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71.
72.
Motor learning is the means by which we acquire skilled movements and consign them to permanent memory. Multiple brain areas are involved, and patients with neurological damage often experience difficulty when attempting to relearn previously learned skills. For these patients, the location of the lesion may be critical in influencing their motor skill relearning. The cerebellum has been described as an “on-line” comparator and corrector of movement, but recent research suggests that the cerebellum may also have a role in the later stages of motor learning, including the automation of movement patterns, although conflicting research in this area means that there is as yet no consensus. This knowledge may have implications for the way physiotherapists treat patients with cerebellar lesions. Some treatments in regular use by physiotherapists are discussed, and possible implications for practice are considered.  相似文献   
73.
Tendon injuries are common in either the workplace or sport activities, with some 3 to 5 million tendon and ligament injuries occurring annually worldwide. Management of tendon injury currently follows two routes: Conservative (rehabilitation and pain relief), or surgical. Irrespective of which of these primary treatment routes are followed, even if healing does occur, it may not result in a full gain of function. The inability of the tendon to self-repair and the relative inefficiency of current treatment regimens suggest that identifying alternative strategies is a priority. One such alternative is the use of stem cells to repair damage, either through direct application or in conjunction with scaffolding. We describe the current state of the art in terms of: (i) Molecular markers of tendon development, (ii) stem cell applicability to human tendon repair, (iii) scaffolding for in vitro tendon generation, and (iv) chemical/molecular approaches to both induce stem cell differentiation into tenocytes and maintain their proliferation in vitro.  相似文献   
74.
Complications of plate fixation in metacarpal fractures   总被引:6,自引:0,他引:6  
BACKGROUND: The objective of this study is to assess the complications after open reduction and plate fixation of extra-articular metacarpal fractures. METHODS: We retrospectively reviewed the clinical and radiologic records of 129 consecutive patients with 157 metacarpal fractures treated by open reduction and internal fixation with plates between 1993 and 1999. Intra-articular fractures and fractures of the thumb metacarpal were excluded. Eighty-one patients (64 men and 17 women) with 104 fractures were available for review, at an average follow-up of 13.6 months (range, 6-27 months). RESULTS: Twenty-eight patients (35%) and 33 fractures (32%) had one or more complications, including difficulty with fracture healing (12 patients [15%]), stiffness (eight patients [10%]), plate loosening or breakage (seven patients [8%]), complex regional pain syndrome (two patients), and one patient who developed a deep infection. CONCLUSION: Despite technical advances in implant material, design, and instrumentation, plate fixation of metacarpal fractures remains fraught with complications and unsatisfactory results.  相似文献   
75.
Cellular basis for progesterone neuroprotection in the injured spinal cord   总被引:19,自引:0,他引:19  
Progesterone (PROG) exerts beneficial and neuroprotective effects in the injured central and peripheral nervous system. In the present work, we examine PROG effects on three measures of neuronal function under negative regulation (choline acetyltransferase [ChAT] and Na,K-ATPase) or stimulated (growth-associated protein [GAP-43]) after acute spinal cord transection injury in rats. As expected, spinal cord injury reduced ChAT immunostaining intensity of ventral horn neurons. A 3-day course of intensive PROG treatment of transected rats restored ChAT immunoreactivity, as assessed by frequency histograms that recorded shifts from predominantly light neuronal staining to medium, dark or intense staining typical of control rats. Transection also reduced the expression of the mRNA for the alpha3 catalytic and beta1 regulatory subunits of neuronal Na,K-ATPase, whereas PROG treatment restored both subunit mRNA to normal levels. Additionally, the upregulation observed for GAP-43 mRNA in ventral horn neurons in spinal cord-transected rats, was further enhanced by PROG administration. In no case did PROG modify ChAT immunoreactivity, Na,K-ATPase subunit mRNA or GAP-43 mRNA in control, sham-operated rats. Further, the PROG-mediated effects on these three markers were observed in large, presumably Lamina IX motoneurons, as well as in smaller neurons measuring approximately <500 micro2. Overall, the stimulatory effects of PROG on ChAT appears to replenish acetylcholine, with its stimulatory effects on Na,K-ATPase seems capable of restoring membrane potential, ion transport and nutrient uptake. PROG effects on GAP-43 also appear to accelerate reparative responses to injury. As the cellular basis for PROG neuroprotection becomes better understood it may prove of therapeutic benefit to spinal cord injury patients.  相似文献   
76.
77.
