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181.
目的:探讨右美托咪定联合尼卡地平用于老年骨科手术患者控制性降压的临床疗效及其对炎症因子水平的影响。方法:选择2014年1月至2016年1月在我院行骨科手术的老年患者68例,随机分为两组,A组和B组,每组34例。A组患者接受尼卡地平控制性降压,B组患者在A组基础上静脉注射右美托咪定。比较两组患者的手术情况以及术中血流动力学指标,术中及术后血清IL-6(Interleukin-6)、TNF-α(Tumor necrosis factor-ɑ)以及CRP(C-reactive protein)的水平。结果:B组患者术中尼卡地平的使用剂量及术中出血量显著少于A组(P0.05),术后苏醒时间及拔管时间较A组显著缩短(P0.05),术中Fromme术野质量评分明显低于A组患者(P0.05)。降压后5 min,A组患者的HR显著加快(P0.05),B组患者HR相对稳定,且明显慢于A组(P0.05);两组患者的MAP以及CVP显著低于降压前(P0.05),且两组差异无统计学意义(P0.05),A组患者在降压后30 min的MAP和CVP较B组显著升高(P0.05)。两组患者术后不同时间点血清IL-6、TNF-α和CRP的水平显著上升(P0.05),其中B组患者血清IL-6、TNF-α和CRP的水平较A组明显较低(P0.05)。结论:右美托咪定联合尼卡地平用于老年患者行骨科手术时控制性降压的疗效显著,可有效降低尼卡地平的使用剂量,对患者血流动力学影响较小,并可减轻患者术后应激反应,利于患者术后恢复。  相似文献   
182.
目的:探讨基于标准病例(SP)的案例教学法(CBL)在普外科见习教学中的应用效果。方法:选取2014年6月至2015年6月我院见习的五年制临床本科医学生共112人,利用随机数字表的方法将其分为对照组和研究组,两组人数各56人。对研究组采取基于SP的CBL教学法,而对照组则使用传统临床带教方法,1个月后对理论、技能进行评价,并对学生和教师的满意进行问卷调查。结果:在技能考核和病例分析方面,研究组学生的得分显著高于对照组(P0.05),理论成绩无明显差异(P0.05)。对学生满意度的调查中,在"课堂气氛活跃"、"对学习兴趣的激发"、"利于理论与实践结合"以及"有利于形成正确临床思维"四个方面,研究组的满意度显著高于对照组(P0.05)。在对教师满意度调查中,认为试验组教学法的效率要高于对照组教学法(P0.05),而在"易实施性"满意度低于对照组教学法(P0.05),在"可操作性"方面差异无统计学意义(P0.05)。结论:与传统教学模式比较,基于SP的CBL教学法具有显著的优势,能更直观的展示某种疾病的特征,使学生通过实践巩固对基础知识的记忆,值得进一步探索并推广。  相似文献   
183.
目的:探讨不同剂量右美托嘧啶(DEX)对胸腔镜下食管癌根治术患者心肌氧供及血流动力学的影响。方法:选取66例我院拟行腔镜下食管癌根治术患者,随机分为三组,每组各22例:低剂量右美托嘧啶组(L组)(0.5μg/kg)、高剂量右美托嘧啶组(H组)(1.0μg/kg)、对照组(N组)(与L组和H组同等速率输注生理盐水),而后H组和L组均以0.5μg/kg/h维持输注DEX。记录各组输注前(T1)、输注后5 min(T2)、输注后10 min(T3)、输注后15 min(T4)、输注后30 min(T5)各组血流动力学指标:心率(HR)、收缩压(SBP)、平均动脉压(MAP)、每搏输出量(SV)、中心静脉压(CVP)、心排量(CO),计算HR与SBP的乘积RPP,抽取挠动脉和肺动脉血进行动脉血气分析,采用反向FICK法计算氧供(DO2)和氧耗(VO2)。结果:HR:H组和L组患者HR随时间的推移呈下降趋势,H组T3、T4、T5时间点HR较T1时间点显著降低(P0.05);与N组相比,H组和L组T3、T4、T5时间点HR显著降低(P0.05)。MAP:H组T3、T4、T5时间点MAP显著低于L组(P0.05);H组T3、T4时间点MAP显著低于N组(P0.05);H组T5时间点MAP显著低于同组T1、T2时间点(P0.05)。SBP:H组T3、T4、T5时间点SBP与L组和N组比较显著降低(P0.05);H组T5时间点SBP较同组T1、T2时间点显著降低(P0.05)。RPP:H组T3、T4、T5时间点RPP与同组T1、T2时间点和N组比较显著降低(P0.05)。DO2:H组T5时间点DO2与L组和N组比较显著降低(P0.05)。VO2:L组患者VO2T3、T4、T5时间点与组内T1、T2时间点和N组相比显著降低(P0.05);H组VO2T3、T4、T5时间点与组内T1、T2时间点和N组相比显著降低(P0.05)。结论:小剂量(0.5μg/kg)输注DEX能降低胸腔镜下食管癌患者心肌氧耗,维持血流动力学稳定,高剂量(1.0μg/kg)输注DEX降低心肌氧耗的同时会降低心肌氧供,存在一定风险,对于患有冠心病以及心肺功能低下的老年患者,建议给予小剂量输注DEX,并监测血流动力学指标,及时调整DEX用量。  相似文献   
184.
Stereotactic biopsy is used to enable diagnostic confirmation of brain tumors and treatment planning. Despite being a well‐established technique, it is related to significant morbidity and mortality rates mostly caused by hemorrhages due to blood vessel ruptures. This paper presents a method of vessel detection during stereotactic biopsy that can be easily implemented by integrating two side‐view fibers into a conventional side‐cutting biopsy needle. Tissue within the needle window is illuminated through the first fiber; the second fiber detects the remitted