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991.

INTRODUCTION

The NHS Cancer Plan was introduced in 2000 and included guidelines for the rapid assessment and referral of cases of suspected malignancy. We wished to assess the efficiency and appropriateness of patients referred under the Department of Health''s general practitioner referral guidelines implemented for sarcomas in December 2000.

PATIENTS AND METHODS

A retrospective case-note review was performed of all patients referred to our regional soft tissue sarcoma unit between 1 January 2004 and 31 December 2008. Patients referred under the two-week guidelines and all patients referred routinely were analysed. The main outcome measures were the total number of patients referred on the basis of the two-week guidelines and the proportion they constitute of all referrals. The referring criteria were noted and compared to the observed criteria recorded. The final histo-logical diagnosis of patients referred on the basis of the two-week guidelines are documented.

RESULTS

A total of 2746 referrals for suspected sarcoma were made from January 2004 to December 2008. Of these, 154 referrals were made under the two-week rule of which 102 were referred purely on the clinical criteria for suspected soft tissue sarcoma. The remaining patients were referred after non-urgent special investigations indicated the possibility of sarcoma. Twelve patients referred under the two-week rule were proved to have sarcoma, nine after specific investigations including imaging or histological diagnosis. Of the 102 patients referred on clinical suspicion of a sarcoma, two patients had proven soft tissue sarcomas and one patient a cutaneous sarcoma. Between 2004 and 2008, the number of 2-week referrals rose 25-fold but accounted for an increase of less than 1% of the sarcomas treated in this unit.

