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991.
992.
Multisensory interactions are observed in species from single-cell organisms to humans. Important early work was primarily carried out in the cat superior colliculus and a set of critical parameters for their occurrence were defined. Primary among these were temporal synchrony and spatial alignment of bisensory inputs. Here, we assessed whether spatial alignment was also a critical parameter for the temporally earliest multisensory interactions that are observed in lower-level sensory cortices of the human. While multisensory interactions in humans have been shown behaviorally for spatially disparate stimuli (e.g. the ventriloquist effect), it is not clear if such effects are due to early sensory level integration or later perceptual level processing. In the present study, we used psychophysical and electrophysiological indices to show that auditory-somatosensory interactions in humans occur via the same early sensory mechanism both when stimuli are in and out of spatial register. Subjects more rapidly detected multisensory than unisensory events. At just 50 ms post-stimulus, neural responses to the multisensory 'whole' were greater than the summed responses from the constituent unisensory 'parts'. For all spatial configurations, this effect followed from a modulation of the strength of brain responses, rather than the activation of regions specifically responsive to multisensory pairs. Using the local auto-regressive average source estimation, we localized the initial auditory-somatosensory interactions to auditory association areas contralateral to the side of somatosensory stimulation. Thus, multisensory interactions can occur across wide peripersonal spatial separations remarkably early in sensory processing and in cortical regions traditionally considered unisensory.  相似文献   
993.
Background Factors prognostic for survival in patients with locally recurrent extremity soft tissue sarcomas (STS) are poorly defined, thus making it difficult to identify high-risk patients who may benefit from adjuvant therapy.Methods A total of 1421 patients underwent surgical treatment for primary extremity STS at a single institution between 1982 and 2002. Of these, 179 (13%) patients underwent complete surgical resection of an isolated local recurrence and were the subjects of this study. Clinicopathologic factors from both the primary tumor and the local recurrence were analyzed.Results The median interval to initial local recurrence was 16 months: 65% developed a local recurrence by 2 years and 90% by 4 years. Only four patients who presented with a low-grade primary tumor progressed to a high-grade local recurrence. Independent prognostic factors for disease-specific survival after local recurrence were a high histological grade (hazard ratio, 5.1; P = .0004), a large local recurrence tumor size (hazard ratio, 1.5; P = .0001), and a short local recurrence–free interval (hazard ratio, 1.6; P = .0001). Patients who developed a local recurrence >5 cm in 16 months (n = 44; 0 low grade) had a 4-year disease-specific survival of 18%, compared with 81% for patients who developed a local recurrence 5 cm in >16 months (n = 46; 11 low grade).Conclusions Histological grade, local recurrence size, and local recurrence–free interval are independently predictive of survival in patients with locally recurrent extremity STS. A large local recurrence that develops in a short interval indicates a biologically aggressive tumor with a high tumor-specific mortality. Patients who develop such recurrences are ideal subjects for systemic neoadjuvant therapy trials.  相似文献   
994.
BACKGROUND: It is not clear if more intense surveillance is associated with improved survival after curative resection for cancer. In the context of a followup program after curative gastrectomy, recurrence and survival were investigated for patients presenting with either symptomatic or asymptomatic recurrence. STUDY DESIGN: A prospectively maintained gastric cancer database was used to identify all patients who underwent a curative (R0) gastrectomy from July 1985 to June 2000. Survival curves were generated for patients with either symptomatic or asymptomatic recurrence, and the prognostic variables associated with outcomes were identified. RESULTS: Of 1,172 patients who underwent a curative (R0) gastrectomy, 561 patients (48%) had documented recurrence and 382 patients had complete data about symptoms. Median time to recurrence was 10.8months for asymptomatic patients and 12.4months for symptomatic patients (p = NS). Median postrecurrence survival was 13.5months for asymptomatic patients and 4.8months for symptomatic patients (p < 0.01). Median disease-specific survival was 29.4months for asymptomatic patients and 21.6months for symptomatic patients (p < 0.05). Variables predictive of poor postrecurrence survival included symptomatic recurrence, advanced stage (III/IV), poor differentiation, short disease-free interval (<12months), and multiple sites of recurrence. CONCLUSIONS: Followup did not identify asymptomatic recurrence earlier than symptomatic recurrence. Patients with symptomatic recurrence have more aggressive disease with a shorter postrecurrence survival. The impact of detecting asymptomatic recurrence in the course of followup after curative gastrectomy could not be distinguished from the effects of four powerful biologic variables that also interact to govern outcomes.  相似文献   
995.
Radio-ulnar dissociation can result from high-injury trauma that the compressive forces traverse the wrist forearm and elbow. This injury can be thought of as an "unhappy triad" of radial head fracture, triangular fibrocartilage complex failure, and a tear of the interosseous membrane. The radius is the primary stabilizer of the forearm with the forearm interosseous membrane enabling load sharing between the radius and the ulna. The central one-third of the interosseous membrane is 3 times stronger than the membranous portion and approaches the strength of the anterior cruciate ligament for determining interosseous membrane injury. Imaging studies with proven diagnostic efficacy include magnetic resonance imaging and ultrasound. Surgical treatment should be considered when circumstances imply longitudinal instability of the forearm. Surgical treatment includes open reduction/internal fixation or prosthetic replacement of the radial head as well as repair of the disrupted triangular fibrocartilage complex. Successful treatment of radioulnar dissociation is predicated on early diagnosis of the condition.  相似文献   
996.
