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101.
OBJECTIVE: The diagnosis of early local recurrence of soft tissue sarcomas, especially in those treated with surgery and radiotherapy, is a difficult clinical problem. Financial constraints led us to use ultrasonography instead of CT or MR imaging. The aim of this study was to evaluate the role of ultrasonography (US) in detecting local recurrence. METHODS AND RESULTS: Fifty patients with previous treatment for soft tissue sarcomas were evaluated prospectively for recurrence by US and histopathology. Seven of the 50 patients were clinically suspected to have recurrent tumour. Ultrasonography showed recurrence in 26, no recurrence in 18, benign disease in four and was indeterminate in two cases. Ultrasonography was instrumental in guiding fine needle aspiration biopsies of small local recurrences and indeterminate lesions in 17 patients. In the sonographically tumour positive patients, histopathology confirmed recurrence in 24; one case had benign disease and one patient refused surgery. Thirteen of the 18 sonographically tumour negative patients were operated upon; all were negative for tumour on histopathology. Both the indeterminate cases showed recurrence on histopathology. The benign cases were confirmed by histopathology correlation. Ultrasound guided fine needle aspiration cytology (FNAC) was positive in 14 out of 17 patients (88%). The sensitivity and specificity of US was 92.30% and 94.4% respectively. CONCLUSION: Our study concludes that US is an extremely useful and cost effective method in the detection of early local recurrences of soft tissue sarcomas and should therefore be used for initial routine follow-up and guided biopsies.  相似文献   
102.
Vasectomy results in the occlusion of testicular outflow, leading to autoimmunity characterized by the production of antisperm antibodies (ASA). Reports on the rise in ASA following vasectomy in several species are available; however, not much is known about the specific sperm autoantigens to which postvasectomy antibodies are directed. In the present study, monoclonal antibodies were generated using a vasectomized mouse. One of the monoclonal antibodies, D5E5, identified an approximately 70-kd antigen localized on the principal piece of the tail and also on the tip of the acrosome of mouse sperm. The cognate antigen was expressed postmeiotically in a stage-specific manner during spermiogenesis, starting from step 8 of elongating spermatids during spermiogenesis up to mature spermatozoa. The protein was conserved across the species, as observed by its presence in rat, bull, marmoset, and human sperm. Following capacitation, the antigen on the head was seen to shift to the acrosomal region and was lost after the acrosome reaction. However, the localization on tip of the acrosome still persisted, which indicates that the antigen may play a role post-acrosome reaction in sperm egg interaction. Resistance to Triton X-100 solubilization indicates that TSA70 could be an acrosomal matrix protein. In addition, we observed a significant reduction in forward progressive motility of mouse sperm treated in vitro with D5E5. In view of its testis specificity, acrosome and tail localization, and conserved nature, TSA70 is likely to play an important role in sperm function.  相似文献   
103.
Introduction In a low risk procedure like ASD closure Right Posterolateral thoracotomy approach aims at the cosmetic results as compared to median sternotomy. This paper illustrates our approach for a standardised Right Posterolateral thoracotomy in ostium secundum ASD repair and the analysis of the outcome. Methods Right Posterolateral thoracotomy (RPLT) was offered as a cosmetic alternative for atrial septal defect (ASD) closure in children, and selected adult patients below 30 years with lean body build. A retrospective study comparing these patients with median sternotomy approach during the same period (2000–2003) was performed. Exclusion criteria included preoperative diagnosis of complex ASD, obesity and chest wall deformity. Common variables were considered for analysis. Results There were 96 patients (66 females and 30 males) with an average age of 13yrs (range 3 to 27 years) in RPLT group and 225 patients (95 females and 130 males) with average age of 36 years (range 2 to 46 years) in sternotomy group. Extra corporeal time was 32 minutes (28 to 45) and aortic cross clamp time was 14 minutes (8 to 36) in RPLT while the values were 46 minutes (37 to 90) and 22 minutes (18 to 36) in Median sternotomy approach. Blood loss in postoperative period was 160 ml (20 ml to 400 ml) in thoracotomy group compared to 210 ml (40ml to 600 ml) in sternotomy group. There was no mortality or recurrence after repair of ASD during the follow-up. Significant postoperative morbidity was persisting pain and shoulder movement restriction in 12 patients. The scar was cosmetic in RPLT. Conclusion In selected patients with lean body build Right posterolateral thoracotomy is suitable for ostium secundum atrial septal defect closure. The final appearance has definite cosmetic advantage over sternotomy. Presented at the 50th Annual Meeting of IACTS, New Delhi, Feb., 2004.  相似文献   
104.
