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31.
We performed biomechanical comparison of a xenograft bone plate-screw (XBPS) system for achieving cadaveric lumbar transpedicular stabilization (TS) in dogs. Twenty dogs'' cadaveric L2-4 lumbar specimens were harvested and their muscles were removed, but the discs and ligaments were left intact. These specimens were separated to four groups: the L2-4 intact group as control (group I, n = 5), the L3 laminectomy and bilateral facetectomy group (LBF) (group II, n = 5), the LBF plus TS with metal plate-screw group (group III, n = 5) and the LBF plus TS with XBPS group (group IV, n = 5). Five kinds of biomechanical tests were applied to the specimens: flexion, extension, left-right bending and rotation. The averages of the 16 stiffness values were calculated and then these were statistically analyzed. The statistical results show that the XBPS system contributes spinal stability and this system can be a good choice for achieving TS.  相似文献   
32.
Monosex populations can be a valuable management tool in culture of larger size largemouth bass (>400 g). In this study, we investigated the effective mode and duration of oestrogen and androgen administrations to produce monosex largemouth bass populations. The experiment consisted of nine treatments. In oral administration groups, we fed 40-day-old fry either 200 mg of an oestradiol-17β (E2) kg−1 diet or 60 mg of a 17α-methyltestosterone (MT) kg−1 diet for 30, 45 or 60 days. In bath treatments, we immersed fry in a 1 mg MT L−1 solution for 5 h a day on three or six occasions. For control treatment, we fed fry an ethanol-treated diet for 45 days. The frequency of females in the control group was 53.1%. Oral administration of E2 at all durations resulted in slight increases in the frequency of females (59.8–70.5%). Both modes of androgen administration at all durations were ineffective in altering phenotypic sex. The experimental results of our study indicated that male differentiation passed the point of being completely and functionally influenced by exogenous oestrogens, while female differentiation had already taken place and was no longer responsive to exogenous androgens in 40-day-old (33.5 mm) largemouth bass fry.  相似文献   
33.
Ornithogalum ulophyllum Hand.-Mazz. with beautiful white flowers is an important medicinal and ornamental plant of the Middle Eastern countries and need exploitation for commercial propagation. The study reports in vitro mass proliferation of bulblets achieved from twin scales and “in vitro regenerated bulblet” explants on MS medium supplemented with various concentrations of BAP–NAA. The best regeneration on twin scales and “in vitro regenerated bulblets” was obtained on MS medium containing 2 mg l−1 BAP–0.5 mg l−1 NAA and 2 mg l−1BAP–1 mg l−1 NAA, respectively. However, bulb scales seemed to be more potent for bulblet regeneration. A large number of the developing bulblets rooted on the regeneration medium. Remaining non-rooting bulblets were rooted on MS medium containing 1 mg l−1 NAA. All plants were acclimatized in the environmental chamber for 4 weeks and were transferred to the greenhouse for flowering. Regenerated bulblets developed into morphologically normal plants.  相似文献   
34.
To control postharvest decay, table grapes are commercially fumigated with sulfur dioxide. We evaluated ozone (O3) fumigation with up to 10,000 μL L?1 of ozone for up to 2 h to control postharvest gray mold of table grapes caused by Botrytis cinerea. Fumigation for 1 h with 2500 or 5000 μL L?1 of ozone were equal in effectiveness. Both treatments reduced postharvest gray mold among inoculated ‘Thompson Seedless’ grapes by approximately 50% when the grapes were examined after storage for 7 d at 15 °C following fumigation. In a similar experiment, ‘Redglobe’ grapes were stored for 28 d at 0.5 °C following fumigation for 1 h with 2500 or 5000 μL L?1 of ozone. Both treatments were equal in effectiveness, but inferior to fumigation with 10,000 μL L?1. Ozone was effective when grapes were inoculated and incubated at 15 °C up to 24 h before fumigation. The cluster rachis sustained minor injuries in some tests, but berries were never harmed. Ozone was applied in three combinations of time and ozone concentration (10,000 μL L?1 for 30 min, 5000 μL L?1 for 1 h, and 2500 μL L?1 for 2 h) where each had a constant concentration × time product (c × t) of 5000 μL L?1 × h. The effectiveness of each combination was similar. The incidence of gray mold was reduced by approximately 50% among naturally inoculated, organically grown ‘Autumn Seedless’ and ‘Black Seedless’ table grapes, and by 65% among ‘Redglobe’ table grapes, when they were fumigated with 5000 μL L?1 ozone for 60 min in a commercial ozone chamber and stored for 6 weeks at 0.5 °C. Residues of fenhexamid, cyprodinil, pyrimethanil, and pyraclostrobin were reduced by 68.5, 75.4, 83.7, and 100.0%, respectively, after a single fumigation of table grapes with 10,000 μL L?1 ozone for 1 h. Residues of iprodione and boscalid were not significantly reduced. Ozone is unlikely to replace sulfur dioxide treatments in conventional grape production unless its efficacy is improved, but it could be an acceptable technology to use with grapes marketed under “organic” classification, where the use of SO2 is prohibited, or if SO2 use were to be discontinued.  相似文献   
35.
