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991.
目的:探讨MR诊断颈动脉体瘤(CBT)的价值。材料与方法:4例经手术病理证实的CBT进行MRI和MRA检查。结果:4例CBT MR检查均显示颈总动脉分叉(common cartid artery bifurcation,CCAB)处类圆形或椭圆形肿瘤,包绕颈内、外动脉,T_1WI呈等或略高信号,T_2WI呈高信号;包膜完整。T_1WI、T_2WI均呈低信号。肿瘤中见多发蜿蜓纡曲的肿瘤小血管。MRA均示CCAB角杯状扩大及肿瘤血管丛。结论:MR不仅能直接显示肿瘤部位、形态、大小及颈动脉关系,也能显示肿瘤血管及CCAB角扩大,是CBT诊断与鉴别的理想方法。 相似文献
992.
早产儿、低出生体重儿喂养方式与体重增长关系的探讨 总被引:17,自引:0,他引:17
目的探讨早产儿、低出生体重儿喂养方式与体重增长关系。方法选择 98例早产儿 ,分成三组 ,一组采用静脉内营养 ,其余两组在消化道喂养同等条件下 ,对其中一组采取头高脚低 (成 2 0°角 )斜坡位。结果观察组与对照组比较体重增长有明显差异 (P <0 .0 5) ;消化道喂养组与静脉内营养组比较体重增长无明显差异 (P >0 .0 5)。结论通过对早产儿及低出生体重儿喂养方式的改进 ,配合全面的综合护理 ,可防止生理性体重下降和维持正常体重的增长。 相似文献
993.
目的:研究小腿截肢患者站立状态下假肢对线对下肢受力特性的影响.方法:以假肢侧承重线和重力线作为评价指标,改变假肢矢状面和额状面的对线,采用激光测力平台测量患者静态站立时残侧承重线和重力线的位置,研究下肢受力状况的变化.结果:假肢侧承重线受踝关节对线的影响大于腿管对线调节的影响,并且力线随腿管与接受腔的前倾而前移,而额状面对线的影响很小;矢状面内重力线主要受踝关节对线调节的影响,并且与变化角近似正比例相关.结论:矢状面假肢对线调整对残侧下肢受力状况的影响较大,而额状面的对线调整影响较小. 相似文献
994.
目的 探讨妊娠期糖耐量异常对胎儿体质量及新生儿并发症发生率的影响.方法 对2502例孕妇进行口服50 g葡萄糖筛查试验(GCT),对156例异常者再行75 g葡萄糖耐量试验(OGTT),确诊妊娠期糖尿病(GDM) 86例,妊娠糖耐量受损(GIGT) 70例,与对照组300例比较,分别比较胎儿出生体质量、新生儿并发症的发生率.结果 GIGT及GDM组的胎儿体质量大于胎龄儿及巨大儿出生率明显高于对照组、适于胎龄儿出生率明显低于对照组,差别有统计学意义(P<0.01);小于胎龄儿出生率亦高于对照组(P<0.05);GIGT及GDM组孕妇所生新生儿在低血糖、高胆红素血症及产伤发病率明显高于对照组,差异有统计学意义(P<0.01);并发早产、窒息的发病率高于对照组,差异有统计学意义(P<0.05).结论 在临床中非常有必要对所有孕妇进行系统、正规的糖代谢异常检测及确诊后应规范治疗、监测;对所有糖代谢异常孕妇分娩的新生儿及时监测血糖、关注并发症的的发生,及时给予干预. 相似文献
995.
Cadmium (Cd) is an environmental contaminant showing a variety of deleterious effects, including the potential threat for the ecological environment and human health via food chains. Low molecular weight chitosan (LMWC) has been demonstrated to be an effective antioxidant. Metallothionein (MT) mRNA levels and activities of glutathione‐S‐transferase (GST), superoxide dismutase (SOD), acid phosphatase (ACP), Na+,K+‐ATPase, and Ca2+‐ATPase as well as malondialdehyde (MDA) contents in the gills of the freshwater crab Sinopotamon yangtsekiense were analyzed in vivo in order to determine the injury of Cd exposure on the gill tissues as well as the protective effect of LMWC against this injury. The results showed that there was an apparent accumulation of Cd in the gills, which was lessened by the presence of LMWC. Moreover, Cd2+ significantly increased the gill MT mRNA levels, ACP activity and MDA content while decreasing the activities of SOD, GST, Na+,K+‐ATPase, and Ca2+‐ATPase in the crabs relative to the control. Cotreatment with LMWC reduced the levels of MT mRNA and ACP but raised the activities of GST, Na+,K+‐ATPase, and Ca2+‐ATPase in gill tissues compared with the crabs exposed to Cd2+ alone. These results suggest that LMWC may exert its protective effect through chelating Cd2+ to form LMWC‐Cd2+ complex, elevating the antioxidative activities of GST, Na+,K+‐ATPase, and Ca2+‐ATPase as well as alleviating the stress pressure on MT and ACP, consequently protecting the cell from the adverse effects of Cd. © 2012 Wiley Periodicals, Inc. Environ Toxicol 29: 298–309, 2014. 相似文献
996.
