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21.
Purpose of Review8.5 to 50% of total joint arthroplasty (TJA) patients are reported to have preoperative malnutrition. The narrative review identifies the relationship between preoperative malnutrition for TJA patients and postoperative outcomes as well as the use of perioperative nutritional intervention to improve postoperative complications.Recent FindingsBiochemical/laboratory, anthropometric, and clinical measures have been widely used to identify preoperative nutritional deficiency. Specifically, serum albumin is the most prevalent used marker in TJA because it has been proven to be correlated with protein-energy malnutrition due to the surgical stress response. However, there remains a sustained incidence of preoperative malnutrition in total knee arthroplasty (TKA) and total hip arthroplasty (THA) patients due to a lack of agreement among the available nutritional screening tools and utilization of isolated laboratory, anthropometric, and clinical variables. Previous investigations have also suggested preoperative malnutrition to be a prognostic indicator of complications in general, cardiac, vascular, and orthopaedic surgery specialties.SummarySerum albumin, prealbumin, transferrin, and total lymphocyte count (TLC) can be used to identify at-risk patients. It is important to employ these markers in the preoperative setting because malnourished TKA and THA patients have shown to have worse postoperative outcomes including prolonged length, increased reoperation rates, increased infection rates, and increased mortality rates. Although benefits from high-protein and high-anti-inflammatory diets have been exhibited, additional research is needed to confirm the use of perioperative nutritional intervention as an appropriate treatment for preoperative TJA patients.  相似文献   
22.
The effects of clonidine, an indirectly-acting cholinergic antagonist, on 5 behaviors elicited by atropine (locomotion, rearing, sniffing, grooming and gnawing) were studied in rats. Clonidine did not alter the prevalence or magnitude of atropine-elicited locomotion and rearing. In contrast, clonidine suppressed the occurrence and degree of 3 stereotyped behaviors, namely, sniffing, grooming and gnawing. This selectivity of clonidine suggests differences in the neural pathways subserving the various stereotyped motor activities.  相似文献   
23.
众所周知,充血性心衰(CHF)为老年人较为常见的临床综合征之一.迄今关于左室收缩功能正常的CHF老人的相关临床特点远未清楚,本文特此进行了大样本分析. 对象与方法 4842例老年人,男1922例,女2920例,年龄66~103岁.尔后人均随访1年.旨在分析老年CHF年发病率,以及左室收缩功能正常的CHF老人相关临床特点. 结果随访期内,罹发1次或以上CHF者共425例次(8.8%/年).与未患发CHF老人相比,CHF老人平均年龄更大(79±6岁:77±5岁,P<0.001),女性居多,尤以高龄女性更多,如85岁以上的高龄女性CHF年发病率约较65~69岁女性高2倍(14%∶6.6%,P<0.001),AMI史、房颤、高血压、糖尿病、慢性阻塞型肺病、吸烟者均多,血脂及血肌酐亦高.多变量分析表明,罹患CHF与下列因素有关:老年尤其是高龄[年龄每增加5岁的患病奇数率(OR)女性1.2,男性1.1],AMI史(OR7.3),房颤者(OR3.0),糖尿病(OR2.1),肾功能不全(血肌酐≥1.5mg/dl的OR2.0),慢性阻塞肺病(仅老年女性的OR为1.8),以及左房、左室内径增大(内径每递增1cm的OR为2.0),和左室重量增加、左室收缩末期室壁张力增高、早期跨心房血流增多.超声心动图检测结果显示,CHF老人中,左室收缩功能正常者达55%,而仅有左室舒张功能不全,且左室收缩功能正常或轻度减退者高达80%.其中女性左室收缩功能正常者尤较男性多见(67%∶42%,P<0.001),表现为单纯左室舒张功能不良.而在左室收缩功能正常的CHF老人,常伴有左室内径较小、左室收缩末期室壁张力较低、左室重量较轻、左室收缩末期室壁厚度增加,而左室射血分数正常或仅轻度降低. 讨论以上结果提示,在老年人群中,CHF年发病率相对较高,且随年龄而增加,多数左室收缩功能正常,仅有左室舒张功能障碍,尤其是在高龄女性,亦即高龄女性左室舒张功能不全性CHF更为常见.对此,临床上更应拟出合理的防范措施,来正确诊治老年CHF综合征. (袁志敏摘)  相似文献   
24.
Increased C1q binding and arthritis in primary biliary cirrhosis.   总被引:3,自引:0,他引:3       下载免费PDF全文
Using the C1q binding assay, circulating immune complexes were detected in 31 of 50 (62%) patients with primary biliary cirrhosis and 17 of these had arthritis. This took the form of a seropositive inflammatory polyarthritis in 12 of 18 patients with C1q binding greater than or equal to 20%, whereas a milder seronegative arthritis associated with scleroderma and Raynaud's phenomenon was found in five of 13 patients with C1q binding < 20%. Only two of the 19 patients with normal binding had arthritis and this was of a mild and transient nature. There was a positive correlation between C1q binding and the serum concentrations of IgG and IgM. Results also supported the hypothesis that circulating immune complexes may be involved in the development of arthritis in patients with primary biliary cirrhosis.  相似文献   
25.
