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941.
固化茧丝的丝胶稳定性及染色性直接关系丝胶固着丝绸产品的市场开发前景。通过测定丝胶溶失率、耐洗涤性能和上染率及红外光谱,研究了固化茧丝的丝胶稳定性及适用的染料和部分染色工艺条件。检测结果表明固化茧丝的丝胶溶失率比普通茧丝低,丝胶性能稳定,90℃条件下固化茧丝的丝胶溶失率只有1.6%;红外光谱显示固化茧丝的分子结构发生了一定改变;活性染料和酸性染料对固化茧丝的上染试验显示酸性染料的上染率高于活性染料,但其染色均匀性不及活性染料,活性染料和酸性染料对固化茧丝的最高上染率分别为67.9%、68.5%;适宜固化茧丝纤维上染的温度为70℃,用酸性染料上染固化茧丝不宜采用强酸性浴。 相似文献
942.
943.
石羊河上游退化草地植物功能群生态位分异特征——以阿尔泰狗哇花型草地为例 总被引:2,自引:1,他引:2
采用时空转换方式,以石羊河上游高山草地阿尔泰狗哇花Heteropappus altaicus型退化草地及其原生群落为研究对象,以其主要功能群结构特征调查为基础,研究各功能群生态位季节动态特征。结果表明:该区生态位季节动态变化趋势同功能群类别有关,与功能群所处的演替阶段无关;功能群生态位数量特征变化的绝对数量及相对数量受到其所处的演替阶段影响,表现为随季节的推移禾本科功能群生态位宽度上升,其上升相对值为退化样地(120.8%)高于原生群落(65.5%);而杂类草下降,其下降相对值差异较小,依次为51.38%和66.34%。随季节的推移禾本科-杂类草生态位重叠度升高,且升高的幅度为退化样地(113.3%)略低于原生群落(119.4%),就升高的绝对值而言,原生群落各观测时期均低于退化草地;杂类草-禾本科生态位重叠度则逐渐降低,其相对数量在退化样地与原生群落中依次下降53.0%和54.9%。其中退化草地禾本科、杂类草生态位重叠度在7月中旬存在一个拐点,其前期禾本科-杂类草组对低于杂类草-禾本科组对,而后期刚好相反。造成上述现象的原因可能与功能群生长特性和放牧干扰共同作用有关。返青较早的禾本科功能群早期生长受到放牧干扰的影响,为返青较迟的杂类草生长提供较大的资源空间,从而使得杂类草功能群在“植被空隙中进行季节更新”,进而改变了原群落的功能群结构。阿尔泰狗哇花型退化草地是植物群落退化演替过程中的关键阶段,如果加以适当的管理,草原退化将得到一定程度的改善;如果不加以保护,草地继续退化后的不可预知风险将提高。 相似文献
944.
猪传染性胃肠炎临床诊断及防治 总被引:1,自引:0,他引:1
猪传染性胃肠炎是由猪传染性胃肠炎病毒引起的急性高度接触性肠道传染病,临床上以腹泻、呕吐和脱水为特征,各种年龄的猪都可发病,对哺乳仔猪的危害最严重.然而以腹泻为主症的还有猪痢疾、仔猪黄痢、仔猪白痢、仔猪红痢(梭菌性肠炎)、流行性腹泻、轮状病毒感染、仔猪副伤寒等7种疫病,为了更有效地防控猪传染性胃肠炎,做到早诊断、早治疗.论文阐述了猪传染性胃肠炎与猪其他7种腹泻疫病的临床症状的区别及猪传染性胃肠炎的防治要点. 相似文献
945.
946.
以恩诺沙星为原料,纯化水为溶媒,利用胶体磨采用分散法研制出恩诺沙星口服混悬液,并对制剂进行了稳定性研究.结果显示,所有参试样品的外观性状、沉降体积比、再分散性、相对含量等指标均无明显变化,表明该制剂稳定性良好.结果表明,试验组与对照组对仔猪黄白痢的治愈率分别为72.0%和66.0%,有效率分别为92.0%和72.0%,试验组对仔猪黄白痢的有效率与对照组比较差异极显著(P<0.01),表明恩诺沙星口服混悬液对仔猪黄白痢的临床疗效显著优于恩诺沙星溶液. 相似文献
947.
