiluminal) surface of the tissue was 3 times greater than accumulation by the mucosal (luminal) surface after 120 minutes (P less than 0.001). Cycloleucine accumulation was significantly reduced by Na deprivation after 60 minutes (P less than 0.05) and 120 minutes (P less than 0.01) and by anoxic conditions after 120 minutes (P less than 0.05). Transmucosal flux from mucosal to serosal surface of the tissue was significantly (P less than 0.05) greater than the opposing flux, but both unidirectional fluxes were small and were largely attributed to passive processes. It was concluded that the most avid transport system for cycloleucine was on the serosal surface of the horse's cecal mucosa, and an active transport system was not evident on the mucosal surface. An active transport system for amino acids on the serosal surface could be explained by the need for crypt cells, the predominant epithelial cell type in the cecum, to obtain nutrients from blood, rather than from the intestinal lumen.  相似文献   

20.
柔嫩艾美耳球虫EtMIC2的酵母表面展示   总被引:1,自引:0,他引:1  
利用酿酒酵母表面展示系统展示柔娥艾美耳球虫微线蛋白基因EtMIC2,为下一步研制活裁体疫苗奠定基础。参照GenBank中柔嫩艾美耳球虫EtMIC2基因序列设计引物,以柔嫩艾美耳球虫的RNA为模板,利用RT—PCR扩增得到预期长度的产物,双酶切连接到酿酒酵母表面展示的载体pCTCON2,转化大肠杆菌TOPl0,提取阳性质粒转化酿酒酵母菌株EBYl00,诱导表达后,用抗EtMIC2蛋白质特异性抗体,做间接免疫荧光(IFA)检测EtMIC2蛋白的表达。结果显示,EtMIC2成功展示到酵母细胞表面,测得最佳诱导时间为48h。  相似文献   

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