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81.

Background

The purpose of the present study is to evaluate a single surgeon’s short, intermediate, and long-term clinical, functional, and radiographic outcomes with a trapeziectomy with flexor carpi radialis (FCR) suspension arthroplasty without tendon interposition (LRSA).

Methods

Twenty-one patients underwent 26 FCR suspension arthroplasties without tendon interposition by a single senior surgeon. All patients had Eaton stage III and IV carpometacarpal (CMC) osteoarthritis. The Patient-Rated Wrist and Hand Evaluation (PRWHE) and Quick Disabilities of Arm, Shoulder, and Hand (QuickDASH) were used to evaluate functional outcomes. A comprehensive strength and range of motion evaluation was performed to evaluate clinical outcomes. Plain radiographs at rest and with maximal pinch were performed to evaluate for arthroplasty space subsidence.

Results

The LRSA exhibited consistent clinical and functional outcomes throughout postoperative follow-up. As the average patient age and time from surgery increased, range of motion (ROM) and PRWHE scores stayed relatively constant, while lateral tip and tip pinch strength deteriorated with time. The LRSA prevented the proximal migration of the first metacarpal in all but one patient. No patients required revision arthroplasty following LRSA.

Conclusions

This study demonstrates the consistent short, intermediate, and long-term clinical, functional, and radiographic outcomes following a trapeziectomy with FCR suspension arthroplasty.
  相似文献   
82.
It is essential to minimize the unnecessary discard of procured deceased donor kidneys, but information on discard rates and the extent to which discard can be avoided are limited. Analysis of the UK Transplant Registry revealed that the discard rate of procured deceased donor kidneys has increased from 5% in 2002‐3 to 12% in 2011‐12. A national offering system for hard‐to‐place kidneys was introduced in the UK in 2006 (the Declined Kidney Scheme), but just 13% of kidneys that were subsequently discarded until 2012 were offered through the scheme. In order to examine the appropriateness of discard, 20 consecutive discarded kidneys from 13 deceased donors were assessed to determine if surgeons agreed with the decision that they were not implantable. Donors had a median (range) age of 67 (31–80) yr. Kidneys had been offered to a median of 3 (1–12) centers before discard. Four (20%) of the discarded kidneys were thought to be usable, and nine (45%) were possibly usable. As a result of these findings, major changes to the UK deceased donor kidney offering system have been implemented, including simultaneous offering and broader entry criteria for hard‐to‐place kidneys. Organizational changes are necessary to improve utilization of deceased donor kidneys.  相似文献   
83.
BACKGROUND: Porcine livers perfused with human blood destroy 85% of human erythrocytes (red blood cells [RBC]) during prolonged extracorporeal perfusion, raising the possibility of a complement-mediated graft-versus-host effect. METHODS: Isolated porcine livers were perfused with fresh human blood. Plasma samples were analyzed for complement production by reverse CH50 analysis and porcine immunoglobulin class and specificity by enzyme-linked immunosorbent assay (ELISA) and flow cytometry. Anti-CD59 and anti-decay accelerating factor (DAF) monoclonal antibody were used to investigate whether human complement regulatory proteins inhibit porcine complement. RESULTS: After 64 hr of perfusion of porcine livers with human blood, mean complement activity in the perfusate was 95% of the starting value and increasing, whereas perfusion in the absence of a liver showed a falling complement activity of 28.7%. ELISA demonstrated porcine immunoglobulin (Ig) G and IgM in the xenoperfused human plasma. Whereas in a previous study flow cytometry demonstrated porcine antibodies specific for antigens on human T lymphocytes, in this study, anti-human RBC antibodies were not found. Xenoperfused human plasma did not lyse fresh human RBC. Human complement was consistently more efficient at lysing porcine RBC than was porcine complement at lysing human RBC, and human plasma inhibited the ability of porcine plasma to lyse human RBC, raising the possibility of cross-species complement regulation. Complement regulatory proteins on human RBC were blocked using mouse monoclonal anti-human CD59 and DAF. Blocking CD59, but not DAF, augmented lysis of human RBC by porcine complement. CONCLUSIONS: Human CD59 inhibits porcine complement. The production of porcine complement from xenoperfused porcine livers is unlikely to result in clinically significant injury mediated through the classical pathway of complement activation.  相似文献   
84.
Differential expression of hZnT-4 in human prostate tissues   总被引:2,自引:0,他引:2  
BACKGROUND: Altered zinc levels in prostate benign prostatic hyperplasia (BPH) and carcinoma is well documented. It is not known whether loss of zinc, necessary to restrain aggressive growth, results from loss of a single specific or multiple zinc transporters. METHODS: Human prostate tissues from patients who underwent radical prostatectomy were screened by RT-PCR analysis for five zinc transporters. Relative cDNA expression was determined in normal, BPH, and tumor specimens and four prostate epithelial cell lines. RESULTS: Surgical specimens were obtained from patients with assigned Gleason scores ranging from 5 to 9. Relative expression of hZIP-1 and hZnT-1 were prominent in most samples with relatively lesser degree of expression of hZIP-2 and no detectable expression of hZnT-3. Expression of hZnT-4 was decreased in BPH and tumor samples compared to normal tissue. CONCLUSIONS: These data suggest that zinc homeostasis in normal prostate tissues results from an interplay of multiple transporters and decreased hZnT-4 expression is associated with prostate tissue abnormalities independent of total cellular zinc content.  相似文献   
