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141.
目的:编制灾害护理知信行量表,并对其进行信效度检验。方法:根据知信行理论模型编制灾害护理知信行量表。随机抽取500名护生实施问卷调查并进行因子分析及信效度评估,3周后,随机抽取200名护生检验重测信度。结果:灾害护理知信行量表包括知识、态度及行为3个维度,共30个条目,总量表及各维度Cronbach′sα系数分别为0.96,0.92,0.95,0.96;分半信度为0.82,总量表及各维度重测信度分别为0.90,0.82,0.83,0.85。量表总内容效度指数为0.93,各条目内容效度指数为0.85~1.00。结论:灾害护理知信行量表具有良好的信效度,可作为评估护生灾害护理知信行水平的工具,可作为灾害护理教育的形成性评价指标。  相似文献   
142.
目的探讨人工股骨头置换术治疗老年股骨转子间不稳定性骨折的近期疗效。方法应用人工股骨头置换术治疗高龄、有明显骨质疏松的股骨转子间不稳定性骨折患者20例。结果20例获2-24个月随访,患者术后14-35d负重行走,无坠积性肺炎、尿路感染的发生。术后X线片示假体位置良好,无下沉松动,无脱位,未出现髋内翻。Harris评分为75-92分。1例行走髋关节疼痛,1例9个月时X线片发现髋臼磨损。结论该手术方法具有功能恢复好、并发症少、能早期负重等优点,有临床上推广应用的价值,但应严格掌握其适应证。  相似文献   
143.
患者男,61岁,因头枕部丘疹3年就诊。患者于3年前无明显诱因下发现枕部丘疹,无自觉症状,后缓慢增大。否认病程中出血、溃疡、脱屑等。体检:一般情况好,各系统检查未见异常。皮肤科检查:枕部见一枚黄豆大小丘疹,直径约9 mm,淡红色,境界清晰,表面光滑,质地坚实(图1A)……  相似文献   
144.
烟酰胺是烟酸的吡啶-3-羧酸酰胺,局部外用耐受性好,具有减少色素沉着、增加皮肤屏障功能、防止光损伤和光致癌、保持皮肤能量平衡和新陈代谢及辅助治疗多种皮肤病等功效。  相似文献   
145.
BackgroundAccumulating data suggest antiviral effects of povidone-iodine against the Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. This narrative review aims to examine the antiviral mechanisms of povidone-iodine, efficacy of povidone-iodine against the SARS-CoV-2 virus, and safety of povidone-iodine to human epithelial cells and thyroid function.MethodsWe searched the electronic databases PubMed, Embase, Cochrane Library, ClinicalTrials.gov and World Health Organization’s International Clinical Trials Registry Platform for articles containing the keywords “povidone-iodine”, “SARS-CoV-2” and “COVID-19” from database inception till 3 June 2021.ResultsDespite in vitro data supporting the anti-SARS-CoV-2 effects of povidone-iodine, findings from clinical studies revealed differences in treatment response depending on study settings (healthy vs. hospitalized individuals), treatment target (nasal vs. oral vs. pharynx), method of administration (oral rinse vs. gargle vs. throat spray) and choice of samples used to measure study endpoints (nasopharyngeal vs. saliva). One large-scale clinical trial demonstrated reduction in the incidence of SARS-CoV-2 infection among participants who administered povidone-iodine 3 times daily during an active outbreak. Povidone-iodine is also used to disinfect the oro-pharyngeal space prior to dental or otolaryngology procedures. Although existing data suggest minimal impact of povidone-iodine on thyroid function, high-quality safety data are presently lacking.ConclusionsPovidone-iodine application to the oropharyngeal space could complement existing non-pharmacological interventions to reduce SARS-CoV-2 infection especially in high exposure settings.

Key messages

  • Accumulating data suggest antiviral effects of povidone-iodine against the SARS-CoV-2 virus.
  • Findings from clinical studies reveal differences in treatment response depending on study settings, treatment target, method of administration and choice of samples used to measure study endpoints. One large-scale clinical trial observed reduction in the incidence of SARS-CoV-2 infection among participants who administered povidone-iodine 3 times daily during an active outbreak.
