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51.
Prior studies have shown that pneumothorax is one of the more difficult entities to diagnose with digitized radiography. This study was designed to test whether increasing resolution from 1.25 to 2.5 line pairs per millimeter (lp/mm) and image processing (edge enhancement from unsharp masking) would increase accuracy and confidence in the diagnosis of pneumothorax, as well as normal cases and other forms of lung disease. Conventional radiographs were digitized with use of a laser reader and then reformatted as film hard copy. Eleven observers read 35 cases reformatted in three different ways (1.25 lp/mm, 2.5 lp/mm, 1.25 lp/mm unsharp mask). The images with finer resolution (2.5 lp/mm) and unsharp mask images were superior to those with coarser resolution (1.25 lp/mm) for the diagnosis of pneumothorax. There was no difference in diagnostic accuracy for normal patients. For abnormalities other than pneumothorax, the unsharp mask images were significantly worse. Confidence in the diagnosis of pneumothorax and other abnormalities was highest with the finest resolution (2.5 lp/mm). 相似文献
52.
S R Tabet D L Palmer W H Wiese R E Voorhees D R Pathak 《American journal of public health》1992,82(8):1151-1154
A survey of persons soliciting sex in an area known to be frequented by prostitutes in Albuquerque, NM, included 43 females and 66 males. Seroprevalence rates found in this population-based study were as follows: human immunodeficiency virus type 1 (HIV-1), 3%; hepatitis B, 39%; hepatitis C, 45%. Increased age, intravenous drug use, and condom use were independent risk factors for hepatitis B. Female gender and intravenous drug use were independent risk factors for hepatitis C. Neither sharing injection equipment nor engaging in receptive anal intercourse was independently associated with hepatitis B or C. 相似文献
53.
54.
The pharmacokinetics of ondansetron after intravenous injection in healthy volunteers phenotyped as poor or extensive metabolisers of debrisoquine. 总被引:2,自引:1,他引:1
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E I Ashforth J L Palmer A Bye A Bedding 《British journal of clinical pharmacology》1994,37(4):389-391
The pharmacokinetics of the 5-HT3 receptor antagonist ondansetron following an 8 mg i.v. dose were investigated in 12 subjects previously phenotyped with debrisoquine. Six subjects were poor metabolisers (debrisoquine metabolic ratios 29-131) and six were extensive metabolisers (debrisoquine metabolic ratios 0.45-3.4). There was no significant difference in AUC, Cmax, CL or t1/2 between the poor and extensive metabolisers. It is concluded that ondansetron clearance is not mediated exclusively by cytochrome P-450 2D6. 相似文献
55.
Robert M. Palmer Steven R. Counsell Seth C. Landefeld 《Disease Management & Health Outcomes》2003,11(8):507-517
Older patients often experience a loss of independent physical functioning during the course of an acute illness that requires hospitalization. Although functional outcomes are not usually the focus of care in the hospital, they may be critical determinants of the quality of life, physical independence, cost of care, and prognosis among older patients.Based on a conceptual model of the dysfunctional syndrome (functional decline associated with hospitalization) we developed, implemented and evaluated a multi-component intervention termed Acute Care for Elders (ACE), in hospital medical units of two urban hospitals. ACE is a model of care that combines the principles of geriatric assessment and quality improvement. The ACE intervention includes a prepared environment (environmental modification), patient-centered care (interdisciplinary assessment), interdisciplinary team rounds and planning for home, and medical care review. Results of randomized clinical trials support the effectiveness of ACE to improve outcomes of hospitalization for older patients. Improved functional status, lower risk of nursing home placement and higher levels of patient and professional satisfaction with care are achievable with ACE.The challenges of establishing an ACE unit in community hospitals can be met through a systematic process of implementation and evaluation.ACE is a multi-component intervention that is potentially transportable to other hospital units, with benefits for patients, health professionals and hospital administrators. 相似文献
56.