85.
R J Quinn  S P Butler 《Journal of nuclear medicine》1991,32(11):2050-5; discussion 2056
There remains no clear consensus as to the appropriate further investigation and management of the patient suspected of pulmonary embolism (PE) who has an intermediate lung scan. Clinical assessment is documented as unreliable, yet many of these patients are unlikely to be treated or to have further tests despite a 36% chance of having PE. Using Medical Decision Analysis, four management strategies for such patients have been examined in terms of mortality and morbidity up to 6 mo post-presentation. The strategies were: (1) treat all patients; (2) treat no patients; (3) perform pulmonary angiography; and (4) perform contrast venography. In the last two strategies, the patients with positive examinations are treated; those with negative examinations are not treated. An extensive literature review was performed to provide probability estimates of chance events and outcomes. If all patients are treated, there is 96.8% chance of survival, with an 85.8% chance of survival with no major complications. If no patients are treated, survival is 89.3% and complication-free survival is 89.3%. Angiography and venography results were 96.7%, 93.1% and 94.6% and 89.6%, respectively. We conclude that in patients suspected of PE who have intermediate lung scan results, the optimal strategy is pulmonary angiography since this results in the highest survival with the lowest complications.  相似文献   
86.
87.
To determine whether arachidonic acid stimulates the secretion of ovine placental lactogen (oPL), arachidonic acid was infused as an intravenous bolus into pregnant ewes and fetuses. Plasma oPL concentrations were determined in mothers and fetuses before and for 5 h after infusion. The administration of 12.5 mg arachidonic acid (0.15-0.2 mg/kg, n = 11 experiments) to the pregnant ewes caused an increase in maternal plasma oPL concentrations of 73.9 +/- 15.6% (S.E.M.) and 60.8 +/- 18.1% above the pretreatment concentrations at 4 and 5 h respectively (P less than 0.01 in each instance). The infusion of 25 mg arachidonic acid (n = 8) caused increases of 96.0 +/- 19.1% and 100.3 +/- 26.4% (P less than 0.005), and the stimulation was not inhibited by the cyclo-oxygenase inhibitors indomethacin and ibuprofen. In contrast to arachidonic acid, vehicle alone or palmitic acid had no effects on plasma oPL concentrations. Despite the increase in maternal plasma oPL concentrations, plasma oPL concentrations in the fetus remained unchanged after the maternal infusions. The infusion of arachidonic acid (0.5-1.5 mg/kg) directly into six fetuses had no effects on either fetal or maternal oPL concentrations. These studies indicate that arachidonic acid stimulates maternal plasma oPL concentrations but has no effect on fetal oPL concentrations and the stimulation of oPL secretion is not due to the conversion of arachidonic acid to prostaglandins or other cyclo-oxygenase products.  相似文献   
88.
Prolongation of QT interval and antiarrhythmic action of bepridil   总被引:1,自引:0,他引:1  
Studies were undertaken with bepridil, a new calcium blocker that prolongs the QT interval, to determine the antiarrhythmic and possible arrhythmogenic properties of this agent. The technique of programmed electrical stimulation was employed to evaluate bepridil in 15 patients with symptomatic ventricular tachycardia (VT). Bepridil prevented VT induction in 7 of 15 patients. Bepridil prolonged the QT and refractoriness and a linear correlation could be demonstrated between the percent change in QTc and refractory period prolongation for the bepridil-protected group. Bepridil in one patient reduced by one the number of stimuli required to induce VT, but no spontaneous arrhythmias were noted. Bepridil thus possesses antiarrhythmic properties with a minimal proarrhythmic effect.  相似文献   
89.
An overall decline in the availability of osteogenic precursor cells and growth factors in the bone marrow microenvironment have been associated with impaired bone formation and osteopenia in humans. The objective of the current study was to determine if transplantation of mesenchymal stromal cells (MSC) from a healthy, young donor mouse into an osteopenic recipient mouse could enhance osseointegration of a femoral implant. MSC harvested from normal young adult mice differentiated into bone forming osteoblasts when cultured on implant grade titanium surfaces ex vivo and promoted bone formation around titanium-coated rods implanted in the femoral canal of osteopenic recipient mice. Micro computed tomographic imaging and histological analyses showed more, better quality, bone in the femur that received the MSC transplant compared with the contra-lateral control femur that received carrier alone. These results provide pre-clinical evidence that MSC transplantation promotes peri-implant bone regeneration and suggest the approach could be used in a clinical setting to enhance bone regeneration and healing in patients with poor quality bone.  相似文献   
90.

