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41.
目的:探索膝关节前交叉韧带重建术的各个关键技术环节,为提高前交叉韧带修复的临床效果提供理论和实践依据。方法:通过分析与总结与前交叉韧带重建相关的文献资料,包括其手术方式、移植物的选择、骨道定位、髁间窝成形、移植物预张与张力、移植物固定等,同时结合作者的工作经验旨在进一步提高前交叉韧带重建技术。结果:①手术方式选择:膝关节镜下生物材料移植重建前交叉韧带取得比以往优良的临床效果,已得到广泛认可。多数采用单束重建,部分学者正在尝试双束重建以改善移植物生物力学性能。②移植材料的选择:包括自体和同种异体材料,其中自体骨-髌腱-骨与腘绳肌腱最为常用。骨-髌腱-骨由于两端带有骨块,固定牢靠,允许早期重返运动场,颇受年轻运动员青睐。腘绳肌腱取材切口小,术后很少出现膝前痛,但其稳定性不如骨-髌腱-骨,且术后相对容易出现骨隧道扩大。异体移植物在体内结合、重塑速度较自体移植慢,但若经过严格的供体筛选、合理的组织取材、消毒和保存,而不减弱移植物强度,仍可取得与自体移植相当的效果。③骨道位置:正确的骨道定位非常重要,骨道位置太靠前会造成髁间窝撞击和伸直受限。研究表明,术中采用骨性标志定位法要比采用软组织标志定位法准确,术中摄片有助于骨道位置的正确定位。④髁间窝成形术:髁间窝成形的目的是为了便于更清楚的观察髁间窝后侧,同时也是为了避免髁间窝撞击综合征的发生,由于髁间窝过度成形会增加关节出血、疼痛、肿胀以及骨赘生长,所以一般不主张广泛的髁间窝成形,除非术中确有必要时才进行。⑤移植物预张与张力:移植物初始张力不够会导致膝关节持续松弛,而张力过高会限制关节活动并加速关节退变。目前对于最佳的初始张力尚无确切说法。⑥固定:现在已经研制出许多不同类型的固定材料。对于骨-髌腱-骨而言,界面挤压螺钉单切口重建前交叉韧带时,股骨侧靠近关节腔侧固定,胫骨侧远离关节腔侧固定,双切口技术时胫骨侧靠近关节腔侧固定,股骨侧远离关节腔侧固定。股骨侧固定完毕后,膝关节取何角度对胫骨侧进行固定尚存争议。膝关节稍屈曲状态下固定不容易发生松弛,但正常的膝关节在前后方向上是允许有一定松弛度的。有些学者认为在膝关节完全伸直状态下固定可以避免屈曲挛缩畸形的发生并允许前后方向有轻度松弛。而有些学者认为在膝关节稍微屈曲状态下固定会更紧。结论:要真正做到解剖、生物力学、生理功能全方位重建,前交叉韧带重建技术,仍需不断完善,分子生物学、基因工程和组织工程技术的发展以及计算机辅助机器人手术的开展会使前交叉韧带重建技术日臻完善。  相似文献   
42.
目的:建立血虚和免疫抑制动物模型,观察鸡胚胎低温提取物对其红细胞造血以及免疫器官质量的影响。方法:实验于2001-04/2002-09在新乡医学院药物研究室完成。①实验材料:健康昆明种小鼠50只,雌雄各半。鸡胚胎素[中国发明专利公开(公告)号:CN1748713],符合研究者申报专利时提出的质量检验标准。②鸡胚胎素对血虚模型小鼠红细胞数值及血红蛋白含量的影响:取20只小鼠,随机排列表法分为鸡胚胎素组、模型对照组,10只/组,建立失血性血虚动物模型。失血后24h当红细胞数<3.2×1012L-1、血红蛋白含量<84g/L,且小鼠外观出现皮色苍白、食欲不振等现象时,代表造模成功。次日,鸡胚胎素组给予鸡胚胎素5g/(kg·d)灌胃,模型对照组给予生理盐水20mL/(kg·d)灌胃,连续14d。分别于失血前、失血后24h、末次给鸡胚胎素后2h尾部采血测定两组红细胞数量及血红蛋白含量的变化。③鸡胚胎素对免疫抑制模型小鼠免疫器官质量的影响:取30只小鼠,随机排列表法分为鸡胚胎素组、模型对照组、正常对照组,10只/组。鸡胚胎素组给予鸡胚胎素5g/(kg·d)灌胃,模型对照组和正常对照组均灌服等量生理盐水,连续14d。在第11天上午鸡胚胎素灌胃2h后,鸡胚胎素组、模型对照组腹腔注射环磷酰胺60mg/(kg·d),连续4d,复制免疫抑制动物模型。末次给予环磷酰胺2h后颈椎脱位法处死小鼠,计算胸腺、脾脏质量指数。结果:50只小鼠均进入结果分析。①失血前及失血后24h鸡胚胎素组与模型对照组的红细胞数值、血红蛋白含量基本相似(P>0.05)。末次给鸡胚胎素后2h与模型对照组比较,鸡胚胎素组红细胞数值、血红蛋白含量均明显升高(t=3.39,P<0.01;t=2.52,P<0.05)。②末次给环磷酰胺2h后与模型对照组比较,鸡胚胎素组、正常对照组的胸腺质量指数和脾脏质量指数均明显升高(t=6.62,P<0.01;t=2.47,P<0.05)。结论:鸡胚胎素灌胃对血虚小鼠具有较好的促红细胞造血功能,同时对环磷酰胺造成的免疫器官质量下降具有明显的增重作用。  相似文献   
43.
BACKGROUND: Hepatitis virus(es) that are neither hepatitis B (HBV) nor hepatitis C (HCV) (non-B, non-C [NBNC]) may be transmitted by transfusion. The present study assessed donor values for alanine aminotransferase (ALT) and antibody to hepatitis B core antigen (anti- HBc) for their association with HCV and NBNC hepatitis outcomes among allogeneic blood recipients. STUDY DESIGN AND METHODS: Data on blood donors and recipients enrolled in the Transfusion- Transmitted Viruses Study in four United States cities from 1974 through 1980 were