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51.
The hip joint dislocation is one of the most serious complications associated with severe type of spastic cerebral palsy in children. The natural history of this secondary problem is poorly defined: how often and why the dislocated hip joint is going to be painful. The aim of our study was to specify prevalence of hip pain in the quadriplegic spastic type of cerebral palsy children with dislocated one or two hip joints. The next purpose was to establish correlation between cartilage degenerative changes and pain appearance. MATERIAL AND METHOD: The clinical study population consisted of cerebral palsy children, who presented a unilateral or bilateral dislocation of the hip joint, operated in Department of Pediatric Orthopedics during the period 2002 through 2005. Performed surgical procedures allowed us to evaluate degenerative changes of femoral head cartilage. In 45 operated hips (33 patients) we discovered that 33 had degenerative cartilage lesions which in 25 cases (75%) were associated with pain appearance. RESULTS: We observed correlation between anterior location of the femoral head lesion and pain appearance, between the size of the lesion and intensity of pain complaints and also between femoral antetorsion and magnitude of pain. CONCLUSIONS: Risk factors of pain appearance in spastic dislocated hip joint are degenerative lesions on anterior face of femoral head cartilage, age of the patient, large antetorsion angle and cartilage lesion bigger than 1/4 of femoral head surface.  相似文献   
52.
Purpose Assessment of tumor proliferation rate using Bromodeoxyuridine labeling index (BrdUrdLI) as a possible predictor of rectal cancer response to preoperative radiotherapy (RT). Methods and material Ninety-two patients were qualified either to short RT (5 Gy/fraction/5 days) and surgery about 1 week after RT (schedule I), or to short RT and 4–5 weeks interval before surgery (schedule II). Tumor samples were taken twice from each patient: before RT and at the time of surgery. The samples were incubated with BrdUrd for 1 h at 37°C, and the BrdUrdLI was calculated as a percentage of BrdUrd-labeled cells. Results Thirty-eight patients were treated according to schedule I and 54 patients according to schedule II. Mean BrdUrdLI before RT was 8.5% and its value did not differ between the patients in the two compared groups. After RT tumors showed statistically significant growth inhibition (reduction of BrdUrdLI). As the pretreatment BrdUrd LI was not predictive for early clinical and pathologic tumor response, prognostic role of the ratio of BrdUrdLI after to BrdUrdLI before RT was considered. The ratios were calculated separately for fast (BrdUrd LI > 8.5%) and slowly (BrdUrd LI ≤ 8.5%) proliferating tumors and correlated with overall treatment time (OTT, i.e., time from the first day of RT to surgery). One month after RT, accelerated proliferation was observed only in slowly proliferating tumors. Conclusions Pretreatment BrdUrdLI was not predictive for early clinical and pathologic tumor response. The ratio after/before RT BrdUrdLI was correlated to inhibition of proliferation in responsive tumors. The paper was presented at ECCO 13, October 30 to November 03, 2005 in Paris, France  相似文献   
53.
Background According to the concept of sentinel node (SN), the lymphatic pathway leading to SN should be regarded as the main and the most important lymphatic route from primary tumor to regional lymph nodes. We performed ex vivo blue-dye SN mapping in postmastectomy specimens to assess whether the main lymphatic tract leading to SN is completely removed during mastectomy. We assumed that ex vivo identification of SN may be possible only if the entire lymphatic tract leading to sentinel node is removed from within the postmastectomy specimen. Methods Blue dye (1 mL) was injected intracutaenously, periareolary into each of 28 postmastectomy specimens. In 13 cases mastectomy was performed with the use of transverse skin incision; in 15 cases oblique incision was used. Results The use of transverse skin incision during modified radical mastectomy allowed identification of the sentinel node and removal of the entire lymphatic pathway leading to sentinel node only in 4 of 15 cases (31%). Conversely, the use of oblique skin incision during modified radical mastectomy allowed identification of the sentinel node and removal of the entire lymphatic pathway leading to sentinel node in 12 of 15 cases (80%). Conclusions Our experiment revealed that the use of transverse skin incision during modified radical mastectomy may not be the best choice for breast cancer patients. In our opinion, this observation may be especially important for patients not irradiated postoperatively.  相似文献   
54.
