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321.
Glomerular function of neonates (25 full term and equal number of preterm neonates) at birth, on day seven and day fourteen were estimated by endogenous Creatinine clearance (CCr). The Preterm were divided into three groups viz. Group I (Gestation age (GA) 30-32 weeks), Group II (GA 33-34 weeks) and Group III (GA 35-36 weeks). Group IV consisted of 25 term neonates. Serum creatinine (in mg/dl) in all the groups of preterm ranged from 0.92 ± 0.153 to 1.204 ± 0.154 and in term neonate from 0.562 ± 0.175 to 1.148 ± 0.247 showing that the levels were inversely proportional to the period of gestation. Besides the Serum Creatinine levels in all groups of Preterm as well as term neonates were found to fall significantly (p < 0.001) during the first and second week. Glomerular filtration rate (GFR) in Group I were 16.603 ± 2.519, 19.786 ± 2.078 and 23.720 ± 2320 on day one, seven and fourteen respectively showing progressive improvement during the first two weeks. The GFRs were also found to be directly proportional to the GA. In addition the levels of GFR were found increasing significantly during the second week compared to that on day seven in all the groups of preterm neonates. GFR''s in Group I & II on all the three occasions were significantly lower (p < 0.001) than those of term counterparts, however the GFR on the first day in Group III neonates was lower than group IV, the difference was insignificant (p > 0.05). The increase in GFR in Group I on the three occasions was linear but insignificant (p > 0.05). The rise was more rapid & significant (p < 0.001) during the second week in Groups II & III. On the contrary the rate of improvement of GFR in full terms was quite rapid during the first week and gradual over the second week of life.KEY WORDS: GFR preterm & term neonates, Serum creatinine  相似文献   
322.

Background:

Femoral neck fractures are treated either by internal fixation or arthroplasty. Usually, cannulated cancellous screws are used for osteosynthesis of fracture neck of femur. The bone impregnated hip screw (BIHS) is an alternative implant, where osteosyntehsis is required in femoral neck fracture.

Materials and Methods:

The BIHS is a hollow screw with thread diameter 8.3 mm, shank diameter 6.5 mm and wall thickness 2.2 mm and holes in the shaft of the screw with diameter 2 mm, placed in a staggered fashion. Biomechanical and animal experimental studies were done. Clinical study was done in two phases: Phase 1 in a group of volunteers, only with BIHS was used in a pilot study and phase 2 comparative study was done in a group with AO cannulated screws and the other group treated with BIHS.

Results:

In the phase 1 study, out of 15 patients, only one patient had delayed union. In phase 2, there were 78 patients, 44 patients in BIHS showed early union, compared to the rest 34 cases of AO cannulated screws Out of 44 patients with BIHS, 41 patients had an excellent outcome, 2 had nonunions and one implant breakage was noted.

Conclusions:

