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91.
This paper proposes that an individual's self-assessed health (SAH) does not only suffer from systematic reporting bias and adaptation bias but is also biased owing to confounding health norm effects. Using 13 waves of the British Household Panel Survey covering the period 1991–2005, I show that, while there is a negative and statistically significant correlation between SAH and individuals' own health problem index, this negative effect reduces with the average number of health problems per (other) family member. The relative health bias is small, however, which implies that measures of SAH may not suffer seriously from systematic health norm bias. This is an important finding for researchers working with SAH data as it indicates that we do not have to worry too much about controlling for confounding influences from the health of other household members when estimating SAH regression equations. 相似文献
92.
目的:观察慢性乙型肝炎患者乙型肝炎病毒e系统状态和复制指标在肝纤维化发生过程中的变化及其与血清纤维化标志的关系,探讨它们在肝纤维化发生过程中的作用及其可能的临床意义.方法:188例慢性乙型肝炎患者根据肝纤维化程度分为S0~S4期等5组,分别用定量PCR及放免法检测患者血清中HBV-DNA及肝纤维化标志透明质酸、Ⅳ型胶原、Ⅲ型前胶原和层粘连蛋白的含量;HBeAg和抗-HBe采用酶联免疫吸附法(ELISA)检测,并观察其在不同肝病理纤维化分期时的变化.结果:随着肝纤维化程度加重,血清HBV-DNA含量逐渐升高,从S1期开始显著增加(P<0.01);而HBeAg阳性率逐渐降低,S3、S4期较S0显著减少(P<0.05和P<0.01);抗-HBe阳性率呈相反的变化趋势,在S3和S4期的阳性率明显高于S0期(P<0.05和P<0.01).血清HBV-DNA( )HBeAg( )组血清纤维化标志最低,HBV-DNA(-)抗-HBe( )组最高,两者差异有显著性(P<0.01).结论:HBV复制和e系统状态的改变与肝纤维化程度密切相关,肝内病毒复制标志与血清纤维化标志联合检测,对于判断肝纤维化程度和指导抗病毒治疗有重要的价值. 相似文献
93.
目的探讨血肿局部炎症、假膜新血管生成、局部纤溶状况及其在CSDH发生、发展中的作用。进而探讨CSDH的发病机制,并为CSDH的治疗及预防复发提供理论依据。方法以78例CSDH患者作为病例组,20例健康人作为正常对照组。采用ELISA法测定患者血清及血肿液中VEGF及IL-6的含量。比较患者末梢静脉血及血肿液中四种因子的含量变化并与正常对照组比较。结果病例组血肿液FDP、d-dimer检测均为阳性,血液为阴性;正常对照组血液FDP、d-dimer检测均为阴性;病例组血清VEGF含量与正常对照组比较差异无统计学意义。血肿液中VEGF浓度高于血清中。病例组血清IL-6浓度与正常对照组差异无统计学意义,血肿液中IL-6浓度高于血清中。CSDH患者血肿液VEGF、IL-6水平没有相关性。结论CSDH患者血肿液局部纤溶亢进,局部VEGF分泌旺盛,新血管生成活跃,局部炎症活跃,可导致CSDH不断扩大而参与CSDH发病机制。抗炎治疗、抑制VEGF的生理作用、有选择的对病人施行促凝治疗,可成为部分CSDH病人保守治疗及预防复发的有效手段。 相似文献
94.
慢性肝病合并细菌感染临床特点分析 总被引:3,自引:0,他引:3
目的 :分析慢性肝病合并细菌感染的特点。方法 :对 1997~ 2 0 0 2年住院的慢性重度、重症肝类及肝硬化合并细菌感染患者 52例进行回顾性分析。结果 :其中医院内感染占 2 9 8%。感染的部位 :腹腔感染 40 4% ,血液感染17 3 % ,呼吸道感染 18 1% ,肠道感染 9 6% ,胆道感染 7 7% ,口腔感染占 6 3 % ,其他感染占 3 3 % ,重型肝炎的感染率最高 ,其次为肝硬化和慢性重度肝炎。结论 :肝病患者免疫力低下 ,易于合并细菌感染 ,感染使病情加重 ,影响肝病的愈后 ;提高患者免疫力 ,增强控制医院感染的措施 ,重视潜伏感染状态病灶的处理 ,早期诊治感染可提高肝病患者的生存率 相似文献
95.
N. S. Kalson C. P. Charalambous E. S. Powell A. Hearnden J. K. Stanley 《Hand (New York, N.Y.)》2009,4(3):279-282
A common distal radio-ulnar joint (DRUJ) stabilisation procedure uses a tendon graft running from the lip of the radial sigmoid
notch to the ulnar fovea and through a bony tunnel to the ulnar shaft, before being wrapped round the distal ulna and sutured
to itself. Such graft fixation can be challenging and requires a considerable tendon length. The graft length could be reduced
by fixing the graft to the ulna using a bone anchor or interference screw. The aim of this study was to compare the strength
of three distal ulna graft fixation methods (tendon wrapping and suturing, bone anchor and interference screw). Four human
cadaveric ulnae were used. A tendon strip was run through a tunnel in the distal ulna and secured by: (1) wrapping round the
shaft and suturing it to itself, (2) a bone anchor and (3) an interference screw in the bone tunnel. Load to failure was determined
using a custom-made apparatus and an Instron machine. Maximum failure load was highest for the bone anchor fixation (99.3 ± 23.7 N)
followed by the suturing (96.2 ± 12.1 N), and the interference screw fixation (46.9 ± 5.6 N). There was no significant difference
between the tendon suturing and bone anchor methods, but the tendon suturing was statistically significantly higher compared
to the interference screw (P = 0.028). In performing anatomical stabilisation of the DRUJ fixation of the tendon graft to the distal ulna with a bone
anchor provides the most secure fixation. This may make the stabilisation technique less demanding and require a smaller tendon
graft. 相似文献
96.
