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991.
Cancer statistics, 2005   总被引:157,自引:0,他引:157  
Each year, the American Cancer Society estimates the number of new cancer cases and deaths expected in the United States in the current year and compiles the most recent data on cancer incidence, mortality, and survival based on incidence data from the National Cancer Institute and mortality data from the National Center for Health Statistics. Incidence and death rates are age-standardized to the 2000 US standard million population. A total of 1,372,910 new cancer cases and 570,280 deaths are expected in the United States in 2005. When deaths are aggregated by age, cancer has surpassed heart disease as the leading cause of death for persons younger than 85 since 1999. When adjusted to delayed reporting, cancer incidence rates stabilized in men from 1995 through 2001 but continued to increase by 0.3% per year from 1987 through 2001 in women. The death rate from all cancers combined has decreased by 1.5% per year since 1993 among men and by 0.8% per year since 1992 among women. The mortality rate has also continued to decrease from the three most common cancer sites in men (lung and bronchus, colon and rectum, and prostate) and from breast and colorectal cancers in women. Lung cancer mortality among women has leveled off after increasing for many decades. In analyses by race and ethnicity, African American men and women have 40% and 20% higher death rates from all cancers combined than White men and women, respectively. Cancer incidence and death rates are lower in other racial and ethnic groups than in Whites and African Americans for all sites combined and for the four major cancer sites. However, these groups generally have higher rates for stomach, liver, and cervical cancers than Whites. Furthermore, minority populations are more likely to be diagnosed with advanced stage disease than are Whites. Progress in reducing the burden of suffering and death from cancer can be accelerated by applying existing cancer control knowledge across all segments of the population.  相似文献   
992.
993.
Murray DJ  Boulet JR  Kras JF  McAllister JD  Cox TE 《Anesthesia and analgesia》2005,101(4):1127-34, table of contents
In an earlier study, trained raters provided reliable scores for a simulation-based anesthesia acute care skill assessment. In this study, we used this acute care skill evaluation to measure the performance of student nurse anesthetists and resident physician trainees. The performance of these trainees was analyzed to provide data about acute care skill acquisition during training. Group comparisons provided information about the validity of the simulated exercises. A set of six simulation-based acute care exercises was used to evaluate 43 anesthesia trainees (28 residents [12 junior and 16 senior] and 15 student nurse anesthetists). Six raters scored the participants on each exercise using either a detailed checklist, key-action items, or a global rating. Trainees with the most education and clinical experience (i.e., senior residents) received higher scores on the simulation scenarios, providing some evidence to support the validity of the multi-scenario assessment. Trainees varied markedly in ability depending on the content of the exercise. In general, anesthesia providers demonstrated similar aptitude in managing each of the six simulated events. Most participants effectively managed ventricular tachycardia, but postoperative events such as anaphylaxis and stroke were more difficult for all trainees to promptly recognize and treat. Training programs could use a simulation-based multiple encounter evaluation to measure provider skill in acute care. IMPLICATIONS: A trainee's skill in managing critical events can be assessed using a multiple scenario simulation-based performance evaluation.  相似文献   
994.
995.
Health systems can primarily improve the health of individuals and populations by delivering high-quality interventions to those who may benefit from them. We propose a concept of effective coverage as the probability that individuals will receive health gain from an intervention if they need it. Understanding the extent to which health systems are delivering key interventions to those who will benefit from them and the factors that explain gaps in delivery are a critical input to decision-making at the local, national and global levels. We develop an integrated conceptual framework for monitoring and analyzing the delivery of high-quality interventions to those who need them. This framework can help clarify the inter-relationships between notions of access, demand for care, utilization, and coverage on the one hand and highlight the requirements for health information systems that can sustain this type of analysis. We discuss measurement strategies and demonstrate the concept by means of a simple simulation model.  相似文献   
996.
This study compares a standard soft dressing (SSD) with a removable rigid dressing (RRD) in a randomized, controlled trial using 50 dysvascular trans-tibial amputees. Both dressing types were applied immediately post-operatively and were only removed for wound dressing changes. Half the subjects were allocated prospectively by ballot to either the RRD group or the SSD group. There was a strong trend indicating that primary wound healing of the stump occurred almost 2 weeks earlier in subjects using the RRD (RRD = 51.2 days +/- 19.4; SSD = 64.7 days +/- 29.5; P= 0.07; RRD: n =17; SSD: n = 14.) There were no significant differences between the other parameters measured which included time to prosthetic fitting, length of hospital stay, incidence of stump breakdown, and time taken for stump volume to stabilize. The incidence of stump damage due to falls was also recorded, the results indicating that RRDs may protect the new stump from trauma.  相似文献   
997.
998.
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   
999.
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   
1000.
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   
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