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51.
This report described a 6-month-old boy who presented with miliary tuberculosis and severe CD8 deficiency, which is most likely secondary to miliary tuberculosis since his CD8 was back to normal 6 month after therapy and primary CD8 deficiency, (ZAP 70 defect) was ruled out. To our knowledge this is the first paediatric case reported with severe CD8 deficiency secondary to miliary TB.  相似文献   
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BACKGROUND: We evaluated the effect of autologous marrow stromal cells (MSCs) on neovascularization and blood flow in an animal model of chronic limb ischemia. METHODS: Chronic hind limb ischemia was created by ligating the left common iliac artery of male Lewis rats. Three weeks after ligation, 5.0 million LacZ+MSCs (n = 10) or culture medium (n = 10) were injected into the anteromedial muscle compartment of the left thigh. At 4 and 6 weeks after injection, half the animals (n = 5) from each group underwent femoral artery ultrasonic blood flow measurements of the ischemic and nonischemic limbs to obtain a flow ratio. The animals also underwent angiography and measurements of blood vessel density and arteriolar density. Qualitative histologic assessment of the limb muscles was performed. RESULTS: LacZ+MSCs were found to differentiate into endothelium (F VIII+), vascular smooth muscle (positive a-smooth muscle actin), skeletal muscle (positive desmin), and adipocytes. Ischemic hind limbs where MSCs were implanted had greater vascular density and arteriolar density than control limbs (p < 0.001). Femoral artery flow index (left femoral artery flow/right femoral artery flow) was 0.89 +/- 0.12 and 0.90 +/- 0.06 for rats injected with MSCs measured at 4- and 6-weeks, respectively, compared with 0.50 +/- 0.15 and 0.50 +/- 0.10 for the control rats (p < 0.001). Angiography demonstrated reconstitution of the left femoral artery in rats that received MSC implantation through pelvic and abdominal wall collateral formation. CONCLUSIONS: Local MSC implantation induces a neovascular response resulting in a significant increase in blood flow to the ischemic limb. Marrow stromal cells are also capable of spontaneously regenerating the various components of muscular tissues.  相似文献   
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Considerable progress has been made in the understanding of the risk factors for venous thromboembolism (VTE). The clinical applications of molecular techniques have allowed identification of important inherited, yet not uncommon, risk factors for VTE, such as mutations that cause Factor V Leiden and prothrombin G20210A. However, advances in our understanding have raised several questions regarding the need for, and duration of anticoagulation. At the end of the treatment period, low molecular weight heparins have become the drugs of choice and standard-of-care for VTE. In this review, cost effective diagnostic approaches for patients with suspected deep vein thrombosis, and recommended treatment options using evidence-based approaches, are described.  相似文献   
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A clinical skills laboratory or center is a facility in which students, physicians, nurses and other health care professionals learn clinical, communication and information technology skills to a specified level of competence prior to or coordinated with direct patient contact. The purpose of the clinical skill laboratory is to support the acquisition, maintenance and enhancement of the clinical skills of students in health care professions. Within this non-threatening environment, patient volunteers, simulated patients, mannequins and information technology are employed to provide hands-on learning experiences for the practice of the essential clinical skills. The skills laboratory helps to ensure that all students have necessary learning opportunities and appropriate assessment and feedback before approaching real patients. As more and more schools integrate skills laboratories into their curricula, it is important to review this new trend, to introduce the reader to its nature, factors that led to its development, advantages and problems related to its implementation. This review will also suggest some guidelines that may help in overcoming the implementation problems.  相似文献   
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The objective of the study is to examine the impact of accurate and inaccurate ‘split-time’ feedback upon a 10-mile time trial (TT) performance and to quantify power output into a practically meaningful unit of variation. Seven well-trained cyclists completed four randomised bouts of a 10-mile TT on a SRM™ cycle ergometer. TTs were performed with (1) accurate performance feedback, (2) without performance feedback, (3) and (4) false negative and false positive ‘split-time’ feedback showing performance 5% slower or 5% faster than actual performance. There were no significant differences in completion time, average power output, heart rate or blood lactate between the four feedback conditions. There were significantly lower (p < 0.001) average [(V)\dot]\textO2 \dot{V}{\text{O}}_{2} (ml min−1) and [(V)\dot]\textE \dot{V}{\text{E}}  (l min−1) scores in the false positive (3,485 ± 596; 119 ± 33) and accurate (3,471 ± 513; 117 ± 22) feedback conditions compared to the false negative (3,753 ± 410; 127 ± 27) and blind (3,772 ± 378; 124 ± 21) feedback conditions. Cyclists spent a greater amount of time in a ‘20 watt zone’ 10 W either side of average power in the negative feedback condition (fastest) than the accurate feedback (slowest) condition (39.3 vs. 32.2%, p < 0.05). There were no significant differences in the 10-mile TT performance time between accurate and inaccurate feedback conditions, despite significantly lower average [(V)\dot]\textO2 \dot{V}{\text{O}}_{2} and [(V)\dot]\textE \dot{V}{\text{E}} scores in the false positive and accurate feedback conditions. Additionally, cycling with a small variation in power output (10 W either side of average power) produced the fastest TT. Further psycho-physiological research should examine the mechanism(s) why lower [(V)\dot]\textO2 \dot{V}{\text{O}}_{2} and [(V)\dot]\textE \dot{V}{\text{E}} scores are observed when cycling in a false positive or accurate feedback condition compared to a false negative or blind feedback condition.  相似文献   
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Severe, medically unresponsive pulmonary hypertension (PHT) is considered to be a contraindication for orthotopic heart transplantation (OHT). Chronic left ventricular (LV) unloading using a left ventricular assist device (LVAD) might result in reversal of the elevated pulmonary vascular resistance (PVR), allowing successful OHT in such patients. In this study, we present a patient with end-stage ischemic cardiomyopathy and fixed, elevated PVR (7.1 Wood units) who underwent implantation of a Novacor LVAD (Baxter Healthcare Corp., Deerfield, IL, U.S.A.), with a subsequent reduction in PVR to 1.2 Wood units and successful OHT eleven months post-LVAD implantation. Three years after heart transplant, the patient still leads an active life with no right heart failure. In conclusion, OHT is not contraindicated in patients with end-stage heart failure and medically unresponsive PHT in the presence of elevated left atrial pressure. Left ventricular unloading should be considered in these patients to allow reversal of the elevated PVR before OHT.  相似文献   
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