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1.
BACKGROUND: This study was undertaken to investigate the effect of long-term blood pressure (BP) reduction, achieved with salt restriction and strict volume control, on frequency and regression of left ventricular hypertrophy (LVH) in long-term peritoneal dialysis (PD) patients. METHODS: 56 patients who had been treated for more than 2 years under our care were enrolled. After echocardiographic (Echo) evaluation, 46 patients were included in the follow-up study. In our unit, we aim to keep patients' BP below 130/85 mmHg and cardiothoracic index below 0.50. To reach these targets, moderate salt restriction is advised, and if necessary, hypertonic PD solutions are used. Echo was performed at the beginning of the study (after a mean period of 36 months on PD) and at the end of the prospective follow-up period (24 months later). RESULTS: At the time of the first Echo, LVH was detected in only 8 (21%) patients. Residual urine volume was significantly decreased compared to data taken when they first started PD (658 +/- 795 vs 236 +/- 307 mL/day). Mean left ventricular mass index (LVMI) was 107 +/- 26.5 g/m2. LVMI was significantly decreased at the end of the follow-up in patients who had LVH at baseline. No LVH developed in patients who had normal LVMI at baseline. CONCLUSION: Our results indicate that control of hypertension is possible when extracellular fluid volume is kept under control using hypertonic PD solutions in case of recruitment in addition to salt restriction in long-term PD patients. Sustained normovolemia is associated with low incidence and regression of LVH.  相似文献   
2.
输卵管积水造口术对体外受精与胚胎移植的影响   总被引:2,自引:0,他引:2  
【目的】探讨在体外受精与胚胎移植 (IVF ET)之前输卵管积水患者行输卵管造口术对IVF ET治疗效果的影响。【方法】回顾分析 1999年 2月至 2 0 0 1年 1月因女性输卵管因素不孕行IVF ET治疗的 90 8个周期的资料。按输卵管积水患者在IVF ET前是否治疗分 3组 ,A组 :输卵管积水未手术治疗行IVF ET 2 3个周期 ,B组 :在IVF ET之前行输卵管积水造口术 (腹腔镜下或开腹 ) 2 2个周期 ,C组 :对照组 (输卵管阻塞 ,未发现输卵管积水 ) 86 3个周期。【结果】A组、B组、C组的IVF ET的种植率分别为 9 7%、17 9%、16 7% ,临床妊娠率分别为 2 1 7%、4 0 9%、39 2 %。A组的种植率及临床妊娠率比其它组低 ,经 χ2 检验 ,有统计学意义。【结论】输卵管积水未治疗行IVF ET的种植率及临床妊娠率较低 ,但在IVF ET之前行输卵管造口术可改善IVF ET的种植率及临床妊娠率  相似文献   
3.
When left bundle branch block (LBBB) is present on the electrocardiogram, the diagnosis of left ventricular hypertrophy (LVH) may be difficult. The left ventricular mass in 70 patients with LBBB was estimated by echocardiography, and was compared to the QRS configuration on the electrocardiogram. We found that there was agreement between a monophasic R pattern in lead 1 or V6 (sensitivity 79.3%, 70.7%) and left ventricular hypertrophy. We suggest that a monophasic R pattern in L1 and V6 may provide a useful simple index of left ventricular hypertrophy in the presence of left bundle branch block.  相似文献   
4.
Since humans are under ceaseless orthostatic stress, the mechanism to maintain arterial pressure (AP) under orthostatic stress against gravitational fluid shift is of great importance. We hypothesized that (1) orthostatic stress resets the arterial baroreflex control of sympathetic nerve activity (SNA) to a higher SNA, and (2) resetting of the arterial baroreflex contributes to preventing postural hypotension. Renal SNA and AP were recorded in eight anaesthetized, vagotomized and aortic-denervated rabbits. Isolated intracarotid sinus pressure (CSP) was increased stepwise from 40 to 160 mmHg with increments of 20 mmHg (60 s for each CSP level) while the animal was placed supine and at 60 deg upright tilt. Upright tilt shifted the CSP–SNA relationship (the baroreflex neural arc) to a higher SNA, shifted the SNA–AP relationship (the baroreflex peripheral arc) to a lower AP, and consequently moved the operating point to marked high SNA while maintaining AP. A simulation study suggests that resetting in the neural arc would double the orthostatic activation of SNA and increase the operating AP in upright tilt by 10 mmHg, compared with the absence of resetting. In addition, upright tilt did not change the CSP–AP relationship (the baroreflex total arc). A simulation study suggests that although a downward shift of the peripheral arc could shift the total arc downward, resetting in the neural arc would compensate this fall and prevent the total arc from shifting downward to a lower AP. In conclusion, upright tilt increases SNA by resetting the baroreflex neural arc. This resetting may compensate for the reduced pressor responses to SNA in the peripheral cardiovascular system and contribute to preventing postural hypotension.  相似文献   
5.
目的分析1组Goldenhar综合征家系的临床表现及遗传学特征。方法我们随访到1组4代33人的Goldenhar综合征家系,对目前存活的29人进行了临床表型和遗传学的初步分析。结果家系内有Goldenhaar综合征患者5人.临床表现具高度多样性,累及眼、耳、脊柱、颜面、口腔等多个器官和系统的发育不良,在遗传方式上属于常染色体显性遗传。从细胞遗传学水平对家系中成员进行染色体检查,未发现核型异常。结论该Goldenhar综合征家系属常染色体显性遗传,染色体检查未发现核型异常。  相似文献   
6.
