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991.
Allison L Kuipers Heartley Egwuogu Rhobert W Evans Alan L Patrick Ada Youk Clareann H Bunker Joseph M Zmuda 《Journal of bone and mineral research》2015,30(12):2215-2220
Poor renal function is associated with increased rates of bone loss and osteoporotic fractures in Caucasian men. The importance of kidney function for skeletal health in African ancestry men, who are a population segment with a high prevalence of chronic kidney disease as well as high peak bone mass, is not well known. We examined the relationship between estimated glomerular filtration rate (eGFR) and rates of bone loss in a large population cohort of otherwise healthy Afro‐Caribbean men aged 40 years and older. Dual X‐ray absorptiometry of the proximal femur and quantitative computed tomography of the proximal radius and tibia were obtained approximately 6 years apart. We calculated eGFR from serum creatinine that was measured in fasting samples in 1451 men. Impaired kidney function (IKF, eGFR<60 ml/min/1.7 m2) was observed in 8.6% of the cohort. The relationship between IKF and baseline BMD and annualized rate of change in BMD was analyzed controlling for potentially important confounders. IKF was not associated with baseline BMD. In contrast, men with IKF experienced a rate of decline in areal BMD at the total hip, femoral neck and trochanter and cortical volumetric BMD compared to those with normal kidney function (p<0.05 for all). Impaired kidney function was not associated with changes in trabecular volumetric BMD. In conclusion, poorer kidney function is associated with accelerated bone loss among otherwise healthy Afro‐Caribbean men even after controlling for age and other important medical and lifestyle related variables. © 2015 American Society for Bone and Mineral Research. 相似文献
992.
993.
Osman Civil Metin Kement Nuri Okkabaz Mustafa Haksal Cem Gezen Mustafa Oncel 《The Indian journal of surgery》2015,77(4):276-282
The bipolar radiofrequency device (Habib®) has been recently introduced in order to reduce intraoperative bleeding for a safe hepatic resection as an alternative to the conventional tools. However, indications, perioperative findings, and outcome of the device for hepatic resections remain and deserve to be analyzed. The current study aims to analyze the feasibility of the bipolar radiofrequency device (Habib®) for hepatic resections. Information of the patients that underwent hepatic resection using with the Habib® device between 2007 and 2011 was abstracted. Patient, disease, and operation-related findings and perioperative data were investigated. A total of 71 cases (38 [53.5 %] males, mean age was 56.8 ± 11.9) were analyzed. Metastatic disease (n = 55; 77.5 %) was the leading indication followed by primary liver and biliary malignancies (n = 7; 9.9 %), hemangioma (n = 5; 7 %), hydatid disease (n = 3; 2.8 %), and hepatic gunshot trauma (n = 1; 1.4 %). Metastasectomy was the most commonly performed procedure (n = 31; 56.3 %), but in 24 (77.4 %) cases, it was performed in addition to extended resections. Other procedures in the study patients include segmentectomy in 17, bisegmentectomy in 19, trisegmentectomy in 17, right or left hepatectomy in 8, and extended right/left hepatectomy in 3. The mean (±SD) operation time was 241.7 ± 78.2 min. The median amount of bleeding was 300 cc (range 25–2500), and 23 (32.4 %) cases required perioperative transfusion. The median hospitalization period was 5 days (range 1–47). Lengthened drainage (n = 9, 12.7 %) and intraabdominal abscess (n = 8, 11.23 %) were the most common problems. Hepatic resections using the Habib® device seem to be feasible in cases with primary and metastatic hepatic lesions and benign liver masses and even those with hepatic trauma. It may lessen the amount of intraoperative hemorrhage, although lengthened drainage and intraabdominal abscess were the major postoperative problems in these cases. 相似文献
994.
Riccardo D’Ambrosi Carlo Perfetti Guido Garavaglia Ettore Taverna 《International journal of shoulder surgery》2015,9(3):94-98
This case presents the challenges of the surgical management for a patient with a history of recurrent posterior shoulder instability and subsequently traumatic anterior dislocation. The patient was already on the waiting list for an arthroscopic posterior stabilization with anchors, when a car accident caused an additional anterior shoulder dislocation. This traumatic anterior dislocation created a bone loss with a glenoid fracture and aggravated the preexisting posterior instability. In order to address both problems, we decided to perform an arthroscopically assisted Latarjet procedure for anterior instability and to stabilize with a bone graft for posterior instability. To our best knowledge, this type of surgical procedure has so far never been reported in the literature. The purpose of this report is to present the surgical technique and to outline the decision making process. 相似文献
995.