抗生素对胃肠道微生态系的影响与对应举措 总被引:1,自引:0,他引:1
文章阐述抗生素对家畜胃肠道微生态系的影响与对应举措.凡进入家畜胃肠道的抗生素不仅可抑杀有害菌群、中性菌群,同时亦可抑杀有益菌群,破坏微生态系的生理组合等问题.提出了研发抗生素替代物的依据,指出中草药是理想的抗生素替代产品. 相似文献
948.
Dorsal displacement of the soft palate is an important cause of poor performance in racehorses, yet its etiology is not fully understood. Diagnosis requires treadmill videoendoscopy, which is not widely available. The relationship of the larynx, the hyoid apparatus, and the remainder of the skull may be important in predisposing horses to dorsal displacement of the soft palate. We hypothesized that this relationship could be accurately assessed in unsedated horses through ultrasonographic examination. Fifty-six racehorses presented for evaluation of poor performance were subjected to treadmill videoendoscopy and resting ultrasonography. Using ultrasound-assisted percutaneous measures of laryngo-hyoid position, the relationship between selected anatomic structures and the occurrence of dorsal displacement of the soft palate was evaluated. A significant relationship was found between the depth of the basihyoid bone at rest and the occurrence of dorsal displacement of the soft palate at exercise ( P =0.03). Other measures of laryngohyoid position were not found to be associated with dorsal displacement of the soft palate. Thus, there is an association between the occurrence of dorsal displacement of the soft palate at exercise and the resting position of the basihyoid bone, whereby on average a more ventral location of the basihyoid bone is present in horses with dorsal displacement of the soft palate. The pathophysiologic implications of this finding are not fully understood but, based on our findings, ultrasound examination is of value in assisting in the diagnosis of dorsal displacement of the soft palate. 相似文献
949.
950.
Amy M. Schwartz Manjunath B. Shankar Kiersten J. Kugeler Ryan J. Max Alison F. Hinckley Martin I. Meltzer Christina A. Nelson 《Zoonoses and public health》2020,67(4):407-415
An estimated 300,000 cases of Lyme disease occur in the United States annually. Disseminated Lyme disease may result in carditis, arthritis, facial palsy or meningitis, sometimes requiring hospitalization. We describe the epidemiology and cost of Lyme disease‐related hospitalizations. We analysed 2005–2014 data from the Truven Health Analytics MarketScan Commercial Claims and Encounters Databases to identify inpatient records associated with Lyme disease based on International Classification of Diseases, Ninth Revision, Clinical Modification (ICD‐9‐CM) codes. We estimated the annual number and median cost of Lyme disease‐related hospitalizations in the United States in persons under 65 years of age. Costs were adjusted to reflect 2016 dollars. Of 20,983,165 admission records contained in the inpatient databases during the study period, 2,823 (0.01%) met inclusion criteria for Lyme disease‐related hospitalizations. Over half of the identified records contained an ICD‐9‐CM code for meningitis (n = 614), carditis (n = 429), facial palsy (n = 400) or arthritis (n = 377). Nearly 60% of hospitalized patients were male. The median cost per Lyme disease‐related hospitalization was $11,688 (range: $140–$323,613). The manifestation with the highest median cost per stay was carditis ($17,461), followed by meningitis ($15,177), arthritis ($13,012) and facial palsy ($10,491). Median cost was highest among the 15‐ to 19‐year‐old age group ($12,991). Admissions occurring in January had the highest median cost ($13,777) for all study years. Based on extrapolation to the U.S. population, we estimate that 2,196 Lyme disease‐related hospitalizations in persons under 65 years of age occur annually with an estimated annual cost of $25,826,237. Lyme disease is usually treated in an outpatient setting; however, some patients with Lyme disease require hospitalization, underscoring the need for effective prevention methods to mitigate these serious cases. Information from this analysis can aid economic evaluations of interventions that prevent infection and advances in disease detection. 相似文献