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841.
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843.
Radiotherapy for tumors can cause soft tissue necrosis, osteonecrosis, and pathologic fractures. A 47-year-old woman presented with a pathologic fracture of the left clavicle 10 years after radiotherapy following radical mastectomy for breast cancer. She was treated with a compound rib-latissimus dorsi osteomusculocutaneous flap with a 4-cm segment of the sixth rib. Fusion of the bones was achieved in three months. Donor site morbidity was cosmetically acceptable and function of the shoulder was improved. The Constant shoulder score which was 36 preoperatively increased to 88 after 38 months of follow-up.  相似文献   
844.
BACKGROUND: In the present study, we aimed to determine whether during coronary artery bypass grafting (CABG) surgery, dexmedetomidine has protective effects against cerebral ischemic injury. METHOD: Twenty-four patients, aged 50-70 years, undergoing CABG surgery were randomized into two groups of 12 patients each: those receiving dexmedetomidine (group D) and those not receiving it (group C). As basal blood samples from arterial and jugular bulb catheters were drawn, dexmedetomidine (1 microg/kg bolus and infusion at a rate of 0.7 microg/kg/h) was administered to patients in group D. Arterial and jugular venous blood gas analyses, serum S-100B protein (S-100B), neuron-specific enolase (NSE) and lactate measurements were performed after induction, 10 min after the initiation of cardiopulmonary bypass (CPB), 1 min after declamping, at the end of CPB, at the end of the operation and 24 h after surgery. Mann-Whitney U- and Wilcoxon's tests were used for statistical analyses. RESULTS: No significant between-group differences were found regarding arterial and jugular venous pH, PO(2), PCO(2) and O(2) saturations. S-100B, NSE and lactate levels were also similar between groups D and C. During the post-operative period, there were no clinically overt neurological complications in any patient. CONCLUSION: Cerebral ischemia marker (S-100B, NSE, lactate) patterns were as expected during CPB; however, there were no differences between the groups, which led us to believe that during CABG surgery dexmedetomidine has no neuroprotective effects. Future studies with larger populations are recommended to further establish the effects of this drug.  相似文献   
845.
It has been demonstrated that long-term administration of doxazosin, an alpha 1 adrenoceptor antagonist, causes an up-regulation in the expression of alpha 1 adrenoceptor subtype mRNAs in the rat genitourinary tract. The aim of this study is to determine whether this up-regulation does have any effect on contractile response of rabbit bladder neck to adrenaline, acethylcholine and papaverin after long-term doxazosin treatment. Fourteen rabbits, treated with doxazosin 3 mg/kg/day p.o for 6 months, and were fed with a diet of standard laboratory rabbit chow (100 g/kg/day). Ten rabbits received the same amount of regular chow but no drug. Contractile responses of rabbit bladder neck to adrenaline acethylcholine and papaverine were measured.  相似文献   
846.
Aim The aim of this study was to identify the genetic effects of Y chromosome and azoospermia factor (AZF) gene variation in men with infertility and to elucidate the molecular mechanism responsible for the identified point mutation. Methods Chromosome analysis was performed according to standard methods on lymphocyte cultured cells and genomic DNA was extracted from the peripheral blood. Three sets of primers were used encompassing the AZFb, AZFc and SRY14 gene regions. Products were genotyped with single-strand comformational polymorphisim (SSCP) analysis. Results The profiles of the mutated genes were detected in five of three azoospermic and two oligoasthenozoospermic infertile males. The SSCP variability of the AZFc gene was detected in all of the cases, while sex-determining region Y (SRY) gene variation was detected in two of the current cases. Three cases with oligoasthenozoospermia showed mutated SSCP profiles in both their SRY and AZFc gene regions. No AZFb variation was detected in the presented cases. Conclusion The AZF locus is assumed to contain the genes responsible for spermatogenesis in human. Deletions in these genes are thought to be involved in male infertility associated with azoospermia, oligozoospermia and/or both. AZF microdeletions and variations that are seen in infertile males suggest the need for molecular screening of such cases. Advance studies are also needed to detect of these variations and their relevance to male infertility before using assisted reproduction techniques in such cases.  相似文献   
847.