  • Povidone-iodine application to the oropharyngeal space could complement existing non-pharmacological interventions to reduce SARS-CoV-2 infection especially in high exposure settings.
  相似文献   
146.
目的:探讨外源性人低氧诱导因子(HIF)-1α基因在成纤维细胞中的表达及对体外培养人毛囊的影响。方法:通过脂质体将含有HIF—1α cDNA的真核表达载体pcDNA3.0瞬时转染成纤维细胞,应用反转录(RT)-PCR、免疫组化等方法检测HIF-1α在成纤维细胞中的表达。同时通过ELISA检测转染细胞上清液中血管内皮生长因子(VEGF)的表达情况。进一步将该上清加至体外培养的人毛囊和细胞中,显微镜下测量毛囊的平均生长长度,并观察毛囊的形态学变化。并通过四甲基偶氮唑蓝(MTT)法检测加入转染上清的细胞活性。结果:成功地将HIF—1α真核表达载体HIF—1α pcDNA3.0瞬时转染了成纤维细胞,用RT-PCR、免疫组化染色可检测出细胞中HIF—1α的表达,MTT检测转染后细胞活性增强,并且该上清液可以检测出VEGF的表达。该上清可以明显促进体外培养的人毛囊生长.延缓其进入退行期。结论:应用脂质体能够成功地将外源性人HIF—1α基因转染成纤维细胞,并进行有效表达,其表达的HIF—1α可增强细胞活性,且可诱导转染细胞上清液中VEGF的表达,在体外具有促进人毛囊生长的生物学活性。  相似文献   
147.
阅读疗法改善大学生心理障碍的研究   总被引:2,自引:0,他引:2  
目的观察用阅读疗法改善大学生心理障碍的效果。方法用大学生人格调查表(UPI)对在校大学生进行调查,找出需要关注的学生40人,随机分成实验组和对照组。对实验组进行为期1年的阅读辅导,阅读辅导前后用scl-90测查,观察两组的效果。结果实验组辅导前后10项因子中有8项有明显改善(P<0.05或0.01);对照组第2次各因子与第1次相比差异无统计学意义(P>0.05);实验组与对照组第2次测查结果比较,有4项统计有意义(P<0.05),分别是:强迫症状、抑郁、偏执、精神病性因子项。结论阅读疗法对改善大学生心理障碍有效。  相似文献   
148.
There is a lack of studies on the association between whole grain intake and cardiometabolic risk factors in China and the current definition of whole grains is inconsistent. This study defined whole grains in two ways, Western versus traditional, and examined their associations with the risks of major cardiometabolic factors (CMFs) among 4706 Chinese adults aged ≥18 years, who participated in surveys both in 2011 and in 2015. Diet data were collected by consecutive 3 d 24 h recalls, together with household seasoning weighing. Whole grains were defined as grains with a ratio of fiber to carbohydrate of ≥0.1, while coarse grains were defined as grains except for rice and its products, and wheat and its products. Multivariable logistic regressions were modeled to analyze the associations of intakes of whole grains and coarse grains, respectively, with risks of major CMFs including obesity-, blood pressure-, blood glucose- and lipid-related factors, which were defined by International Diabetes Federation and AHA/NHLBI criteria. After adjusting for potential confounders, the odds of elevated LDL-C decreased with the increasing intake levels of whole grains (OR 0.64, 95% CI 0.46–0.88, p-trend < 0.05). Moreover, adults with the whole grain intake of 50.00 to 150.00 g/day had 27% lower odds of overweight and obesity (OR 0.73, 95% CI 0.54–0.99) and 31% lower odds of elevated LDL-C (OR 0.69, 95% CI 0.49–0.96), as compared with non-consumers. In conclusion, given the significant nutrient profiles of whole grains and coarse grains, the adults with higher intakes of whole grains only may have a lower risk of LDL-C and overweight and obesity.  相似文献   
149.