light. By taking the ratio of the intensities at two wavelengths with strongly differing hemoglobin absorption, blood vessels can be recognized immediately before biopsy sampling. Via ray tracing simulations and phantom experiments, the dependency of the remission ratio R = I578/I650 on various parameters (blood oxygenation, fiber‐to‐vessel and inter‐fiber distance, vessel diameter and orientation) was investigated for a bare‐fiber probe. Up to 800–1200 µm away from the probe, a vessel can be recognized by a considerable reduction of the remission ratio from the background level. The technique was also successfully tested with a real biopsy needle probe on both optical phantoms and ex‐vivo porcine brain tissue, thus showing potential to improve the safety of stereotactic biopsy.

Dual‐wavelength remission measurement for the detection of blood vessels during stereotactic biopsy.  相似文献   

185.
The use of skin flaps in reconstructive surgery is the first-line surgical treatment for the reconstruction of skin defects and is essentially considered the starting point of plastic surgery. Despite their excellent usability, their application includes general surgical risks or possible complications, the primary and most common is necrosis of the flap. To improve flap survival, researchers have used different methods, including the use of adiposederived stem cells, with significant positive results. In our research we will report the use of adipose-derived stem cells in pedicle skin flap survival based on current literature on various experimental models in animals.  相似文献   
186.
Most organisms live in changing environments or do not use the same resources at different stages of their lives or in different seasons. As a result, density dependence will affect populations differently at different times. Such sequential density dependence generates markedly different population responses compared to the unrealistic assumption that all events occur simultaneously. Various field studies have also shown that the conditions that individuals experience during one period can influence success and per capita vital rates during the following period. These carry-over effects further complicate any general principles and increase the diversity of possible population dynamics. In this review, we describe how studies of sequential density dependence have diverged in directions that are both taxon-specific and have non-overlapping terminology, despite very similar underlying problems. By exploring and highlighting these similarities, we aim to improve communication between fields, clarify common misunderstandings, and provide a framework for improving conservation and management practices, including sustainable harvesting theory.  相似文献   
187.
