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51.
Mendonça EA Haas J Shagina L Larson E Friedman C 《Journal of biomedical informatics》2005,38(4):314-321
Natural language processing (NLP) is critical for improvement of the healthcare process because it can encode clinical data in patient documents. Many clinical applications such as decision support require coded data to function appropriately. However, in order to be applicable for healthcare, performance must be adequate. A valuable automated application is the detection of infectious diseases, such as surveillance of pneumonia in newborns (e.g., neonates) because the disease produces significant rates of morbidity and mortality, and manual surveillance is challenging. Studies have demonstrated that automated surveillance using NLP is a useful adjunct to manual surveillance and an effective tool for infection control practitioners. This paper presents a study evaluating the feasibility of an NLP-based monitoring system to screen for healthcare-associated pneumonia in neonates. We estimated sensitivity, specificity, and positive predictive value by comparing results with clinicians' judgments. Sensitivity was 71% and specificity was 99%. Our results demonstrated that the automated method was feasible. 相似文献
52.
Molecular cloning and nucleotide sequence of the pestivirus bovine viral diarrhea virus 总被引:47,自引:0,他引:47
The RNA genome of the cytopathic NADL isolate of bovine viral diarrhea virus (BVDV) has been molecularly cloned and the nucleotide sequence determined. The cloned sequence was 12,573 nucleotides in length, corresponding to a molecular weight of 4.3 X 10(6), having a base composition of 32.2% A, 25.7% G, 22.1% U, and 20.0% C. However, the sequences at the 5' and 3' termini of the RNA have not been unequivocally established. A single major open reading frame extending the length of the molecule was found in the viral-sense (positive polarity) sequence. This open reading frame was capable of encoding 3988 amino acids, representing 449 kDa of protein. 相似文献
53.
Tickoo SK Pittas AG Adler M Fazzari M Larson SM Robbins RJ Rosai J 《Archives of pathology & laboratory medicine》2000,124(10):1440-1447
CONTEXT: Only limited information exists on the pathologic aspects of thyroid carcinomas with bone metastases, most large studies having concentrated mainly on their clinical features. OBJECTIVE: To study in detail the morphologic features of thyroid carcinomas with skeletal metastases. DESIGN: Seventy-nine cases of thyroid carcinoma with bone metastases treated at Memorial Sloan-Kettering Cancer Center, New York, NY, between 1964 and 1998 were investigated, with emphasis on the pathology of the primary and/or metastatic tumors and comparison of the morphologic features of the tumors at both the sites, wherever possible. The tumors were also compared for various clinical parameters. RESULTS: The cohort consisted of 22 papillary, 17 follicular, 16 insular, 10 anaplastic, 9 Hürthle cell, and 5 medullary carcinomas. Of these cases, 68% had poorly differentiated or undifferentiated features in the primary and/or metastatic tumors. The metastatic tumors were better differentiated than the primary in one third of the cases (6 of 18). Only one case showed a less differentiated metastasis. The overall 5- and 10-year survival probabilities after the bone metastases were 29% and 13%, respectively (Kaplan-Meier method). Although both the tumor type and differentiation seemed to affect survivals after bone metastasis (P =.007 and.012, respectively) (log-rank test), this was primarily due to the much worse prognosis in the cases of anaplastic and medullary carcinoma. Cases of Hürthle cell carcinoma showed the longest median survival. There was no significant difference in survival among patients up to or older than 45 years at the time of metastases (P =.31). CONCLUSIONS: Most thyroid carcinomas with bone metastases are of papillary type, and most have poorly differentiated or undifferentiated features. The influence of the microscopic tumor type and tumor differentiation on survival after bone metastasis primarily appears to be due to the much worse prognosis among anaplastic and medullary carcinomas. Age at diagnosis of bone metastases does not influence survivals. 相似文献
54.
Resistance of Mice to Infection with Friend Disease Virus After Subcutaneous Injection of Friend Virus and Friend Spleen Cells
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C. L. Larson R. N. Ushijima S. K. Kasuga R. E. Baker M. B. Baker 《Infection and immunity》1973,8(5):708-714
Swiss mice injected subcutaneously with suspensions of spleen cells or an extract of spleens from mice infected with Friend virus develop resistance to subsequent intravenous inoculation of Friend virus. A single injection of either Friend virus or Friend cells induces resistance. Immunized mice display resistance when challenged 6 months after immunization and survive for at least 20 weeks after infection. Neutralization tests indicate that serum, but not lymphoid cells of resistant animals, can neutralize Friend virus. In vitro neutralization tests indicate that residence of virus within the peritoneal cavity of immune mice for 1 h sharply reduces the infective titer of the virus. 相似文献
55.