岳媛  樊旭 《中医康复》2024,15(8):33-36
腰椎间盘突出症(Lumbar Disc Herniation, LDH)是常见的慢性退行性疾病,与年龄、职业、外伤、环境等因素有关,患者症状多见腰痛、一侧或双下肢放射痛、间歇性跛行。目前腰椎间盘突出症仍多采用保守治疗,合谷刺法具有解痉止痛、激发经气的作用,在治疗腰椎间盘突出症上应用广泛。本文从腰椎间盘突出症的病因病机、合谷刺法理论基础、应用合谷刺治疗腰椎间盘突出症的临床进展3个方面对相关文献进行梳理,阐述合谷刺法与腰椎间盘突出症的相关性,为腰椎间盘突出症的针刺治疗提供新的切入点,以期为腰椎间盘突出症的临床治疗提供思路。  相似文献   
150.
A series of cinchona alkaloid-based NNP ligands, including a new one, have been employed for the asymmetric hydrogenation of ketones. By combining ruthenium complexes, various aromatic and heteroaromatic ketones were smoothly reacted, yielding valuable chiral alcohols with extremely high 99.9% ee. Moreover, a proposed reaction mechanism was discussed and verified by NMR.

A series of cinchona alkaloid-based NNP ligands including a new one has been employed for the asymmetric hydrogenation of ketones. By combining ruthenium complexes, various ketones were smoothly reacted with up to 99.9% ee.

Since the well-known failure of using racemic thalidomide, attention has been paid to the manufacture of optically pure compounds as effective components in pharmaceuticals and agrochemicals. Asymmetric hydrogenation of ketones, especially heteroaromatic ketones, has emerged as a popular facile route to approach enantiopure secondary alcohols as essential intermediates for the construction of biologically active molecules.1–4 Knowles et al.5 pioneered the production of enantioenriched chiral compounds in 1968, and Noyori and co-workers6–8 laid the cornerstone of asymmetric hydrogenation in 1990s. Subsequently, numerous catalytic systems have been developed. Ru-BICP-chiral diamine-KOH was developed and proved to be effective for asymmetric hydrogenation of aromatic ketones by Xumu Zhang.9 Cheng-yi Chen reported asymmetric hydrogenation of ketone using trans-RuCl2[(R)-xylbinap][(R)-daipen] and afforded secondary alcohol in 92–99% ee.10 Mark J. Burk and Antonio Zanotti-Gerosa disclosed Phanephos-ruthenium-diamine complexes catalyzing the asymmetric hydrogenation of aromatic and heteroaromatic ketones with high activity and excellent enantioselectivity.11 Qi-Lin Zhou et al. designed and synthesized chiral spiro diphosphines as a new chiral scaffold applied in the asymmetric hydrogenation of simple ketones with extremely high activity and up to 99.5% ee.12–15 Similarly, Kitamura and co-workers have developed a set of tridentate binan-Py-PPh2 ligands for the asymmetric hydrogenation of ketones affording excellent results.16 Recently, chiral diphosphines and tridentate ligands based on ferrocene have been developed for the asymmetric hydrogenation of carbonyl compound with a remarkable degree of success.17–21 Despite many ligands for asymmetric hydrogenation of ketones have been reported, expensive reagent and multistep complicated reactions were employed to synthesize most of them.22–24 In light of increasing industrial demand, easily obtained, cheap and practical chiral ligands are still highly desirable. In addition to chiral ligands, the selection of metals was essential for asymmetric hydrogenation.25–27 Although Mn,28–30 Fe,31–34 Co,35–37 Ni38,39 and Cu40,41 metals were proved to be effective for asymmetric hydrogenation in recent years, Rh,42–44 Ir45,46 and especially Ru remained the most preferred metals. Ruthenium47–51 was chosen owing to its superior performances in terms of low price, selectivity and activity. Takeshi Ohkuma,52 Hanmin Huang53,54 and Johannes G. de Vries55 all successfully used ruthenium catalysts for asymmetric hydrogenation of ketones. Admittedly, there is a continuing interest in the development of cheaper, simpler and more efficient catalysts for the asymmetric hydrogenation of ketones under mild conditions to access corresponding secondary alcohols. Recently, we developed new NNP chiral ligands derived from cinchona alkaloid for the asymmetric hydrogenation of various ketones in extremely excellent results using