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91.
The present paper delineates and discusses eight parameters of response-contingent time out (TO) procedures that need to be considered in treating children and conducting research. In general, the parameters have not been systematically controlled or investigated.  相似文献   
92.
BACKGROUND: Computer-based simulated biologic neural network models have made significant strides in clinical medicine. METHODS: To determine the predictive performance of a conventional regression model and an artificial neural network for estimating urea nitrogen appearance (UNA) during critical illness, 125 adult patients admitted to the trauma intensive care unit who required specialized nutrition support were studied. The first 100 consecutive patients were used to develop the 2 models. The first model used stepwise multivariate regression analysis. The second model entailed the use of a feeding-forward, back-propagation, supervised neural network. Bias and precision of both methods were evaluated in 25 separate patients. RESULTS: Multivariate regression analysis revealed a significant highly correlative relationship (r(2) = .918, p < or = .01): Predicted UNA (g/d) = (0.29 x WT) + (1.20 x WBC) + (0.44 x SUN) with WT as current body weight in kg, WBC as white blood cell count in cells/mm(3), and SUN as serum urea nitrogen concentration (mg/dL). The regression method was biased toward overestimating measured UNA, whereas the neural network was unbiased. Precision (95% confidence interval) of the neural network was significantly better than the regression (3.3-7.2 g vs 7.3-11.6 g, respectively, p < .01). Regression analysis successfully predicted UNA within 3 g of measured UNA in 16% (4 of 25) of patients, whereas the neural network successfully predicted UNA in 44% (11 out of 25) of patients (p < .06). CONCLUSIONS: These preliminary data indicate that use of an artificial neural network may be superior to conventional regression modeling techniques for estimating UNA in critically ill adult multiple-trauma patients receiving specialized nutrition support.  相似文献   
93.
The frequency of infections by Candida species is increasing worldwide, with candidemia representing the fourth most common bloodstream infection in the U.S. The risk of infection is especially high in the immunocompromised, hospitalized patient. The treatment of and prophylaxis for Candida infection have led to the emergence of resistant species and the acquisition of resistance in previously susceptible species. Current therapeutic options include amphotericin B and its lipid compounds, fluconazole, itraconazole, voriconazole, and caspofungin. Research is focusing on better diagnostics and the evaluation of strategies such as prophylaxis in high-risk hosts and pre-emptive therapy.  相似文献   
94.

Background

The Rh blood system is one of the most polymorphic and immunogenic systems known to humans. The expression of Rh blood group antigen is complex. The Rh D antigen is the most important of the antigens that constitute the Rh antigen system. In most cases, D antigen can easily be detected. However, due to variability of expression, weak forms antigen are encountered. The reactivity of weak D with antisera is variable and presents as a problem in blood banking.

Methods

A retrospective analysis for a five-year period was done. Blood samples that were negative for Rh D by immediate spin tube method were tested for weak D antigen by additional lab tests.

Result

Of 34932 serial Rh grouping tests done in our Blood Bank, the incidence of weak D Rh antigen was 0.189%. All these were confirmed by the antiglobulin test.

