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991.
Neurological damage, and stroke in particular, is the leading cause of long term disability worldwide. There is growing interest in the part that central nervous system reorganisation plays in recovery of function. Techniques such as functional magnetic resonance imaging and transcranial magnetic stimulation permit the non-invasive study of the working human brain, and suggest that functionally relevant adaptive changes occur in the human brain after focal damage. An understanding of how these changes are related to recovery will facilitate the development of novel therapeutic techniques that are based on neurobiological principles and that are designed to minimise impairment in appropriately targeted patients suffering from stroke.  相似文献   
992.
993.
Trends in the leading causes of death in the United States, 1970-2002   总被引:5,自引:1,他引:4  
Jemal A  Ward E  Hao Y  Thun M 《JAMA》2005,294(10):1255-1259
Context  The decrease in overall death rates in the United States may mask changes in death rates from specific conditions. Objective  To examine temporal trends in the age-standardized death rates and in the number of deaths from the 6 leading causes of death in the United States. Design and Setting  Analyses of vital statistics data on mortality in the United States from 1970 to 2002. Main Outcome Measure  The age-standardized death rate and number of deaths (coded as underlying cause) from each of the 6 leading causes of death: heart disease, stroke, cancer, chronic obstructive pulmonary disease, accidents (ie, related to transportation [motor vehicle, other land vehicles, and water, air, and space] and not related to transportation [falls, fire, and accidental posioning]), and diabetes mellitus. Results  The age-standardized death rate (per 100 000 per year) from all causes combined decreased from 1242 in 1970 to 845 in 2002. The largest percentage decreases were in death rates from stroke (63%), heart disease (52%), and accidents (41%). The largest absolute decreases in death rates were from heart disease (262 deaths per 100 000), stroke (96 deaths per 100 000), and accidents (26 deaths per 100 000).The death rate from all types of cancer combined increased between 1970 and 1990 and then decreased through 2002, yielding a net decline of 2.7%. In contrast, death rates doubled from chronic obstructive pulmonary disease over the entire time interval and increased by 45% for diabetes since 1987. Despite decreases in age-standardized death rates from 4 of the 6 leading causes of death, the absolute number of deaths from these conditions continues to increase, although these deaths occur at older ages. Conclusions  The absolute number of deaths and age at death continue to increase in the United States. These temporal trends have major implications for health care and health care costs in an aging population.   相似文献   
994.
BACKGROUND: Young infants are at risk of vitamin A deficiency. Supplementation of breastfeeding mothers improves the vitamin A status of their infants, but there are no data regarding its effect on infant mortality, and data on the effect of directly supplementing infants during the first few weeks of life are conflicting. OBJECTIVE: The objective was to measure the effect on infant mortality of supplementing neonates and their HIV-negative mothers with single, large doses of vitamin A during the immediate postpartum period. DESIGN: A randomized, placebo-controlled, 2-by-2 factorial design trial was conducted in 14,110 mothers and their infants; 9208 of the mothers were HIV-negative at delivery, remained such during the postpartum year, and were retained in the current analysis. The infants were randomly assigned within 96 h of delivery to 1 of 4 treatment groups: mothers and infants received vitamin A (Aa), mothers received vitamin A and infants received placebo (Ap), mothers received placebo and infants received vitamin A (Pa), and both mothers and infants received placebo (Pp). The vitamin A dose in the mothers was 400,000 IU and in the infants was 50,000 IU. The mother-infant pairs were followed to 12 mo. RESULTS: Hazard ratios (95% CI) for 12 mo mortality among infants in the maternal-supplemented and infant-supplemented groups were 1.17 (0.87, 1.58) and 1.08 (0.80, 1.46), respectively. Hazard ratios (95% CI) for the Aa, Ap, and Pa groups compared with the Pp group were 1.28 (0.83, 1.98), 1.27 (0.82, 1.97), and 1.18 (0.76, 1.83), respectively. These data indicate no overall effect. Serum retinol concentrations among a subsample of women were similar to reference norms. CONCLUSION: Postpartum maternal or neonatal vitamin A supplementation may not reduce infant mortality in infants of HIV-negative women with an apparently adequate vitamin A status.  相似文献   
995.
BACKGROUND: Injury is the leading cause of preventable morbidity and mortality in Canada. The "ice berg" effect in injuries was proposed to address the injury statistics that are often poorly documented. The aim of this investigation was to quantify the severity and magnitude of iceberg effect in Ontario, Canada. METHODS: Data from Vital Statistics (1999, mortality), Canadian Institute for Health Information (2001, hospitalizations), Census (2001, demographic information), National Ambulatory Care Reporting System (2001, emergency department visits), and the Canadian Community Health Survey (2000/01, other injuries) were used to construct the Ontario injury iceberg for ages 12 years and older. RESULTS: There were 79,577 fatalities in Ontario in 1999; 2,645 were attributable to injuries (crude rate: 2.3 per 10,000). Of the 913,540 hospitalizations (2001), 67,301 were caused by injuries. There were 3,520,253 emergency department (ED) visits (2001) and 959,278 were attributable to injuries. For injuries treated elsewhere, the most common treatment site was the physician's office (23.3%). The most common cause of injuries (CCHS) was falls (37.4%) and exertion/movement (20.5%). There were 1,928,000 injuries causing functional impairment (one injury to five individuals in the population). INTERPRETATION The high ratio of injury-related ED visits to deaths illustrated the high volume of injuries that present to the ED. The ratio of injuries resulting in functional impairment to the population demonstrates.that such injuries can be problematic, even if not resulting in hospitalization. Constructing the injury iceberg using valid data should assist researchers and decision-makers in priority setting.  相似文献   
996.
