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991.
992.

Background  

Lag screw cut-out failure following fixation of unstable intertrochanteric fractures in osteoporotic bone remains an unsolved challenge. This study tested if resistance to cut-out failure can be improved by using a dual lag screw implant in place of a single lag screw implant. Migration behavior and cut-out resistance of a single and a dual lag screw implant were comparatively evaluated in surrogate specimens using an established laboratory model of hip screw cut-out failure.  相似文献   
993.
Defects involving the distal leg and foot are frequently encountered following various aetiological factors. Paucity of local tissue causes surgeons to resort to the retrograde peninsular flap, the cross leg flap or the free flap. With specific knowledge of perforators, the fasciocutaneous flap from the calf area can be transferred to the defect in a single stage based on skeletonised distal perforators. The surgical anatomy, flap planning and procedure have been detailed. Nineteen patients were treated during the period 1995 to 2005. The perforators were identified preoperatively by audio Doppler. The flaps were marked and dissected proximal to the defect skeletonising the distal perforators under loupe magnification and transferred to the defect in a single stage. The donor site was skin grafted. Out of 19 cases, 16 flaps healed uneventfully, one flap necrosed completely and in two cases there was marginal necrosis. The cases were followed up for 2-10 years with an average of 6 years. With detailed knowledge of perforators one can safely reconstruct distal moderate-size defects of the lower limb in a single stage, thus having the benefits of free tissue transfer without resorting to microsurgery. This technique has proved to be an advancement in the reconstructive repertoire allowing flaps of non conventional dimensions to be perfused by skeletonised perforators.  相似文献   
994.
Transplant patients are at the risk for posttransplant lymphoproliferative disease (PTLD), a virally-driven malignancy. Induction with the depleting antibody preparations Thymoglobulin and OKT3 is associated with PTLD suggesting that the T-cell depletion increases PTLD risk. We therefore studied 59 560 kidney recipients from the Organ Procurement and Transplantation Network/United Network for Organ Sharing (OPTN/UNOS) database for a relationship between induction agent use and PTLD. Two agents with comparable T-cell depletional effects, alemtuzumab and Thymoglobulin, were compared to nondepletional induction agents or no induction. The overall incidence of PTLD was 0.46% and differed significantly by induction strategy (p < 0.01): without induction (0.43%), basiliximab (0.38%), daclizumab (0.33%), Thymoglobulin (0.67%) and alemtuzumab (0.37%). Thymoglobulin was associated with significantly increased PTLD risk (p = 0.0025), but alemtuzumab (p = 0.74), basiliximab (p = 0.33) and daclizumab, which trended toward a protective effect (p = 0.06), were not. Alemtuzumab and Thymoglobulin treated patients did not differ in any established parameter affecting PTLD risk although alemtuzumab is known to have a more pronounced B-cell depleting effect. Interestingly, maintenance therapy with an mTOR inhibitor was strongly associated with PTLD (0.71%, p < 0.0001). Thus, depletional induction is not an independent risk factor for PTLD. Rather, maintenance drug selection or perhaps the balance between B- and T-cell depletion may be more relevant determinants of PTLD risk.  相似文献   
995.
Diverticula arising from the mitral valve are very rare. They are usually detected by echocardiography as masses arising from the cardiac valves. We present a case of an incidental finding of a diverticulum arising from the mitral valve. This was initially detected by transesophageal echocardiography, and later confirmed by pathologic appearance. The case illustrates the unique findings on echocardiography that would help to differentiate diverticula from other valvular masses.  相似文献   
996.
The changes in spike activity of single neurons of the compact part of the substantia nigra, evoked by nucleus caudatus stimulation under conditions of long-term registration of the single and multiple, isolated and combined actions of GABA, GABA-amide, glutamine, and ethanolamine-O-sulfate (EOS) were studied in albino rats. Inhibition of poststimulus activity under GABA action was recorded and the inhibitory effect of GABA-amide was revealed. Primary excitatory and subsequent inhibitory effects of glutamine in combination with EOS were shown. The subsequent administration of bacterial melanin, synthesized by a mutant culture of Bacillus thuringiensis (BT-M) evoked a clear-cut and prolonged excitatory reaction during all the combined actions of GABA, GABA-amide, glutamine, and EOS. Preliminary administration of BT-M abolished the inhibitory poststimulus effects of GABA, GABA-amide, and EOS, as well as glutamine-induced excitation.  相似文献   
997.