supplemented by anti-HBc testing of donors and anti-HCV evaluation of recipients. Two statistical approaches estimated the value of these indirect tests in detecting donors associated with HCV seroconversion and NBNC hepatitis in recipients. RESULTS: For HCV cases, donor ALT alone (at > or = 60 IU/L) had a sensitivity and a specificity of 30 and 96 percent, respectively, and anti-HBc alone (at > or = 60% inhibition) had a sensitivity and specificity of 53 and 86 percent, respectively. The two markers combined had a sensitivity and a specificity of 69 and 83 percent. For NBNC hepatitis cases, each measure had low sensitivity (20%) that was not improved by using both (28%) [corrected]. CONCLUSION: The indirect tests proved to be equal in sensitivity to the first-generation anti-HCV tests. The positive predictive power of these indirect tests in the 1980s was sufficient to affect HCV incidence in studies during that period. Improved anti-HCV assays, however, replaced the need for indirect tests. The sensitivity of indirect tests for NBNC hepatitis contributed little.  相似文献   
44.
Interest in the role of intolerance of uncertainty (IU) – the tendency for a person to consider the possibility of a negative event occurring as unacceptable and threatening irrespective of the probability of its occurrence – in anxiety disorders has been increasing in recent research. IU has been implicated as an important construct associated with generalized anxiety disorder (GAD); however, a growing body of research suggests that levels of IU are also high among individuals with other anxiety disorders. Despite the increasing interest, few studies have examined the relationship between IU and social anxiety (SA). The purpose of the present investigation was to further investigate the relationship between IU and SA. Participants included 286 community members (71% women) from Canada who completed measures of IU, SA, anxiety sensitivity, and fear of negative evaluation (FNE). Regression analyses revealed that the inhibitory anxiety dimension of IU, the fear of socially observable anxiety symptoms dimension of anxiety sensitivity, and the FNE were consistently significant predictors of SA symptoms. Unexpectedly, IU and FNE were often comparable predictors of SA variance. Moreover, participants with SA symptoms consistent with SAD exhibited levels of IU comparable to those reported by participants with worry symptoms consistent with GAD. Comprehensive findings, implications, and directions for future research are discussed.  相似文献   
45.

