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51.

Background  

Measuring the orientation of acetabular cup after total hip arthroplasty is important for prognosis. The verification of these measurement methods will be easier and more feasible if we can synthesize prosthesis radiographs in each simulated condition. One reported method used an expensive mechanical device with an indeterminable precision. We thus develop a program, THR Simulator, to directly synthesize digital radiographs of prostheses for further analysis.  相似文献   
52.
C C Pao  W L Yang  C C Huang  J L Hsu  S S Lin  R Ken  Y Chao  C F Sun  Y F Liaw  J Y Lin 《Nephron》1987,46(2):155-160
Possible presence of hepatitis type B virus (HBV) was assessed in 239 end-stage renal failure patients who were receiving long-term maintenance hemodialysis (average 30.8 months; duration: 1-94 months), and who had not shown any other symptom of HBV infection. Their HBV serological markers, including HBV DNA, were evaluated together with those of normal control individuals. HBV surface antigen (HBsAg) was detected in 42 of the 239 dialysis patients, 15 of whom also positive for HBV DNA (mean +/- SD = 56.2 +/- 23.7 pg/100 microliters of serum). HBV DNA was also found in 22 of the 197 (11.2%) dialysis patients who were negative for HBsAg, with an average of 36.2 +/- 19.0 pg/100 microliters of serum. This rate of detecting HBV DNA in HBV seronegative dialysis individuals was significantly higher than the rate of 1.83% found among healthy HBsAg(-) individuals. Among these 22 dialysis patients who were HBsAg(-) but HBV DNA(+), 15 were found to possess antibodies against HBsAg (anti-HBs) and/or antibody against HBV e antigen (anti-HBe). These data suggested that the absence of serum HBV antigen or the presence of antibodies against HBV markers might not be sufficient to identify possible HBV infection in immunocompromised hosts such as hemodialysis patients.  相似文献   
53.
Hepatoma with cardiac metastasis is difficult to diagnose antemortem. Herein we describe five cases of hepatoma with intracardiac metastasis detected with two-dimensional echocardiography (2DE). The clinical presentations include cardiac murmur, syncope, and chest pain. The 2DE demonstrated a right atrial (RA) mass in each case and the presence of tumor echoes in the inferior vena cava connecting with the RA mass in four. In three cases the cardiac tumor was removed, whereas the other two patients agreed only to liver biopsy, which confirmed the diagnosis. This paper emphasizes the practical utility of 2DE for early detection of intracardiac hepatoma and also describes the clinicopathologic correlation of such a disease entity.  相似文献   
54.
Zhang B  Tao F  Liaw WJ  Bredt DS  Johns RA  Tao YX 《Pain》2003,106(1-2):187-196
PSD-93/chapsin-110 is a neuronal PDZ domain-containing protein that binds to and clusters the N-methyl-D-aspartate receptor (NMDAR) at synapses in the central nervous system. It also assembles a specific set of signaling proteins around the NMDAR and mediates downstream signaling by the NMDAR. Thus, PSD-93/chapsin-110 might be involved in many physiological and pathophysiological actions triggered via the activation of the NMDAR. In the current study, we report that abundant PSD-93/chapsin-110 protein was detected in rat spinal cord, particularly in the superficial dorsal horn. The rats injected intrathecally with PSD-93/chapsin-110 antisense oligodeoxynucleotide every 24 h for 4 days displayed not only a remarkable decrease in spinal cord PSD-93/chapsin-110 expression but also a significant reduction in the paw withdrawal responses to thermal and mechanical stimuli during complete Freund's adjuvant-induced inflammatory pain and peripheral nerve injury-induced neuropathic pain. In contrast, the rats injected intrathecally with PSD-93/chapsin-110 missense oligodeoxynucleotide did not exhibit these changes. We also found that pretreatment with PSD-93/chapsin-110 antisense oligodeoxynucleotide did not change the locomotor activity or the responses to acute noxious thermal and mechanical stimuli in intact rats. The present results indicate that the deficiency of spinal cord PSD-93/chapsin-110 protein significantly attenuates thermal and mechanical hyperalgesia in complete Freund's adjuvant- or peripheral nerve injury-induced chronic pain. This suggests that spinal cord PSD-93/chapsin-110 might be involved in the central mechanism of chronic pain. Our work might provide a new target for the therapy of chronic pain.  相似文献   
55.