BACKGROUND: Imatinib mesylate (IM), the first-line treatment of chronic myeloid leukaemia (CML), is a tyrosine kinase inhibitor that targets those proteins involved in BCR-ABL signal transduction in CML, c-kit (KIT) and platelet-derived growth-factor (PDGFR) receptor. The use of IM has been associated with cutaneous reactions. In the last 2 years numerous studies have focused the attention on hypopigmentations, depigmentations and photosensitivity developing after the initiation of IM therapy. OBJECTIVE: The aim of this study is to evaluate the effects of IM therapy on the skin pigmentation of five patients affected by CML. METHODS: Skin pigmentation measurements were performed with a Minolta CR-200 Chromameter. results: All the studied patients show the gradual lightening of the skin on unexposed areas over the treatment with IM. In particular, this explorative colorimetric study indicates the association between IM and skin depigmentation with a significant increase of luminance value (L*) (P = 0.001) and a significant decrease of the pigmentation value (b*) (P = 0.028). CONCLUSION: Even if we do not know the clinical significance of the skin depigmentation caused by IM, the regulatory role of KIT and its ligand stem cell factor in melanocyte development and survival seems to suggest an objective mechanism of action for IM in the pathogenesis of this cutaneous depigmentation.  相似文献   
998.
BACKGROUND: At long-term follow up we cannot easily differentiate between patients who have undergone free transverse rectus abdominis musculocutaneous (TRAM) flap and deep inferior epigastric artery perforator (DIEP) flap breast reconstruction in terms of subjective functional limitations of daily activities. The aim of this study was to evaluate postoperative outcomes and long-term subjective functional deficit in patients following unilateral free TRAM compared with DIEP flap breast reconstruction. METHODS: Sixty consecutive patients who underwent unilateral autologous breast reconstruction were included in the study, 30 of whom had undergone a DIEP flap, and 30 a free TRAM flap. Surgical and postoperative outcome data were collected and a postal questionnaire was sent to each patient at least 6 months postoperatively consisting of a short functional assessment questionnaire and a Short Form 36 (SF-36) survey. RESULTS: We found no significant difference in postoperative outcomes or in the subjective ability to perform activities of daily living, including work, domestic activities, sports and hobbies, between patients who underwent TRAM flap breast reconstruction and those who underwent a DIEP flap, and no significant difference between the groups for scores on the physical functioning, role-physical, or bodily pain scales of the SF-36. CONCLUSION: We conclude that harvesting of the free TRAM flap results in no significant difference in postoperative outcomes or in the subjective ability to perform activities of daily living compared with the DIEP flap.  相似文献   
999.
A dry powder aerosol formed of human growth hormone (hGH), lactose and dipalmitoylphosphatidylcholine was assessed for systemic delivery of the hormone in rats. The fate of the protein locally in the deep lung was examined post-delivery. The powder was prepared by spray-drying and presented a primary particle diameter of 4.4 microm and a tap density of 0.069 g/cm(3). The mass median aerodynamic diameter was 4.4 micron in the multi-stage liquid impinger at 60 l/min using a Spinhaler device. The emitted dose and fine particle fraction were 89% and 58%, respectively. Varying the airflow rate from 30 to 90 l/min had limited impact on aerosolization properties in vitro. No hGH dimers or glycation adducts were produced during formulation of the powder. hGH absorbed into the bloodstream with a time to peak of 23 and 52 min and with an absolute bioavailability of 23% and 8% following intratracheal insufflation of the dry powder and intratracheal spray-instillation of a solution of the hormone, respectively. Confocal imaging of rat lung revealed an intense uptake of fluorescein isothiocyanate (FITC)-hGH by alveolar macrophages as early as 1 h post-delivery. A dry powder aerosol made of selected GRAS excipients improved absorption of hGH from the lung over a simple solution.  相似文献   
1000.
AIMS: To investigate the association between estimated glomerular filtration rate (eGFR) and total and cardiovascular mortality in a population-based cohort of diabetic subjects. METHODS: A longitudinal study using a population-based district diabetes register comprising 3288 subjects in South Tees, UK. The eGFR was calculated using the Modification of Diet in Renal Disease (MDRD) study equation. Patients were stratified by baseline eGFR into five stages as per the National Kidney Foundation guidelines: Stage 1, eGFR > 90; Stage 2, eGFR 60-89; Stage 3, eGFR 30-59; Stage 4, eGFR 15-29; and Stage 5, eGFR < 15 ml/min per 1.73 m(2). Main outcome was all-cause and cardiovascular mortality between 1 January 1994 and 31 July 2004. RESULTS: At baseline, mean age (58.4 years) differed between groups. Persons with lower eGFR were older (P < 0.001). Thirty-six percent (n = 1193, males 56%) had died by 10 years (cardiovascular cause in 60%). Median follow-up was 10.5 years amounting to 28 342 person years. Stages 4 and 5 (eGFR 相似文献   
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