[目的]利用核糖体DNA(nrDNA)ITS序列和叶绿体DNA(cpDNA)psbA-trnH序列对云南不同地理区域的黄毛草莓进行分子鉴定,并分析不同地理居群间的分子进化及地理分布特征,为黄毛草莓种质鉴定、保护及开发利用提供理论依据.[方法]以云南省12个不同地理区域的黄毛草莓居群样品为材料,PCR扩增其ITS和psbA-trnH序列,并进行双向测序及序列合并,分别基于ITS和psbA-trnH序列及二者合并序列构建系统发育进化树.最后利用DnaSP 5.10对ITS和psbA-trnH序列进行核苷酸多样性(π)及单倍型数目、类型和多样性(Hd)分析,并对黄毛草莓居群进行中性检验及分子进化特征分析.[结果]基于ITS和psbA-trnH序列的聚类分析结果均显示,12个不同地理区域的黄毛草莓居群样品均与GenBank数据库中下载的黄毛草莓聚在一个分支上,分支自展值均大于阈值(75%),表明这两种序列均可用于黄毛草莓种质的分子鉴定.基于二者合并序列的聚类分析结果与上述结果基本一致,但分支自展值达99%,表明该聚类分析结果更可靠.不同地理区域的黄毛草莓ITS序列间的遗传距离为0~0.014,排序为迪庆州>昆明市>文山州,psbA-trnH序列间的遗传距离为0~0.025,排序为昆明市>迪庆州>文山州,推测ITS和psbA-trnH序列均能显示黄毛草莓居群遗传分化与地理分布格局的相关性.ITS序列长度为668 bp,变异位点百分率为1.8%,共有8种单倍型,Hd和π分别为0.894±0.078和0.006,以昆明市黄毛草莓样品的单倍型最多,为4种;psbA-trnH序列有203 bp,变异位点百分率为2.5%,psbA-trnH序列共有5种单倍型,Hd和π分别为0.788±0.090和0.009,以昆明市黄毛草莓样品单倍型最多,为3种,表明两种序列的单倍型均呈现地理分布格局.黄毛草莓ITS和psbA-trnH序列的中性检验Tajima's D值分别为-0.673和0.227(P>0.1),表明云南省12个不同地理区域的黄毛草莓居群保持稳定状态,在截至目前的历史时间内不存在扩张.[结论]从云南不同地理区域采集的样品均为黄毛草莓.ITS序列和psbA-trnH序列均可作为黄毛草莓的DNA条形码,二者的合并序列更能准确鉴定黄毛草莓种,适用于黄毛草莓分子谱系地理学研究.  相似文献   
36.
37.
This study was designed to evaluate the effectiveness of recombinant Ovalbumin-LHRL (OL) immunization on changes in testicular size, histological appearance and testosterone production in buck kids. Thirty native buck kids at 18 weeks of age were divided into three groups, control (n = 10), immunization (n = 10) and castration (n = 10) groups. Immunized animals received OL protein generated by recombinant DNA technology. Ultrasonographic and histological examinations of the testes were performed. Animals were slaughtered at 44 weeks of age. Semen and epididymides were evaluated for the presence of sperm cells. Immunized animals generated anti-LHRH antibodies. Testosterone production, testicular and accessory glands development and sperm production were suppressed in the immunized animals (p < 0.01). Semineferous tubule diameters decreased (p < 0.01), basal membrane of the tubule was thickened and hyalinized in immunized kids. Immunization affected ultrasonographic appearance of the testes drastically. While testes of control animals gained their normal ultrasonographic appearance as the age increased, immunized animals had uniform hypoechogenic testicular structure as observed at 18 weeks of age until slaughter. Simultaneous histological and ultrasonographic evaluations indicated that the changes in testicular histology could partly be monitored via ultrasonographic imaging; nevertheless, it is difficult to claim that ultrasonographic image reflects the exact changes in such instances. In conclusion, these results indicate that recombinant OL fusion protein is effective in immunocastration in buck kids and has a potential to be used as an alternative to physical castration. Further researches should be conducted to help assessing reproductive status of testes from ultrasound images.  相似文献   
38.
