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761.
Many coaches in Big Ten schools still burden their athletes with a protein-rich precompetition meal. This survey indicates that coaches need—and want—more and better information about nutrition.  相似文献   
762.
BACKGROUND AND PURPOSE: MP4 (Hemospan) is a Hb-based oxygen therapeutic agent, based on polyethylene-glycol (PEG) conjugation to Hb, undergoing clinical trials as an oxygen carrier. This study describes the functional interaction between MP4 and carbon monoxide (CO), as a CO delivery agent, and the effects of CO-MP4 on myocardial infarct size following ischaemia and reperfusion in rats. EXPERIMENTAL APPROACH: Kinetic measurements of CO-MP4 binding were used to evaluate the effects of PEG modification on Hb subunit structure/function and to calculate CO-MP4 equilibrium constants. CO transport by CO-MP4 was shown by ligand (O2/CO) partitioning between MP4 and red blood cell (RBC)-Hb. Pharmacological effects of CO-MP4 were studied on myocardial infarction in rats. KEY RESULTS: CO binding kinetics show primary structural/functional effects on beta chains in MP4, with alpha chains maintaining the ability to undergo tertiary conformational transition. CO confers long-term, room-temperature stability and is able to rapidly re-equilibrate between MP4 and RBCs. In a rat model of myocardial infarct, in contrast to oxy-MP4, CO-MP4 reduced infarct size when administered prior to the induction of ischaemia. CONCLUSIONS AND IMPLICATIONS: MP4 PEGylation chemistry modifies the individual function of Hb subunits, but results in an overall CO equilibrium constant similar to that for unmodified Hb. CO-MP4 is able to deliver CO to the circulation and reduces ischaemia/reperfusion injury in rats, providing the first evidence for this drug as a CO therapeutic agent.  相似文献   
763.
目的:观察血管内皮生长因子对佐剂性关节炎滑膜细胞质金属蛋白酶3及质金属蛋白酶9表达的影响,并探讨其意义。方法:实验于2006-02/12在桂林医学院实验中心完成。①实验材料:清洁级8周龄雄性Wistar大鼠6只,血管内皮生长因子为Peprotech EC LTD公司产品,基质金属蛋白酶3(扩增369bp)上游引物、下游引物,基质金属蛋白酶9(扩增405bp)上游引物、下游引物均购自晶美公司。②实验干预:先用弗氏完全佐剂造Wistar大鼠模型;造模20d后取Wistar大鼠右后足滑膜细胞进行原代培养。③实验分组:实验分为血管内皮生长因子组:取P2代细胞接种于6孔培养板,分别加入终浓度为5,25,50μg/L血管内皮生长因子;对照组:不加血管内皮生长因子。④实验评估:取病理切片观察滑膜细胞形态学改变;采用半定量反转录聚合酶链反应检测Wistar大鼠佐剂性关节炎滑膜细胞基质金属蛋白酶3及基质金属蛋白酶9的m-RNA表达。结果:①培养细胞的形态学观察:原代培养14d滑膜细胞从组织块边缘逸出,21d密集生长开始传代;传代细胞48h可明显分辨出树突样细胞、巨噬细胞样细胞和成纤维细胞样细胞;传至21代,细胞生长及特性稳定。②病理切片:滑膜组织有中性粒细胞、单核细胞、淋巴细胞浸润,滑膜细胞增生、排列紊乱,纤维素渗出,胶原纤维沉着,纤维素样坏死,呈滑膜炎表现。③基质金属蛋白酶3、基质金属蛋白酶9的mRNA表达:对照组基质金属蛋白酶3mRNA表达相对灰度值与血管内皮生长因子终浓度5,25,50μg/L组比较,差异有显著性意义(0.32±0.03,0.77±0.06,1.12±0.12,1.59±0.02,P<0.05);对照组基质金属蛋白酶9mRNA表达相对灰度值与血管内皮生长因子终浓度5,25,50μg/L组比较,差异有显著性意义(0.47±0.07,0.50±0.10,0.91±0.10,1.31±0.06,P<0.05);基质金属蛋白酶3和基质金属蛋白酶9mRNA表达随血管内皮生长因子浓度的加大表达增加。结论:血管内皮生长因子以剂量递增的方式对体外培养的佐剂性关节炎滑膜细胞基质金属蛋白酶3及基质金属蛋白酶9的表达有促进作用。  相似文献   
764.
The National Marrow Donor Program   总被引:2,自引:0,他引:2  
As the number of successful marrow transplants has increased, the lack of HLA-identical sibling donors for 60 to 70 percent of transplant candidates has become a serious problem. Pilot studies established that marrow transplantation between phenotypically HLA-identical, unrelated individuals can be accomplished successfully. Therefore, the National Marrow Donor Program was established to develop a large file of volunteer marrow donors and to serve as a center for the coordination of the donor search and donor-recipient matching processes. By November 1991, 63 months after the program was established, 457,205 potential marrow donors typed for HLA-A and -B antigens had agreed to be listed in the marrow donor registry. A donor search had been initiated for 8481 patients. At least one potential donor matched for at least three of the four HLA-A and -B antigens was located for 99.8 percent of patients. Among the 3156 searches that were completed, 940 (29.8%) resulted in a transplant. The median time in which to locate a matched donor, complete all predonation evaluations, and obtain donor consent was 208 days. The most common diagnosis in patients who underwent transplantation was chronic myelogenous leukemia (42.0%). When this analysis was completed in November 1991, the National Marrow Donor Program was operating a national network of 99 donor centers and 53 transplant centers. The donor file was increasing rapidly, and a follow- up system was in place to determine the effects of donation on the donors and the outcome in the patients who underwent transplantation. This national network of donor and transplant centers exists and is now facilitating unrelated-donor marrow transplants. The National Marrow Donor Program made it possible to locate donors for many patients in need of a transplant and helped to determine the role of unrelated- donor marrow transplants in the treatment of many diseases.  相似文献   
765.
Reduction of digitoxin binding to plasma proteins after heparin has been reported. Our aim was to determine whether this reduction is an in vivo effect or occurs only after blood collection as a result of heparin-induced lipolysis that increases levels of nonesterified fatty acids in vitro. The effect of heparin on digitoxin protein binding was studied in 10 patients undergoing hemodialysis receiving digitoxin maintenance therapy. Digitoxin free fraction increased after heparin, from 2.5% +/- 0.7% to 4.4% +/- 1.1%, but after inhibition of in vitro lipolysis with diethyl p-nitrophenyl phosphate (2mM), a potent lipase inhibitor, there was no increase in the free fraction (2.3% +/- 0.4% before heparin and 2.4% +/- 0.5% after heparin). Digitoxin salivary levels were also unchanged (0.41 +/- 0.08 ng/ml before heparin and 0.41 +/- 0.08 ng/ml after heparin [n = 8]). These data indicate that the binding of digitoxin to plasma proteins in vivo is not altered by heparin. The reduced binding reported elsewhere was a result of heparin-induced in vitro lipolysis.  相似文献   
766.
Englert  H.  Richards  BL.  Angelides  S.  Kumar  V.  Spencer  D.  Howe  G.  Manolios  N. 《Annals of nuclear medicine》2021,35(10):1157-1166
Annals of Nuclear Medicine - To evaluate the role of 99mTc-labelled glucosamine [99mTc-ECDG] as a clinical biomarker for the early detection of interstitial lung disease (ILD) in systemic sclerosis...  相似文献   
767.
768.
The purpose of this study was to develop a new device to assess balance in two planes and then to provide training paradigms for balance abnormalities. Based on the principal of a Biomechanical Ankle Platform System? (BAPS) board, the device is different than other devices that are on the market today in that this device allows assessment of balance during body sway movement in the forward\back and side-to-side directions. Like the BAPS board, individuals balance themselves on the board with a pivot in the centre. However, unlike the BAPS board, a variable viscosity magnetic fluid is used to vary the dampening on the board such that the board can be fixed in the forward\back or side-to-side plane. It can also be allowed to move either freely in both planes or with some dampening in any direction. This device offers a major improvement over other balance measuring devices in that it allows movement in multiple planes. It also allows for rapid alterations of movement in any plane to test an individual's ability to maintain their balance against a challenge.  相似文献   
769.

