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1.
A variety of small-bowel malignant neoplasms have been reported in association with nontropical sprue (celiac disease). Lymphomas have been the most common malignant neoplasms to complicate this disease. However, adenocarcinoma of the small bowel has infrequently been reported. The suggestion has been made that patients with nontropical sprue are at increased risk for developing small-bowel adenocarcinoma. Three additional cases of small-bowel adenocarcinoma in association with nontropical sprue are reported.  相似文献   

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Context:

Quadriceps dysfunction is a common consequence of knee joint injury and disease, yet its causes remain elusive.

Objective:

To determine the effects of pain on quadriceps strength and activation and to learn if simultaneous pain and knee joint effusion affect the magnitude of quadriceps dysfunction.

Design:

Crossover study.

Setting:

University research laboratory.

Patients or Other Participants:

Fourteen (8 men, 6 women; age = 23.6 ± 4.8 years, height = 170.3 ± 9.16 cm, mass = 72.9 ± 11.84 kg) healthy volunteers.

Intervention(s):

All participants were tested under 4 randomized conditions: normal knee, effused knee, painful knee, and effused and painful knee.

Main Outcome Measure(s):

Quadriceps strength (Nm/kg) and activation (central activation ratio) were assessed after each condition was induced.

Results:

Quadriceps strength and activation were highest under the normal knee condition and differed from the 3 experimental knee conditions (P < .05). No differences were noted among the 3 experimental knee conditions for either variable (P > .05).

Conclusions:

Both pain and effusion led to quadriceps dysfunction, but the interaction of the 2 stimuli did not increase the magnitude of the strength or activation deficits. Therefore, pain and effusion can be considered equally potent in eliciting quadriceps inhibition. Given that pain and effusion accompany numerous knee conditions, the prevalence of quadriceps dysfunction is likely high.Key Words: arthrogenic muscle inhibition, central activation failure, voluntary activation, muscles

Key Points

  • Knee pain and effusion resulted in arthrogenic muscle inhibition and weakness of the quadriceps.
  • The simultaneous presence of pain and effusion did not increase the magnitude of quadriceps dysfunction.
  • To reduce arthrogenic muscle inhibition and improve muscle strength, clinicians should employ interventions that target removing both pain and effusion.
Quadriceps weakness is a common consequence of traumatic knee joint injury1,2 and chronic degenerative knee joint conditions.3,4 Arthrogenic muscle inhibition (AMI), a neurologic decline in muscle activation, results in quadriceps weakness and hinders rehabilitation by preventing gains in strength.5 The inability to reverse AMI and restore muscle function can lead to decreased physical abilities,6 biomechanical deficits,7 and possibly reinjury.5 Furthermore, researchers8,9 have suggested that quadriceps weakness resulting from AMI may place patients at risk for developing osteoarthritis in the knee. In light of the substantial influence of quadriceps AMI on these clinically relevant outcomes, we need to improve our understanding of the factors that contribute to this neurologic decline in muscle activity so efforts to target and reverse it can be implemented and gains in strength can be achieved more easily.Joint injury and disease are accompanied by numerous sequelae (ie, pain, swelling, tissue damage, inflammation), so ascertaining which one ultimately leads to neurologic muscle dysfunction is difficult. Whereas a joint effusion can result in AMI,1012 the effects of pain are less understood despite many clinicians attributing AMI to pain. Using techniques that introduce knee pain without accompanying injury may provide insights into the role of pain in eliciting AMI.The degree of knee joint damage may play a role in the quantity of AMI that manifests. Hurley et al13,14 demonstrated that quadriceps AMI, measured using an interpolated-twitch technique, was greater in patients with extensive traumatic knee injury (eg, fractured tibial plateau, ruptured medial collateral ligament, and medial meniscectomy) than patients with isolated joint trauma (ie, isolated anterior cruciate ligament [ACL] rupture). Similarly, patients with more knee joint symptoms (ie, greater number of symptoms and increased severity of symptoms) may present with greater magnitudes of quadriceps inhibition. Recently, investigators15 have suggested that patients with more pain display less quadriceps strength, supporting this tenet. Given that effusion and pain often present simultaneously with joint injuries and diseases, such as ACL injury and osteoarthritis, examining both the isolated and cumulative effects of these sequelae appears warranted to determine if they influence the magnitude of muscle inhibition.Experimental joint-effusion and pain models are safe and effective experimental methods that allow for the isolated examination of their effects on muscle function. The effusion model, whereby sterile saline is injected directly into the knee joint capsule,7 produces a clinically relevant magnitude of the joint effusion that may be present with traumatic injury. Effusion is thought to activate group II afferents responding to stretch or pressure,1618 which in turn may facilitate group Ib interneurons and result in quadriceps AMI.5 The pain model involves injecting hypertonic saline into the infrapatellar fat pad to produce anteromedial knee pain similar to that described in patients with patellofemoral pain syndrome.19 Pain is considered to initiate AMI through activation of group III and IV afferents that act as nocioceptors to signal damage or potential damage to joint structures.1618 The firing of these afferents then may lead to facilitation of group Ib interneurons, the flexion reflex, or the gamma loop, ultimately resulting in quadriceps inhibition.20 Thus, these models allow us to create symptoms that are associated with knee injury and have the added benefit of providing a way to examine their effects in isolation.Therefore, the purpose of our study was to determine the effects of pain on quadriceps strength and activation and to learn if simultaneous pain and knee joint effusion would affect the magnitude of quadriceps dysfunction. We hypothesized that pain alone would result in quadriceps inhibition and that the magnitude of inhibition would be greater when effusion and pain were present simultaneously.  相似文献   