1. The aim of the present study is to describe, immunohistochemically, the expression and cell type localisation of growth factor receptors and some of their ligands in the oropharyngeal organs of the Chukar partridge.

2. The tissue samples from 10 healthy adult partridges were dissected under ether anaesthesia and then embedded in paraffin following routine histological procedures. The immunoreaction for receptors and ligands of the epidermal growth factor receptor (EGFR)/ligand system was localised in the cell membrane, nucleus and cytoplasm of the luminal and glandular epithelial cells, stromal and striated muscle cells, and vascular endothelial and smooth muscle cells.

3. Variations were observed in the avian oropharyngeal organs. The immunostaining for the erbB1/HER1 (human epidermal growth factor receptor 1) and the EGF (epidermal growth factor) and AREG (Amphiregulin) ligands in the luminal epithelial cells was higher than in the glandular epithelial, stromal and striated muscle cells. However, the immunostaining for erbB3/HER3 (human epidermal growth factor receptor 3) and erbB4/HER4 (human epidermal growth factor receptor 4) were similar in the luminal epithelium, stromal and striated muscle cells.

4. Growth factor receptors and some of their ligands were localised in different cell types in the oropharyngeal organs. We suggest that erbB/HERs (human epidermal growth factor receptors) and their ligands play an important role in proliferation, differentiation, growth, survival and migration of the cells.  相似文献   

39.
The experiment aimed at evaluating the yield and quality response of broccoli (Brassica oleracea L. var. italica) to applied irrigation water and nitrogen by drip irrigation method during the spring and autumn cultivation periods of 2007. Irrigation water was applied based on a ratio of Class A pan evaporation (kcp = 0.50, 0.75, 1.00 and 1.25) with 7 days interval. Also, the effect of four nitrogen levels (0 kg ha−1, 150 kg ha−1, 200 kg ha−1 and 250 kg ha−1) was compared with each treatment. The seasonal evapotranspiration in the treatments varied from 233 mm to 328 mm during the spring period and from 276 mm to 344 mm during the autumn period. The highest broccoli yield was obtained in the spring period as 11.02 t ha−1 and in the autumn period as 4.55 t ha−1. In general, there were statistical differences along nitrogen does with respect to yield and yield components while there were no statistically significant differences in the yield and yield components among irrigation regimes. Both yield and yield parameters in the spring period were found to be higher than that of the autumn period due to the low temperature and high rainy days in autumn. Irrigation water use efficiency (IWUE) ranged from 3.78 kg m−3 to 14.61 kg m−3 during the spring period and from 1.89 kg m−3 to 5.93 kg m−3 during the autumn period. On the other hand, nitrogen use efficiency (NUE) changed as 37.32-73.13% and 13.08-22.46% for spring and autumn season, respectively.  相似文献   
40.
Regulatory approval of ozone has increased commercial interest in the development of applications to ensure produce quality and safety. However, ozone sometimes fails to inactivate microorganisms on packaged produce and this may be a consequence of poor diffusion into packages. Gaseous ozone (900 ± 12 μL/L) was applied to several common plastic films with a range of ventilation areas and diffusion through them determined. A semi-quantitative method using the reaction of ozone with indigo trisulfonate or with indigo carmine dye solutions was used. Dye de-colorization occurred relatively rapidly (in less than 1 h) after exposure to ozone, indicating that it diffused through all tested materials. Although the extent of ozone diffusion followed the sequence of high-density polyethylene > polypropylene > low density polyethylene, differences among them were small and not significant (P > 0.05). Ozone diffusion was also determined through a low density polyethylene film with ventilation areas of 1.3, 5.2, and 10.4% created by circular holes 6.5 mm in diameter. Gradual but modest increases in ozone diffusion occurred as the ventilation area increased.  相似文献   
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