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991.
OBJECTIVE: AJCC stage at diagnosis determines the treatment approach and indirectly predicts outcome in patients with colorectal carcinoma. The purpose of our study was to investigate whether there was a delay in diagnosis leading to a more advanced stage at diagnosis (which affects outcome) of patients with colorectal cancers because of distance from a referral center, after positive fecal occult blood testing (FOBT). DESIGN: Our retrospective observational study involved all cases of colonic and rectosigmoid cancers that were referred for an endoscopic procedure after an initial positive FOBT done as a part of routine screening in asymptomatic patients. PARTICIPANTS: Roger Maris Cancer Center and University of North Dakota School of Medicine and Health Sciences. RESULTS: Between the years 1996-2001, 178 subjects with biopsy-proven colon cancer and 80 patients with rectosigmoid cancer were included in our study. Pearson's correlation coefficients were constructed to look at the relationship between distance from a referral center (place where the diagnosis was made) and stage at diagnosis in patients with colonic and rectosigmoid malignancies. For the colon cancer group, the regression coefficient between AJCC stage at diagnosis and distance from the referral center was 0.013 and for rectosigmoid cancers it was 0.12. Even after stratifying distances into tertiles, the correlation coefficients did not show a significant relationship (0.04 for colon and 0.16 for rectosigmoid cancers). CONCLUSION: Distance (of residence) from a tertiary care center does not seem to be a barrier to early diagnosis of colorectal carcinoma and primary care providers in rural settings are referring patients appropriately leading to optimal outcomes.  相似文献   
992.
The frequency and types of congenital heart disease in offspring from pregnancies in women with hyperphenylalaninemia were examined in the international prospective Maternal Phenylketonuria Collaborative Study. Relationships of congenital heart disease in offspring to the basal blood phenylalanine level in the mother, metabolic control through diet during pregnancy, and phenylalanine hydroxylase mutations in mother and offspring were determined. The 416 offspring from 412 maternal phenylketonuria pregnancies that produced live births and 100 offspring from the 99 control pregnancies were included in this examination. Thirty-four of the 235 offspring (14%; 95% CI, 10.2 to 19.6%) from pregnancies in phenylketonuric women with a basal phenylalanine level > or = 900 microM (15 mg/dL) [normal blood phenylalanine < 120 microM (2 mg/dL)] and not in metabolic control [phenylalanine level < or = 600 microM (10 mg/dL)] by the eighth gestational week had congenital heart disease compared with one control offspring (1%) with congenital heart disease. One offspring among the 50 (2%) from mothers with non-phenylketonuria mild hyperphenylalaninemia also had congenital heart disease. Coarctation of the aorta and hypoplastic left heart syndrome were overrepresented compared with expected percentages among those with congenital heart disease in the general population. A basal maternal phenylalanine level > 1800 microM (30 mg/dL) significantly increased the risk for bearing a child with congenital heart disease (p = 0.003). Phenylalanine hydroxylase mutations in the mothers and offspring did not have an independent relationship to congenital heart disease but were related through the basal maternal phenylalanine levels. The data in this study indicate that a basal maternal phenylalanine level of 900 microM may be a threshold for congenital heart disease, that women with the most severe degree of phenylketonuria are at highest risk for bearing such a child, and that prevention of the congenital heart disease requires initiation of the low phenylalanine diet before conception or early in pregnancy with metabolic control no later than the eighth gestational week.  相似文献   
993.