CONCLUSIONS

The numbers of all referrals for suspected sarcoma are increasing; however, the rate of increase of 2-week referrals is increasing faster than routine referrals and will exceed it in 2012 if current trends continue. There has not been a commensurate rise in the detection of sarcoma or, more specifically, diagnosis of the deep sarcomas associated with worse prognosis. Current clinical guidelines have essentially had no impact on the early diagnosis and treatment of soft tissue sarcoma, and may negatively impact on the treatment of patients with proven sarcoma by delaying treatment within a regional centre because of redirection of a large number of patients with benign abnormalities to such centres.  相似文献   
992.
To gain beneficial effects in the management of high-risk prostate cancer, an integrated approach that combines local therapy and androgen deprivation therapy (ADT) was used. We compared biochemical responses between primary cryosurgical ablation of the prostate (CSAP) combined with prolonged ADT and radiation combined with ADT, which is the established modality in high-risk disease. A total of 33 high-risk patients received CSAP combined with ADT for 3 months before and up to 24 months after treatment. This patient group was matched with another 33 patients who had undergone three-dimensional conformal radiation therapy (3D-CRT) with the same protocol for ADT. Biochemical recurrence (BCR) was assessed by the American Society for Therapeutic Radiation Oncology (ASTRO) definition, the Phoenix definition and a prostate-specific antigen (PSA) cutoff of 0.5 ng mL^-1. Median follow-up was 61.0 ± 11.9 months for the CSAP + ADT group and 86.0±15.8 months for the 3D-CRT + ADT group. In the CSAP group, major complications including rectourethral fistula and incontinence were not noted. In the CSAP + ADT group, 57.0% had BCR using the ASTRO definition, 21.2% using the Phoenix definition and 54.5% using a PSA cutoff of 0.5 ng mL^-1. In the 3D-CRT + ADT group, 54.5%, 21.2% and 54.5% had BCR using the ASTRO, Phoenix and PSA definition, respectively. In the CSAP + ADT group, the BCR-free survival (BRFS) was 54 ± 10 months using the ASTRO definition, 65 ± 5 months using the Phoenix definition and 51 ± 4 months using a PSA cutoff of 0.5 ng mL-1. In the 3D-CRT + ADT group, the BRFS was 68 ± 12, 93 ± 19 and 70 ± 18 months using the ASTRO, Phoenix and PSA definition, respectively. By the log-rank test, the BRFS values for each group were not statistically different. This intermediate-term result indicated that primary CSAP combined with prolonged ADT offers a parallel biochemical response compared with radiotherapy in high-risk prostate cancer.  相似文献   
993.
The aim of the current study was to test the independent and joint contributions of 8 different types of trauma to posttraumatic stress disorder (PTSD) risk using data from a young adult female cohort. Associations of traumatic events with PTSD onset were examined using Cox proportional hazards models. Differences in risk as a function of age at trauma were tested. Childhood sexual assault, physical abuse, and neglect were stronger predictors of PTSD onset than adolescent and early adult occurrence of these events in individual models. In a model including all traumatic events, differential risk by age remained for sexual assault and physical abuse. Early sexual assault was the strongest predictor of risk, but additional traumatic events increased risk even in its presence.  相似文献   
994.
Midfoot osteoarthritis (OA) is a degenerative condition of the foot that can be treated non-operatively by the use of orthotics. This prospective study was conducted to determine the effects of custom-made semi-rigid foot orthoses (FOs) and rigid carbon fibre (CF) footplates for the treatment of midfoot OA evaluated using specifically designed questionnaires. Fifty-seven subjects diagnosed with midfoot OA were recruited through a private clinic for inclusion in the study. Subjects were required to complete pre-treatment questionnaires prior to receiving orthotic treatment. All subjects received a pair of custom-made full-length semi-rigid FOs and 36 subjects also received CF footplates that were incorporated into the soles of the shoes worn on the symptomatic feet. Subjects completed post-treatment questionnaires at six weeks, three months and six months after receiving the orthotic treatment. The results demonstrated that there were no significant differences between the results of the subjects who received CF footplates and those who did not. The results of the questionnaires demonstrated that subjects experienced significant improvements in pain, activity levels, walking ability and footwear comfort at all intervals following the orthotic treatment (p?相似文献   
995.
Song SJ  Choi J  Park YD  Lee JJ  Hong SY  Sun K 《Artificial organs》2010,34(11):1044-1048
Bioprinting is an emerging technology for constructing tissue or bioartificial organs with complex three-dimensional (3D) structures. It provides high-precision spatial shape forming ability on a larger scale than conventional tissue engineering methods, and simultaneous multiple components composition ability. Bioprinting utilizes a computer-controlled 3D printer mechanism for 3D biological structure construction. To implement minimal pattern width in a hydrogel-based bioprinting system, a study on printing characteristics was performed by varying printer control parameters. The experimental results showed that printing pattern width depends on associated printer control parameters such as printing flow rate, nozzle diameter, and nozzle velocity. The system under development showed acceptable feasibility of potential use for accurate printing pattern implementation in tissue engineering applications and is another example of novel techniques for regenerative medicine based on computer-aided biofabrication system.  相似文献   
996.
997.
Long-term depression (LTD) is one of the most widely investigated models of the synaptic mechanisms underlying learning and memory. Previous research has shown that induction of LTD in the neocortex decreases measures of pyramidal cell dendritic morphology in both layers III and V. Here, we investigated the effects of LTD induction on 1) the time course of recovery of synaptic efficacy, 2) movement representations, 3) cortical thickness and layer V neuron density, and 4) the density of excitatory and inhibitory synapses in layer V of sensorimotor neocortex. Rats carried a stimulating electrode in the midline corpus callosum and a recording electrode in the right sensorimotor neocortex. Each rat received either low-frequency stimulation composed of 900 pulses at 1 Hz or handling daily for a total of 20-25 days. Callosal-neocortical evoked potentials were recorded in the right hemisphere before and after stimulation or handling. Our results show that LTD induction lasts for 3 weeks and results in smaller motor maps of the caudal forelimb area. We did not observe any reduction in neocortical thickness or neuron density. There was a reduction in the density of excitatory perforated synapses and an increase in the density of inhibitory synapses in layer V of the sensorimotor neocortex, thereby providing a general mechanism for the reduction in motor map size. This study sheds light on the interaction between an artificial model of learning, receptive field characteristics, and synaptic number in the sensorimotor cortex.  相似文献   
998.
BACKGROUND: Arteriovenous (AV) grafts in haemodialysis patients usually fail due to thrombosis or infection. There is limited information on whether graft outcomes in HIV-positive haemodialysis patients differ from those in HIV-negative controls. METHODS: Using a prospective, computerized vascular access database, we identified retrospectively 15 HIV-positive dialysis patients having a graft placed during a 6.5-year period (January 1999 to June 2005), and compared their graft outcomes to those observed in 30 age-, sex- and access date-matched HIV-negative control patients. In addition, the outcomes of AV fistulas in 23 HIV-positive patients were compared with those observed in 32 matched HIV-negative controls. RESULTS: Thrombosis-free graft survival was substantially worse among the HIV-positive patients than in the HIV-negative controls (1-year survival, 17% vs 62%). The hazard ratio for graft thrombosis in the HIV-positive patients was 3.22 (95% CI, 1.66-10.32, P = 0.002). Infection-free graft survival was also lower in HIV-positive patients (hazard ratio 3.51; 95% CI, 1.21-18.85, P = 0.025). Finally, cumulative graft survival (from creation until permanent failure) tended to be lower in HIV-positive patients (1 year survival, 41% vs 65%, P = 0.07). The primary failure rate of fistulas (those never usable for dialysis) was similar in HIV-positive patients and in their controls (44% vs 41%, P = 0.83). Cumulative fistula survival was similar for HIV-positive and negative patients (hazard ratio 1.32; 95% CI, 0.65-3.58, P = 0.33). CONCLUSION: AV grafts have inferior outcomes in HIV-positive patients as compared with HIV-negative patients, whereas fistulas have a similar survival in both groups.  相似文献   
999.
Background: The authors determined whether desflurane altered myocardial excitation-contraction coupling and electrophysiologic behavior in the same manner as isoflurane and sevoflurane.

