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71.
To estimate the prevalence of avian influenza virus infection in Vietnam, surveillance was conducted in domestic and wild birds from households, live-bird markets, slaughtering sites, and bird sanctuaries in Vietnam between October 2010 and October 2012. Of the 4,550 samples collected, 226 influenza A virus isolates were obtained from domestic ducks, muscovy ducks, and chickens. Of these, 25 and 22 H5N1 highly pathogenic avian influenza viruses (HPAIVs) were isolated from apparently healthy domestic ducks in live-bird markets and slaughtering sites in northern and southern Vietnam, respectively. The HA genes of H5 viruses isolated from birds in northern Vietnam phylogenetically belonged to the genetic clade 2.3.2.1 and those in southern Vietnam belonged to the genetic clade 1.1. In addition, 39 H3, 12 H4, 1 H5, 93 H6, 2 H7, 18 H9, 3 H10, and 11 H11 viruses were isolated. Phylogenetic and antigenic analyses of the H6 and H9 viruses revealed that they were closely related to the isolates obtained from domestic poultry in China. Phylogenetic analyses of internal gene segments of these isolates revealed that these viruses were circulating in both domestic and wild birds in Asia and reassortment events had occurred frequently. Therefore, it will be important to continue the surveillance and strict controls over the movement and trade of poultry and poultry products in order to eradicate H5N1 HPAIV from Asia.  相似文献   
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73.
A retrospective chart review of 555 patients who received elective foot and ankle surgeries between 1995 and 2001 at 1 outpatient podiatric hospital clinic was performed to evaluate the efficacy of preoperative intravenous antibiotic use. Only those patients who were having elective foot or ankle surgery for the first time, were being followed up at the hospital's outpatient clinic, and had a nontraumatic cause for their surgery were included in this study. A wound was considered infected when purulent material from the wound sites was noted and an organism(s) was cultured. A wound complication was defined as a superficial dehiscence, edema, erythema, or stitch abscess. Three hundred six (55.1%) patients received a preoperative antibiotic and 249 (44.9%) patients did not. Of the 306 patients who received a preoperative antibiotic, 9 (1.6%) acquired a postoperative wound infection, whereas 8 (1.4%) of the 249 patients who did not receive preoperative antibiotics acquired a postoperative infection. A logistic regression model and chi square tests of association were used to determine if preoperative antibiotic use, age, gender, type of surgical procedure, operative time, tourniquet use, past medical history, and internal fixation were predictive of or associated with postoperative wound infection or complication. None of the study factors was predictive of postoperative wound infection or complication (P >.01). Preoperative antibiotic use was associated with surgical category and internal fixation use (P <.001) but not postoperative wound infection or complication (P >.01). The results suggest that prophylactic intravenous antibiotic use in routine elective foot and ankle surgery is not warranted.  相似文献   
74.
BACKGROUND AND PURPOSE: Previous studies have retrospectively reported the positive effects of percutaneous vertebroplasty. The purpose of our study was to evaluate prospectively the effects of vertebroplasty on mobility, analgesic use, pain, and SF-36 (short-form 36-item) scales for patients with painful vertebral compression fractures that are refractory to medical therapy. METHODS: We prospectively followed 167 patients who received 207 vertebroplasty treatment sessions for stabilization of 264 symptomatic vertebral compression fractures between August 1999 and January 2003. The average age of patients was 74.6 years (SD = 12.2 years), and 76% were women. Pre- and postprocedural measurements of pain, mobility, analgesic use, and SF-36 scales were compared at 1 month after the procedure and between 6 months and 3 years after the procedure with the SF-36 scales. RESULTS: Respective pre- and post-treatment pain scores were 8.71 (SE = 0.1) and 2.77 (SE = 0.18; P < .00001). Respective pre- and post-treatment analgesic use scores were 2.93 (SE = 0.9) and 1.64 (SE = 0.09; P < .00001). Respective pre- and post-treatment activity levels were 2.66 (SE = 0.1) and 1.64 (SE = 0.11; P < .00001). There was a statistically significant improvement on nine of 10 SF-36 scales (P < .001) after 1 month and on eight of 10 SF-36 scales (P < .02) at long-term follow-up. CONCLUSION: Percutaneous vertebroplasty offers statistically significant benefits in decreasing pain, decreasing use of analgesics, and increasing mobility in appropriately selected patients. Percutaneous vertebroplasty also offers a statistically significant benefit in most SF-36 scales at both short- and long-term follow-up.  相似文献   
75.
The effect of piroxicam on rat polymorphonuclear leucocytes (PMN) has been studiedin vitro andin vivo after the induction of two acute, non specific inflammatory reactions (pleurisies induced by calcium pyrophosphate crystals (CaPP) or isologous serum).An inhibition of chemotaxis by piroxicam has been demonstrated by two techniques, the filter and agarose assaysin vivo andin vitro. An inhibition of random cell migration has been observed only at the higher drug concentration using agarose assay with CaPP-elicited cells.Piroxicam also inhibited superoxide anion generation and O2 consumption of CaPP- and serum-elicited cells.These findings suggest that piroxicam may have a direct effect on PMN responses and that this activity could, at least in part, contribute to its anti-inflammatory properties.  相似文献   
76.
The purpose of this study was to compare the capability of interference and rectified electromyography (EMG) to detect changes in the beta (13–30‐HZ ) and Piper (30–60‐HZ ) bands when voluntary force is increased. Twenty adults exerted a constant force abduction of the index finger at 15% and 50% of maximum. The common oscillations at various frequency bands (0–500 HZ ) were estimated from the first dorsal interosseous muscle using cross wavelets of interference and rectified EMG. For the interference EMG signals, normalized power significantly (P < 0.01) increased with force in the beta (9.0 ± 0.9 vs. 15.5 ± 2.1%) and Piper (13.6 ± 0.9 vs. 21 ± 1.7%) bands. For rectified EMG signals, however, the beta and Piper bands remained unchanged (P > 0.4). Although rectified EMG is used in many clinical studies to identify changes in the oscillatory drive to the muscle, our findings suggest that only interference EMG can accurately capture the increase in oscillatory drive from 13 to 60 HZ with voluntary force. Muscle Nerve, 2010  相似文献   
77.
78.
Abstract