OBJECTIVE: The surgical treatment of aortoesophageal fistulae (AEF) has a high morbidity and mortality rate. We report our experience with the sequential use of endovascular thoracic stentgrafts and cryopreserved aortic homografts for in situ repair of the descending thoracic aorta. METHODS: In a 7-year period, 6 patients with AEF were treated at our center. After primary endovascular repair in all cases, 4 patients subsequently underwent in situ repair of the descending thoracic aorta with cryopreserved homografts. Long-term antibiotic therapy was given in all cases. Recent clinical status and radiologic findings on follow-up studies of each patient were analyzed. The mean follow-up time was 35 months (range, 2-76). RESULTS: Endovascular stentgraft repair was technically successful in all cases. Two patients were not candidates for open surgical repair because of their medical condition; they both died within 8 weeks after discharge from the hospital, 1 from recurrent septic episodes, and the other from upper gastrointestinal bleeding. One of 4 patients who had undergone open surgical repair died 1 year later from upper gastrointestinal bleeding that occurred presumably due to an infectious degeneration of the homograft after secondary infection with a methacillin-resistant Staphyloccocus aureus. In 1 case persistent paraplegia and in another case persistent renal failure occurred. CONCLUSION: The use of cryopreserved homografts is a valuable alternative to in situ repair with prosthetic vascular grafts or extra-anatomic reconstructions in the surgical treatment of AEF. Endovascular stentgraft placement plays a role as a bridging procedure in emergency situations.  相似文献   
55.
The aim of this study was to prospectively investigate the spermatozoa ultrastructure in relation to the results of in vitro fertilization-embryo transer (IVF-ET). Forty-nine consecutive couples admitted for IVF-ET were prospectively evaluated for electron microscopic spermatozoa morphology and the outcome of IVF-ET. Thirty-four couples revealed successful fertilization, defined as presence of two pronuclei 14-16 hours after spermatozoa administration, while the remaining 15 formed the failure group. Spermatozoa fixed with 2.5% glutaraldehyd and embedded in Spurr's resin were analyzed with JAM 100 S transmission electron microscope (TEM) for the following ultrastructure abnormalities: head deformity, cytoplasmic residues, chromatin condensation failures, acrosomal alterations, neck defects, mid-piece defects, principal piece and end-piece defects and immature forms. Successful IVF-ET couples revealed a significantly higher percentage of normal spermatozoa utrastructure (32.0 +/- 13.1% versus 17.1 +/- 13.4%, p < 0.001). Failed IVF-ET couples represented a significantly higher percentage of chromatin condensation failures (9.8 +/- 5.1% versus 5.7 +/- 5.3%, p < 0.05) and tail defects (16.7 +/- 11.5% versus 7.2 +/- 7.2%, p < 0.001). A positive correlation between normal ultrastructure spermatozoa percentage and fertilized oocytes percentage was found (r = 0.35, p < 0.05). Our data suggest that spermatozoa TEM findings correlate with IVF-ET results. Ultrastructural estimation of spermatozoa can improve the diagnosis of male fertility and may explain some reasons of failure in assisted reproduction methods. We consider systematic TEM spermatozoa examination in cases with failed IVF-ET prior to intracytoplasmic sperm injection (ICSI).  相似文献   
56.
57.
There are limited clinical data regarding prolonged‐release tacrolimus (PR‐T) use in pediatric transplant recipients. This Phase 2 study assessed the efficacy and safety of PR‐T in stable pediatric kidney, liver, and heart transplant recipients (aged ≥5 to ≤16 years) over 1 year following conversion from immediate‐release tacrolimus (IR‐T), on a 1:1 mg total‐daily‐dose basis. Endpoints included the incidence of acute rejection (AR), a composite endpoint of efficacy failure (death, graft loss, biopsy‐confirmed AR, and unknown outcome), and safety. Tacrolimus dose and whole‐blood trough levels (target 3.5–15 ng/ml) were also evaluated. Overall, 79 patients (kidney, n = 48; liver, n = 29; heart, n = 2) were assessed. Following conversion, tacrolimus dose and trough levels remained stable; however, 7.6–17.7% of patients across follow‐up visits had trough levels below the target range. Two (2.5%) patients had AR, and 3 (3.8%) had efficacy failure. No graft loss or deaths were reported. No new safety signals were identified. Drug‐related treatment‐emergent adverse events occurred in 28 patients (35.4%); most were mild, and all resolved. This study suggests that IR‐T to PR‐T conversion is effective and well tolerated over 1 year in pediatric transplant recipients and highlights the importance of therapeutic drug monitoring to maintain target tacrolimus trough levels.  相似文献   
58.