Bone impregnated hip screw has shown to provide early solid union since it incorporates the biomechanical principles and also increases the osteogenic potential and hence, found superior to conventional cannulated cancellous screw.  相似文献   
323.
Introduction: In an attempt to further enhance the benefits of cosmesis and reduced morbidity of minimally invasive surgery, single‐port (incision) laparoscopic surgery (SPS) has emerged as a bridge between conventional laparoscopy and natural orifice transluminal endoscopic surgery. As the expertise and instrumentation required are an extension of standard laparoscopic techniques, SPS has been adapted for a variety of procedures and specialties in a short span of time. Discussion: In this article, we discuss the various SPS techniques, as well as the new devices and instrumentation available for facilitating SPS. We also review current applications reported for SPS in various surgical specialties. We present a comprehensive review of the potential benefits, limitations and risks of these novel techniques. Conclusion: Initial reports have demonstrated the technical feasibility and safety of SPS for a wide range of surgical applications. With specialized instrumentation and refinement of technique, its role will increase in coming years. Future work is necessary to improve existing instrumentation, to increase clinical experience and to assess the benefits of this surgical approach.  相似文献   
324.
目的本研究旨在以心率变异性(HRV)为手段,探讨老年人心脏自主神经活动时相的生物学特征. 方法共入选2组健康受试者观察组33例,年龄65~82岁,平均(72±10)岁;对照组31例,26~35岁,平均(30±4)岁.对2组对象进行24h动态心电图监测,记录每小时HRV的频域指标(总功率TP,低频成分LF,高频成分HF,及LF/HF).采用余弦拟合法对所得数据进行处理. 结果 HRV的频域指标呈典型的昼夜节律分布;与年轻组相比,老年人TP,LF及HF的均值及振幅明显减低;LF/HF的振幅也减低,但其均值无显著变化.2组间各指标的相位无明显变化. 结论老年人HRV的24h均值及昼夜波动振幅渐低,而其相位不变.提示该人群中心脏自主神经兴奋水平及其对心血管功能的调节能力减低.  相似文献   
325.
应用简明健康测量量表评估美沙酮维持治疗患者生活质量   总被引:1,自引:0,他引:1  
目的:对比接受与未接近美沙酮维持治疗的海洛因依赖者健康相关生活质量。方法:①选择2004-04/05在云南省个旧市美沙酮维持治疗门诊接受美沙酮维持治疗的海洛因依赖者作为治疗组(95例)。纳入标准:符合美国精神障碍诊断与统计手册第4版中海洛因依赖诊断标准;至2004-11时尚未脱失;采用滚雪球方法,于2004-11在该市社区内寻找从未接受过美沙酮维持治疗的海洛因依赖者作为对照组(37例),均符合美国精神障碍诊断与统计手册第4版中海洛因依赖诊断标准。纳入对象均对调查项目知情同意。②根据患者的日常海洛因使用量、使用方式、末次使用量决定美沙酮首次剂量,一般<40mg;导入期则根据患者的戒断症状控制情况逐渐加量。维持期的剂量差异较大,5~160mg/d,多超过60mg/d。同时根据治疗组患者的需求,每月定期开展心理干预小组活动。对照组患者未接受美沙酮维持治疗或任何戒毒措施、干预活动,评估期间时仍然在使用海洛因。③治疗组于治疗刚开始及治疗8个月后,对照组于治疗组治疗8个月后同期采用简明健康测量量表对两组对象进行健康相关生活质量评估。该量表包括躯体功能、躯体角色、肌体疼痛、总健康状况、生命力、社会功能、情绪角色及心理健康8个维度,评分越高表明生活质量越好。④计量和计数资料差异比较分别采用t检验和χ2检验。结果:治疗组95例和对照组37例均进入结果分析。参加美沙酮维持治疗8个月后,治疗组简明健康测量量表中6个维度躯体角色、总健康状况、生命力、社会功能、情绪角色及心理健康的评分分别为(6.59±1.48),(15.54±3.97),(16.20±3.91),(8.39±2.29),(4.72±1.17),(20.19±2.68)分,高于治疗刚开始时和对照组[(5.54±1.51),(13.37±3.58),(13.19±3.81),(7.17±2.21),(3.94±1.11),(17.05±4.24)分;(5.43±1.29),(11.83±3.84),(12.89±3.79),(6.71±2.12),(4.06±1.08),(15.77±4.45)分,t=3.02~7.03,P<0.01];躯体功能得分也较治疗前有了明显提高[(27.16±3.24),(26.48±3.34)分,t=1.96,P<0.05],但与对照组比较,差异不明显[(26.31±2.78)分,P>0.05]。治疗组肌体疼痛评分与治疗刚开始时和对照组相近(P>0.05)。结论:美沙酮维持治疗可有效提高海洛因依赖者的健康相关生活质量,但短期的维持治疗对肌体疼痛改善不明显。  相似文献   
326.
细胞间黏附分子与胃癌侵袭、转移关系的研究进展   总被引:1,自引:0,他引:1  
细胞间黏附分子-1(intercellularadhesionmolecule-1,ICAM-1)是体内重要的细胞活性分子,不仅参与了机体免疫过程及炎症反应,而且还通过与其相应配体的结合,介导癌细胞与不同细胞、基质的黏附,最终使癌细胞逃避免疫监视,利于侵袭转移.近年来,对ICAM-1与恶性肿瘤侵袭转移关系的研究已成为研究热点,其在肿瘤侵袭转移中的作用日益受到众多学者的重视.现就其近年的文献从ICAM-1的结构、生物学特征、在胃癌组织中的表达及作用机制等几个方面作一综述.  相似文献   
327.
Nanoparticle research is currently an area of intense scientific interest due to a wide variety of potential applications. Human beings have been exposed to airborne nanosized particles throughout their evolutionary stages, and such exposures have increased dramatically over the last century. Nanoparticle can modify the physicochemical properties of the material as well as create the opportunity for increased uptake and interaction with biological tissues through inhalation, ingestion, and injection. This combination of effects can generate adverse biological effects in living cells. Nanoparticles have proved toxic to human once in the blood stream, nanoparticles, spleen, bone marrow and nervous system can be transported around the body and be taken up by organs tissue and cell cultures, resulting in increased oxidative stress, inflammatory cytokine production and cell death. Unlike larger particles, nanoparticles may be taken up by cell mitochondria and the cell nucleus studies demonstrate the potential for nanoparticles to cause DNA mutation and induce major structural damage to mitochondria, even resulting in cell death. Size is therefore a key factor in determining the potential toxicity of a particle. How these nanoparticles behave inside the body is still a major question that needs to be resolved. There is a responsibility to test and optimize these new nanomaterials early during the development process to eliminate or ameliorate identified toxic characteristics.  相似文献   
328.
Burthem  J; Baker  PK; Hunt  JA; Cawley  JC 《Blood》1994,84(3):873-882
Integrin/extracellular-matrix interactions are central to the migration, localization, and subsequent function of lymphocytes within tissues. In hairy cell leukemia (HCL) the malignant cells display a highly characteristic tissue distribution in which interactions with extracellular matrix (ECM) are often prominent. Therefore, we used HCL as a model in which to investigate the poorly understood integrin/ECM interactions that underlie the migratory behavior of malignant B lymphocytes. Using a combined approach involving immunocytochemistry, flow cytometry, and immunoprecipitation analysis, hairy cells (HCs) were shown to have a consistent and distinctive phenotype (mainly alpha 4 beta 1, alpha 5 beta 1, alpha v beta 1, and alpha v beta 3). Furthermore, functional studies utilising adhesion assays, time-lapse video-microscopy and image analysis showed that the HCs displayed very specific adhesive behaviour in response to relevant adhesive protein ligands. HCs were able to adhere to different extents on all the adhesive proteins examined, but, on laminin and collagen, binding was weak with little cytoplasmic spreading. In contrast, the cells showed strong adhesion both to fibronectin (FN) and to vitronectin (VN). On FN, the cells spread extensively with nonpolarized cytoplasmic projections, whereas on VN cytoplasmic projections were markedly polarized. This polarized morphology was shown to reflect cell motility. Investigation of the role of individual integrin receptors in the cell movement response suggested that alpha v beta 3 is the major integrin responsible for this motile behavior. These results are discussed in relation to the limited previous data on leukemic and activated B-cell integrins, and we suggest that the HC integrins play a significant role in the characteristic behavior of HCs within tissues.  相似文献   
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