Background/Objective: To determine factors associated with falls among a sample of ambulatory individuals with incomplete spinal cord injury (SCI).

Study Design: Cross-sectional mail survey.

Methods: A survey instrument of participant characteristics and fall-related variables was developed using relevant items from existing measures and was mailed to 221 individuals with incomplete SCI, who were identified from records of a large specialty hospital in the southeastern United States. Of the 221 prospective participants, 119 completed the questionnaire (54%). Multivariable logistic regression models were used to determine factors that were independently associated with having had a fall in the past year.

Results: After adjusting for covariates, having fallen in the past year was significantly (P < 0.05) associated with greater numbers of medical conditions (odds ratio [OR] = 1.3; 95% confidence interval [Cl] = 1.0-1.7), having arthritis (OR = 3.4, 95% Cl = 1.2-9.6), experiencing dizziness (OR = 5.6, 95% Cl = 1.1-27.7), greater numbers of days with poor physical health (OR = 1.1; 95% Cl = 1.0-1.3), and the restriction of community activities because of fear of falling (OR = 1.5, 95% Cl = 1.1-2.1). The multivariable models also showed that the odds of having fallen were significantly lower among those with better current perceived physical health (OR = 0.5; 95% Cl = 0.3-0.9), those with better perceived health compared to a year ago (OR = 0.4; 95% Cl = 0.2-0.8), individuals who exercised more frequently (OR = 0.2; 95% Cl = 0.1-0.7), and those who used a walker (OR = 0.3; 95% CI = 0.1-0.9).

Conclusions: Results suggest that interventions that address exercise frequency, walker use, and dizziness have promise for reducing falls for individuals with incomplete SCI.  相似文献   
79.
Abstract

Background/Objective: To determine whether 9 weeks of locomotor training (LT) results in changes in muscle strength and alterations in muscle size and activation after chronic incomplete spinal cord injury (SCI). Study Design: Longitudinal prospective case series.

Methods: Five individuals with chronic incomplete SCI completed 9 weeks of LT. Peak isometric torque, torque developed within the initial 200 milliseconds of contraction (Torque200), average rate of torque development (ARTD), and voluntary activation deficits were determined using isokinetic dynamometry for the knee-extensor (KE) and plantar-flexor (PF) muscle groups before and after LT. Maximum muscle crosssectional area (CSA) was measured prior to and after LT.

Results: Locomotor training resulted in improved peak torque production in all participants, with the largest increases in the more-involved PF (43.9% ± 20.0%), followed by the more-involved KE (21.1% ± 12.3%). Even larger improvements were realized in Torque200 and ARTD (indices of explosive torque), after LT. In particular, the largest improvements were realized in the Torque200 measures of the PF muscle group. Improvements in torque production were associated with enhanced voluntary activation in both the KE and ankle PF muscles and an increase in the maximal CSA of the ankle PF muscles.

Conclusion: Nine weeks of LT resulted in positive alterations in the KE and PF muscle groups that included an increase in muscle size, improved voluntary activation, and an improved ability to generate both peak and explosive torque about the knee and ankle joints.  相似文献   
80.
Abstract

Background/Objective: Children with spinal cord injury (SCI) are at risk for musculoskeletal and cardiovascular complications. Stationary cycling using functional electrical stimulation (FES) or passive motion has been suggested to address these complications. The purpose of this case series is to report the outcomes of a 6-month at-home cycling program for 4 children with SCI.

Methods: Two children cycled with FES and 2 cycled passively at home for 1 hour, 3 times per week.

Outcome Measures: Data collected included bone mineral density of the left femoral neck, distal femur, and proximaltibia; quadriceps and hamstring muscle volume; stimulated quadriceps and hamstring muscle strength; a fasting lipid profile; and heart rate and oxygen consumption during incremental upper extremity ergometry testing.

Results: The 2 children cycling with FES and 1 child cycling passively exhibited improved bone mineral density, muscle volume, stimulated quadriceps strength, and lower resting heart rate. For the second child cycling passively, few changes were realized. Overall, the lipid results were inconsistent, with some positive and some negative changes seen.

Conclusions: This case series suggests that cycling with or without FES may have positive health benefits and was a practical home exercise option for these children with SCI.  相似文献   
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