John D Paulson Melissa Delgado 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2007,11(2):175-181
OBJECTIVE: This study was designed to determine the relationship between interstitial cystitis (IC), endometriosis (endo), and chronic pelvic pain (CPP) in individuals in whom nongynecological and nonurological problems had been previously ruled out. METHODS: A prospective study of 162 consecutive women with a complaint of chronic pelvic pain seen in the clinic was performed between August 2002 and December 2005. These patients underwent a workup to exclude other causes of pelvic pain, had PUF (Pain Urgency and Frequency) questionnaires filled out, and underwent a laparoscopy and a cystoscopy with hydrodistention. Pain levels were determined, and treatment was reviewed and enumerated. Results were obtained and quantified. RESULTS: In this study, 123 (76%) patients were diagnosed with active endometriosis, 133 (82%) were diagnosed with interstitial cystitis, and 107 (66%) had both disease entities simultaneously. Thirteen (8%) patients were diagnosed with pathologies unrelated to endometriosis and interstitial cystitis. Pain levels were seen to decrease at 6 months in all groups of patients with the exception of those patients with endometriosis only. CONCLUSION: CPP is a difficult, taxing, and frustrating concern for many women in the United States. These individuals have traditionally been difficult to treat. A large number of women with CPP in our patient population have been shown to have endometriosis, interstitial cystitis, or both. Therefore, a workup for premenopausal individuals with CPP involves obtaining a history that keys into possible nongynecologic causes of pain, a complete accounting of urinary problems, and a thorough history of gynecological problems. A physical examination with a comprehensive history should be performed, and the investigation may include the possibility of a simultaneous laparoscopy and cystoscopy if warranted. These procedures can serve as both a means for diagnosis and treatment of these problems when encountered. 相似文献
97.
98.
The purpose of this study was to determine if changes in hindlimb motoneuron membrane electrical properties occur 4–6 months after spinal transection in the adult animal. Eight acute and nine chronic animals were spinalized at T12. Intracellular recordings from motoneurons innervating the triceps surae were performed. Membrane electrical properties, including resting potential, action potential peak amplitude, afterhyperpolarization duration, rheobasic current, input resistance and axonal conduction velocity were measured. There were no statistical differences found between group means or frequency distributions in the membrane properties of motoneurons assessed from acute and chronic spinal animals. Thus, alteration of motoneuron membrane properties does not appear to be a major contributing factor to the hyperexcitable hindlimb reflex activity demonstrated by chronic spinal animals. 相似文献
99.
The Usefulness of Magnetic Resonance Imaging in the Diagnosis of Anterolateral Impingement of the Ankle 总被引:3,自引:0,他引:3
LCDR Doug Duncan MD CAPT Tim Mologne MD CDR Hans Hildebrand MD Mark Stanley MD LT Richard Schreckengaust MD CAPT Dave Sitler MD 《The Journal of foot and ankle surgery》2006,45(5):304-307
The purpose of this study is to assess the sensitivity and specificity of magnetic resonance imaging (MRI) in the diagnosis of anterolateral impingement of the ankle and to assess the most helpful sequence in making the diagnosis. Twenty-four patients who had undergone ankle arthroscopy were chosen. Twelve patients had arthroscopically documented anterolateral impingement, and 12 patients with no impingement on arthroscopy served as controls. Two musculoskeletal radiologists and an orthopedic surgeon, blinded to the operative diagnosis, retrospectively reviewed selective MRI images in the sagittal, axial, and coronal planes. The sensitivities and specificities were calculated for all 3 reviewers. The Kendall coefficient of concordance was calculated for overall agreement among reviewers. Sensitivities varied from 0.75 to 0.83, whereas specificities varied from 0.75 to 1.00. Using the Fisher exact test of contingency, the sensitivities and specificities showed that all reviewers' interpretations were statistically significant with P = .039, .001, and .012, respectively. The axial images were felt to be most helpful in making the diagnosis. The physicians felt that the sagittal images were helpful in 67%, 83%, and 100%, respectively. MRI is a useful tool that can aid the clinician in the diagnosis of anterolateral impingement of the ankle. T1 sagittal images demonstrating displacement of the normal fat signal anterior to the fibula by scar can be useful and help to confirm the diagnosis. 相似文献
100.
目的 观察中药高臀位灌肠治疗慢性肾功能衰竭(chronic renal failure,CRF)的临床疗效.方法 将100例CRF患者随机分为两组,治疗组70例采用中药高臀化灌肠治疗,对照组30例口服活性炭治疗.结果 治疗组总有效率为88.6%,对照组总有效率为50.0%.结论 中药高臀位灌肠治疗CRF有效. 相似文献