OBJECTIVE: We reviewed the presentation, management, and late events in a recent experience with aortic graft-enteric communications (secondary aortoenteric fistula) to identify variables associated with poor outcomes. METHODS: Since 1991, 29 patients (19 men, 10 women; mean age, 70) presented with a secondary aortoenteric fistula. The duration from aortic graft implantation to aortoenteric fistula development ranged from 8 months to 180 months (mean, 47 months). Presenting symptoms included gastrointestinal bleeding (n = 25), sepsis and retroperitoneal abscess (n = 3), and ruptured para-anastomotic aneurysm (n = 1). One third (10/29) of patients were hypotensive at presentation. Repair was accomplished by graft excision with axillobifemoral bypass (17 simultaneous, 8 staged), graft excision with in situ deep vein replacement (n = 2), or graft excision with rifampin-treated prosthetic replacement (n = 2). Mean follow-up was 51 months, and the incidence of late events was reported by life table methods. RESULTS: The operative (< or = 30-day) mortality rate was 21%, with shock at presentation (P < .01), the need for preoperative transfusion (P < .01), and use of suprarenal aortic clamping during aortoenteric fistula repair (P = .03) associated with lethal outcome. Cumulative mortality related to aortoenteric fistula management was only 24% within an overall 5-year survival rate of 61%. Freedom from recurrent infection or amputation was 86% and 88% at 5 years, respectively, and assisted graft patency was 79%. Presence of staphylococcal species in 22% of patients and occasional operative findings of adjacent perigraft "biofilm" suggests that underlying indolent graft infection may contribute to the development of aortoenteric fistula in some cases. CONCLUSION: Outcomes associated with aortoenteric fistula repair were surprisingly favorable in the absence of preoperative hemodynamic instability.  相似文献   
997.
Forty years ago, Marshall Urist described a partially purified extract of demineralized bone matrix which induced the formation of ectopic bone. This substance, bone morphogenetic protein/non-collagenous protein (BMP/NCP), was never purified to homogeneity but other investigators used similar starting materials to clone a number of recombinant BMPs. Urist recognized that his material probably contained the BMPs which had been cloned by others but always contended that it contained another, more potent, bone inducing material which differed significantly in its physical and chemical properties from the known BMPs. We have used Urist's protocol to isolate a protein that has the chemical and physical properties of Urist's "BMP". It is an 18.5 kD fragment of the bone matrix protein, SPP-24. This fragment contains the cystatin-like domain of SPP-24. We have located a 19 amino acid region which is similar to the TGF-beta/BMP-binding region of fetuin, a member of the cystatin family of protease inhibitors. A cyclic peptide, which we call BMP binding peptide (BBP) was generated using this sequence. The peptide avidly bound rhBMP-2 with a KD of 3 x 10(-5) M. When implanted alone in mouse muscle, the peptide frequently induced dystrophic calcification. When implanted with rhBMP-2, the peptide enhanced the osteogenic activity of the recombinant molecule. We hypothesize that Urist's "BMP" was a fragment of SPP-24 which influenced bone induction by binding to bone morphogenetic proteins. BBP may be clinically useful because of its effects on other bone-inducing substances.  相似文献   
998.
999.
OBJECTIVE: To determine the relative prevalence of various definitions of microscopic haematuria (MH) in patients with renal neoplasms and controls, and to predict the likely outcome of renal imaging for those definitions. PATIENTS AND METHODS: In a retrospective case-control study 278 adult men and woman seen between 1998 and 2003 with untreated renal neoplasms were compared to controls matched for age and sex. All cases and controls had renal imaging within 6 months of a urine analysis. Patients were excluded for gross haematuria or other conditions associated with MH but not relevant to upper tract imaging. Adjusted odds ratios (OR) computed for 13 definitions of MH by conditional logistic regression were the primary outcome measures. Additional outcome measures were ORs in selected subsets. Hypothetical performance characteristics of a positive urine analysis were then derived to predict the likely results of detecting renal neoplasms for each definition of MH. RESULTS: The OR (95% confidence interval) for the entire series of cases and controls, both symptomatic and asymptomatic, was 2.0 (1.02-3.92, P = 0.04) for MH defined as > or = 4 red blood cells per high-power field (RBC/HPF) and 2.2 (1.09-4.52, P = 0.03) for > or = 5 RBC/HPF. No significant OR was calculated for < or = 3 RBC/HPF, nor for a subgroup of patients with MH in a routine urine analysis obtained during a periodic health examination. Symptomatic patients had an OR of 13.68 (1.6-117.1, P = 0.02) for MH defined as > or = 5 RBC/HPF. The sensitivity of a positive test decreased from 24.8% to 5.04% as the definition for MH became more stringent. The theoretical positive predictive value (assuming a prevalence of renal cell neoplasms of 0.25%) of the most stringent definition of MH was 0.58%. CONCLUSIONS: Patients with renal neoplasms have about twice the prevalence of MH with > or = 4 or 5 RBC/HPF in a single urine sample compared with matched controls, but this difference has little impact on the hypothetical detection rate of renal cancer. Imaging the kidney for low-grade MH in a routine urine analysis discovered at a periodic health examination in an otherwise asymptomatic patient is tantamount to screening without cause, and can be deferred for selected patients. The clinical context is as important as the degree of MH when deciding to image the kidneys.  相似文献   
1000.
This study examined the temporal anthropometric changes in idealized female body images in the media (i.e., Playboy magazine Playmates of the Year, Miss America Pageant winners, and fashion models) and young women in general across eight decades. Overall, all anthropometric measures differed significantly over time. BMI for all women in the idealized groups tended to decline significantly over time, while the BMI for YoungWomen increased significantly. Models tended to have the smallest bust and hips, Playmates the largest bust, and young women in general the largest waist and hips. The general trend for all groups was to move from a less curvaceous body shape in the early part of the twentieth century to a more curvaceous shape at mid-century and returning to a less curvaceous shape at the end of the century. Idealized women have a body size unlike that of Young Women and the chasm between the media- defined ideal and reality is continuing to diverge.  相似文献   
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