OBJECTIVE

To determine whether hormonal manipulation improves the biochemical outcome for men with intermediate or high‐risk prostate cancer and undergoing permanent brachytherapy with or without supplemental external beam radiation therapy.

PATIENTS AND METHODS

From April 1995 to August 2000, 350 patients with intermediate‐risk (225 men; a Gleason score of ≥ 7 or a prostate specific antigen, PSA, level of ≥ 10 ng/mL or clinical stage ≥ T2b) or high‐risk features (125 men; two or three of a Gleason score of ≥ 7 or PSA ≥ 10 ng/mL or clinical stage ≥ T2b) underwent transperineal ultrasonography‐guided permanent brachytherapy. No patient underwent pathological lymph node staging. Of these patients, 293 received supplemental external beam radiation therapy (EBRT), 141 received hormonal manipulation, with 82 having hormonal therapy for ≤ 4 months (median 4) for cytoreduction, while 59 had neoadjuvant and adjuvant hormonal manipulation (median 8 and 12 months for intermediate‐ and high‐risk, respectively). The median patient age was 68.5 years. No patient was lost to follow‐up. The mean (sd ) and median follow‐up was 50 (18) and 49 months (calculated from the day of implantation). Biochemical disease‐free (BDF) survival was defined using a consensus definition. The clinical variables evaluated for BDF survival included risk group, Gleason score, patient age, clinical T‐stage and pretreatment PSA. Treatment variables included use of hormonal manipulation stratified into cytoreductive (≤ 4 months) vs adjuvant (> 4 months) regimens, supplemental EBRT, isotope and dosimetric variables.

RESULTS

For intermediate‐risk patients, the 6‐year actuarial BDF survival rates were 98%, 96% and 100% for hormone naïve, cytoreductive and adjuvant treatment, respectively (P = 0.693); for high‐risk patients the respective values were 79%, 94% and 92% (P = 0.046). When stratified by pretreatment PSA, hormonal manipulation improved the outcome for patients with a PSA of ≥ 10 ng/mL (P = 0.019), but not for those with < 10 ng/mL (P = 0.661). Hormonal status was not statistically significant in predicting biochemical outcome when stratified by Gleason score. The follow‐up in hormone‐naïve patients was significantly longer than that in hormonally manipulated patients, at 55 (20) vs 43 (15) months (P < 0.001). In a multivariate analysis only the Gleason score predicted failure in intermediate‐risk patients, while pretreatment PSA, the use of hormonal manipulation and Gleason score predicted the outcome in high‐risk patients (P = 0.035). For both hormone‐naïve and hormonally manipulated BDF patients, the median PSA level after implantation was < 0.1 ng/mL.

CONCLUSION

In patients treated by permanent prostate brachytherapy, hormonal manipulation improved the biochemical outcome for those at high‐risk and those with an initial PSA of ≥ 10 ng/mL, but not for those with intermediate‐risk features. The use of hormonal therapy for> 4 months conferred no additional biochemical advantage over short‐course regimens. Because the follow‐up in hormone‐naïve patients was longer than that for those receiving hormonal manipulation, additional follow‐up will be mandatory to confirm the durability of these findings.
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