105.
The availability of lumbar interbody cages has fuelled renewed interest in interbody fusion. Despite this, there is no consensus regarding the best non-invasive method for evaluation of interbody fusion, especially where cages have been used. The purpose of this study was to determine whether high-quality thin-slice (1- to 3-mm) computed tomography (CT) scans allow proper evaluation of interbody fusion through titanium cages. Patients undergoing lumbar interbody fusion were prospectively evaluated with CT scan and plain radiographs 6 months following surgery. These images were blindly and independently evaluated by a consultant radiologist and a spine research fellow, for bridging bony trabeculation both through and surrounding the cages as well as for changes at the cage endplate interface. Fifty-three patients (156 cages) undergoing posterior lumbar interbody fusion using titanium interbody cages were evaluated. Posterior elements were used to pack the cages and no graft was packed outside the cages. The outcome data were analysed using the Kappa co-efficient and chi-squared analysis. On CT scan, both observers noted bridging trabeculation in 95% of the cages (Kappa 0.85), while on radiographs this was present in only 4% (Kappa 0.74). Both observers also identified bridging trabeculation surrounding the cages on CT scan in 90% of cages (Kappa 0.82), while on the radiographs this was 8% (Kappa 0.86). Radiographs also failed to demonstrate all the loose cages. The results of the study show that high-quality CT scans show images suggesting bridging bony trabeculae following the use of titanium interbody cages. They also appear to show consistent bone outside the cages in spite of no bone graft having been used, and they appear to be better than plain radiographs in the early detection of cage loosening.  相似文献   
106.
Hypercalciuria is the most common risk factor for kidney stones and has a recognized familial component. The genetic hypercalciuric stone-forming (GHS) rat is an animal model that closely resembles human idiopathic hypercalciuria, with excessive intestinal calcium absorption, increased bone resorption, and impaired renal calcium reabsorption; overexpression of the vitamin D receptor (VDR) in target tissues; and calcium nephrolithiasis. For identifying genetic loci that contribute to hypercalciuria in the GHS rat, an F2 generation of 156 rats bred from GHS female rats and normocalciuric WKY male rats was studied. The calcium excretion was six- to eightfold higher in the GHS female than in the WKY male progenitors. Selective genotyping of those F2 rats with the highest 30% and lowest 30% rates of calcium excretion was performed, scoring 98 markers with a mean interval of 23 cM across all 20 autosomes and the X chromosome. With the use of strict criteria for significance, significant linkage was found between hypercalciuria and a region of chromosome 1 at D1Rat169 (LOD, 2.91). Suggestive linkage to regions of chromosomes 4, 7, 10, and 14 was found. The proportion of phenotypic variance contributed by the region on chromosome 1, with appropriate adjustments, was estimated to be 7%. Candidate genes encoding the VDR and the calcium-sensing receptor were localized to regions on rat chromosomes 7 and 11, respectively, but the suggestive quantitative trait locus on chromosome 7 was not in the region of the VDR gene locus. Identification of genes that contribute to hypercalciuria in this animal model should prove valuable in understanding idiopathic hypercalciuria and kidney stone disease in humans.  相似文献   
107.