Conclusion

These patients present as a problem for the blood banker and a curiosity to the clinician. Although uncommon, all health care workers should be aware of this entity to avoid anti D alloimmunisation.Key Words: Weak D, Rh Blood Group  相似文献   
95.
Celiac disease CD is an inflammatory disease of the small intestine brought about by exposure to gluten in genetically predisposed individuals. Celiac disease most often presents with non specific, or extra-intestinal, manifestations and, consequently, the disease remains under diagnosed. Untreated CD is associated with high morbidity and, therefore, early diagnosis is essential. The availability of non-invasive and relatively cheap serological tests has made it possible to screen large numbers of patients and resulted in increased, and earlier, diagnosis of patients with CD. However, these tests have varying degrees of sensitivities and specificities and the results generated can lead to a lot of confusion with regards to the diagnosis, or exclusion, of CD. In the present review, we discuss in detail these tests and suggest how they can be used in screening patients for CD with the hope that such information will help clinicians to select the right tests and interpret the generated results more effectively, and thus lead to improved identification and treatment of patients with CD.  相似文献   
96.
We studied the prevalence of musculoskeletal conditions in a rural Oregon primary care practice and the self-assessed musculoskeletal knowledge and skills of primary physicians practicing in the area. We recorded how many musculoskeletal complaints were evaluated and treated in a primary care physician's office between April 1 and April 30, 2002. In addition, to all primary care physicians in the surrounding county, we distributed a self-administered questionnaire assessing physician confidence regarding common musculoskeletal conditions and procedures. Prevalence of musculoskeletal conditions for the month was 17.5% (48/274 office visits). Questionnaire results indicated that local physicians felt relatively uncomfortable with common musculoskeletal conditions (mean confidence scores on a 10-point Likert scale: 4.2, musculoskeletal conditions; 9.0, nonmusculoskeletal medical conditions). These findings suggest a disparity between rural primary care physicians' self-assessed musculoskeletal knowledge and skill and the levels they require for their practice.  相似文献   
97.
Dehydration is a serious risk for the long-term tube-fed patient who is not allowed oral intake, has an altered mental status, is unable to communicate, is elderly or fluid-restricted, or has thirst impairment. The intent of this review is to provide a case-based discussion regarding the evaluation, treatment, and prevention of dehydration in these types of patients. Identification of risk factors, along with evaluation of subjective, objective, and laboratory parameters, provides the basis for clinical evaluation. "Hidden" sources of fluid intake such as the water content of solid foods and water generated from nutrient oxidation and "hidden" sources of fluid output such as evaporative losses should be considered in waterbalance calculations. The method for treatment and prevention of dehydration depends on the presence or absence of hypovolemia, type of body fluid losses, and whether the patient demonstrates hypernatremia, normonatremia, or hyponatremia.  相似文献   
98.
Context  The "hygiene hypothesis" has implicated sibship as a marker of infection load during early life and suggests that exposure or reexposure to infections can influence the developing immune system. Viral infection has also been implicated in the pathogenesis of multiple sclerosis (MS). Objectives  To evaluate whether exposure to infant siblings in early life is associated with the risk of MS, and to explore the possible mechanism for any apparent protective effect, including altered Epstein-Barr virus (EBV) infection patterns. Design, Setting, and Patients  Population-based case-control study in Tasmania, Australia, from 1999 to 2001 based on 136 cases of magnetic resonance imaging–confirmed MS and 272 community controls, matched on sex and year of birth. Main Outcome Measure  Risk of MS by duration of contact with younger siblings aged less than 2 years in the first 6 years of life. Results  Increasing duration of contact with a younger sibling aged less than 2 years in the first 6 years of life was associated with reduced MS risk (adjusted odds ratios [AORs]: <1 infant-year, 1.00 [reference]; 1 to <3 infant-years, 0.57 [95% confidence interval {CI}, 0.33-0.98]; 3 to <5 infant-years, 0.40 [95% CI, 0.19-0.92]; 5 infant-years, 0.12 [95% CI, 0.02-0.88]; test for trend, P = .002). A history of exposure to infant siblings was associated with a reduced IgG response to EBV among controls. Controls with at least 1 infant-year contact had a reduced risk of infectious mononucleosis and a reduced risk of very high composite EBV IgG titers (AOR, 0.33; 95% CI, 0.11-0.98) compared with other controls. The inverse association between higher infant contact and MS was independent of EBV IgG titer. Conclusion  Higher infant sibling exposure in the first 6 years of life was associated with a reduced risk of MS, possibly by altering childhood infection patterns and related immune responses.   相似文献   
99.
College students and a subsample of their mothers and fathers participated in a study examining their retrospective reports of childhood emotional and behavioral problems experienced by college students. College students and their mothers and fathers exhibited moderate correspondence in their recollection of internalizing and externalizing problems that college students experienced during their childhood. In contrast, college students tended to endorse significantly greater levels of both internalizing and externalizing problems relative to their mothers and fathers. Current psychological symptoms predicted the greater endorsement of childhood internalizing and externalizing problems by college students and the greater endorsement of college students' childhood internalizing problems by their mothers. Further, college students' current perceptions of their parents predicted their endorsement of childhood internalizing problems, and college students' current masculinity and femininity predicted their endorsement of childhood externalizing problems. Results of this study emphasized the importance of noting factors that may be related to retrospective reports.  相似文献   
100.
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