BACKGROUND:

Diagnosing pulmonary tuberculosis (PTB) is challenging in patients who are unable to spontaneously expectorate. Published evidence suggests that induced sputum (IS) is the least invasive and most cost-effective method of diagnosis, and should be used before fibre-optic bronchoscopy (FOB).

METHODS:

The medical records of 337 adults treated for PTB in northern Alberta between 1997 and 2007 were reviewed to determine whether local practice patterns reflect the evidence. Microbiological data were collected from the Provincial Laboratory for Public Health. Demographic information was collected from the patients’ charts.

RESULTS:

A total of 8.5% (26 of 307) of PTB patients had IS collected, whereas 35.8% (110 of 307) underwent FOB. Among FOB patients, 56.4% (62 of 110) had no sputum sent before the procedure and 29% (18 of 62) of these patients were smear positive. Only five patients referred for FOB had IS sent previously. There were no demographic factors predictive of IS use, whereas being an inpatient at a teaching facility or having a nodule or mass on chest x-ray was predictive of FOB referral. Because so few IS samples were available, not all patients had spontaneously expectorated sputum, IS and FOB tests performed; thus, the calculated yields were not comparable with one another.

CONCLUSIONS:

Despite published evidence recommending IS collection before FOB referral in suspected PTB patients, clinicians in our health region appeared to prefer early FOB over IS by a large margin. This practice pattern is less cost effective and exposes patients and health care workers to greater risk. Further research is needed to identify the reasons for the underuse of sputum induction.  相似文献   
46.
Fear–anxiety–avoidance models posit pain-related anxiety and anxiety sensitivity as important contributing variables in the development and maintenance of chronic musculoskeletal pain [Asmundson, G. J. G, Vlaeyen, J. W. S., & Crombez, G. (Eds.). (2004). Understanding and treating fear of pain. New York: Oxford University Press]. Emerging evidence also suggests that pain-related anxiety may be a diathesis for many other emotional disorders [Asmundson, G. J. G., & Carleton, R. N. (2005). Fear of pain is elevated in adults with co-occurring trauma-related stress and social anxiety symptoms. Cognitive Behaviour Therapy, 34, 248–255; Asmundson, G. J. G., & Carleton, R. N. (2008). Fear of pain. In: M. M. Antony & M. B. Stein (Eds.), Handbook of anxiety and the anxiety disorders (pp. 551–561). New York: Oxford University Press] and appears to share several elements in common with other fears (e.g., anxiety sensitivity, illness/injury sensitivity, fear of negative evaluation) as described by Reiss [Reiss, S. (1991). Expectancy model of fear, anxiety, and panic. Clinical Psychology Review, 11, 141–153] and Taylor [Taylor, S. (1993). The structure of fundamental fears. Journal of Behavior Therapy and Experimental Psychiatry, 24, 289–299]. The purpose of the present investigation was to assess self-reported levels of pain-related anxiety [Pain Anxiety Symptoms Scale-Short Form; PASS-20; McCracken, L. M., & Dhingra, L. (2002). A short version of the Pain Anxiety Symptoms Scale (PASS-20): preliminary development and validity. Pain Research and Management, 7, 45–50] across several anxiety and depressive disorders and to compare those levels to non-clinical and chronic pain samples. Participants consisted of a clinical sample (n = 418; 63% women) with principal diagnoses of a depressive disorder (DD; n = 22), panic disorder (PD; n = 114), social anxiety disorder (SAD; n = 136), obsessive-compulsive disorder (OCD; n = 86), generalized anxiety disorder (GAD; n = 46), or specific phobia (n = 14). Secondary group comparisons were made with a community sample as well as with published data from a treatment-seeking chronic pain sample [McCracken, L. M., & Dhingra, L. (2002). A short version of the Pain Anxiety Symptoms Scale (PASS-20): preliminary development and validity. Pain Research and Management, 7, 45–50]. Results suggest that pain-related anxiety is generally comparable across anxiety and depressive disorders; however, pain-related anxiety was typically higher (p < .01) in individuals with anxiety and depressive disorders relative to a community sample, but comparable to or lower than a chronic pain sample. Results imply that pain-related anxiety may indeed be a construct independent of other fundamental fears, warranting subsequent hierarchical investigations and consideration for inclusion in treatments of anxiety disorders. Additional implications and directions for future research are discussed.  相似文献   
47.
Background: Tonic immobility (TI) is a temporary state of motor inhibition believed to be a response to situations involving extreme fear. Limited attention has been directed to studying TI in humans; however, the phenomenon has been well documented in the animal literature. In humans, TI is believed to occur during sexual assault, and there have been reports of fear‐induced freezing in the contexts of air, naval, and other disasters. Methods: This study had three main purposes: (1) to assess the factor structure of a new self‐report measure—the Tonic Immobility Questionnaire 1 —designed to assess human TI in a range of traumatic events; (2) to explore associations among discovered TIQ factors and a measure of posttraumatic symptoms in the context of trauma type; and (3) to determine whether TI is related to suspected and empirically supported predictors of posttraumatic stress disorder. Participants were a subset of undergraduate students (n=78) who reported a TI experience in the context of a traumatic event. Results: No differences were found in frequency or severity of TI reported across trauma types. Exploratory factor analysis of Tonic Immobility Questionnaire item responses resulted in a three‐factor solution (i.e., physical immobility, fear, and dissociation). Significant positive correlations were found between the Tonic Immobility Questionnaire and measures of posttraumatic symptoms, dissociation, anxiety sensitivity, and absorption. Regression analysis revealed that peritraumatic dissociation scores alone accounted for 51% of the variance in TI scores. Conclusions: TI may represent an extreme behavioral expression of trauma‐induced peritraumatic dissociation. Implications and directions for future research are discussed. Depression and Anxiety, 2009.© 2009 Wiley‐Liss, Inc.  相似文献   
48.
CONTEXT: Although military personnel are trained for combat and peacekeeping operations, accumulating evidence indicates that deployment-related exposure to traumatic events is associated with mental health problems and mental health service use. OBJECTIVE: To examine the relationships between combat and peacekeeping operations and the prevalence of mental disorders, self-perceived need for mental health care, mental health service use, and suicidality. DESIGN: Cross-sectional, population-based survey. SETTING: Canadian military. PARTICIPANTS: A total of 8441 currently active military personnel (aged 16-54 years). MAIN OUTCOME MEASURES: The DSM-IV mental disorders (major depressive disorder, posttraumatic stress disorder, generalized anxiety disorder, panic disorder, social phobia, and alcohol dependence) were assessed using the World Mental Health version of the World Health Organization Composite International Diagnostic Interview, a fully structured lay-administered psychiatric interview. The survey included validated measures of self-perceived need for mental health treatment, mental health service use, and suicidal ideation. Lifetime exposure to peacekeeping and combat operations and witnessing atrocities or massacres (ie, mutilated bodies or mass killings) were assessed. RESULTS: The prevalences of any past-year mental disorder assessed in the survey and self-perceived need for care were 14.9% and 23.2%, respectively. Most individuals meeting the criteria for a mental disorder diagnosis did not use any mental health services. Deployment to combat operations and witnessing atrocities were associated with increased prevalence of mental disorders and perceived need for care. After adjusting for the effects of exposure to combat and witnessing atrocities, deployment to peacekeeping operations was not associated with increased prevalence of mental disorders. CONCLUSIONS: This is the first study to use a representative sample of active military personnel to examine the relationship between deployment-related experiences and mental health problems. It provides evidence of a positive association between combat exposure and witnessing atrocities and mental disorders and self-perceived need for treatment.  相似文献   
49.

