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101.
BACKGROUND: Analysis of the mechanism and severity of injury over time may permit a more focused planning of acute care and trauma prevention programs. METHODS: A retrospective, population-based study examining severe traumatic injury in a single county was undertaken. Three overlapping data sets were used to form a composite injury data set. RESULTS: There were 55,664 patients included in the study. A total of 40,897 (73.5%) patients survived and 14,767 (26.5%) died. Of those patients who died, 8,910 (60.3%) died in the field and were not transported to a trauma center. There was an increase in the mean age of all trauma victims (3 years) and an increase of 5 years in fatally injured patients. The mean Injury Severity Score decreased from 14.7 to 11.6 (p < 0.01); however, Injury Severity Score for fatal patients remained constant (39.7). The overall injury rate remained unchanged (195 per 10(5)), whereas the fatal injury rate decreased by 22% (45.9 per 10(5)) over the 11-year study period. The leading cause of injury was motor vehicle crash, followed by assault. The leading cause of fatal injury was suicide, followed by homicide. CONCLUSION: A combination of three independent injury data sources generated a composite data set of serious and fatal injury. This regional injury analysis was the most comprehensive overview of injury in our region. Important observations included the following: there has been no change in the overall incidence of severe injury within our county; the incidence of fatal traumatic injury has significantly decreased; the leading causes of nonfatal injury do not correlate with the rank order of fatal injury; intentional injury was the leading cause of injury deaths; and scene fatalities represent a poorly studied group of patients who may benefit from primary prevention and injury control research.  相似文献   
102.
Intramedullary spinal cord metastases (ISCMs) are very rare, but can cause devastating complications from underlying breast cancer. We report the case of a woman with known metastatic breast cancer and progressive neurologic deterioration caused by an ISCM. The epidemiology, pathogenesis, clinical presentation, diagnostic considerations, and therapeutic options are discussed.  相似文献   
103.
With increasing age, the ability to produce protective antibodies in response to immunization declines, leading to a reduced efficacy of vaccination in the elderly. To examine the effect of age on the cognate function of CD4 T cells, we have used a novel adoptive transfer model that allows us to compare identical numbers of antigen-specific naive T cells from young and aged TCR transgenic (Tg) donors. Upon transfer of aged donor CD4 T cells to young hosts, there was significantly reduced expansion and germinal center (GC) differentiation of the antigen-specific B cell population after immunization. This reduced cognate helper function was seen at all time points and over a wide range of donor cell numbers. In hosts receiving aged CD4 cells, there were also dramatically lower levels of antigen-specific IgG. These age-related defects were not due to defects in migration of the aged CD4 T cells, but may be attributable to reduced CD154 (CD40L) expression. Furthermore, we found that there was no difference in B cell expansion and differentiation or in IgG production when young CD4 T cells were transferred to young or aged hosts. Our results show that, in this model, age-related reductions in the cognate helper function of CD4 T cells contribute significantly to defects in humoral responses observed in aged individuals.  相似文献   
104.
In this randomized, 2-way crossover study, the potential for interaction was investigated between atorvastatin and ximelagatran, an oral direct thrombin inhibitor. Healthy female and male volunteers (n = 16) received atorvastatin 40 mg as a single oral dose and, in a separate study period, ximelagatran 36 mg twice daily for 5 days plus a 40-mg oral dose of atorvastatin on the morning of day 4. In the 15 subjects completing the study, no pharmacokinetic interaction was detected between atorvastatin and ximelagatran for all parameters investigated, including melagatran (the active form of ximelagatran) area under the plasma concentration versus time curve (AUC) and maximum plasma concentration, atorvastatin acid AUC, and AUC of active 3-hydroxy-3-methyl-glutaryl-coenzyme-A (HMG-CoA) reductase inhibitors. Atorvastatin did not alter the melagatran-induced prolongation of the activated partial thromboplastin time, and both drugs were well tolerated when administered in combination. In conclusion, no pharmacokinetic or pharmacodynamic interaction between atorvastatin and ximelagatran was observed in this study.  相似文献   
105.
The oral direct thrombin inhibitor ximelagatran is being developed for the prevention and treatment of thromboembolism. This single-blind, randomized, placebo-controlled, parallel-group study investigated the potential for the interaction of ximelagatran (36 mg every 12 hours for 8 days, measured as its active form melagatran in blood) and amiodarone (single 600-mg oral dose on day 4) in healthy male subjects (n = 26). For amiodarone + ximelagatran versus amiodarone + placebo, geometric mean ratios (90% confidence intervals for amiodarone AUC(0-120) and C(max) were 0.87 (0.69-1.08) and 0.86 (0.66-1.11), respectively. For desethylamiodarone, the principal metabolite of amiodarone, the corresponding ratios were 1.00 (0.89-1.12) for AUC(0-120) and 0.92 (0.77-1.09) for C(max).The geometric mean ratios (90% confidence intervals) for ximelagatran + amiodarone versus ximelagatran were 1.21 (1.17-1.25) for melagatran AUC(0-12) and 1.23 (1.18-1.28) for melagatran C(max). These confidence intervals were within or only slightly outside the interval, suggesting no interaction (0.8-1.25 for the effect of amiodarone on melagatran and 0.7-1.43 for the effect of melagatran on amiodarone or desethylamiodarone). Amiodarone did not affect the concentration-effect relationship of melagatran on activated partial thromboplastin time. Ximelagatran was well tolerated when coadministered with a single dose of amiodarone. Evaluation of the safety of the combination is needed to confirm that the relatively small pharmacokinetic changes in this study are of no clinical significance.  相似文献   
106.