股骨颈骨折生物型全髋关节置换术后放置真空负压引流对围手术期失血量影响的病例对照研究 总被引:1,自引:1,他引:0
目的 :比较股骨颈骨折全髋置换术后放置真空负压引流瓶,不同负压下术后失血量的差异。方法 :选取2013年1月1日至2013年12月30日采用生物型全髋关节置换术治疗的74例股骨颈骨折患者,分成高负压引流组和低负压引流组。高负压引流组34例,男10例,女24例;平均年龄(75.94±9.02)岁;术毕放置60 k Pa负压真空负压引流瓶。低负压引流组40例,男13例,女27例;平均年龄(74.93±8.90)岁;术毕放置30 k Pa负压真空负压引流瓶。对术后伤口引流量、血红蛋白改变值、根据身高体重和手术前后红细胞压积(Hct)计算的所有患者总失血量等进行观察,并做统计学分析进行比较。结果:两组患者术后切口均Ⅰ期愈合,无感染发生。术后第1天,高负压引流组血红蛋白改变值为(41.74±15.69)g/L,总失血量(1 217.73±459.50)ml,术后引流量(312.94±103.44)ml;低负压引流组血红蛋白改变值(34.90±12.90)g/L,总失血量(904.01±381.58)ml,术后引流量(129.25±44.25)ml,高负压引流组的数值均高于低负压引流组。术后3 d,高负压引流组血红蛋白改变值为(46.00±13.29)g/L,总失血量(1 304.72±421.75)ml;低负压引流组血红蛋白改变值为(43.87±11.39)g/L,总失血量(1 196.78±344.20)ml,两组差异无统计学意义。结论:股骨颈骨折生物型全髋关节置换术后放置引流时,根据患者术前血红蛋白、红细胞压积等情况选择负压引流压力大小,老年性股骨颈骨折选择低负压引流更为合适。 相似文献
996.
目的:探讨载三联抗结核药物硫酸钙/聚氨基酸人工材料在模拟体液中的药物缓释性能。方法:避光环境下以100:3:3:12的比例称取硫酸钙/氨基酸复合材料500mg、异烟肼(isoniazid,INH)15mg、利福平(rifampicin,RFP)15mg、吡嗪酰胺(pyrazinamide,PZA)60mg制备载药人工缓释材料,将其置于模拟体液中,分别于浸泡3h、12h、24h、36h、48h、60h、72h、1~14周时取材料浸提液,应用高效液相色谱法(HPLC)检测其中INH、RFP、PZA三种药物的浓度,并据其计算单位时间段内药物释出质量。结果:载三联抗结核药的硫酸钙/聚氨基酸人工材料在模拟体液中浸泡3h时浸提液中释出INH、RFP、PZA的浓度分别达到152.96±1.32μg/ml、92.90±2.17μg/ml和334.90±12.3μg/ml,在8周前各时间点的浸提液中,3种药物浓度均较高;至8周时PZA的释出浓度、10周时RFP释出浓度、11周时INH的释出浓度仍高于其10倍的最小抑菌浓度,之后逐渐降低;未载药硫酸钙/聚氨基酸人工材料在有效检测时间内药物出峰时间处未见有意义杂质峰出现。结论:载三联抗结核药硫酸钙/聚氨基酸人工材料具有较为平稳、持续时间较长的有效缓释性能,三种药物在模拟体液中释出药物的浓度均可达到体内杀死结核分枝杆菌的浓度。 相似文献
997.
利用全细胞膜片钳技术,观察不同浓度地塞米松急性灌洗大鼠肾上腺嗜铬细胞(AMCC)后钙通道电流和烟碱受体通道电流(INIC)的变化,地塞米松对大鼠AMCC的急性作用为明显抑制INIC而对电刺激所诱发的钙通道电流无明显影响,提示糖皮质激素对大鼠AMCC分泌儿茶酚胺的急性效应可能与烟碱受体直接相关。 相似文献
998.