The timing and method of treatment of deep palm and finger burns varies widely. Our protocol involves performing full-thickness skin grafts (FTSG) in nonhealing palm burns. We reviewed the functional and cosmetic results after FTSG to the palm. From August 1997 to April 1999, 11 patients (12 palms) underwent excision and FTSG within 2 weeks of injury. A panel of medical and nonmedical professionals evaluated follow-up pictures of the grafts at 1, 2 to 4, and beyond 4 months. Parameters used for evaluation were color match with the unburned skin (1 = no difference to 4 = large difference), graft thickness (1 = flat to 4 = markedly raised), overall appearance (1 = poor to 100 = excellent), and time to maturity. Hand function, as assessed by occupational therapy notes, was also recorded. All 12 grafted palms had a 100% take and healed with minimal scarring. Mean color match scores were 2.4 at 1 month, 1.8 at 2 to 4 months, and 1.6 beyond 4 months. On the graft thickness scale, grafts were given scores of 2.6, 2.2, and 1.9 during the same intervals. The overall appearance was 71 at 1 month, 81 at 2 to 4 months, and 85 beyond 4 months. All grafts except 1 were judged to be mature at 2 to 4 months follow-up. Full passive range of motion was attained in all grafted hands within the period of 2 to 4 months after operation. Early excision and FTSG of deep pediatric palm burns can be performed in the outpatient setting. The grafts have an acceptable color match, are minimally raised, and achieve excellent cosmetic result. The grafts mature within a few months after surgery to allow for rapid return to normal range of motion. FTSG should be considered as a first choice for deep palm burns.  相似文献   
994.
995.
ML, a 70-year-old right-handed woman, presented with a history of semantic memory difficulties and a profound anomia affecting both proper nouns and common nouns following a left-hemisphere CVA some years earlier. She was found to show a striking contrast between her ability to make fine-grained semantic distinctions between objects and animals, on the one hand, and famous faces and names, on the other. Although she was impaired on a series of picture and word semantic comprehension tests when the stimuli consisted of exemplars of object and animal categories, her performance was intact when the materials comprised famous faces and names, suggesting a dissociation between the representation of person-specific knowledge and other categories of semantic information. A number of cases have been reported in which person-specific knowledge has been selectively impaired, but we would suggest that our case provides the clearest evidence so far of the reverse dissociation, in which person-specific knowledge is selectively preserved. We speculate on possible differences in the ways in which person-specific knowledge may be represented, relative to information about objects and animals.  相似文献   
996.
Currently, there are more than 50 million smokers in this country, and approximately 800 billion cigarettes are smoked each year. Smoking is now the leading avoidable cause of morbidity and mortality in the United States. According to one report, over 500,000 deaths per year in the United States alone can be attributed to smoking. For years, orthopaedic surgeons have known about the relationships that putatively exist between smoking and an array of orthopaedic conditions and complications. It has been shown to adversely affect bone mineral density, lumbar disk disease, the rate of hip fractures, and the dynamics of bone and wound healing. Although scientific and clinical information on smoking and its consequences suggests differing degrees of correlation between smoking and orthopaedic conditions, most available data do suggest a real and reproducible relationship. In the past, there have been many individual reports that deal with these relationships separately but very few published comprehensive reviews. This summary of the current literature regarding the relationship between smoking and musculoskeletal diseases and their treatment provides information that can be used clinically by both the practitioner and the patient.  相似文献   
997.
It has previously been reported that unfamiliar face recognition memory is impaired in Parkinson's disease (PD) [(Dewick, H. C., Hanley, J. R., Davies, A. D. M., Playfer, J. R. & Turnbull, C. J., Perception and memory for faces in Parkinson's disease. Neuropsychologia, 1991, 29, 785-802), (Haeske-Dewick, H. C., Are perception and memory for faces influenced by a specific age at onset factor in Parkinson's disease? Neuropsychologia, 1996, 34, 315-320), (Levin, B. E., Llabre, M. M. & Weiner, W. J., Cognitive impairments associated with early Parkinson's disease. Neurology, 1989, 39, 557-561)]. In the work reported here, we consider the possible mechanisms that might underlie this impairment. 28 PD patients and 28 controls were given a two-part test of recognition memory for words and faces, and two perceptual tests to measure their configural and componential processing ability. We found that PD patients were significantly worse than controls on the recognition memory test for faces, but not when the stimuli were words. In addition, PD patients were significantly impaired relative to controls on the closure test (FCT) used to measure configural processing, but there was no difference between the two groups on a test of componential processing ability. Multiple regression analyses revealed that even after accounting for the influence of age, intelligence and level of depression, configural processing ability was the important predictor of unfamiliar face recognition memory in Parkinson's disease. There was no effect of Parkinson's disease specific variables on either face recognition or FCT performance. In addition, some recently diagnosed patients were poor at face recognition. It is suggested that face configuration skills may be affected very early in the course of Parkinson's disease, and that this may be connected to the fact that considerable nigrostriatal degeneration and alteration in brain neurotransmitter levels occur before the clinical symptoms of PD appear.  相似文献   
998.
