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61.
Nephron-sparing surgery is currently the standard of care for the management of small renal masses. While both neoadjuvant and adjuvant conventional external beam radiotherapy have failed to demonstrate an oncologic benefit for the treatment of renal cell carcinoma, more recent work aims to explore the utility of stereotactic radiotherapy. We present the case of a 70-year-old woman who failed primary treatment of a small renal mass with the CyberKnife radiotherapy system and describe her successful salvage treatment with robot-assisted partial nephrectomy. This case demonstrates the safety of robotic surgery for the management of renal tumors following failed stereotactic radiotherapy.  相似文献   
62.
ABSTRACT: BACKGROUND: Foot deformities and related problems of the forefoot are very common in patients with rheumatoid arthritis. The laxity of the medial cuneometatarsal joint and its synovitis are important factors in the development of forefoot deformity. The impaired joint causes the first metatarsal bone to become unstable in the frontal and sagittal planes. In this retrospective study we evaluated data of patients with rheumatoid arthritis who underwent Lapidus procedure. We evaluated the role of the instability in a group of patients, focusing mainly on the clinical symptoms and X-ray signs of the instability. METHODS: The study group included 125 patients with rheumatoid arthritis. The indications of the Lapidus procedure were a hallux valgus deformity greater than 15 degrees and varus deformity of the first metatarsal bone with the intermetatarsal angle greater than 15 degrees on anterio-posterior weight-bearing X-ray. RESULTS: Data of 143 Lapidus procedures of 125 patients with rheumatoid arthritis, who underwent surgery between 2004 and 2010 was evaluated. Signs and symptoms of the first metatarsal bone instability was found in 92 feet (64.3 %) in our group. The AOFAS score was 48.6 before and 87.6 six months after the foot reconstruction. Nonunion of the medial cuneometatarsal joint arthrodesis on X-rays occurred in seven feet (4.9 %). CONCLUSION: The Lapidus procedure provides the possibility to correct the first metatarsal bone varus position and its instability, as well as providing the possibility to achieve a painless foot for walking. We recommend using the procedure as a preventive surgery in poorly symptomatic patients with rheumatoid arthritis in case of the first metatarsal bone hypermobility.  相似文献   
63.
BACKGROUND: Ionizing radiation is the strongest risk factor known for the development of thyroid neoplasia. While previous studies have demonstrated a high prevalence of ret/papillary thyroid cancer (PTC) activation in cohorts of patients developing thyroid nodules after childhood exposure to ionizing radiation, no study has directly compared ret/PTC activation with individual estimates of radiation dose to the thyroid. This study combines individual thyroid dosimetry data with molecular analysis of surgically removed thyroid nodules in order to determine if ret/PTC activation in thyroid nodules is associated with increasing estimated radiation dose from Chernobyl. METHODS: This pilot study included adults and children diagnosed with PTC (n = 76) and children diagnosed with follicular adenomas (n = 24) during May 1986 through December 1999, who were living in the Bryansk Oblast of the Russian Federation at the time of the Chernobyl accident, who had paraffin-embedded thyroid surgical samples available and for whom an individual dose to the thyroid could be estimated. The frequency of ret/PTC activation was determined using RT-PCR analysis. Individual radiation doses to the thyroid were estimated using a semiempirical model, and data were collected by detailed interview, primarily of the participant's mother. RESULTS: ret/PTC oncogene activation was detected in 23.8% (5/21) and 14.5% (8/55) of the childhood and adult PTC cases, respectively, and 8.3% (2/24) of the follicular adenoma cases. No statistically significant differences were noted in age at the time of exposure or diagnosis, gender, latency period, or estimated radiation dose between PTC patients with or without ret/PTC activation. Further, no significant dose-response relationship was detected among PTC patients with ret/PTC activation. CONCLUSIONS: Factors other than individual thyroid radiation doses may influence the development and subsequent detection of ret/PTC oncogene activation in radiation related PTC arising in the Bryansk Oblast of the Russian Federation in the aftermath of the Chernobyl accident.  相似文献   
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65.