Santina Battaglia Paola Taddei Silvia Tozzi Alessandra Sudanese Saverio Affatato 《International orthopaedics》2014,38(6):1183-1190
Purpose
The research questions of the present study were: (1) Is total knee prosthesis wear behaviour influenced by implant size, body weight and their combined effect? (2) Are these findings significant and helpful from a clinical point of view?Methods
Two very different sizes of the same total knee prosthesis (TKP), previously tested with ISO 14243 parameters, were tested on a knee simulator for a further two million cycles using a modified ISO 14243 load waveform. Roughness examination was performed on the metallic components. Gravimetric and micro-Raman spectroscopic analyses were carried out on the polyethylene inserts.Results
The average volumetric mass loss was 69 ± 3 mm3 and 88 ± 4 mm3 for smaller and bigger size, respectively. Bigger TKPs are little influenced by an increased load, while the wear trend of the smaller TKP showed a redoubled slope, and more significant morphology changes were observed. However, the two sizes seem to behave similarly when subjected to a load increase of 15 %; the slope of the volumetric mass loss trend was comparable for the two sets of inserts, which did not appear significantly different also at the molecular level. Roughness average parameters of the lateral femoral condyle support this evidence.Conclusions
It can be asserted that the body weight and implant size are relevant to the understanding of TKP wear behaviour. A post-implantation body weight increase in a patient with smaller knee dimensions could results in more critical effects on prosthesis long-term performance. 相似文献997.
A prospective study was performed in the Reproduction Center of Ichikawa General Hospital (Chiba, Japan) to assess the relationship between dyslipidaemia and sperm quality and serum hormone levels in male patients in Japan. The semen parameters and blood samples were assessed in relation to several variables, including body mass index (BMI) and serum triglyceride (TG) levels. Between 2011 and 2012, 167 male partners of infertile couples aged 22–46 years (mean: 36.5 years) were referred to the reproduction centre. In total, 66 patients (39.5%) had hypertriglyceridaemia (TG level ≥ 150 mg dl?1). There was no significant relationship between serum TG levels and sperm concentration or motility; however, the serum TG level was positively associated with the sperm morphological traits. Furthermore, the serum levels of glutamic oxaloacetic transaminase and glutamic pyruvic transaminase were associated with the serum TG levels. By contrast, a negative relationship between serum testosterone and TG levels was discovered. 相似文献
998.
K. Pummer R. Zigeuner S. Brookman‐May W. F. Wieland H. M. Fritsche A. Aziz 《Andrologia》2014,46(2):106-111
The influence of overweight and obesity on sperm quality and reproductive hormone levels is under discussion. The aim of the present retrospective study was to evaluate the influence of body mass index (BMI) on sperm quality and reproductive hormones. We analysed semen samples and serum levels of FSH, LH, T and PRL of a total of 2110 men attending our andrology unit from 1994 to 2010 due to infertility work‐up. Patients were stratified according to their BMI in four groups. Main outcome measures were sperm motility, morphology and concentration. Serum levels of FSH, LH, T and PRL were evaluated as well. No statistically significant difference was found for sperm quality and BMI between patients categorised according to the four BMI levels. T (P < 0.001) and LH (P = 0.006) significantly differed between the four groups. In multivariable analysis, BMI did not have significantly independent influence on all assessed sperm quality parameters, whereas BMI significantly influenced hormone values for LH (P = 0.001), T (P = <0.001) and PRL (P = 0.044). We therefore conclude that BMI has no significant impact on sperm quality parameters. However, serum levels of LH, T and PRL were significantly influenced by BMI. 相似文献
999.
Eiichi Sato Takashi Ando Jiro Ichikawa Genki Okita Nobutaka Sato Masanori Wako Tetsuro Ohba Satoshi Ochiai Tetsuo Hagino Richard Jacobson Hirotaka Haro 《Journal of orthopaedic research》2014,32(12):1619-1627
Osteoarthritis (OA) is a group of common, chronic, and painful inflammatory joint diseases. One important finding in OA patients is a remarkable decrease in the molecular weight of hyaluronic acid (HA) in the synovial fluid of affected joints. Therapeutic HA is available to patients in most parts of the world as a viscosupplementation product for the treatment of OA. Previous clinical reports show that high molecular weight HA (HMWHA) more effectively relieves pain than low molecular weight HA (LMWHA). However, the mechanism behind this finding remains unclear. In this study, we investigated whether a LMWHA (Low‐0.9 MDa) and two types of HMWHA (High‐1.9 MDa and 6 MDa) differentially affected chondroregulatory action. We tested this using ATDC5 cell, a murine chondrocytic cell line widely used in culture systems to study chondrogenic differentiation. We found that HMWHA, especially hylan G‐F 20 (High‐6 MDa), significantly induced aggrecan and proteoglycan accumulation, nodule formation, and mRNA expression of chondrogenic differentiation markers in a time‐ and dose‐dependent manner. In addition, we showed that HMWHA prevented TNF‐α induced inhibition of chondrogenic differentiation, with no effect on cell proliferation or viability. These results reveal that HMWHA significantly promotes chondrogenic differentiation of ATDC5 cells in vitro, and suggest that HMWHA plays a significant chondroregulatory role in vivo. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:1619–1627, 2014. 相似文献
1000.
Emmanuel Gibon Antoine MoutonDorick Passeron MD Vincent Le StratWilfrid Graff MD Simon Marmor MD 《The Journal of arthroplasty》2014
The aim of this study was to compare the weight of the total knee arthroplasty (TKA) implants and the weight of the natural knee. A prospective study was conducted with two different brands of cemented primary TKA. During the procedure, we collected the removed bone, soft tissues and the post-implantation cement and weighed them all separately at the end. In both groups, the implants plus cement were significantly heavier than the removed bone and soft tissues. The average weight gained was 266.7 ± 35.1 g for group 1 and 279.1 ± 48.7 g for group 2. This significant local weight gained after TKA is a new parameter that should be taken into account for further studies and when creating new implants. 相似文献