Background and purpose:

We investigated the effects of a synthetic flavonol, 3′,4′-dihydroxyflavonol (DiOHF) on the expression of monocyte chemoattractant protein-1 (MCP-1) in rat vascular smooth muscle cells.

Experimental approach:

MCP-1 expression was assessed by quantitative real-time PCR and protein phosphorylation by immunoprecipitation and Western blots.

Key results:

DiOHF (1–30 µmol·L−1) concentration-dependently reduced MCP-1 expression in both quiescent cells and cells stimulated with platelet-derived growth factor (PDGF) or interleukin 1-β. The effect of DiOHF was associated with a suppression of focal adhesion kinase (FAK)-mediated signalling. In vitro kinase assays demonstrated that DiOHF is a potent inhibitor of FAK kinase activity (EC50= 2.4 µmol·L−1). Expression of FAK-related non-kinase reduced basal MCP-1 expression, but not that induced by PDGF or interleukin 1-β. DiOHF also inhibited autophosphorylation of PDGF receptors. The PDGF receptor inhibitor AG-1296 potently suppressed basal and PDGF-induced MCP-1 expression. Inhibition of extracellular signal-regulated kinase activation by DiOHF, either directly or indirectly, may also be involved in its effects on MCP-1 expression. DiOHF had no inhibitory effect on either p38 or nuclear factor-κB activation. Moreover, DiOHF inhibited smooth muscle cell spreading (a FAK-mediated response) and proliferation.

Conclusions and implications:

This is the first report on a flavonoid compound (DiOHF) that is a potent FAK inhibitor. DiOHF also inhibits PDGF receptor autophosphorylation. These effects underlie the inhibitory action of DiOHF on MCP-1 expression in smooth muscle cells. Our results suggest that DiOHF might be a useful tool for dissection of the (patho)physiological roles of FAK signalling.British Journal of Pharmacology (2009) 157, 597–606; doi:10.1111/j.1476-5381.2009.00199.x; published online 9 April 2009  相似文献   
50.
Sleep paralysis (SP) occurs when rapid eye movement (REM) activity and concomitant paralysis of the skeletal muscles persist as an individual awakens and becomes conscious of his/her surroundings. SP is often accompanied by frightening hallucinations that some researchers suggest may be confounded with memories of childhood sexual abuse (CSA; [McNally, R. J., & Clancy, S. A. (2005). Sleep paralysis in adults reporting repressed, recovered, or continuous memories of childhood sexual abuse. Journal of Anxiety Disorders, 19, 595-602]). The purpose of this study was to evaluate relationships between CSA and SP. Based on self-report, participants (n=263) were categorized into three CSA groups: confirmed, unconfirmed, or no history of CSA. Relative to participants reporting no CSA history, those reporting CSA reported more frequent and more distressing episodes of SP. Post hoc analyses revealed that participants with clinically significant post-traumatic symptoms (irrespective of CSA history) also reported more frequent and more distressing episodes of SP. Significant correlations were found among SP indices and measures of post-traumatic symptoms, depression, dissociation, and absorption. Implications and future research directions are discussed.  相似文献   
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