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991.
Marianne Velandia RNM Ann‐Sofi Matthisen BSc Kerstin Uvnäs‐Moberg MD PhD Eva Nissen RNMTD PhD 《分娩》2010,37(3):192-201
Abstract: Background: Cesarean section is associated with delayed mother‐infant interaction because neither the mother nor the father routinely maintains skin‐to‐skin contact with the infant after birth. The aim of the study was to explore and compare parent‐newborn vocal interaction when the infant is placed in skin‐to‐skin contact either with the mother or the father immediately after a planned cesarean section. Methods: A total of 37 healthy infants born to primiparas were randomized to 30 minutes of skin‐to‐skin contact either with fathers or mothers after an initial 5 minutes of skin‐to‐skin contact with the mothers after birth. The newborns’ and parents’ vocal interaction were recorded on a videotape and audiotape. The following variables were explored: newborns’ and parents’ soliciting, newborns’ crying and whining, and parental speech directed to the other parent and to the newborn. Results: Newborns’ soliciting increased over time (p = 0.032). Both fathers and mothers in skin‐to‐skin contact communicated more vocally with the newborn than did fathers (p = 0.003) and mothers (p = 0.009) without skin‐to‐skin contact. Fathers in skin‐to‐skin contact also communicated more with the mother (p = 0.046) and performed more soliciting responses than the control fathers (p = 0.010). Infants in skin‐to‐skin contact with their fathers cried significantly less than those in skin‐to‐skin contact with their mothers (p = 0.002) and shifted to a relaxed state earlier than in skin‐to‐skin contact with mothers (p = 0.029). Conclusions: Skin‐to‐skin contact between infants and parents immediately after planned cesarean section promotes vocal interaction. When placed in skin‐to‐skin contact and exposed to the parents’ speech, the infants initiated communication with soliciting calls with the parents within approximately 15 minutes after birth. These findings give reason to encourage parents to keep the newborn in skin‐to‐skin contact after cesarean section, to support the early onset of the first vocal communication. (BIRTH 37:3 September 2010) 相似文献
992.
Dermatitis is reported from slimicides added to wood pulp slurry in a paper mill. The active constituents of the slimicides involved were bis-1,4-bromoacetoxy-2-butene and 2,3-dichloro-4-bromotetrahydrothiophene-1,1-dioxide. Wood pulp slimicides include many chemicals which are highly irritant and potentially sensitizing to the skin. 相似文献
993.
Muhammad Rabeel Sofia Javed Ramsha Khan Muhammad Aftab Akram Shania Rehman Deok-kee Kim Muhammad Farooq Khan 《Materials》2022,15(9)
Herein, we synthesized the zinc oxide (ZnO) thin films (TFs) deposited on glass substrates via spray pyrolysis (SP) to prepare self-cleaning glass. Various process parameters were used to optimize photocatalytic performance. Substrates were coated at room temperature (RT) and 250 °C with a 1 mL or 2 mL ZnO solution while maintaining a distance from the spray gun to the substrate of 20 cm or 30 cm. Several characterization techniques, i.e., XRD, SEM, AFM, and UV–Vis were used to determine the structural, morphological, and optical characteristics of the prepared samples. The wettability of the samples was evaluated using contact angle measurements. As ZnO is hydrophilic in nature, the RT deposited samples showed a hydrophilic character, whereas the ZnO TFs deposited at 250 °C demonstrated a hydrophobic character. The XRD results showed a higher degree of crystallinity for samples deposited on heated substrates. Because of this higher crystallinity, the surface energy decreased, and the contact angle increased. Moreover, by using 2 mL solution, better surface coverage and roughness were obtained for the ZnO TFs. However, by exploiting the distance of the spray to the samples size distribution and surface coverage can be controlled, the samples deposited at 30 mL showed a uniform particle size distribution from 30–40 nm. In addition, the photoactivity of the samples was tested by the degradation of rhodamine B dye. Substrates prepared with a 2 mL solution sprayed at 20 cm showed higher dye degradation than other samples, which can play a vital role in self-cleaning. Hence, by changing the said parameters, the ZnO thin film properties on glass substrates were optimized for self-cleaning diversity. 相似文献
994.
Michael Storchak Konstantin Drewle Christian Menze Thomas Stehle Hans-Christian Mhring 《Materials》2022,15(9)
The thermomechanical interaction of the tool with the chip in the most loaded secondary cutting zone depends on the contact length of the tool rake face with the chip. Experimental studies of the dependency of the contact length on the cutting speed, the undeformed chip thickness, and the tool rake angle, performed by the optical method, are used for comparison with the contact length obtained by the FE modeling of the orthogonal cutting process. To determine the parameters of the constitutive Johnson–Cook equation, which serves as a material model of the FE cutting model that has a predominant influence on the contact length, a software-implemented algorithm was developed. This algorithm is based on determining the generalized parameters of the constitutive equation through finding the intersection of these parameter sets. The plurality intersection of the parameter sets of the constitutive equation is determined by means of the design of experiments and refined by subsequent multiple iterations. The comparison of the contact length values, obtained by simulating the cutting process using the generalized parameters of the constitutive equation as a material model with their experimental values, does not exceed 12% for a wide range of cutting speeds and depths of cut, as well as for the tool rake angle. 相似文献
995.