Chronic periodontitis results in the destruction of the collagen fibre attachment to cementum, apical migration of the epithelial attachment, contamination of the exposed root surface by plaque and loss of alveolar bone. Regeneration can be defined as the restitution of lost tissues to a state which existed before destruction. As such, it is an ultimate and ideal goal and in most circumstances is currently beyond our capabilities. However, research in periodontology over the last 10 years or so has made considerable advances and is perhaps unique in proposing a new and fundamental treatment modality--guided tissue regeneration. 相似文献
57.
Effective high-capacity gutless adenoviral vectors mediate transgene expression in human glioma cells. 总被引:2,自引:0,他引:2
Marianela Candolfi James F Curtin Wei-Dong Xiong Kurt M Kroeger Chunyan Liu Altan Rentsendorj Hasmik Agadjanian Lali Medina-Kauwe Donna Palmer Philip Ng Pedro R Lowenstein Maria G Castro 《Molecular therapy》2006,14(3):371-381
Glioblastoma multiforme (GBM) is the most common subtype of primary malignant brain tumor. Although serotype 5 adenoviral vectors (Ads) have been used successfully in clinical trials for GBM, the capacity of Ads to infect human glioma cells and the expression of adenoviral receptors in GBM cells have been challenged. In this report, we studied the expression of three molecules that have been shown to mediate adenoviral entry into cells, i.e., coxsackie and adenovirus receptor (CAR), integrin alphavbeta3 (INT), and major histocompatibility complex class I (MHCI), in rodent glioma cell lines and low-passage primary cultures and cell lines from human GBM. We correlated levels of expression of CAR, INT, and MHCI with transduction efficiency elicited by several high-capacity helper-dependent adenoviral vectors (HC-Ads). Expression levels of adenoviral receptors were variable among the different GBM cells studied. HC-Ad-mediated therapeutic gene expression was efficient, ranging between 20 and 80% of the total target cells expressing the encoded transgenes. Our results show no correlation between the levels of CAR, INT, or MHCI molecules and the levels of transgene expression or the number of GBM cells transduced. We conclude that expression levels of adenoviral receptors do not predict their transduction efficiency or biological function. 相似文献
58.
Familial Pick''s disease and dementia in frontal lobe degeneration of non-Alzheimer type are not variants of prion disease.
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![点击此处可从《Journal of neurology, neurosurgery, and psychiatry》网站下载免费的PDF全文](/ch/ext_images/free.gif)
59.
Dr. Ronald L. Bauer MD Michael L. Palmer MD Andrea M. Bauer MSN RN CS Hector R. Nava MD Harold O. Douglass Jr. MD 《Annals of surgical oncology》1994,1(3):183-188
Background: The purpose of this study was to evaluate the tumor characteristics and treatment associated with an improved overall survival in patients with adenocarcinoma of the small intestine.
Methods: The records of all patients with primary adenocarcinoma of the small bowel seen between January 1971 and December 1991 were reviewed retrospectively. The study comprised 38 patients, 22 (58%) with duodenal tumors, 11 (29%) with jejunal tumors, and five (13%) with ileal tumors.
Results: Although not statistically significant, the patients with duodenal adenocarcinoma lived longer than the patients with jejunal or ileal lesions (p=0.77). The overall survival was 23% and seemed to correlate best with absence of lymph node metastases (p=0.04) and pancreaticoduodenectomy for localized duodenal tumors (p=0.04). The patient's age, duration of symptoms, disease-free interval, tumor location, type of recurrence, and histologic grade did not significantly influence survival.
Conclusions: The lethality of small-intestinal adenocarcinoma appears to be related to a delay in diagnosis and treatment. When a definitive surgical procedure is performed before lymph node metastases appear, the patient's chance for long-term survival is greatly improved.Presented at the 46th Annual Cancer Symposium of The Society of Surgical Oncology, Los Angeles, California, March 18–21, 1993. 相似文献
60.