PURPOSE: To determine the response rate (RR) and survival produced by carboplatin + gemcitabine therapy in patients with untreated extensive small cell lung cancer (ESCLC). PATIENTS AND METHODS: Treatment consisted of carboplatin (AUC = 5) on day 1 and gemcitabine (1100 mg/m(2)) on days 1 and 8 of each 21-day cycle for 4 planned cycles (additional cycles allowed as per treating physician). ECOG performance status 0/1/2 was 29, 58, and 13%. Median age was 66.5 years (range: 41.3-83.1), 94% were white, and 50.7% were female. RESULTS: Between August 2000 and February 2002, 69 patients with ESCLC were enrolled. All 69 patients were included in the safety analysis, and 66 patients were evaluable for response. There were 2 CR (3.0%), 26 PR (39.5%), 23 SD (34.8%), and 15 PD (22.7%) resulting in a RR of 42.5%. The median survival was 9.2 months (range: <1-22.6), and the estimated 1-year survival was 33%. The median TTP was 3.9 months (range: <1-12.8), and the estimated 6-month progression free survival was 24%. The median duration of response was 3.8 months (range: 1.0-9.9). Out of 69 patients, 29, 3, and 16 received 4, 5, and 6 cycles of therapy, respectively. The major Grade 3, 4 toxicities included neutropenia (39.1%), thrombocytopenia (31.9%), anemia (13.0%), and fatigue (4.3%). CONCLUSION: This regimen resulted in survival data that was similar to other regimens for ESCLC and treatment appeared to be well tolerated. Gemcitabine in combination with carboplatin or other active drugs in ESCLC may be worth further investigation.  相似文献   
107.
Retrosplenial cortex (RS) is situated both anatomically and functionally between neocortical and limbic structures involved in spatial navigation. Initial anatomical, electrophysiological and behavioural evidence in both humans and rodents strongly suggested a role for RS in spatial navigation as well. Later studies using more selective cytotoxic lesions in rodents, however, cast doubt on earlier RS studies by failing to find spatial deficits following RS lesions. Contrasting reports from behavioural results on spatial tasks following RS damage have continued to be reported during the past decade. That RS does indeed contribute spatial behaviour even in rodents has been recently reaffirmed. The ambiguity surrounding RS is shown to result from differences in the choice of spatial tasks and rat strains between studies that find RS deficits and those that do not. The reconciliation of behavioural results following RS lesions strengthens the view that RS forms a part of the neural circuitry that underlies spatial navigation.  相似文献   
108.
The relationship between motor maps and cytoarchitectonic subdivisions in rat frontal cortex is not well understood. We use cytoarchitectonic analysis of microstimulation sites and intracellular stimulation of identified cells to develop a cell-based partitioning scheme of rat vibrissa motor cortex and adjacent areas. The results suggest that rat primary motor cortex (M1) is composed of three cytoarchitectonic areas, the agranular medial field (AGm), the agranular lateral field (AG1), and the cingulate area 1 (Cg1), each of which represents movements of different body parts. Vibrissa motor cortex corresponds entirely and for the most part exclusively to AGm. In area AG1 body/head movements can be evoked. In posterior area Cg1 periocular/eye movements and in anterior area Cg1 nose movements can be evoked. In all of these areas stimulation thresholds are very low, and together they form a complete representation of the rat's body surface. A strong myelinization and an expanded layer 5 characterize area AGm. We suggest that both the strong myelinization and the expanded layer 5 of area AGm may represent cytoarchitectonic specializations related to control of high-speed whisking behavior.  相似文献   
109.
Visser TA  Boden C  Giaschi DE 《Vision research》2004,44(21):2521-2535
The attentional blink (AB) refers to a decrease in accuracy that occurs when observers are required to identify, detect or classify the second of two rapidly-sequential targets. The AB is typically attributed to an inability to rapidly reallocate attentional resources from the first to the second target. Thus, it provides an ideal tool to investigate how visual attention is rapidly allocated to sequences of stimuli such as occurs when reading. In the present work, we compared the magnitude of the AB in children with developmental dyslexia to reading-matched and age-matched control groups. In Experiment 1, when two targets were presented in the same spatial location, the AB deficit was similar in the reading-matched and dyslexic groups, but greater in the dyslexic group than in age-matched controls. In Experiment 2, when targets were presented in different spatial locations, performance in the dyslexic group was worse than the age-matched controls and marginally worse than the reading-matched controls. Taken together, the results argue for developmental delays in the ability of children with dyslexia to allocate attention to rapidly-sequential stimuli, as well as some evidence for difficulties that are unique to this group.  相似文献   
110.
PURPOSE: This report aims to increase awareness of an unusual mechanism of orbital injury sustained by bicycle riders. METHODS: In this retrospective small case series, we describe two cases of orbital injury caused by upper eyelid penetration. A 5-year-old boy (patient 1) and a 6-year-old boy (patient 2) presented to our service within a 2-week period. Both had been injured by similarly styled, handlebar-mounted bicycle hand brake levers. Patient 1 had an orbital roof fracture and penetrating brain injury and underwent repair of a left upper eyelid laceration, craniotomy for pseudoencephalocele, and ptosis repair. Patient 2 had orbital hemorrhage and underwent repair of left upper eyelid laceration. RESULTS: In both cases, a handlebar-mounted bicycle hand brake lever perforated the left eyelid when the rider fell onto it. Neither patient was wearing protective headwear or eyewear. Two months after surgery, patient 1 had 20/25 visual acuity OU and excellent cosmetic appearance. Patient 2 had baseline amblyopic vision 2 days after surgery but moved from town and was lost to follow-up. CONCLUSIONS: Orbit injuries from bicycle brake levers are rare, and helmets or protective eyewear probably would not have prevented these injuries. However, a change in the design and/or mounting location of handlebar-mounted brake levers might help prevent further injuries of this type.  相似文献   
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