PURPOSE OF REVIEW: Through the prostate-specific antigen era, the proportion of men less than 55 years old with newly diagnosed prostate cancer more than doubled to almost 15%. As increasing numbers of men are living longer with prostate cancer, larger proportions will eventually present to our collective practices with rising prostate-specific antigen levels. Such prostate-specific antigen relapses, conservatively estimated to affect approximately 50 000 men each year, have become the most common form of advanced prostate cancer in the current period. RECENT FINDINGS: Increasing evidence suggests that early hormonal therapy improves progression-free survival and may alter the cancer-specific survival. However, there is a cost to pay in side-effects when androgen deprivation is administered over prolonged periods. The non-steroidal anti-androgen bicalutamide may offer an equivalent progression-free survival to castration without the complications of androgen deprivation. Observational data seem to indicate that high-risk individuals (i.e. those with high-grade, high-stage disease or a prostate-specific antigen doubling time less than 12 months) may also receive benefit from early therapy. SUMMARY: The definition of advanced prostate cancer has changed. Multimodal therapy improves cancer-specific outcomes especially in men with high-risk disease. The potential opportunities for novel therapeutic agents with low associated morbidity are great.  相似文献   
997.
Electronic medical records of a large veterinary practice were used for surveillance of potential space-time clustering of adverse events associated with rabies vaccination in dogs. The study population was 257,564 dogs vaccinated in 169 hospitals in 13 US metropolitan areas during a 24-month period. Using a scan statistic for population rate data, significant space-time clusters were identified involving the Atlanta and Tampa/St. Petersburg areas during a 4-month period. Separate spatial-temporal analyses of these cities using coordinates for individual address coordinates identified one significant patient cluster (P=0.002), associated with a 23.26 km-radius area in Atlanta (20 adverse events in 702 dogs; 2.85%) from November 2002 through February 2003. This percentage of adverse events was significantly increased after adjustment for host-related factors and the number of concurrent vaccinations.  相似文献   
998.
Chabot S  Brewer A  Lowell G  Plante M  Cyr S  Burt DS  Ward BJ 《Vaccine》2005,23(11):1374-1383
Protollin-MV is a vaccine produced by mixing split measles virus (MV) antigen with the novel adjuvant Protollin (Neisseria meningitidis outer membrane proteins non-covalently complexed with Shigella flexneri 2a lipopolysaccharide). Intranasal immunization of mice with two or three doses of Protollin-MV induces both serum IgG and mucosal IgA with strong neutralizing activity. There is a dose-dependent shift towards lower IgG1:IgG2a ratios and MV-specific IFNgamma production in splenocytes. Intranasal Protollin-MV can therefore induce systemic and mucosal neutralizing antibody responses as well as elicit a balanced TH1/TH2-type response.  相似文献   
999.
The demand for insertion of long-term central venous (Hickman type) catheters is thought to be increasing. Organisation is required to meet this demand in a safe and efficient manner. This report reviews the results from a dedicated, anaesthetic led vascular access list over the initial 61-month period. One thousand procedures were performed. Nine hundred and twenty catheters were inserted under local anaesthesia, with or without intravenous sedation and analgesia. Eighty catheters were removed. All procedures were performed during a dedicated once weekly, morning list. A total of 53% of all procedures were performed on a day-case basis, 43% on in-patients. Only 1.5% of patients required an unexpected overnight stay (usually medically unfit patients). There were 81 (9%) cancellations on the day of procedure due to neutropaenia, pneumonia or urinary tract infections. Ultrasound guidance was used initially selectively in 14%, latterly in 100% of procedures and fluoroscopy in all insertions to confirm or adjust catheter position. This service has been well received by patients and oncology services. In addition it provides an interesting area of practice for anaesthetists and an ideal environment for teaching more advanced aspects of central venous access. It may provide a template of service for other centres.  相似文献   
1000.
A closed loop system of diabetes control would minimize hyperglycemia and hypoglycemia. We therefore implanted and tested a subcutaneous amperometric glucose sensor array in alloxan-diabetic rats. Each array employed four sensing units, the outputs of which were processed in real time to yield a unified signal. We utilized a gain-scheduled insulin control algorithm which rapidly reduced insulin delivery as glucose concentration declined. Such a system was generally effective in controlling glycemia and the degree of lag between blood glucose and the sensor signal was usually 3-8 min. After prolonged implantation, this lag was sometimes longer, which led to impairment of sensor accuracy. Using a prospective two-point calibration method, sensor accuracy and closed loop control were good. A revised algorithm yielded better glycemic control than the initial algorithm did. Future research needs to further improve calibration methods and reduce foreign body fibrosis in order to avoid a time-related increase in lag duration.  相似文献   
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