a iridium catalytic system.56 Prompted by these encouraging results, we were interested in exploring a ruthenium-catalyzed asymmetric hydrogenation of ketones with NNP chiral ligands derived from cinchona alkaloid. Here, we showed that changing from iridium to ruthenium, with the same simple synthetic ligands, delivered a catalyst catalyzed asymmetric hydrogenation of ketones to give the industrially important chiral alcohols with up to 99.9% ee. Although the catalytic activity of ruthenium catalyst was not as high as that of the iridium catalyst, the enantioselectivity could be maintained, and even showed higher enantioselectivity in the hydrogenation of some substrates.Chiral tridentate ligand NNP (L1–L10) were synthesized and characterized as reported in our previous publication. With tridentate ligands in hand, we began to evaluate the catalytic performance in benzylidene-bis(tricyclohexylphosphine) dichlororuthenium-catalyzed asymmetric hydrogenation of acetophenone employed as a standard substrate (Fig. 2). MeOH was found to be a better one as the conversion and enantioselectivity were 99.9% and 98.2%, respectively. Bases screening showed that Ba(OH)2 was superior to the others, giving >99.9% conversion and 98.8% ee in the present catalytic system (Fig. 1). Ligand screening revealed that the configuration of chiral centers of cinchona alkaloids of the ligand markedly affected the catalytic performance. NNP ligands derived from cinchonine and quinidine appeared to benefit both the reaction rate and enantioselectivity, while those derived from cinchonidine and quinine had the opposite effect. Further, different NNP ligands that bearing different substituents on the phenyl rings were evaluated. Similar to our previous research, ligands with electron-withdonating substituents showed better catalytic performance than those with electron-withdrawing substituents. However, it was noted that the more electron-withdonating substituents furnished lower activity but same enantioselectivity. The optimal ligand L5 derived from quinidine with one methoxy group on benzene ring provided the corresponding chiral alcohol with 99.9% conversion and 98.8% ee. Considering that L3 derived from cinchonine had similar catalytic performance to L4 derived from quinidine, new ligand L10 similar to L5 with one methoxy group on benzene ring was synthesized and applied to the asymmetric hydrogenation of template substrate. 99.6% conversion and 97.6% ee was obtained. Hence, L5 was employed as better ligand in subsequent experiments.Open in a separate windowFig. 1The effect of different bases for the asymmetric hydrogenation of acetophenone (substrate/Ru/L5 = 500/1/2, ketones: 0.429 mol L−1, base: 0.15 mol L−1, MeOH: 2 mL, 30 °C, 6 MPa, 2 h.).Open in a separate windowFig. 2The effect of different solvents for the asymmetric hydrogenation of acetophenone. (substrate/Ru/L5 = 1000/1/2, ketones: 0.858 mol L−1, Ba(OH)2: 0.15 mol L−1, solvent: 2 mL, 30 °C, 6 MPa, 2 h.).The effect of different ligand for the asymmetric hydrogenation of acetophenonea
EntryLigandsCon./%ee/%Config
1L147.578.2 R
2L256.177.8 R
3L3>9994.0 S
4L480.897.0 S
5L5>9998.8 S
6L654.298.0 S
7L72.184.2 S
8L891.198.0 S
9L936.592.8 S
10L10>9997.6 S
Open in a separate windowaSubstrate/Ru/L = 2000/1/2, ketones: 1.715 mol L−1, Ba(OH)2: 0.15 mol L−1, MeOH: 2 mL, 30 °C, 6 MPa, 2 h.In order to evaluate the general applicability of this method, we have surveyed the substrate scope. As can be discerned from the data in Fig. 3, most of aryl alkyl ketones P1–P21 were hydrogenated with very high enantioselectivities (97.1–99.9% ee). Under the conditions employed, the electron effect and steric hindrance seemed to have no significant impact on the enantioselectivities of asymmetric hydrogenation. However, the activities were slightly affected by steric hindrance, especially ortho-substituted group. Significantly, Ru/L5 