Context:

Epicondylalgia is a common condition involving pain-generating structures such as tendon, neural, and chondral tissue. The current noninvasive reference standard for identifying chondral lesions is magnetic resonance imaging. Musculoskeletal ultrasound (MUS) may be an inexpensive and effective alternative.

Objective:

To determine the intrarater reliability and validity of MUS for identifying humeroradial joint (HRJ) chondral lesions.

Design:

Cross-sectional study.

Setting:

Clinical anatomy research laboratory.

Patients or Other Participants:

Twenty-eight embalmed cadavers (14 women, 14 men; mean age = 79.5 ± 8.5 years).

Main Outcome Measure(s):

An athletic trainer performed MUS evaluation of each anterior and distal-posterior capitellum and radial head to identify chondral lesions. The reference standard was identification of chondral lesions by gross macroscopic examination. Intrarater reliability for reproducing an image was calculated using the intraclass correlation coefficient (3,k) for measurements of the articular surface using 2 images. Intrarater reliability to evaluate a single image was calculated using the Cohen κ for agreement as to the presence of chondral lesions. Validity was calculated using the agreement of MUS images and gross macroscopic examination.

Results:

Intrarater reliability was 0.88 (95% confidence interval = 0.77, 0.94) for reproducing an image and 0.93 (95% confidence interval = 0.80, 1.06) for evaluating a single image. Identifying chondral lesions on all HRJ surfaces with MUS demonstrated sensitivity = 0.93, specificity = 0.28, positive predictive value = 0.58, negative predictive value = 0.77, positive likelihood ratio = 1.28, and negative likelihood ratio = 0.27.