Background: After open or laparoscopic Roux-en-Y gastric bypass (RYGBP) for morbid obesity, the bypassed stomach and duodenum are not readily available for radiological and endoscopic evaluation. Furthermore, little is known about the long-term physiologic and histologic changes that occur in the bypassed GI segments following these procedures. Many alternative radiological and endoscopic techniques have been described to access the distal gastric pouch and the duodenum after RYGBP. Apart from percutaneous gastrografin? studies, all these techniques require the insertion of a gastrostomy tube in the distal stomach. Methods: a new diagnostic method to access the bypassed segments by virtual CT gastroscopy (VG) was used in 5 morbidly obese patients who underwent laparoscopic RYGBP (LRYGBP). Results: All patients tolerated the procedure well, which appears safe and suitable for an outpatient setting.The virtual images offered an excellent intraluminal view of the stomach and duodenum. Conclusions: VG holds promise as the method of choice in the follow-up of LRYGB patients, having the potential to detect inflammatory changes and cancer in the excluded segments early.  相似文献   
78.
This study analyzes the efficacy of occlusal devices for the long-term stability of contouring of the lower face by injection of Botulinum toxin type A in a prospective clinical protocol. Ten patients (seven female and three male) with a widened lower face were recruited consecutively between January 2006 and January 2007. Each patient was advised to wear an occlusal device to release masticatory muscles, and percutaneous intramuscular injections of Botulinum toxin type A were used. The follow-up study was 18 months. Facial changes were noted by the patients as early as 2 weeks after the injection and lasted for 18 months; all patients reported an improved facial profile. There were no complications. Botulinum toxin type A injection for the contouring of the lower face is a simple technique, has few side effects, and allows a rapid return to daily life. In our study, the long-term stability of the result is related to the occlusal therapy performed after the injection of botulinum toxin type A.  相似文献   
79.
OBJECTIVE: This prospective study quantified cytokine and chemokine levels in seminal plasma of patients with chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) and benign prostatic hyperplasia (BPH), to evaluate inflammatory mediators as possible surrogate markers for diagnosis and treatment efficacy. METHODS: Seminal plasma levels of eight cytokines and nine chemokines were evaluated by multiplex arrays in 83 men: 20 healthy controls and 9 men with CP/CPPS IIIA, 31 with CP/CPPS IIIB, and 23 with BPH. Prostate samples obtained by transurethral resection of the prostate from 13 patients with BPH were analysed by immunohistochemistry to detect interleukin 8 (IL-8)-producing cells and characterise inflammatory infiltrates. RESULTS: Significantly increased levels of cytokines (IL-1alpha, IL-1beta, IL-6, IL-10, IL12p70) and chemokines (CCL1, CCL3, CCL4, CCL17, CCL22, CXCL8/IL-8) were observed in seminal plasmas from patients with CP/CPPS or BPH. However, only IL-8 was significantly elevated compared to controls (median [quartiles] 1984 [1164-2444] pg/ml), in patients with CP/CPPS IIIA (15,240 [10,630-19,501] pg/ml; p<0.0001), CP/CPPS IIIB (2983 [2033-5287] pg/ml; p=0.008), and BPH (5044 [3063-11,795] pg/ml, p<0.0001), discriminating CP/CPPS IIIA versus IIIB (accuracy=0.882+/-0.078; p=0.001). Inflammatory infiltrates were detected in prostate samples from 13 of 13 BPH patients, and IL-8-producing prostate cells in 11 of 13 samples. IL-8 concentration in seminal plasma was positively correlated with symptom score and prostate-specific antigen levels both in CP/CPPS and BPH patients. CONCLUSIONS: IL-8 is expressed in situ by epithelial and stromal prostate cells and is functional, as shown by recruitment of cells expressing cognate receptors in BPH prostate tissue, indicating its involvement in disease pathogenesis. Among all the cytokines and chemokines analysed, IL-8 appears to be the most reliable and predictive surrogate marker to diagnose prostate inflammatory conditions, such as CP/CPPS and BPH.  相似文献   
80.
Diagnosis of neurofibromatosis 1 is based on clinical criteria. In a large number of children with neurofibromatosis 1, magnetic resonance imaging (MRI) reveals high-signal T(2)-weighted intensities in different brain regions, defined as unidentified bright objects. These lesions are asymptomatic; most of them regress spontaneously with age, but the presence of contrast enhancement or mass effect in them usually strongly suggests an increased risk of proliferative changes. To date, few studies have focused on evoked potentials in patients with neurofibromatosis 1, and the reported abnormalities did not have significant clinical correlations. We describe the clinical and instrumental (MRI and evoked potentials) follow-up of three patients with neurofibromatosis 1. MRI and evoked potentials showed subclinical involvement of the central nervous system. Some MRI T(2)-weighted hyperintensities showed enhancement and mass effect of uncertain significance. During follow-up, the MRI lesions spontaneously decreased in size or enhancement, allowing us to exclude the hypothesis of proliferative lesions; in the same way, some asymptomatic evoked potential abnormalities disappeared. These findings suggest that both MRI and evoked potentials could be useful in the detection and monitoring of cerebral complications of neurofibromatosis 1.  相似文献   
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