OBJECTIVES: There is an absence of prospective data evaluating the impact of prehospital intubation in adult trauma patients. Our objectives were to determine the outcome of trauma patients intubated in the field who did not have an acutely lethal traumatic brain injury (death within 48 hours) compared with patients who were intubated immediately on arrival to the hospital. METHODS: Prospective data were collected on 191 consecutive patients admitted to the trauma center with a field Glasgow Coma Scale score < or = 8 and a head Abbreviated Injury Scale score > or = 3 who were either intubated in the field or intubated immediately at admission to the hospital. Patients who died within 48 hours of admission and transfers were excluded from the study. RESULTS: Of the 191 patients, 176 (92%) sustained blunt trauma and 25 (8%) were victims of penetrating trauma. Seventy-eight (41%) of the 191 patients were intubated in the field and 113 (59%) were intubated immediately at admission. There was no significant difference in age, Glasgow Coma Scale score, head Abbreviated Injury Scale score, or Injury Severity Score between the two groups. Patients who were intubated in the field had a significantly higher morbidity (ventilator days, 14.7 vs. 10.4; hospital days, 20.2 vs. 16.7; and intensive care unit days, 15.2 vs. 11.7) compared with patients intubated on immediate arrival to the hospital and nearly double the mortality (23% vs. 12.4). Field-intubated patients had a 1.5 times greater risk of nosocomial pneumonia compared with hospital-intubated patients. CONCLUSION: Prehospital intubation is associated with a significant increase in morbidity and mortality in trauma patients with traumatic brain injury who are admitted to the hospital without an acutely lethal injury. A randomized, prospective study is warranted to confirm these results.  相似文献   
108.
PURPOSE: To quantify the changes in brain water diffusivity in hepatic encephalopathy (HE) associated with cirrhosis using diffusion tensor imaging (DTI) and to correlate with neuropsychological (NP) scores. MATERIALS AND METHODS: DTI was performed in 14 patients with low-grade HE and age/gender-comparable 16 healthy controls. Whole brain mean diffusivity (MD) and fractional anisotropy (FA) maps were calculated, normalized to common space, smoothed, and compared voxel-by-voxel between groups using analysis of covariance with age included as a covariate. The average MD and FA values were also calculated from individual subjects for selected brain regions and correlated with the neuropsychological scores. RESULTS: Patients with HE showed increased MD in the cortical gray and white matter and the internal capsule. Less extensive brain regions with decreased FA were observed in the bilateral frontal and occipital white matter. MD values from the corpus callosum correlated inversely with several NP scores among HE patients and controls. Positive correlations were observed with FA values and cognitive scores. CONCLUSION: Voxel-based DTI analysis showed widespread brain regions with increased MD values, indicating enhanced water content and decreased FA in cirrhotic patients with HE. The MD and FA values from selected regions correlated with the NP scores.  相似文献   
109.
BACKGROUND: The management of hormone-insensitive locally advanced prostate cancer is difficult and complex and there is an urgent need for the development of effective chemotherapeutic agents intended for combination with currently available treatment modalities. METHODS: The present paper demonstrates the effectiveness of the monoterpene perillyl alcohol (POH) as potent radiosensitizer on DU145 and PC3 cell lines by performing clonogenic survival assays, cycle analysis, and assays to detect viability, apoptosis, and Fas receptor/ligand by flow cytometry. RESULTS: POH pretreatment resulted in a dose dependent sensitization to kill cell by radiation. Furthermore, POH treatment induced a transient G(2)/M arrest, enhanced the expression of the membrane bound form of the Fas ligand and sensitized the cells to Fas mediated apoptosis. CONCLUSIONS: The unique manner of radiosensitization in addition to its low toxicity profile makes POH a promising new agent for preclinical evaluation as a potential radiosensitizer in the treatment of prostate cancer.  相似文献   
110.
The aim of a surgical residency program is to produce competent professionals displaying the cognitive, technical, and personal skills required to meet the needs of society. Current changes to the delivery of healthcare necessitate the development of new models of training. These can be supported with the development of new technologies to train and assess surgical practitioners. This article describes recent developments within Imperial College London with regard to eye tracking, noninvasive brain imaging, and an innovative mentoring scheme for the new surgical curriculum. The concept of eye tracking is described, together with surgical application for this technique in terms of dexterity analysis during minimally invasive procedures. We have also begun to understand spatial localization within the brain cortex during surgical knot-tying tasks. The aim is to develop a map of the cortex with regard to surgical novices and experienced surgeons and then to develop the hypothesis that a translational process of cortical plasticity occurs during training. Finally, the article is intended to describe a training scheme that goes beyond dexterity, and moves toward the development of a successful surgeon through surgical mentoring. It is hoped that some of these tools will enhance the training of future surgeons in order to continue to provide a high-quality service to our patients.  相似文献   
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