Conclusions:

Musculoskeletal ultrasound is a reliable and sensitive tool for a clinician with relatively little experience and training to rule out HRJ chondral lesions. These results may assist with clinical assessment and decision making in patients with lateral epicondylalgia to rule out HRJ chondral lesions.Key Words: elbow joint, articular cartilage, reliability, assessment

Key Points

  • When used by a clinician with limited experience and training, musculoskeletal ultrasound imaging was reliable and sensitive for ruling out humeroradial joint chondral lesions.
  • More study is needed, but musculoskeletal ultrasound imaging may be helpful in assessing and managing patients with lateral epicondylalgia.
The elbow is one of the joints most commonly affected by articular cartilage degeneration and loosening of chondral fragments.1 Chondral lesions and articular cartilage degeneration primarily occur in the lateral compartment of the elbow within the humeroradial joint (HRJ).24 Although HRJ chondral lesions can occur secondary to acute trauma, they may be present in the absence of trauma.5Lateral elbow conditions occur in a variety of sports,6 and up to 50% of overhead athletes experience elbow injuries.7 In overhead athletes, valgus extension overload is observed during the late cocking phase of throwing.8 This results in significant compression forces of up to 500 N on the HRJ, which can lead to chondral lesions.8,9 In the general population, HRJ chondral lesions have been demonstrated in 51% to 81% of patients with chronic lateral elbow pain.5,10 Articular cartilage lesions are easily misdiagnosed as tendinopathy of the wrist extensors because they have similar clinical presentations.5,11 Symptoms include insidious onset of lateral elbow pain, pain with resisted wrist extension, and failure to respond to conservative treatment.5 To our knowledge, no validated clinical examination exists for the differential diagnosis of HRJ chondral lesions from lateral epicondylopathy.The current noninvasive reference standard for the diagnosis of chondral lesions is magnetic resonance imaging.12 Musculoskeletal ultrasound (MUS) is a safe and inexpensive alternative imaging technique that is effective in showing articular cartilage abnormalities and loose bodies,1,13 although most research to date has focused on the hip, knee, and hand.12,14,15 At the elbow joint, several authors16,17 have demonstrated validity for detecting loose bodies with MUS. However, we know of no authors who have evaluated the validity of MUS for identifying HRJ chondral lesions.Traditionally, radiologists perform and interpret MUS examinations.18 More recently, the use of MUS has expanded to sports medicine clinicians, physiotherapists, and athletic trainers.1821 As the use of MUS extends into clinics and athletic training facilities, the reliability of clinicians'' examinations with MUS must be expanded because the technique is user dependent.22 Furthermore, it is critical to establish whether the performance of such clinicians is equal to that of expert technicians. However, before interrater reliability can be evaluated, MUS must be validated for identifying HRJ chondral lesions to determine its usefulness.Although our purpose was not to establish the reliability of clinicians'' use of MUS, we know that for a tool to be valid, it must be reliable.23 Therefore, the purposes of our study were to (1) investigate the intrarater reliability and validity of an athletic trainer to identify chondral lesions in the HRJ using MUS and (2) determine the prevalence of HRJ chondral lesions in elderly specimens. We hypothesized that an athletic trainer would be reliable at reproducing and evaluating MUS images and accurate in identifying chondral lesions at the HRJ using MUS.  相似文献   
770.
Dual-energy X-ray absorptiometry (DXA) measurements were analyzed using two versions of software (Hologic V8.1a and V8.21) to compare the short- and long-term precisions of the measurements. Software V8.21 was designed by the manufacturer to better address magnification effects on estimations of soft tissue lean mass. Twenty weight-stable, obese postmenopausal Caucasian women aged 40-70 yr participated in the study. Total and regional body composition measurements were obtained at baseline and after 3 mo, using a fan beam Hologic QDR 4500A absorptiometer. For the estimation of precision, duplicate scans obtained on the same day for nine women were analyzed using both versions of the software. The correlations between duplicate scans ranged from 0.886 to 0.998 and were similar between software versions. The CVs for fat and lean weights and bone mineral content (BMC) were 1.2%, 1.1%, and 1.7%, respectively, for software V8.21 compared to 1.3%, 1.3%, and 2.1%, respectively, for V8.1a. Systematic differences were found between software versions with higher values for fat and lean weights for software version V8.21. The 3-mo, long-term reproducibility of body composition estimates from DXA was only slightly less than short-term reproducibility for both software versions (coefficient of variation [CV] range from 1.3% for BMC weight to 11.0% for arm fat). Software V8.21 yielded smaller percentage mean differences between scale and DXA-estimated weights (-2.4% and -7.2% at baseline and -2.9% and -7.6% at 3 mo, respectively) and higher fat and lean weights (49.12 and 47.1 kg and 49.6 and 44.6 kg, respectively) than V8.1a. Reproducibility of all variables was comparable between software versions.  相似文献   
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