Summary High-resolution computed tomography (HRCT) provides excellent contrast between osseous structures, air and soft tissue in conjunction with high spatial resolution. Therefore, thin-section HRCT with bone window setting is the method of choice for the examination of the middle ear structures. The indications are acute and chronic inflammatory changes, cholesteatoma and tumor, the “postoperative middle ear”, and malformations. In most cases, HRCT enables differentiation between inflammatory changes, cholesteatoma, and tumor. The excellent depiction of subtle osseous details enables the identification of erosions of the ossicles or of the bony walls of the mastoid cells, of osseous defects of the tegmen, of the bony labyrinth, and of the tympanic course of the facial canal. In addition, HRCT enables excellent depiction of reconstructions of the ossicles or prosthesis of the ossicles. Although HRCT is the first method of choice, magnetic resonance imaging (MRI) may provide additional information and lead to a more accurate diagnosis in some cases. This is explained by the excellent soft tissue contrast provided by MRI. In addition, MRI offers the possibility of using various pulse sequences and the administration of IV contrast material. Therefore, MRI may allow the differentiation between inflammatory changes, cholesteatoma, and tumor in those cases in which accurate diagnosis cannot be made by HRCT. The differentiation between a meningocele or meningoencephalocele and other entities such as tumors or cholesteatoma can be established by MRI. Furthermore, MRI can accurately depict cases of labyrinthitis or of neuritis of the facial nerve or of intracranial disease caused by middle ear processes, while this is not always possible by HRCT. In summary, HRCT of the middle ear is the method of choice, but MRI may provide supplementary information in those cases in which accurate diagnosis cannot be established by HRCT.   相似文献   
7.
额叶内侧面损伤的临床特点及救治   总被引:9,自引:0,他引:9  
目的 总结17例额叶内侧面损伤的临床特点及救治经验。方法 对我科1999年7月至2003年4月收治的额叶内侧面损伤患者进行回顾性分析。结果 手术治疗1例,恢复良好,保守治疗16例,其中恢复良好12例,中残2例,死亡2例,全组死亡率11.77%。结论 额叶内侧面损伤一般意识障碍较轻,但易直接发生枕骨大孔疝,严密观察病情及动态CT检查,颅内压监测,不拘泥传统手术指征,及时抓住手术时机,可有效降低致残率及死亡率。  相似文献   
8.
A neurotrophic model for stress-related mood disorders.   总被引:31,自引:0,他引:31  
There is a growing body of evidence demonstrating that stress decreases the expression of brain-derived neurotrophic factor (BDNF) in limbic structures that control mood and that antidepressant treatment reverses or blocks the effects of stress. Decreased levels of BDNF, as well as other neurotrophic factors, could contribute to the atrophy of certain limbic structures, including the hippocampus and prefrontal cortex that has been observed in depressed subjects. Conversely, the neurotrophic actions of antidepressants could reverse neuronal atrophy and cell loss and thereby contribute to the therapeutic actions of these treatments. This review provides a critical examination of the neurotrophic hypothesis of depression that has evolved from this work, including analysis of preclinical cellular (adult neurogenesis) and behavioral models of depression and antidepressant actions, as well as clinical neuroimaging and postmortem studies. Although there are some limitations, the results of these studies are consistent with the hypothesis that decreased expression of BDNF and possibly other growth factors contributes to depression and that upregulation of BDNF plays a role in the actions of antidepressant treatment.  相似文献   
9.
Pten基因敲除对过氧化物酶家族表达和活性氧水平的影响   总被引:2,自引:0,他引:2  
目的:探讨Pten基因敲除后对过氧化物酶家族(Peroxiredoxins,Prdxs)水平和活性氧水平的影响.方法:采用Western印迹和化学/荧光发光分析法分别检测了在Pten / MEF和Pten-/-MEF细胞中PRDXs的表达和细胞内活性氧水平.结果:Western印迹结果显示,与Pten / MEF细胞相比,Pten-/-MEF细胞PRDX Ⅰ,Ⅱ,Ⅴ,Ⅵ蛋白水平下调,PRDX Ⅲ不变,PRDX Ⅳ上调.DCFH探针标记后流式结果显示Pten-/-MEF 细胞活性氧荧光值显著高于对照Pten / MEF细胞(P<0.05).结论:Pten基因敲除引起数种PRDXs表达下调,细胞内活性氧水平增高.  相似文献   
10.
【目的】探讨种植前基因诊断的临床应用。【方法】对 1例夫妇均为东南亚缺失型α 地中海贫血携带者 ,经超排取卵、卵母细胞单精子显微注射受精及胚胎细胞活检 ,吸取的单个卵裂球采用针对α SEA基因的 gap PCR引物和荧光探针用荧光定量PCR技术进行诊断 ,将诊断为不致病的 3个胚胎进行宫腔内移植。【结果】胚胎移植后 7周B超诊断单胎妊娠 ,18周羊膜腔穿刺产前诊断证实为不致病胎儿。【结论】应用成熟的显微操作技术进行胚胎细胞活检 ,活检的单个卵裂球用荧光定量PCR技术进行诊断 ,获得国内首例α 地中海贫血胚胎种植前基因诊断后妊娠成功。  相似文献   
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