 【目的】探讨恶性实体瘤患者外周血来源的细胞因子诱导的杀伤细胞的增殖能力、免疫表型及杀瘤活性。【方法】用rhlFN-1,rhlL-2,Anti-CD3mAb与恶性实体瘤患者外周血单个核细胞共孵育。分别在培养第4、7、10、13天进行细胞计数,通过流式细胞术检测细胞免疫表型及MTT法检测对K562细胞的杀伤活性。【结果】恶性实体瘤患者外周血单个核细胞与rhIFN-γ,rhIL-2,Anti-CD3mAb孵育4、7、10、13d,细胞数分别增加(2.5±1.6)、(11.9±3.5)、(22.3±7.8)和(29.5±6.1)倍。CD3^+、CD4^+,CD8^+和CD3^+CD16^+CD56^+细胞在培养第13天分别从(62.8±7.6)%、(31.5±5.8)%、(44.9±8.2)%和(1.3±1.1)%增加到(89.3±9.5)%、(50.1±7.2)%、(57±9.0)%和(37.0±12.7)%。对K562细胞的杀伤效应在第4、7、13天分别为(23.6~8.5)%、(56.4±7.2)%和(80.1±4.5)%。【结论】rhIFN-γ,rhIL-2和Anti-CD3mAb诱导恶性实体瘤患者外周血单个核细胞活化为以CD34^+CD16^+CD56^+为主的细胞因子诱导的杀伤细胞,细胞增殖力强,并对K562细胞有强大的杀伤活性。  相似文献   
999.
BACKGROUND: As the definitional formula for population attributable fraction is not usually directly usable in applications, separate estimation formulas are required. However, most epidemiology textbooks limit their coverage to Levin's formula, based on the (dichotomous) distribution of the exposure of interest in the population. Few present or explain Miettinen's formula, based on the distribution of the exposure in the cases; and even fewer present the corresponding formulas for situations with more than two levels of exposure. Thus, many health researchers and public health practitioners are unaware of, or are not confident in their use of, these formulas, particularly when they involve several exposure levels, or confounding factors. METHODS/RESULTS: A heuristic approach, coupled with pictorial representations, is offered to help understand and interconnect the structures behind the Levin and Miettinen formulas. The pictorial representation shows how to deal correctly with several exposure levels, and why a commonly used approach is incorrect. Correct and incorrect approaches are also presented for situations where estimates must be aggregated over strata of a confounding factor.  相似文献   
1000.
Tinnitus has been challenging to treat with consistently positive results. The Neuromonics Tinnitus Treatment is a newly available approach to the treatment of clinically significant, problematic tinnitus (and reduced sound tolerance) that was developed with the intention of simultaneously addressing the auditory, attentional, and emotional processes underlying the condition. It uses a prescribed acoustic stimulus, customized for each patient's individual audiometric profile, which provides a broad frequency stimulus to address the effects of auditory deprivation, promotes relief and relaxation with the intention of reducing engagement of the limbic system/amygdala and autonomic nervous system, and applies the principles of systematic desensitization to address the attentional processes. This article describes the underlying principles behind this approach. It also summarizes evidence for clinical efficacy from controlled clinical studies and from a private practice clinical setting, where it has been shown to provide consistently positive outcomes for patients meeting suitability criteria.  相似文献   
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