848.
Abstract   Objective: We aimed to investigate the risk factors for hospital mortality, short (five years) and mid-term (10 years) survival in patients who underwent mitral valve replacements in redo patients with previous mitral valve procedures. Patients and Methods: Between September 1989 and December 2003, 62 redo patients have undergone mitral valve replacements due to subsequent mitral valve problems. Preoperative, operative, and postoperative data were analyzed retrospectively and evaluated for risk factors affecting hospital mortality, mid- and long-term survival. Results: The hospital mortality was 6.4%. The one-, five-, and 10-year actuarial survival rates were 94%± 2%, 89%± 6%, and 81 ± 9%. New York Heart Association (NYHA) functional class IV, low left ventricular ejection fraction (<35%), increased left ventricular end-diastolic diameter (LVEDD) > 50 mm, female gender, pulmonary edema, and urgent operations were found to be risk factors in short-term survival. NYHA functional class IV, low left ventricular ejection fraction, increased LVEDD, and increased left atrial diameter (LA > 60 mm) were risk factors in mid-term survival. Conclusion: Redo mitral valve surgery with mechanical prosthesis offers encouraging short- and mid-term survival. NYHA functional class IV, low left ventricular ejection fraction, and increased left ventricular diameters were especially associated with increased short- and mid-term mortality. Earlier surgical management before the development of severe heart failure and myocardial dysfunction would improve the results of redo mitral valve surgery.  相似文献   
849.
The maintenance of telomere length is essential for the indefinite proliferation of cancer cells. This is most often achieved by the activation of telomerase; however, a substantial number of cancers lack detectable telomerase activity and are classified as using an alternative lengthening of telomeres (ALT) pathway. We showed recently that ALT cells have a high level of extrachromosomal telomeric circles (t circles) that may be a specific marker of the ALT phenotype. The mechanism underlying t circle production and the requirement of t circles in ALT remain unclear. Understanding the specific requirements of ALT is key to developing diagnostic tools and therapies that target this pathway and is critical for the treatment of cancers in which ALT is prevalent, including cancers of neuroepithelial and mesenchymal origin. In this study, we used short hairpin RNAs directed at either Xrcc3 or Nbs1, two proteins involved in the homologous recombination pathway, to determine the role of these proteins in t circle production and the requirement of t circles in maintaining the ALT pathway. We show that Xrcc3 and Nbs1 are indeed required for the production of t circles in human ALT. However, these cells continue to proliferate in the absence of t circles, suggesting that they are not required for the survival of ALT cells.  相似文献   
850.
In a retrospective analysis of 113 patients with primary myelodysplastic syndromes (MDS) diagnosed according to French-American-British (FAB) classification, we evaluated the prognostic impact of FAB and World Health Organisation (WHO) classifications, International Prognostic Scoring System (IPSS), and other clinical and laboratory variables. The median age was 69. IPSS could be applied to 75 patients classified according to the FAB criteria and to 50 patients reclassified according to the WHO criteria. At a median follow-up of 24 months, 22 patients (19.5 %) transformed to acute myelogenous leukaemia (AML). Overall survival (OS) of patients differed significantly between the FAB and WHO subgroups (p < 0.0001). In WHO classification, significant differences were observed in both OS and leukaemia free survival (LFS) between patients with RA/RARS and refractory cytopenia with multi-lineage dysplasia/refractory cytopenia with multi-lineage dysplasia and ringed sideroblasts (RCMD/RS-RCMD) (p = 0.0001). High-risk according to IPSS score and blood transfusion need were significantly predictive for a shorter survival and higher risk of transformation. Hemoglobin <10 g/dl, neutrophil count <0.5 x 10(9)/L, platelet count <50 x 10(9)/L had an unfavourable prognostic impact on survival in multi-variate analysis. Our conclusions support the previous findings on the value of WHO classification for prediction of prognosis in MDS.  相似文献   
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