Regeneration in medicine is a concept that has roots dating back to the earliest known records of medical interventions. Unfortunately, its elusive promise has still yet to become a reality. In the field of plastic surgery, we use the common tools of the surgeon grounded in basic operative principles to achieve the present day equivalent of regenerative medicine. These reconstructive efforts involve a broad range of clinical deformities, both congenital and acquired. Outlined in this review are comments on clinical conditions and the current limitations to reconstruct these clinical entities in the effort to practice regenerative medicine. Cleft lip, microtia, breast reconstruction, and burn reconstruction have been selected as examples to demonstrate the incredible spectrum and diverse challenges that plastic surgeons attempt to reconstruct. However, on a molecular level, these vastly different clinical scenarios can be unified with basic understanding of development, alloplastic integration, wound healing, cell–cell, and cell‐matrix interactions. The themes of current and future molecular efforts involve coalescing approaches to recapitulate normal development in clinical scenarios when reconstruction is needed. It will be a better understanding of stem cells, scaffolding, and signaling with extracellular matrix interactions that will make this future possible. Eventually, reconstructive challenge will utilize more than the current instruments of surgical steel but engage complex interventions at the molecular level to sculpt true regeneration. Immense amounts of research are still needed but there is promise in the exploding fields of tissue engineering and stem cell biology that hint at great opportunities to improve the lives of our patients. Birth Defects Research (Part C) 84:322–334, 2008. © 2008 Wiley‐Liss, Inc.  相似文献   
188.
This paper is to illustrate the infestation and related ecological characteristics of chigger mites on the Asian house rat (Rattus tanezumi). A total of 17,221 chigger mites were collected from 2,761 R. tanezumi rats, and then identified as 131 species and 19 genera in 2 families. Leptotrombidium deliense, the most powerful vector of scrub typhus in China, was the first major dominant species on R. tanezumi. All the dominant mite species were of an aggregated distribution among different individuals of R. tanezumi. The species composition and infestations of chiggers on R. tanezumi varied along different geographical regions, habitats and altitudes. The species-abundance distribution of the chigger mite community was successfully fitted and the theoretical curve equation was Ŝ (R)=37e−(0.28R. The total chigger species on R. tanezumi were estimated to be 199 species or 234 species, and this further suggested that R. tanezumi has a great potential to harbor abundant species of chigger mites. The results of the species-plot relationship indicated that the chigger mite community on R. tanezumi in Yunnan was an uneven community with very high heterogeneity. Wide geographical regions with large host samples are recommended in the investigations of chigger mites.  相似文献   
189.
This study was undertaken to determine which rodent species serve as primary reservoirs for the Lyme disease spirochete Borrelia burgdorferi in commonly occurring woodland types in inland areas of northwestern California, and to examine whether chaparral or grassland serve as source habitats for dispersal of B. burgdorferi‐ or B. bissettii‐infected rodents into adjacent woodlands. The western gray squirrel (Sciurus griseus) was commonly infected with B. burgdorferi in oak woodlands, whereas examination of 30 dusky‐footed woodrats (Neotoma fuscipes) and 280 Peromyscus spp. mice from 13 widely‐spaced Mendocino County woodlands during 2002 and 2003 yielded only one infected woodrat and one infected deer mouse (P. maniculatus). These data suggest that western gray squirrels account for the majority of production by rodents of fed Ixodes pacificus larvae infected with B. burgdorferi in the woodlands sampled. Infections with B. burgdorferi also were rare in woodrats (0/47, 0/3) and mice (3/66, 1/6) captured in chaparral and grassland, respectively, and therefore these habitats are unlikely sources for dispersal of this spirochete into adjacent woodlands. On the other hand, B. bissettii was commonly detected in both woodrats (22/47) and mice (15/66) in chaparral. We conclude that the data from this and previous studies in northwestern California are suggestive of a pattern where inland oak‐woodland habitats harbor a B. burgdorferi transmission cycle driven primarily by I. pacificus and western gray squirrels, whereas chaparral habitats contain a B. bissettii transmission cycle perpetuated largely by I. spinipalpis, woodrats, and Peromyscus mice. The dominant role of western gray squirrels as reservoirs of B. burgdorferi in certain woodlands offers intriguing opportunities for preventing Lyme disease by targeting these animals by means of either host‐targeted acaricides or oral vaccination against B. burgdorferi.  相似文献   
190.
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