ObjectiveThe predisposing factors for pericarditis recurrence in the pediatric population have not yet been established. This study aimed to define the risk factors for the unfavorable prognosis of pediatric acute pericarditis.MethodsThis was a retrospective study that included all patients with acute pericarditis treated from 2011 to 2019 at a tertiary referent pediatric center.ResultsThe study included 72 children. Recurrence was observed in 22.2% patients. Independent risk factors for recurrence were: erythrocyte sedimentation rate  50 mm/h (p = 0.003, OR 186.3), absence of myocarditis (p = 0.05, OR 15.2), C-reactive protein  125 mg/L (p = 0.04, OR 1.5), and non-idiopathic etiology pericarditis (p = 0.003, OR 1.3). Corticosteroid treatment in acute pericarditis was associated with a higher recurrence rate than treatment with non-steroid anti-inflammatory therapy (p = 0.04). Furthermore, patients treated with colchicine in the primary recurrence had lower recurrence rate and median number of repeated infections than those treated without colchicine (p = 0.04; p = 0.007, respectively).ConclusionIndependent risk factors for recurrence are absence of myocarditis, non-idiopathic etiology pericarditis, C-reactive protein  125 mg/L, and erythrocyte sedimentation rate  50 mm/h. Acute pericarditis should be treated with non-steroid anti-inflammatory therapy. A combination of colchicine and non-steroid anti-inflammatory drugs could be recommended as the treatment of choice in recurrent pericarditis.  相似文献   
66.
PURPOSE: The purpose of this study was to identify the contribution of ingested lead particles to elevated blood lead concentrations in victims of gunshot injury to the maxillofacial region. PATIENTS AND METHODS: As part of a larger study of the effects of retained lead bullets on blood lead, a retrospective review of study findings was completed on 5 of 8 patients who sustained injuries to the maxillofacial region. These 5 patients were recruited into the larger study within 11 days of injury and showed a penetration path for the projectile that engaged the upper aerodigestive tract. All subjects were recruited from patients presenting for care of their gunshot injuries to a large inner-city trauma center with a retained bullet resulting from a gunshot injury. An initial blood lead level was measured for all recruited patients and repeated 1 to 17 weeks later. Medical history was taken along with a screening and risk factor questionnaire to determine other potential or actual sources (occupational/recreational) of lead exposure. (109)Cd K-shell x-ray fluorescence determinations of bone lead were completed to determine past lead exposure not revealed by medical history and risk factor questionnaire. Radiographs taken of the abdomen and chest, required as a part of the patient's hospital care, were retrospectively reviewed for signs of metallic fragments along the aerodigestive tract. RESULTS: All 5 patients retained multiple lead pellets or fragments at the site of injury, sustained fractures of the facial bones, and showed increases in blood lead. Three of the 5 study subjects who sustained maxillofacial gunshot injuries involving the mouth, nose, or throat region showed metallic densities along the gastrointestinal tract indicative of ingested bullet fragments. Each patient with ingested bullet fragments showed rapid elevation of blood lead exceeding 25 microg/dL and sustained increases well beyond the time when all ingested fragments were eliminated. A 3-year follow-up on these 3 patients showed significantly sustained elevation of blood lead but less than that observed during the initial 6 months after injury. None of the 5 study subjects showed any evidence of metallic foreign bodies within the tracheobronchial regions indicative of aspiration. CONCLUSION: Ingestion of lead fragments can result from gunshot injuries to the maxillofacial region and may substantially contribute to a rapid increase in blood lead level. Prompt diagnosis and elimination of ingested lead fragments are essential steps necessary to prevent lead being absorbed from the gastrointestinal tract. Increased blood lead in victims after gunshot injuries must be fully evaluated for all potential sources, including recent environmental exposure, absorption of lead from any remaining bullets in body tissues, and the possibility of mobilization of lead from long-term body stores such as bone.  相似文献   
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68.