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即早基因c-fos与脑血管病及学习记忆   总被引:5,自引:1,他引:5  
即早基因c-fos是广泛存在于原核细胞和真核细胞的高度保守基因.在正常情况下,c-fos基因参与细胞生长、分化、信息传递、学习和记忆等生理过程,而在病理情况下c-fos基因表达及调控变化与多种疾病的发生和发展有关.C-fos在中枢神经系统的某些部位可有基础水平的表达,但表达很低,当受到如脑缺血、脑出血、痫性发作、应激等刺激后,其在数十分钟内做出反应,在对外界刺激-转录耦联的信忠传递过程中起着核内第三信使的重要作用.  相似文献   

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<正>人体解剖学与组织学胚胎学是高职护理及助产专业的学生接触最早而又重要的医学基础核心课程。鉴于目前高职护理及助产专业的教学内容多,课时少等难题,教与学的矛盾日益突出。因此,如何在有限的时间内既保证教学体系的完整性,又能解决时间与内容冲突的矛盾,从而使医学生对所学内容真正达到"必须、够用",是授课教师面临的严峻挑战。同时,顺应医学终身教育发展的需求,提高医学生自主学习的能力,  相似文献   

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This study examined how the development of aggressive/rule-breaking behaviors (9-17 years) is related to the development of overreactive and warm parenting, and explored gender differences in development and interrelations. Externalizing was assessed using combined mother/father reports of the Child Behavior Checklist (N = 516). Overreactivity was assessed using self-reports of the Parenting Scale; warmth was measured using self-reports of the Parenting Practices Questionnaire. All constructs were assessed three times across 6 years. The interrelated development of externalizing and parenting was examined by cohort-sequential multigroup latent growth models. Timing of effects was investigated using multigroup cross-lagged models. The results from latent growth models suggest that boys and girls change similarly in the extent to which they show externalizing behaviors, and indicate that mothers and fathers show somewhat different parenting toward boys than girls. No gender differences were found for interrelations between externalizing and parenting. Initial levels of aggression were related to changes in overreactivity and warmth, and vice versa. Changes in externalizing were related to changes in parenting. Cross-lagged models showed that relations between overreactivity and aggression/rule breaking were reciprocal. Together, results from this study show that adolescent externalizing and parenting affect each other in important ways, regardless of the gender of the child or the parent.  相似文献   

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OBJECTIVE: The purpose of this article is to review the role of behavioral research in disease prevention and control, with a particular emphasis on lifestyle- and behavior-related cancer and chronic disease risk factors--specifically, relationships among diet and nutrition and weight and physical activity with adult cancer, and tracking developmental origins of these health-promoting and health-compromising behaviors from childhood into adulthood. METHOD: After reviewing the background of the field of cancer prevention and control and establishing plausibility for the role of child health behavior in adult cancer risk, studies selected from the pediatric published literature are reviewed. Articles were retrieved, selected, and summarized to illustrate that results from separate but related fields of study are combinable to yield insights into the prevention and control of cancer and other chronic diseases in adulthood through the conduct of nonintervention and intervention research with children in clinical, public health, and other contexts. RESULTS: As illustrated by the evidence presented in this review, there are numerous reasons (biological, psychological, and social), opportunities (school and community, health care, and family settings), and approaches (nonintervention and intervention) to understand and impact behavior change in children's diet and nutrition and weight and physical activity. CONCLUSIONS: Further development and evaluation of behavioral science intervention protocols conducted with children are necessary to understand the efficacy of these approaches and their public health impact on proximal and distal cancer, cancer-related, and chronic disease outcomes before diffusion. It is clear that more attention should be paid to early life and early developmental phases in cancer prevention.  相似文献   

