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European Journal of Orthopaedic Surgery & Traumatology - The management of limb-length discrepancy secondary to traumatic femoral bone loss poses a unique challenge for surgeons. The Ilizarov...  相似文献   
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The role of extracellular purine nucleotides, including adenosine triphosphate (ATP) and adenosine, as modulators of posttransplantation outcome and ischemia‐reperfusion injury is becoming increasingly evident. Upon pathological release of ATP, binding and activation of P2 purinergic surface receptors promote tissue injury and inflammation, while the expression and activation of P1 receptors for adenosine have been shown to attenuate inflammation and limit ischemia‐induced damage, which are central to the viability and long‐term success of allografts. Here we review the current state of the transplant field with respect to the role of extracellular nucleotide signaling, with a focus on the sources and functions of extracellular ATP. The connection between ischemia reperfusion, purinergic signaling, and graft preservation, as well as the role of ATP and adenosine as driving factors in the promotion and suppression of posttransplant inflammation and allograft rejection, are discussed. We also examine novel therapeutic approaches that take advantage of the ischemia‐reperfusion‐responsive and immunomodulatory roles for purinergic signaling with the goal of enhancing graft viability, attenuating posttransplant inflammation, and minimizing complications including rejection, graft failure, and associated comorbidities.  相似文献   
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Prostate and breast cancers are hormone-related malignancies and are characterized by a complex interplay of hundreds of susceptibility loci throughout the genome. Prostate cancer could be inhibited by eliminating androgens through castration or estrogen administration, thus facilitating long-term treatment of prostate cancer; however, the role of estrogen in prostate cancer remains unclear. This study aimed to determine whether polygenic risk scores (PRSs) comprising combinations of genome-wide susceptibility variants influence the clinical outcomes of prostate cancer patients. The study subjects were recruited from four medical centers in Taiwan, and genome-wide genotyping data were obtained from 643 prostate cancer patients. We derived the PRS for prostate cancer (PRS-PC) and for breast cancer (PRS-BC) for each patient. The association between the PRS-PC/PRS-BC at the age of prostate cancer onset and recurrence within seven years was evaluated using a regression model adjusted for population stratification components. A higher PRS-PC was associated with an earlier onset age for prostate cancer (beta in per SD increase in PRS = -0.89, P = 0.0008). In contrast, a higher PRS-BC was associated with an older onset age for prostate cancer (beta = 0.59, P = 0.02). PRS-PC was not associated with the risk of recurrence (hazard ratio = 1.03, P = 0.67), whereas a higher PRS-BC was associated with a low recurrence risk (hazard ratio = 0.86, P = 0.03). These results indicate that the genetic predisposition to breast cancer is associated with a low risk of prostate cancer recurrence. Further studies are warranted to explore the role of breast cancer susceptibility variants and estrogen signaling in prostate cancer progression.  相似文献   
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Background

Conventional imaging modalities are limited in the assessment of complex lower urinary tract anomalies including ectopic insertion of ureters. MR urography can be useful in these situations.

Objective

To share our experience with MR urography in assessing lower urinary tract anomalies and to determine its accuracy in depicting ectopic ureters.

Materials and methods

We conducted a retrospective review of all MR urography examinations done between November 2007 and March 2013 to note the presence or absence of duplex kidneys and insertion of ureters. We reviewed patient charts, surgical findings and results of other investigations including cystoscopy with retrograde ureterogram in order to establish presence or absence of ectopic ureter. This served as a reference standard against which we compared MR urography results.

Results

Of 22 MR urography examinations (3 boys, 19 girls; age range 3–16 years, mean 9.2 years) performed during the study period, 19 were performed to rule out ectopic ureters, two to assess complex anatomy and one to rule out crossing vessel in ureteropelvic junction obstruction. MR urography showed ectopic ureter in 9/19 children; one proved to be a false-positive. MR urography correctly showed normal insertion in 7/19 children. In the remaining 3/19 children distal ureter could not be seen, hence insertion was indeterminate on MR urography. One of these children had an ectopic ureter on cystoscopy and surgery. Statistical analysis showed MR urography’s sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) to be 88.8–100%, 70–90%, 75–88.8% and 90–100% for the detection of ectopic ureter.

Conclusion

MR urography is highly accurate in the assessment of ectopic ureters. In incontinent girls, MR urography should be the method of choice for depicting or ruling out ectopic ureter.  相似文献   
69.
Evolution of Visceral Sensitivity in Patients with Irritable Bowel Syndrome   总被引:17,自引:0,他引:17  
Irritable bowel syndrome (IBS) has been associated with visceral hypersensitivity. Here we examined the evolution of rectal sensitivity and of gastrointestinal symptomatology in IBS patients over time, to verify if the clinical and biological parameters showed parallel behavior. Patients complaining of IBS, identified by Rome 1 criteria, were included in this study. The severity of the gastrointestinal (Gastrointestinal) symptoms was assessed by a gastrointestinal index. The pain threshold to rectal distension was measured by a barostat programmed for phasic ascending distensions. Both measures were obtained before and after treatment. Thirty-nine patients were followed while on a 10-week group psychotherapy (psy) program. Twelve patients were controlled after pharmacological treatment with amitriptyline (Ami) 10 mg hours for two weeks and then 25 mg hours for the following 4 weeks. Clinical improvement with symptom reduction was achieved in both patients groups. With psy, the Gastrointestinal index declined from an initial value of 78.4 ± 4.8 to 65.5 ± 4.5 at the end of treatment (P < 0.05). With Ami, the gastrointestinal index decreased from 91.6 ± 5.6 to 61.8 ± 9.1 (p < 0.01). The pain threshold to rectal distension increased from 27.7 ± 1.0 to 33.7 ± 1.9 mmHg (P < 0.01) after drug treatment, but remained unchanged (30.6 ± 1.0 vs 30.6 ± 1.1 mm Hg) with psy. Evolution of the gastrointestinal index and rectal sensitivity were directly correlated (r = –0.71; P < 0.01) in Ami patients, but not in those treated with Psy (r = –0.001). In conclusion, visceral hypersensitivity appeared as a stable biological defect over a 10- to 12-week period during clinically-effective treatment with psychotherapy. Rectal pain threshold, however, seemed to be pharmacologically manipulatable in patients treated with Ami.  相似文献   
70.
Congenital Polycythemia in Chuvashia   总被引:2,自引:4,他引:2  
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