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981.
The exact location of hemorrhage complicating anticoagulant therapy is sometimes difficult to establish. We present a case in which imaging with 99mTc-labeled red cells had a significant role in the diagnosis of soft-tissue bleeding in a paraplegic patient receiving long-term anticoagulation.  相似文献   
982.
Preadmission testing programs have been developed to recognize and treat medical abnormalities prior to hospitalization, thus reducing preoperative hospital day costs. A preadmission testing program's objectives can be expanded by combining with a discharge planning program. The two programs combined can facilitate discharge planning and patient education prior to hospitalization and coordinate the nursing process. This article will discuss the purposes, organization, and benefits of a preadmission discharge planning program.  相似文献   
983.
984.
Anorectal function in the solitary rectal ulcer syndrome   总被引:8,自引:6,他引:2  
The anorectal function of nine patients with solitary rectal ulcer syndrome (SRUS) (5 F: 4 M, median age, 27 (range, 19–41 years) and nine control subjects (5 F: 4 M, median age, 47 (35–66)P<0.01) has been investigated by a new technique that radiologically visualizes the anorectum during voiding of a semisolid contrast medium, while simultaneously measuring intrarectal pressure and anal sphincter EMG activity. A degree of rectal prolapse was demonstrated in eight of the SRUS patients; six of these lesions were clinically occult. Abnormal failure of the anal sphincter to relax on voiding was present in seven of the SRUS patients. These abnormalities resulted in the SRUS patients requiring a greater increase in intrarectal pressure (median, 100 cm water) to void than the control subjects (median, 65 cm water,P<0.01). This combination of high intrarectal pressure and rectal prolapse during straining seems to be the cause of SRUS This work was supported by a grant from the Medical Research Council.  相似文献   
985.
In vitro studies established that neither cloth nor disposable diapers demonstrably contributed to the growth of Escherichia coli, Proteus vulgaris, Staphylococcus aureus, or Candida albicans when urine was present as a growth medium. In a clinical study of 166 children, the microbial skin flora of children with atopic dermatitis was compared with the flora of children with normal skin to determine the influence of diaper type. No biologically significant differences were detected between groups wearing disposable or cloth diapers in terms of frequency of isolation or log mean recovery of selected skin flora. Repeated isolation of S. aureus correlated with atopic dermatitis. The log mean recovery of S. aureus was higher in the atopic groups. The effects of each diaper type on skin microflora were equivalent in the normal and atopic populations.  相似文献   
986.
The long-held belief that degeneration of the cholinergic basal forebrain was central to Alzheimer's disease (AD) pathogenesis and occurred early in the disease process has been questioned recently. In this regard, changes in some cholinergic basal forebrain (CBF) markers (e.g. the high affinity trkA receptor) but not others (e.g., cortical choline acetyltransferase [ChAT] activity, the number of ChAT and vesicular acetylcholine transporter-immunoreactive neurons) suggest specific phenotypic changes, but not frank neuronal degeneration, early in the disease process. The present study examined the expression of the low affinity p75 neurotrophin receptor (p75(NTR)), an excellent marker of CBF neurons, in postmortem tissue derived from clinically well-characterized individuals who have been classified as having no cognitive impairment (NCI), mild cognitive impairment (MCI), and mild AD. Relative to NCI individuals, a significant and similar reduction in the number of nucleus basalis p75(NTR)-immunoreactive neurons was seen in individuals with MCI (38%) and mild AD (43%). The number of p75(NTR)-immunoreactive nucleus basalis neurons was significantly correlated with performance on the Mini-Mental State Exam, a Global Cognitive Test score, as well as some individual tests of working memory and attention. These data, together with previous reports, support the concept that phenotypic changes, but not frank neuronal degeneration, occur early in cognitive decline. Although there was no difference in p75(NTR) CBF cell reduction between MCI and AD, it remains to be determined whether these findings lend support to the hypothesis that MCI is a prodromal stage of AD.  相似文献   
987.
The ease of measurement and the quantitative nature of bone mineral densitometry (BMD) is clinically appealing. Despite BMD's proven capability to stratify fracture risk, data indicate that clinical risk factors provide complementary information on fracture susceptibility that is independent of BMD. Methods to quantify fracture risk using both clinical and BMD variables would have great appeal for clinical decision-making. We describe a procedure for quantifying hip fracture risk (5-yr and remaining lifetime) based on (1) the individual's age alone (base model, assuming average clinical risk factors and bone density), (2) incorporation of multiple patient-specific clinical risk factor data in the base model, and (3) incorporation of both patient-specific clinical risk factor data and BMD results.  相似文献   
988.
989.
Although the revision rates for modern knee prostheses have decreased drastically, the total number of revisions a year is increasing because many more primary knee replacements are being done. At the time of revision, bone loss is common, which compromises prosthetic stability. To improve stability, intramedullary stems are often used. The aim of this study was to estimate the effects of a stem, its diameter and the interface bonding conditions on patterns of the bone remodeling in the distal femur.

We created finite element models of the distal half of a femur in which 4 types of knee prostheses were placed. The bone remodeling process was simulated using a strain-adaptive bone remodeling theory. The amount of such remodeling was determined by calculating the changes in bone mineral density in 9 regions of interest from simulated DEXA scans.

The computer simulation model showed that revision prostheses tend to cause more bone resorption than primary ones, especially in the most distal regions. Predicted long-term bone loss due to a revision prosthesis with a thin stem equalled that around a prosthesis with an intercondylar box. However, strong regional differences were found- the stemmed prostheses having more bone loss in the most distal areas and some bone gain in the more proximal ones. A prosthesis with a thick stem led to an increase in bone loss. When the prosthesis-cement interface was bonded, more bone loss was predicted than with an unbonded interface. These results suggest that a stem which increases stability initially may reduce stability in the long term. This is due to an increase in stress shielding and bone resorption.  相似文献   
990.
The triphalangeal thumb-brachyectrodactyly syndrome is a very rare autosomal dominant disorder of unknown etiology characterized by an unusual pattern of limb malformations: triphalangeal thumbs and brachyectrodactyly in the hands, and ectrodactyly in the feet. In a previous report, we described the clinical and radiographical features of three related subjects with the disease and suggest that due to the unusual combination of limb defects and to its phenotypic similarity with the limb malformative pattern induced by disrupting the Hoxd13 gene in mouse, the triphalangeal thumb-brachyectrodactyly syndrome might be caused by mutations in a HOX gene. After sequencing the entire coding region of HOXD13 and the highly conserved homeodomain encoding region of HOXA13, we do not detect any deleterious mutation in any of the patients excluding that alterations at these sequences are responsible for the disease. Mutations in regulatory regions of these genes or in other genes involved in limb development might be responsible for the disease.  相似文献   
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