PURPOSE: Liquid sources of radiation delivered in angioplasty balloons may be a convenient self-centering device used for prevention of in-stent restenosis. To test the effectiveness of this method an intravascular brachytherapy study was performed using 32P liquid sources in an animal model. METHODS: The radial dose distribution around angioplasty balloons filled with solutions of Na 2H 32PO 4 was calibrated by thermoluminescence dosimetry. The animal experiments were performed in rabbits with induced hypercholesterolemia. The balloons containing 32P were introduced into iliac arteries immediately after stent implantation. Estimated 7-49 Gy doses required 30-100 min irradiations. Radiation effects were evaluated by comparing the thickness of various components of the artery wall. RESULTS: Doses of 7, 12, 16 or 49 Gy on the internal artery surface required 30-100 min of irradiation. The dose of 49 Gy at "zero" distance corresponding to 16 Gy at 1.0 mm from the balloon surface reduced hypertrophy in every layer of the arterial wall: in the intima the cross-sectional areas were 0.13 versus 0.91 mm 2, in the media were 0.5 versus 0.46 mm 2 and in the adventitia were 0.04 versus 0.3 mm 2 (p <0.05). A dose of 7 Gy at the balloon surface produced adverse irradiation effects: the intimal area of the artery was 2.087 versus 0.857 mm 2, the medial area was 0.59 versus 0.282 mm 2 and the adventitial area was 0.033 versus 0.209 mm 2 in treated and control arteries, respectively. CONCLUSION: Application of a 49 Gy irradiation dose to the internal arterial surface effectively prevented in-stent restenosis.  相似文献   
59.
OBJECTIVE: Low molecular weight heparins (LMWHs) offer practical and potential pharmacological advantages over unfractionated heparin in multiple applications but have not been studied as vasoactive agents. The purpose of this study was to investigate the effects of two commercial preparations of LMWHs, enoxaparin sodium and nadroparin calcium, on vasoconstriction in the human internal thoracic artery (ITA) in vitro. METHODS: Samples of redundant ITA segments obtained from 36 patients who underwent coronary artery bypass surgery were cut into 3mm wide rings and suspended in 20 ml organ bath. Activity of ITA rings precontracted with 80 mM KCl, 0.1 microM endothelin-1 (ET-1) and 1 microM norepinephrine (NE) after administration of enoxaparin and nadroparin in accumulative concentration ranging from 0.1 to 13.2 UI AXa/ml were recorded under isometric conditions by means of force transducers with digital output. The contraction after 80 mmol KCl, 0.1 microM ET-1 and 1 microM NE administration was treated as a control. RESULTS: Both studied LMWHs in concentration ranging from 0.12 to 13.2 UI AXa/ml did not change basal tonus and KCl precontracted ITA rings. When used in concentrations higher than 13.2 UI AXa/ml nadroparin but not enoxaparin significantly increased the tension in KCl precontracted arterial rings. In NE and ET-1 precontracted rings enoxaparin and nadroparin caused dose dependent relaxation without significant differences between both preparations. Incubation with nitric oxide blocker-Nomega-NITRO-L-ARGININE (L-NNA) in concentration 0.2 mM caused a significant attenuation of relaxant responses to both studied LMWHs in NE and ET-1 precontracted rings. CONCLUSION: LMWHs can have vasorelaxant effects on the receptor-mediated ITA vasoconstriction. The results suggest that LMWHs-induced relaxation in the human ITA is at least partially caused by nitric oxide release. Although the vasoactive effects are not the primary advantage of these drugs used as antithrombotics, such effects might have some clinical importance in the treatment and prophylaxis of graft spasm.  相似文献   
60.
A series of 54 patients is presented in which full-thickness soft-tissue defects on 57 digits were reconstructed using homodigital V-Y flaps. This is a modification of the Moberg procedure, which was designed for coverage of injuries of distal thumb. The V-Y flap is pedicled on two digital neurovascular bundles, possible advancement is up to 2 cm, and V-shaped base of the flap allows direct closure of the proximal defect, without skin grafting. This technique was used for the reconstruction both volar and dorsal tissue defects of the fingers. All flaps healed within 2-4 weeks. 14 patients (15 fingers) were evaluated after they recovered. In all affected fingers active range of motion was satisfactory, only with slight defect of extension in 2 cases. However, sensation of the light touch was decreased in 10 fingers, and 2PD discrimination was abnormal in 5 fingers. The versatility of V-Y technique in various clinical occasions and its low risk of complications was emphasized. This method is very useful, easy to learn even for trainees unfamiliar with microsurgery.  相似文献   
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