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A prospective study was undertaken to determine if patients recover pre-injury level of shoulder function 1 year after 1 part proximal humeral fractures. Of the 67 patients enrolled, 43 were female and 24 male with an average age of 64.8 years (range, 25-90 years). All patients underwent a similar treatment protocol consisting of early therapy for range of shoulder motion and strengthening. Baseline demographics and functional assessment, including the American Shoulder and Elbow Surgeons (ASES) evaluation form and the SF-36, were obtained at the time of injury. Functional and demographic data were evaluated with a Student's t test. Fifty-four patients (80%) completed a 1-year follow-up. By 3 months, all patients attained radiographic and clinical evidence of union and no loss of reduction. At 1 year, the ASES score was similar to pre-injury status (93.7 vs 99.1; P = .12). The range of shoulder motion of the affected side was diminished compared to the unaffected extremity in internal rotation (P < .001) and external rotation (P < .001) but not forward flexion. Patients, who sustain minimally displaced proximal humeral fractures treated nonoperatively, largely returned to preoperative functional status at 1-year follow-up. Patients should be counseled and made aware of the decreased range of shoulder motion following this fracture.  相似文献   
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Nicotine withdrawal causes somatic and negative affective symptoms that contribute to relapse and continued tobacco smoking. So far, the neuronal substrates involved are not fully understood, and an opioid role has been suggested. In this regard, the opioid dynorphin (Dyn) is of interest as it produces aversive states and has been speculated to play a role in the nicotine behavioral syndrome. These studies explore whether Dyn metabolism is altered during withdrawal following chronic administration of nicotine. Mice were administered nicotine, 2 mg/kg, s.c., four times daily for 14 days, and Dyn and prodynorphin (PD) mRNA estimated in selective brain regions at various times (30 min to 96 h) following drug discontinuation. The content of Dyn, estimated by RIA, was decreased in the striatum for a protracted time, from 30 min to over 72 h. In contrast, the mRNA for PD, evaluated by Northern blot, was elevated, appearing by 8 h and lasting over 96 h. Dyn was decreased in both ventral and dorsal striatum, and PD mRNA was differentially increased in the two striatal compartments as demonstrated by in situ hybridization. PD message was predominantly augmented in the nucleus accumbens, rostral pole, core, and shell, and the medial aspects of caudate/putamen. We interpret these data to indicate increased activity of striatal, particularly accumbal, dynorphinergic neurons during nicotine withdrawal resulting in enhanced peptide release and compensatory synthesis. Heightened dynorphinergic tone might be responsible, in part, for the emergence of the negative affective states observed during nicotine withdrawal.  相似文献   
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We performed a prospective, randomised trial to evaluate the outcome after surgery of displaced, unstable fractures of the distal radius. A total of 280 consecutive patients were enrolled in a prospective database and 88 identified who met the inclusion criteria for surgery. They were randomised to receive either bridging external fixation with supplementary Kirschner-wire fixation or volar-locked plating with screws. Both groups were similar in terms of age, gender, hand dominance, fracture pattern, socio-economic status and medical co-morbidities. Although the patients treated by volar plating had a statistically significant early improvement in the range of movement of the wrist, this advantage diminished with time and in absolute terms the difference in range of movement was clinically unimportant. Radiologically, there were no clinically significant differences in the reductions, although more patients with AO/OTA (Orthopaedic Trauma Association) type C fractures were allocated to the external fixation group. The function at one year was similar in the two groups. No clear advantage could be demonstrated with either treatment but fewer re-operations were required in the external fixation group.  相似文献   
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Poly(ethylene glycol) (PEG)-modified thiolated gelatin (PEG-SHGel) anoparticles were developed as a long-circulating passively targeted delivery system that responds to intracellular glutathione concentrations to enhance DNA delivery and transfection. Reporter plasmid expressing enhanced green fluorescent protein (EGFP-N1) was encapsulated in the nanoparticles. DNA-containing gelatin (Gel) and thiolated gelatin (SHGel) nanoparticles were found to have a size range of 220 to 250 nm, whereas surface modification with PEG resulted in particles with a slightly larger size range of 310 to 350 nm. PEG modification was confirmed by electron spectroscopy for chemical analysis (ESCA), where an increase in the ether peak intensities of the C1s spectra corresponds to the surface presence of ethylene oxide residues. In addition, the PEG-SHGel nanoparticles released encapsulate plasmid DNA in response to varying concentrations of glutathione (up to 5.0 mM GSH in phosphate-buffered saline, or PBS). The stability of the encapsulated DNA was confirmed by agarose gel electrophoresis. Finally, from the qualitative and quantitative results of in vitro transfection studies in murine fibroblast cells (NIH3T3), PEG-Gel and PEG-SHGel nanoparticles afforded the highest transfection efficiency of the reporter plasmid. The results of these studies show that PEG-modified thiolated gelatin nanoparticles could serve as a very efficient nanoparticulate vector for systemic DNA delivery to solid tumors where the cells are known to have significantly higher intracellular GSH concentrations.  相似文献   
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