Steady-state visual evoked potentials reveal frontally-mediated working memory activity in humans 总被引:2,自引:0,他引:2
Steady-state visual evoked potentials (SSVEPs) reflect power changes at the stimulus driving frequency and have been used to assess brain activity reflecting cognitive processing. Only one study has demonstrated SSVEP modulation associated with working memory (WM), and none have compared the spatial localization of SSVEP modulations during WM performance with other brain imaging methods. Here we examined WM-related activity recorded with dense-array SSVEPs, analyzed using low resolution electromagnetic tomography, and compared the results to our previous findings using functional magnetic resonance imaging (fMRI). WM was associated with increased SSVEP activity over the right dorsolateral prefrontal cortex, paralleling our previous fMRI findings. Frontal WM-related SSVEP power correlated selectively with task performance. These results demonstrate the utility of SSVEPs for studying representational aspects of cognition. 相似文献
56.
Numerous apolipoproteins associate with amyloid plaques. A minor high-density lipoprotein-associated protein, glycosylphosphatidylinositol-specific phospholipase D (GPI-PLD), has recently been described by the authors and others. Since GPI-PLD is synthesized by, and secreted from, pancreatic islet beta cells, the present study examined the hypothesis that GPI-PLD associates with islet amyloid. GPI-PLD immunoreactivity was examined in pancreatic tissues from type 2 diabetic and non-diabetic humans. GPI-PLD binding to heparan sulphate proteoglycan was determined in the absence or presence of heparan sulphate or heparin. Fibril formation from human islet amyloid polypeptide was determined in the absence or presence of GPI-PLD. In non-diabetics, GPI-PLD immunoreactivity was present and co-localized with insulin, as opposed to co-localizing with amyloid in diabetics. No immunoreactivity for apolipoprotein A-I was present in islet cells or islet amyloid. Heparan sulphate proteoglycan, which is commonly present in most amyloid, bound GPI-PLD in vitro. GPI-PLD inhibited the formation of amyloid fibrils from synthetic islet amyloid polypeptide in vitro. GPI-PLD is therefore present in islet amyloid and appears to derive from local production from islets. This localization likely derives from interaction between GPI-PLD and heparan sulphate proteoglycan. Since GPI-PLD also inhibited islet amyloid polypeptide fibril formation in vitro, it is concluded that GPI-PLD may play a role in islet amyloid formation in type 2 diabetes. 相似文献
57.
Jon D Larson Shannon A Wadman Eleanor Chen Lesa Kerley Karl J Clark Mark Eide Sarah Lippert Aidas Nasevicius Stephen C Ekker Perry B Hackett Jeffrey J Essner 《Developmental dynamics》2004,231(1):204-213
We have identified the zebrafish homologue of VE-cadherin and documented its expression in the developing vascular system. The zebrafish VE-cadherin gene is specifically expressed in the vascular endothelial cell lineage beginning with the differentiation and migration of angioblasts and persists throughout vasculogenesis, angiogenesis, and endocardium development. Staining zebrafish embryos by whole-mount in situ hybridization with the VE-cadherin probe provides a method to screen embryos for vascular defects. To illustrate this utility, we used VE-cadherin expression to demonstrate a conservation of vascular endothelial growth factor-A (VEGF-A) function. The morpholino antisense oligonucleotide knockdown of VEGF-A function in zebrafish embryos results in a loss of angiogenic blood vessels, as indicated by the lack of VE-cadherin expression in the intersegmental vasculature. This loss can be restored in embryos supplemented with either zebrafish or human VEGF-A, the latter indicating that genes crucial to angiogenesis have highly conserved functional activities in vertebrates. 相似文献
58.
M Lubinsky H Zellweger L Greenswag G Larson I Hansmann D Ledbetter 《American journal of medical genetics》1987,28(1):37-43
We report on 4 sibs (2F, 2M) with Prader-Willi syndrome (PWS). Diagnosis was made clinically on the basis of history, behavior, and physical findings in 3 of the sibs. The other child had died at age 10 months with a history and clinical findings typical of first phase of PWS. Results of chromosome studies on the parents and surviving sibs were normal. The implications of this unusual familial occurrence for our understanding of PWS are discussed. 相似文献
59.
Larson P 《Positively aware : the monthly journal of the Test Positive Aware Network》1997,8(2):25-7, 43-4
People taking anti-HIV drugs face financial hardships due to the cost of the medications, and they need to make informed choices about health care, insurance, and financial benefits that fit their own situation. Social Security payments may be impacted if the patient returns to work, even for a limited time, and that in turn can jeopardize insurance coverage. With the success of new drugs, HIV is no longer automatically considered a disability. Many insurance policies, however, have clauses covering recurrent disabilities and may cover some of the retraining costs if the insured person needs to switch to a different line of work for health purposes. 相似文献
60.
Obesity and the risk of heart failure 总被引:1,自引:0,他引:1
Kenchaiah S Evans JC Levy D Wilson PW Benjamin EJ Larson MG Kannel WB Vasan RS 《The New England journal of medicine》2002,347(5):305-313