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To examine the hypothesis that foot-strike hemolysis alters vascular volumes and selected hematological properties is trained athletes, we have measured total blood volume (TBV), red cell volume (RCV) and plasma volume (PV) in cyclists (n?=?21) and runners (n?=?17) and compared them to those of untrained controls (n?=?20). TBV (ml?·?kg?1) was calculated as the sum of RCV (ml?·?kg?1) and PV (ml?·?kg?1) obtained using 51Cr and 125I-labelled albumin, respectively. Hematological assessment was carried out using a Coulter counter. Peak aerobic power (O2peak) was measured during progressive exercise to fatigue using both cycle and treadmill ergometry. RCV was 15% higher (P?n?=?12] and runners [35.3 (0.98); n=9] compared to the controls [30.7 (0.92); n?=?12]. Similar differences existed between the female cyclists [28.2 (2.1); n?=?9] and runners [28.4 (1.0); n?=?8] compared to the untrained controls [24.9 (1.4); n?=?8]. For the male athletes, PV was between 19% (cyclists) and 28% (runners) higher (P?P?V˙O2peak (ml?· kg?1?·?min?1) was higher (P?V˙O2peak for both cyclists and runners, no differences were found between the athletic groups within a gender. Since the vascular volumes were not different between cyclists and runners for either the males or females, foot-strike hemolysis would not appear to have an effect on that parameter. The significant correlations (P?V˙O2peak and RCV (r?=?0.64 and 0.64) and TBV (r?=?0.82 and 0.63) for the males and females, respectively, suggests a role for the vascular system in realizing a high aerobic power.  相似文献   

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3- and 4-dimethylaminobenzyl acrylates ( 3 and 4 ) and methacrylates ( 1 and 2 ) were prepared and their densities, IR and NMR spectra are recorded. In order to evaluate their reactivity towards benzoyl peroxide, the rate constants of the reaction of benzoyl peroxide with 3- and 4-dimethylaminobenzyl alcohols and 3- and 4-dimethylaminobenzyl acetates were determined. The reactivity of the esters prepared in this work appeared to be weaker than that of an N-aryl-N-alkylaminoalkyl methacrylate. The blocks of homopolymers of these esters and of their copolymers (mole ratio 1:1) with styrene and methyl methacrylate are crosslinked. Both homopolymers and copolymers of 1 and 3 are more stable in polar solvents and on heating than polymers of 2 and 4 . The copolymerization parameters of 1 and 2 with styrene are close to the copolymerization parameters of methyl methacrylate with styrene.  相似文献   

19.
Tobacco and alcohol and the risk of head and neck cancer   总被引:2,自引:0,他引:2  
Summary We carried out two case-control studies on the relative risk of head and neck cancer in association with tobacco and alcohol consumption. The first study carried out at the ENT Department of the University hospitals of Heidelberg and Giessen (FRG) comprised 200 male patients with squamous cell cancer of the head and neck and 800 control subjects matched for sex, age, and residential area (1:4 matching design). Of the tumour patients, 4.5% had never smoked, in contrast to 29.5% of the control group. The average tobacco and alcohol consumption of the patients was approximately twice as high as in the control subjects. The highest alcohol and tobacco consumption was observed in patients suffering from oropharyngeal cancer. Tobacco and alcohol increased the risk of head and neck cancer in a dose-dependent fashion and acted as independent risk factors. In heavy smokers (> 60 pack-years) a relative risk of 23.4 (alcohol adjusted) was calculated. Combined alcohol and tobacco consumption showed a synergistic effect. The risk ratio increased more in a multiplicative than in an additive manner. Oral and laryngeal cancer were associated with the highest tobacco-associated risk values. The highest ethanol-associated risk values were associated with oropharyngeal and laryngeal cancer. The second study was carried out at the ENT Department of the University of Heidelberg on 164 males with squamous cell carcinoma of the larynx and 656 control subjects matched for sex, age and residential area (1:4 matching design). Of the cases, 4.2% had never smoked, compared with 28.5% of the control subjects. The risk of laryngeal cancer by tobacco consumption was dose dependent, reaching a maximum value of 9.1 (adjusted for alcohol) for a consumption of more than 50 tobacco-years (TY). The relative risk of laryngeal cancer associated with alcohol intake was also dose dependent, reaching a value of 9.0 (adjusted for tobacco) for a mean daily consumption of more than 75 g alcohol. An analysis of subsite specific risks showed that heavy smokers (> 50 TY) carried a nearly ten times higher risk of supraglottic cancer than of glottic cancer. The risk of supraglottic cancer from alcohol consumption was also higher than that of glottic cancer.  相似文献   

20.
类赖氨酰氧化酶2(lysyl oxidase-like 2,LOXL2)是赖氨酰氧化酶(lysyl oxidase,LOX)基因家族的成员之一,其表达产物能促进胶原沉积.LOXL2的过表达能促进纤维化,并与肿瘤侵袭、转移及不良预后有关.目前大部分学者认为LOXL2是一种转移促进基因,也有实验支持其是一种肿瘤抑制基因.研究发现LOXL2可以通过激活Snail/Ecadherin通路或Src/FAK通路促进转移.LOXL2有望作为肿瘤生物标志物,用于预后判断,成为一个新的治疗靶点.  相似文献   

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