《Ophthalmology》1987,94(10):1310-1314
The adherence of Pseudomonas aeruginosa to extended-wear soft contact lenses (EWSCLs) may be an important initial step in the pathogenesis of EWSCL-associated infectious keratitis. P. aeruginosa tend to adhere more to worn EWSCLs than unworn EWSCLs (P < 0.05). Normal tear components such as aqueous solutions of albumin, lysozyme, and lactoferrin all significantly enhance adherence of P. aeruginosa to unworn EWSCLs often by as much as 300%. The presence of a 1 % solution of sialic acid in the bathing medium significantly reduces the adherence of P. aeruginosa to both unworn and worn lenses. Inhibition of bacterial adherence could also be achieved with the addition of mucin (which contains terminal sialic acid residues in its major sugar chains). Therefore, selective adherence by P. aeruginosa to a specific sugar (sialic acid) may be important in the initial attachment of the bacterium to soft contact lenses. 相似文献
996.
目的:探讨美容相关眼部损伤急性期的临床表现。
方法: 回顾性研究。收集2016-04/2021-10因美容导致的眼部损伤患者53例89眼,分析患者急性期的临床特征,包括性别、年龄、受伤眼别、临床表现、致伤原因、治疗过程及预后。
结果:纳入53例89眼患者均为女性,年龄22-45(平均28.4±6.7)岁。单眼损伤17例,双眼损伤36例。2种或2种以上眼部损伤可累及同一眼。导致眼部损伤的主要美容操作包括:纹眼线38眼(43%); 嫁接睫毛18眼(20%); 去除假睫毛11眼(12%); 涂睫毛膏8眼(9%); 双重睑手术6眼(7%); 其他8眼(9%)。主要眼部损伤类型包括:角膜损伤56眼(63%); 眼睑接触性皮炎26眼(29%); 结膜炎19眼(21%); 眼睑反应性水肿13眼(15%); 眼表异物12眼(14%); 睑缘细菌性感染10眼(11%); 其他5眼(6%),这其中包括因眼周注射玻尿酸导致视网膜中央动脉阻塞1眼(1%)。74眼经过正规治疗可在1-2 wk内痊愈,3眼出现丝状角膜炎,视网膜中央动脉阻塞1眼预后差。
结论:美容相关眼部损伤见于中青年女性,引发眼部损伤最常见的美容操作是纹眼线,最主要损伤类型为角膜损伤。美容相关眼部损伤多数可以预防,治疗方法有效且总体预后良好。 相似文献
997.
目的 探究足踝体外生物力学实验中肌力对足关节接触力、峰值压强以及接触面积的影响,为选择合适的加载方式提供依据。 方法 踝关节中立位状态下,对新鲜小腿和足离体标本分别进行有无肌力两种方式加载,测量加载状态下第 1 跖趾关节、第 2 跖趾关节、第 1 跖楔关节、第 2 跖楔关节、内侧楔舟关节、中间楔舟关节、距舟关节、
跟骰关节、距下关节(后关节面)以及胫距关节的接触力、峰值压强和接触面积,并对结果进行对比分析。 结果 与无肌力加载状态相比,进行肌力加载时足第 1 跖趾关节、第 2 跖趾关节、第 1 跖楔关节、第 2 跖楔关节、内侧楔舟关节、中间楔舟关节、距舟关节和胫距关节的关节接触力均显著增大( P < 0. 05),变化百分比分别为 719. 28%、311. 37%、128. 67%、50. 82%、54. 89%、57. 63%、79. 98% 和 50. 34% ;足第 1 跖趾关节、第 1 跖楔关节和距舟关节的关节峰值压强显著增大(P<0. 05),变化百分比分别为 176. 14%、62. 91% 和 40. 07% ;足第 1 跖趾关节、第 1 跖楔关节、中间楔舟关节以及距下关节(后关节面) 的关节接触面积均显著增大( P < 0. 05),变化百分比分别为 132. 20%、55. 41%、30. 97% 和 26. 87% 。 结论 足踝标本生物力学实验中,进行肌力加载对足各关节的关节接触力、峰值压强或接触面积均产生显著影响,前足表现尤甚。 在进行相关体外标本研究时,需要考虑肌力加载对足踝受力情况的影响,为足踝生物力学实验提供参考。 相似文献
998.
目的 初步探讨碳离子硅橡胶经过不同消毒试剂与方法处理后其表面亲疏水性、表面自由能以及邵氏硬度的变化情况.方法 碳离子硅橡胶经过70%酒精、2%碱性戊二醛、0.5%碘伏、5.25%次氯酸钠、3%过氧化氢以及134℃高温、高压等消毒试剂或方法处理后,采用静态接触角测定仪检测其表面水、甘油接触角以及邵氏硬度变化情况,采用Owen-Wendt公式计算表面自由能γs、极性分量γsp以及非极性分量γsd变化.结果 碳离子硅橡胶经过5.25%次氯酸钠以及3%过氧化氢处理后,其表面接触角以及表面自由能发生明显变化,前者使得其表面呈现出完全的亲水性;70%酒精、2%碱性戊二醛、0.5%碘伏以及134℃高温、高压等方法对材料表面接触角以及表面自由能等影响较小.不同处理组材料表面邵氏硬度差异均无统计学意义.结论 70%酒精以及134℃高温、高压等消毒方法对碳离子硅橡胶表面性能影响最小,结合操作便利性等因素,70%酒精可认为是该材料最适宜的消毒处理方式.而次氯酸钠消毒液极不利于该材料表面形貌维持,不宜采用. 相似文献
999.
1000.