showed high enantioselectivity 98.2% in the hydrogenation of [3,5-bis(trifluoromethyl)phenyl]ethanone and its corresponding enantiopure alcohol P21 was key chiral intermediates for the NK-1 receptor antagonist aprepitant.57,58 Additionally, chiral heteroaromatic alcohols containing nitrogen, oxygen or sulfur in the heterocyclic ring were considerable organic synthetic intermediate in pharmaceuticals and organic synthesis.59–61 Nevertheless, due to the coordination ability of the heteroaromatic moiety, the asymmetric hydrogenation of heteroaromatic ketones has been less investigated. Surprisingly, the protocol was found to be very effective for asymmetric hydrogenation of various heteroaromatic ketones P22–P35. The substrates were all well reduced smoothly to afford the corresponding chiral alcohol with 97.1–99.9% ee. Notably, meta- and para-acetyl pyridines, generally as a challenging hydrogenation substrates62–64 owe to stronger coordination ability, were also hydrogenated with up to 97.2% ee (P33 and P34). Gratifyingly, 97.4 ee was obtained when acetonaphthone employed (P36). Benzo-fused seven-membered cyclic ketone proceeded well to afford the corresponding chiral alcohols with 99.6% ee (P37). To further explore substrate scope, we checked the effectiveness of method for asymmetric hydrogenation of unsaturated ketones. Although, both substrates were hydrogenated with high yield, only medium enantioselectivity 73.8 and 78.3% ee were given, respectively.Open in a separate windowFig. 3Asymmetric hydrogenation of ketones catalyzed by Ru/L5. (Substrate/Ru/L5 = 200/1/2, ketones: 0.171 mol L−1, Ba(OH)2: 0.15 mol L−1, MeOH: 2 mL, 30 °C, 6 MPa, 2 h, isolated yield, ee was determined by GC or HPLC on chiral stationary phase (see the ESI); asubstrate/Ru/L5 = 2000/1/2; bsubstrate/Ru/L5 = 100/1/2, 25 °C; csubstrate/Ru/L5 = 50/1/2, 25 °C, 24 h; dsubstrate/Ru/L5 = 25 °C; esubstrate/Ru/L5 = 50/1/2, 4 h; fEtOH).To understand the mechanism of the reaction, NMR was introduced to investigated active species. Single peak at δ = 19.91 ppm belonging to phenyl vinyl group of the complex disappeared in the 1H NMR spectrum when the complex was mixed with the ligand (Fig. S1, ESI). In the meantime, 31P NMR spectrum of the mixture exhibited new singlet at δ = 55.71 ppm (s) with the signal of complex disappearing (Fig. S2, ESI). These maybe indicated the formation of ruthenium complex A. Subsequently, a new weak signal was generated in the 31P NMR spectrum with the introduction of hydrogen and base (Fig. S3, ESI). These may indicate the formation of ruthenium hydride complexes. Meanwhile, the 1H NMR spectrum exhibited several weak signals below 0 ppm (Fig. S4, ESI). These data also verified the formation of ruthenium hydride complexes. Reference to relevant literature,65–67 the proposed catalytic cycle for the asymmetric hydrogenation of ketones with the ruthenium complex was shown in Scheme 1. First, the ruthenium complex reacted with ligands to form complex A. In the presence of base and hydrogen, the complex A lost two chlorine atoms to transform into dihydride complex B. Then, a hydridic Ru–H and a protic N–H unit were transferred from dihydride B to the carbonyl group of the ketones through the transition state TS to produce chiral alcohol. And the ruthenium complex lost two hydrogen atoms to form complex C. Finally, dihydride B was regenerated in hydrogen atmosphere. Compared with the reported iridium catalytic system with the same chiral ligands, the hydrogenation activity of the ruthenium catalytic system decreased significantly although maintained high enantioselectivity. The result indicates that the selection of metals was as important as chiral ligands for asymmetric hydrogenation.Open in a separate windowScheme 1Proposed mechanism for the asymmetric hydrogenation.  相似文献   
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