OBJECTIVE: To evaluate if resistive inspiratory muscle training (RIMT) can improve lung function in patients with complete tetraplegia within half a year after trauma. DESIGN: A prospective study. The experimental patients received training with a Diemolding Healthcare Division inspiratory muscle trainer for 15 to 20 minutes per session, twice per day, 7 days a week for 6 weeks. SETTING: Hospital-based rehabilitation units. PATIENTS: Twenty patients who were in their first 6 months of complete cervical cord injury were randomly enrolled into RIMT (10 patients) and control (10 patients) groups. MAIN OUTCOME MEASURE: Spirometry, lung volume test, maximal inspiratory pressure, maximal expiratory pressure, and modified Borg scale measurements at rest were performed before training and at the end of 6 weeks of training. RESULTS: Most of the pulmonary parameters showed statistically significant improvements within the RIMT and control groups, but the improvements were greater in the RIMT group. In addition, the improvements in total lung capacity, total lung capacity predicted percentage, vital capacity, minute ventilation, forced expiratory volume in 1 second predicted percentage, and the resting Borg scale in the RIMT group showed significantly greater improvement. CONCLUSION: RIMT can improve ventilatory function, respiratory endurance, and the perceived difficulty of breathing in patients with complete cervical spinal cord injury within half a year after trauma.  相似文献   
56.
Preparing healthcare students for community care has been emphasised due to the global ageing population. An instrument to measure students’ community care competency is lacking. This study aimed to develop and evaluate the psychometric properties of a new scale known as Community Care Competency Scale (CCCS) for measuring nursing students’ community care competency. CCCS consists of 21 items derived from literature review and community care standards. Content validity was established through a panel of seven experts in the areas of knowledge with a content validity index of 0.96. A cross‐sectional study was undertaken in a university in Singapore by using an anonymous self‐administered questionnaire to nursing students, and obtained a response rate of 87% (n = 283). Psychometric properties were explored using convergent and known‐group validity testing, exploratory factor analysis (EFA), confirmatory factor analysis (CFA) and Cronbach's alpha test. The results showed good convergent and known‐group validity. EFA and CFA showed a coherent construct of the 21 items of CCCS in a one‐factor model. The Cronbach's alpha of 0.94 indicated excellent internal consistency. The CCCS is a valid, reliable and easy‐to‐administer instrument that measures community care competency. This instrument will contribute to the empirical body of knowledge on evaluating the effectiveness of community care educational programmes for nursing students to prepare future healthcare professionals.  相似文献   
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Humans are able to learn tool-handling tasks, such as carving, demonstrating their competency to make movements in unstable environments with varied directions. When faced with a single direction of instability, humans learn to selectively co-contract their arm muscles tuning the mechanical stiffness of the limb end point to stabilize movements. This study examines, for the first time, subjects simultaneously adapting to two distinct directions of instability, a situation that may typically occur when using tools. Subjects learned to perform reaching movements in two directions, each of which had lateral instability requiring control of impedance. The subjects were able to adapt to these unstable interactions and switch between movements in the two directions; they did so by learning to selectively control the end-point stiffness counteracting the environmental instability without superfluous stiffness in other directions. This finding demonstrates that the central nervous system can simultaneously tune the mechanical impedance of the limbs to multiple movements by learning movement-specific solutions. Furthermore, it suggests that the impedance controller learns as a function of the state of the arm rather than a general strategy.  相似文献   
60.
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