Imidazole (0.73-15.9mM) was found to increase both tension developed Td and the maximum rats of rise of tension, dT/dtmax, in the isolated hemidiaphragm of the rat during indirect stimulation. Similar effects were obtained during direct stimulation and in the presence of d-tubocurarine. Imidazole (0.73-22 mM) antagonized the action of d-tubocurarine. This effect was particularly pronounced in preparations pretreated with imidazole. Propranolol did not significantly change the action of imidazole on Td and dT/dtmax during direct stimulation. Similarly, propranolol did not affect the action of low concentrations of imidazole during indirect stimulation. When present in the bath for periods of time longer than 15 min, propranolol significantly depressed the effect of even high concentrations of imidazole on Td and dT/dtmax during indirect stimulation. Histamine (0.18-0.91 mM) did not affect either Td or dT/dtmax. In the experiments in vivo, imidazole (12.5-100 mg/kg) produced a small increase both in Td and dT/dtmax of the gastrocnemius muscle during sciatic nerve stimulation. The available evidence indicates that the action of imidazole on Td and dT/dtmax is not connected with its action on phosphodiesterase, but it is most probably due to a direct action on the muscle.  相似文献   
69.
Intravascular cancer cell adhesion plays a significant role in the metastatic process. Studies indicate that galectin-3, a member of the galectin family of soluble animal lectins, is involved in carbohydrate-mediated metastatic cell heterotypic (between carcinoma cells and endothelium) and homotypic (between carcinoma cells) adhesion via interactions with the tumor-specific Thomsen-Friedenreich glycoantigen (TFAg). We hypothesized that blocking the galectin-3 carbohydrate recognition domain with synthetic peptides would significantly reduce metastasis-associated carcinoma cell adhesion. To test this hypothesis, we identified peptide antagonists of the galectin-3 carbohydrate recognition domain using combinatorial bacteriophage display technology. The peptides bound with high affinity to purified recombinant galectin-3 protein (K(d) approximately 17-80 nM) and to cell surface galectin-3. Experiments with a series of recombinant serially truncated galectin-3 mutants indicated that the peptides bound the carbohydrate recognition domain of galectin-3. Furthermore, the peptides did not bind the carbohydrate recognition domain of other galectins and plant lectins. Synthetic galectin-3 carbohydrate recognition domain-specific peptides blocked the interaction between galectin-3 and TFAg and significantly inhibited rolling and stable heterotypic adhesion of human MDA-MB-435 breast carcinoma cells to endothelial cells under flow conditions, as well as homotypic tumor cell aggregation. These results demonstrate that carbohydrate-mediated, metastasis-associated tumor cell adhesion could be inhibited efficiently with short synthetic peptides which do not mimic naturally occurring glycoepitopes yet bind to the galectin-3 carbohydrate recognition domain with high affinity and specificity.  相似文献   
70.
PURPOSE: To determine the efficacy and safety of surgical implantation of artificial iris-lens diaphragm in patients with anatomic or functional iris deficiencies, aphakia or cataract. SETTING: Svyatoslav Fyodorov MNTK Eye Microsurgery, Cheboksary, Russia. METHODS: Twenty eyes of 19 consecutive patients with combined iris and lens pathology of traumatic or congenital etiology were identified for an interventional noncomparative case series. The newly proposed model of an elastic iris-lens diaphragm with a colored haptic and additional support elements was implanted using various fixation approaches. RESULTS: Fifteen eyes (75%) experienced improvement in corrected visual acuities. The best spectacle-corrected visual acuity (BSCVA) in 2 eyes did not change, while the uncorrected visual acuity (UCVA) in these eyes increased. There were 3 eyes in which BSCVA deteriorated with no change or even slight improvement in UCVA. All patients were satisfied with the cosmetic results of the surgery and reported a decrease in glare and photophobia. There was 1 intraoperative complication of vitreous hemorrhage. Postoperatively, 2 cases of hyphema, 1 case of ciliochoroidal detachment, 4 eyes with exaggerated immediate postoperative reaction, and 1 eye with persistent low-grade cyclitis were observed. In 1 eye, there was persistent intraocular pressure rise. One eye showed signs of cystoid macular edema. No iris-lens diaphragm decentrations and no new or extensions of old retinal detachments were seen during the follow-up period. CONCLUSIONS: Artificial iris-lens diaphragm implantation effectively improved postoperative outcomes by correcting aphakia, reducing glare disability, and addressing cosmetic issues faced by iris-deficient, and aphakic or cataract patients. Although the iris-lens diaphragm appears to be safe, long-term results must be clarified in studies with longer follow-up and a larger patient population.  相似文献   
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