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991.
1992年,当WHO东南亚地区委员会作出了要求改变本地区当时普遍存在的卫生人力资源同卫生服务需求不相适的状况的决定以后,卫生人力不平衡和同卫生服务相关联的问题已得到了稳步的改善。这里所说的不平衡是指卫生人力数量、分布和同技能相关的问题,而关联性则是指在校教育和同专业能力相匹配的卫生人员继续教育项目与设施的性质和合适性。综观东南亚各国卫生人力资源的发展,为进一步改善卫生人力数量、结构和分布的不合理性,提高医学教育的质量,作者认为在实践中应注意以下四个问题。  1、重定医学教育的方向。对医学教育和护理教育项…  相似文献   
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Objective: To determine patient, clinician, and practice setting characteristics associated with physical therapists' treatment choices in patients with knee, lumbar, and cervical impairments.Design: Secondary analysis of data from the Focus on Therapeutic Outcomes (FOTO) database.Setting: Data from 132 physical therapy practices owned by five United States outpatient rehabilitation companies.Patients: The database contained information on 5,061 patients with knee, lumbar, or cervical impairments seen in these practices in 1993 and 1994 and agreeing to participate in data collection. Our sample consisted of 2,491 patients, treated by 462 physical therapists, who had complete data on the variables of interest.Results: Physical therapists' treatment choices relied on factors other than the patient's clinical status when the impairment was likely to result in professional uncertainty as to diagnosis and consequences of treatments. For patients with spinal impairments, the clinical status of the patient was associated only with the choice of endurance exercises and modalities. Patient's clinical status was associated with every treatment type in patients with knee impairments. Educational level of the physical therapist, patient load, and payer were associated with a variety of treatment choices across the impairment types.Conclusion: In conditions of professional uncertainty, physical therapy practice may be influenced by many idiosyncratic factors.  相似文献   
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The cast immobilization of a fractured limb results in a loss of bone mass; however, the long-term implications of that effect with regard to bone mineral status, particularly in other skeletal sites, are less known. The purpose of this study was to describe changes in bone mass in different skeletal sites triggered by Colles' fracture. The case is unique regarding the existence of baseline measurements taken just a few days before the fracture on all measurable skeletal sites, including the fractured radius. Therefore, it was also possible to determine whether the injury caused long-term bone loss in the affected and unaffected skeletal sites. The patient was a healthy, premenopausal Caucasian woman, in her late forties, who fractured her nondominant wrist as a result of low-impact fall on ice. The arm and the metacarpals were immobilized to the elbow for 5 wk. Bone mass measurements were performed with DPX-MD densitometer (Lunar Corp. Madison, WI) at baseline and 5, 10, 13, 21, and 52 wk postinjury. At the 5-wk measurement (on plaster removal) there was a notable increase in bone mineral density (BMD) and bone mineral content (BMC) in all sites of ulna and radius of the injured forearm (from 10 to 73%), followed by the apparent decline to or below the baseline at 10, 13, 21 and 52 wk of follow-up. Other skeletal sites were measured at 10 wk when a substantial decrease in BMD and BMC in some of the hip regions and lumbar spine was noticed; most notably in L3-L4, Ward's triangle, and femoral neck (from 2 to 8%) and remained such after 1 yr. Although this patient had a normal bone mineral status and no osteopenia detected before fracture, the trauma of radial fracture caused long-standing bone loss in fracture-prone areas-hip and spine. Because about 70% of bone strength is explained by its mineral density, the patient might be at increased risk for fracture later in life. The changes in bone mass after injury should be monitored and interpreted carefully, and more elaborate treatment of patients presenting with wrist fractures are needed to prevent any potential risk for later osteoporotic fractures in spine and hip and possible refracture of the injured extremity.  相似文献   
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The primary restraint preventing humeral head translation is the capsuloligamentous system. Muscle forces can also decrease translation; however, the timing and magnitude of muscle response has not been previously reported. Fine wire electromyographic analysis of the biceps long head, anterior deltoid, pectoralis major, latissimus dorsi, and rotator cuff muscles was performed after an anterior translation force was applied to 15 normal shoulders. The reflex response time (time to 5% maximal muscle test), the protection response time (time to 20% maximal muscle test), the duration of the protection response, and the magnitude of the protection response were calculated. The shoulder reaction data showed 2 consistent patterns. Activation of the anteriorly located muscles preceded the posteriorly located muscles, and the rotator cuff muscles fired with greater magnitude than the more peripherally located muscles.  相似文献   
998.
By using perfusions and bolus administration, coupled with postembedding immunocytochemical procedures, we have identified the structures involved in the transport of derivatized orosomucoid (α1-acidic glycoprotein) across the continuous microvascular endothelium of the murine myocardium. Our findings indicate that: (i) monomeric orosomucoid binds to the luminal surface of the endothelium; (ii) it is restricted to caveolae during its transport across the endothelium; (iii) it is detected in the perivascular spaces at early time points (by 1 min) and in larger quantities at later time points (>5 min) from the beginning of its perfusion or its intravascular administration; (iv) no orosomucoid molecules are found in the intercellular junctions or at the abluminal exits of interendothelial spaces; and (v) the vesicular transport of orosomucoid is strongly inhibited by N-ethylmaleimide (>80%). Because, by size and shape, the orosomucoid qualifies as a preferential probe for the postulated small pore system, our results are discussed in relation to the pore theory of capillary permeability.  相似文献   
999.
The present study investigated developmental changes in postural adjustments during preschool age. Postural responses during sitting on a moveable platform were assessed in 21 healthy children aged 1% to 4% years. Multiple surface EMGstof neck, trunk, and leg muscles were recorded during forward and backward translations. Comparable data were available for 11 infants seen three times between the ages of 5 and 10 months. The data revealed the existence of a transient period between the ages of 9 to 10 months and 21/2 to 3 years, during which perturbations in a sitting position are accompanied by high activity in the direction-specific agonist muscles and in the antagonist muscles. After this period, agonist activity became more variable, particularly so during backward translations, and antagonist activity disappeared. These changes could be attributed to biomechanical factors and to maturation of the nervous system.  相似文献   
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