Hematopoietic chimerism was analyzed in serial bone marrow samples taken from 28 children following T-cell depleted unrelated donor bone marrow transplants (UD BMT) for acute lymphoblastic leukemia (ALL). Chimeric status was determined by polymerase chain reaction (PCR) of simple tandem repeat (STR) sequences (maximal sensitivity, 0.1%). At least two serial samples were examined in 23 patients. Of these, two had evidence of complete donor engraftment at all times and eight showed stable low level mixed chimerism (MC) (<1% recipient hematopoiesis). All 10 of these patients remain in remission with a minimum follow-up of 24 months. By contrast, 13 patients demonstrated a progressive return of recipient hematopoiesis. Five of these relapsed (4 to 9 months post BMT), one died of cytomegalovirus pneumonitis and seven remain in remission with a minimum follow-up of 24 months. Five children were excluded from serial analysis as two serial samples were not collected before either relapse (3) or graft rejection (2). We conclude that as with sibling transplants, ex vivo T depleted UD BMT in children with ALL is associated with a high incidence of MC. Stable donor engraftment and low level MC always correlated with continued remission. However, detection of a progressive return of recipient cells did not universally correlate with relapse, but highlighted those patients at greatest risk. Serial chimerism analysis by PCR of STRs provides a rapid and simple screening technique for the detection of relapse and the identification of patients with progressive MC who might benefit from detailed molecular analysis for minimal residual disease following matched volunteer UD BMT for childhood ALL.  相似文献   
26.
27.
D W Molloy  K Y Lee  D Jones  B Penner  R M Prewitt 《Chest》1985,88(3):432-435
The authors investigated acute cardiopulmonary effects of noradrenaline and isoproterenol infusion in a canine model of increased pulmonary vascular resistance (PVR) and decreased cardiac output (CO). In six anesthetized, ventilated dogs, autologous blood clots were injected over approximately two hours to increase right ventricular (RV) afterload and decrease CO. After CO had decreased 40 percent dogs were treated with noradrenaline or isoproterenol in alternate sequence. Both drugs increased stroke volume but only isoproterenol affected CO. Flow increased from 1.3 to 3.0 L X min-1 (p less than .01) with isoproterenol infusion. Corresponding to the increase in CO, RV filling pressure and PVR decreased, from 9 to 5 mm Hg, and from 36 to 16 mm Hg X L-1 X min (p less than .01) respectively. When a moderate decrease in CO complicates an acute increase in PVR, isoproterenol may be an excellent drug to treat the decrease in flow.  相似文献   
28.
29.
Breathing pattern and eye movement density during REM sleep in humans   总被引:3,自引:0,他引:3  
Changes in the density of eye movement during rapid eye movement (REM) sleep are associated with changes in ventilation and ventilatory response in animals. Recent data in patients with chronic obstructive pulmonary disease suggest that periods of frequent eye movements may be associated with hypoxemia during REM sleep. We have therefore investigated the association between eye movements and ventilation and ventilatory pattern in 10 normal men. Expired ventilation was measured using a pneumotachograph attached to a valved face mask with a dead space of 50 ml and incorporating a peripheral CO2 leak detector. Ventilation was reduced (p less than 0.02) in all stages of sleep compared with that during wakefulness, with no difference between the level of ventilation in each sleep stage (awake, 7.18 +/- 0.43 SEM; Stage 2, 6.47 +/- 0.43; Stage 3/4, 6.45 +/- 0.52; REM sleep, 6.55 +/- 0.47 L/min). During REM sleep, eye movements (EMs) were associated with rapid shallow breathing. Dividing REM into 20-s epochs with or without EMs, EMs were associated with a raised breathing frequency (no EMs, 14.4 +/- 0.4 breaths/min; EMs, 15.8 +/- 0.5 breaths/min; p = 0.01), reduced tidal volume (0.49 +/- 0.03 L; 0.41 +/- 0.03 L; p less than 0.01), and reduced minute ventilation (6.87 +/- 0.45 L; 6.27 +/- 0.51 L; p = 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
30.
Study ObjectivesTo examine longitudinal, bidirectional associations among behavioral sleep problems, internalizing and externalizing symptoms, and domains of health-related quality of life (HRQoL) from early childhood to adolescence in a population sample of Australian children.MethodData were drawn from the Longitudinal Study of Australian Children, a national prospective cohort study with 4983 children participating in the Kindergarten cohort. Data were collected when children were aged 4–5, 6–7, 8–9, 10–11, and 12–13 years. At each study wave, the primary parent (97% mothers) reported on behavioral child sleep problems, internalizing and externalizing symptoms, and HRQoL domains (psychosocial and physical). Cross-lagged structural equation models were used to evaluate bidirectional associations.ResultsAt nearly every age, behavioral sleep problems were associated with worse subsequent psychosocial and physical HRQoL. Despite bidirectional associations between mental health and HRQoL at many waves, HRQoL domains more strongly predicted later internalizing symptoms, while externalizing symptoms more strongly predicted later HRQoL. Many of the bidirectional associations among sleep, mental health, and HRQoL were found earlier in childhood.ConclusionsBehavioral sleep problems may forecast later HRQoL psychosocial and physical impairments. Attending to both sleep problems and HRQoL could prevent the progression of internalizing conditions, while a focus on externalizing concerns could prevent the worsening of these symptoms, sleep problems, and HRQoL, particularly during the transition to school.  相似文献   
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