Methods: The effects of desflurane on isometric force in guinea pig ventricular papillary muscles were studied in modified standard and in 26 mm K+ Tyrode solution with 0.1 [mu]m isoproterenol. Desflurane effects on sarcoplasmic reticulum Ca2+ release were also determined by examining its actions on rat papillary muscles, guinea pig papillary muscles in low-Na+ Tyrode solution, and rapid cooling contractures. Normal and slow action potentials were recorded using a conventional microelectrode technique. Ca2+ and K+ currents of guinea pig ventricular myocytes were examined.

Results: Desflurane (5.3% and 11.6%) decreased peak force to approximately 70% and 40% of the baseline, respectively, similar to the effects of equianesthetic isoflurane concentrations. With isoproterenol in 26 mm K+ Tyrode solution, desflurane markedly depressed late peaking force and modestly depressed early peak force. The rested state contractions of rat myocardium or guinea pig myocardium in low-Na+ Tyrode solution were modestly depressed, whereas rapid cooling contractures were virtually abolished after desflurane administration. Desflurane significantly prolonged the action potential duration. Desflurane reduced L-type Ca2+ current and the delayed outward K+ current but did not alter the inward rectifier K+ current.  相似文献   

1000.
Gumbs AA  Pomp A  Gagner M 《Obesity surgery》2007,17(9):1137-1145
When behavioral or anatomic issues are not present, revisional surgery should be approached with a goal of treating malnutrition or enhancing excess weight loss. Unfortunately, no randomized controlled trials currently exist to help the practicing bariatric surgeon choose which revisional procedure to perform. A review of the available literature was undertaken and compared with our standard practices to see if any guidelines could be devised. At our institution, patients who have failed jejunal-ileal bypass are reversed in the setting of malnutrition and converted to a sleeve gastrectomy (SG) followed by duodenal switch (DS) as a second stage procedure in the setting of inadequate weight loss. After failed vertical banded gastroplasty (VBG), patients are converted to a Roux-en-Y gastric bypass (RYGBP). After failed adjustable gastric band (AGB) placement, we perform RYGBP. In the super-obese, we leave the band in place or convert to a DS with band removal. In patients with failed RYGBP, we convert our patients to DS, but placement of an AGB may be an acceptable option.  相似文献   
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