In situ Ca2+ dynamics of Purkinje fibers and its interconnection with subjacent ventricular myocytes
Hamamoto T Tanaka H Mani H Tanabe T Fujiwara K Nakagami T Horie M Oyamada M Takamatsu T 《Journal of molecular and cellular cardiology》2005,38(4):561-569
Purkinje fibers play essential roles in impulse propagation to the ventricles, and their functional impairment can become arrhythmogenic. However, little is known about precise spatiotemporal pattern(s) of interconnection between Purkinje-fiber network and the underlying ventricular myocardium within the heart. To address this issue, we simultaneously visualized intracellular Ca(2+) dynamics at Purkinje fibers and subjacent ventricular myocytes in Langendorff-perfused rat hearts using multi-pinhole type, rapid-scanning confocal microscopy. Under recording of electrocardiogram at room temperature spatiotemporal changes in fluo3-fluorescence intensity were visualized on the subendocardial region of the right-ventricular septum. Staining of the heart with either fluo3, acetylthiocholine iodide (ATCHI), or di-4-ANEPPS revealed characteristic structures of Purkinje fibers. During sinus rhythm (about 60 bpm) or atrial pacing (up to 3 Hz) each Purkinje-fiber exhibited spatiotemporally synchronous Ca(2+) transients nearly simultaneously to ventricular excitation. Ca(2+) transients in individual fibers were still synchronized within the Purkinje-fiber network not only under high-K(+) (8 mM) perfusion-induced Purkinje-to-ventricular (P-V) conduction delay, but also under unidirectional, orthodromic P-V block produced by 10-mM K(+) perfusion. While spontaneous, asynchronous intracellular Ca(2+) waves were identified in injured fibers of Purkinje network locally, surrounding fibers still exhibited Ca(2+) transients synchronously to ventricular excitation. In summary, these results are the first demonstration of intracellular Ca(2+) dynamics in the Purkinje-fiber network in situ. The synchronous Ca(2+) transients, preserved even under P-V conduction disturbances or under emergence of Ca(2+) waves, imply a syncytial role of Purkinje fibers as a specialized conduction system, whereas unidirectional block at P-V junctions indicates a substrate for reentrant arrhythmias. 相似文献
999.
Masatsugu Hori Hideyuki Sato Michiko Karita Kazuhisa Kodama Noritake Hoki Tohru Hayashi Masashi Naka Shinsuke Nanto Yoshio Yamada Takenobu Kamada 《Heart and vessels》1994,9(5):249-253
Summary The long-term effect of calcium channel blockers on chronic heart failure is disappointing, probably because of reflex sympathetic activation through arterial vasodilation. However, nilvadipine may be beneficial for treatment of chronic heart failure since this drug has minimal effects on sympathetic activation. In this study, the effects of 12-week administration of nilvadipine or placebo on symptoms of heart failure and cardiac function were investigated in 23 patients with mild-to-moderate chronic heart failure in a double-blind trial. The patients were randomly assigned to either a nilvadipine group (16 mg daily) or a placebo group. Intergroup comparisons did not show significant differences in any parameters. Serious adverse effects were not observed during the study. Thus, this study failed to show any beneficial effect of nilvadipine in the long-term treatment of patients with chronic heart failure. We conclude that the long-term administration of nilvadipine (16 mg daily) is neither effective nor harmful in the treatment of patients with chronic heart failure.Other members are listed in the appendix. 相似文献
1000.
平滑肌细胞源性趋化因子所致单核细胞迁移的钙依赖性研究 总被引:4,自引:0,他引:4
本文以培养的兔主动脉平滑肌细胞条件培养基作为趋化因子的来源,用改良的Boyden小室微孔滤膜法进行单核细胞的迁移试验,并观察戊脉胺和细胞外Ca2+对其影响。用Fura-2检测单核细胞胞液游离钙浓度,并观察上述条件培养基及戊脉胺对其影响。结果表明,该条件培养基对单核细胞有明显趋化作用并被戊脉胺所抑制;它也能明显地升高单核细胞胞液游离钙浓度,并被戊脉胺所抑制。细胞外Ca2+也能影响单核细胞的迁移。以上结果提示,单核细胞迁移对细胞内、外Ca2+均有依赖性。 相似文献