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91.
N. J. Carty B. Moran C. D. Johnson 《Annals of the Royal College of Surgeons of England》1994,76(4):276-280
This article examines whether there is any clinical value in anorectal physiology measurements. The function of the human rectum is poorly understood and the factors which affect function of the anal sphincters are complex. Several laboratories have reported results of anorectal physiology measurements, but there is extensive variation between normal values in different laboratories. It is argued that anorectal physiology measurements fail to meet the criteria of a useful clinical test: 1. It is not widely available to clinicians; 2. It is not possible to establish a reproducible normal range; 3. Abnormal measurements do not correlate with disease entities or explain symptoms; 4. The results are often unhelpful in diagnosis and management; 5. Clinical outcome after intervention does not correlate with alteration in the measurements obtained. On the other hand it can be argued that anorectal physiology measurements do provide information that assists in the management of conditions such as constipation, anismus, Hirschsprung''s disease, faecal incontinence and tenesmus. Management based on biofeedback modification of physiological responses requires these techniques as part of the biofeedback system. There is evidence that this may be appropriate in anismus and solitary rectal ulcer syndrome. However, the assessment of these difficult conditions and the interpretation of the results are probably at present best confined to specialist units. 相似文献
92.
Infantile myofibromatosis is a mesenchymal tumor most commonly seen in infancy. The tumors have a variable appearance on
CT/MR and often simulate a more aggressive neoplasm. This report describes CT/MR findings in cases of infantile myofibromatosis
with pathologic correlation. Discussion into the success of imaging in suggesting the correct diagnosis is also addressed.
Infantile myofibromatosis is a mesenchymal disorder of infancy characterized by the presence of tumorous nodules in the skin,
subcutaneous tissue, muscle, viscera, and bone. Cases of solitary and multiple lesions have been described. We present the
clinical, histologic, and radiographic findings of one case of the solitary form of infantile myofibromatosis that was recently
diagnosed at our hospital. 相似文献
93.
94.
The binding of cocaine, d-amphetamine and dopamine to the site on the dopamine transporter labeled by [3H]mazindol was investigated in rat striatal membranes. N-Ethylmaleimide inhibited about 95% of the specific binding of 5 nM [3H]mazindol in a concentration-dependent manner. The effect of 10 mM N-ethylmaleimide was completely prevented by cocaine (EC50 of 3 microM), but neither 300 microM dopamine nor d-amphetamine afforded any significant protection. On the other hand, high concentrations of cocaine, d-amphetamine and dopamine provided similar protection against inhibition by 0.1 mM N-ethylmaleimide. Taken together these data support the hypothesis that a significant portion of the cocaine binding domain on the transporter is distinct from that of either dopamine or amphetamine. This distinction may be sufficient to allow properly designed drugs to prevent cocaine binding without inhibiting DA transport. 相似文献
95.
An assessment was made of 129 faculty who teach nursing students about the care of aged clients to determine their level of interest and expertise in 21 content areas related to gerontology. Faculty rated their expertise consistently lower than the relevance of, and their interest in, each of the content areas. Areas identified as most important for their professional growth tended to be areas where faculty ranked their expertise as already being high. The mean self-rated expertise of faculty who taught a course in gerontological nursing was significantly higher than those who did not. Most respondents lacked formal education in gerontology: 9% of respondents had gerontology in their undergraduate program; 27% in their graduate program. Only 4% were certified as gerontological nurses or gerontological nurse practitioners. 相似文献
96.
97.
E.M. Smith Ph.D. S.R. Johnson M.D. E.J. Figuerres M.S. M. Mendoza M.S. D. Fedderson B.S. T.H. Haugen M.D. L.P. Turek M.D. 《Gynecologic oncology》1997,65(3):441-446
Postmenopausal women enrolled in the Iowa portion of the postmenopausal estrogen/progestin interventions randomized clinical trial (n= 105) during 1989–1991 were studied for (i) the prevalence of human papillomavirus (HPV) in this older age population (ages 45–64), and (ii) the association between hormone replacement therapies (HRTs) and changes in detection of HPV over a 2-year time period. HPV is causative in most cervical and some other genital cancers and in the presence of steroid hormones has been shown to increase neoplastic transformation by HPVin vitro.Using PCR to detect HPV DNA, the overall frequency of the virus regardless of time period was 50.3% (n= 53) with a baseline (BL) frequency of 38.1% and the second year follow-up (FU) of 22.9%. The oncogenic types HPV-16 (75.5%) and HPV-31 (20.8%) were the most commonly reported. All those with persistently detected infection (10.5%), defined as HPV+ at both BL and FU, were identified with HPV-16 or -18. Between these two time periods there were no significant differences in HPV frequency between the placebo and combined HRT groups (BL−/FU+, 21% vs 18%; BL+/FU−, 71% vs 80%). While the study is based on a small sample, the findings suggest that short-term use of HRTs is not associated with an increased risk of HPV detection, but assessment of effects from long-term use is needed. The data also indicate that the frequency of HPV found in older women is higher than previously suspected but that short-term changes in HPV detected in this age group are unrelated to the development of precancerous cervical lesions. 相似文献
98.
J. Keith Smith M.D. Ph.D. Gordon C. Carson III M.D. Jay D. Johnson B.S. John H. Harris Jr. M.D. D.Sc. F.A.C.R. 《Emergency radiology》1994,1(2):78-80
Purpose: To describe an educational computer aided instruction program dealing with diagnosis and classification of facial
fractures.
Methods: A program was created for use on Macintosh computers using a graphic presentation package. This program allows for
the display of high resolution digitized radiographic images and illustrations, along with integrated voice and text information.
Users can interact with the program to review complex concepts or study additional cases. Case material was obtained from
selected high quality plain radiographs and computed tomography (CT) scans obtained in the trauma center of one institution,
and was scanned on a high resolution digital scanner with image parameters optimized for viewing on the Macintosh high resolution
color monitor.
Results: The program has been installed in the computer aided instructional laboratories or trauma centers at The University
of Texas Health Science Center, Houston; The University of Alabama, Birmingham; Emory University School of Medicine, Atlanta,
Georgia; and The University of North Carolina, Chapel Hill. The program is available to radiology residents and medical students
rotating on the trauma radiology services at these institutions. Completion of the program requires 30–45 minutes.
Conclusion: Based on our initial experience, the program has been used by residents in the training programs of all institutions
with favorable results. 相似文献
99.
R. Ehrlich R. J. Wenning G. W. Johnson S. H. Su D. J. Paustenbach 《Archives of environmental contamination and toxicology》1994,27(4):486-500
The identity and relative contributions of various sources of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) to recently deposited sediments collected in Newark Bay and its major tributaries were determined using polytopic vector analysis (PVA), a multivariate statistical technique relatively new in the chemometric literature. The concentrations of 2,3,7,8-substituted PCDD/Fs were assayed in eighty-one surface and near-surface sediment samples collected from the Passaic River, Hackensack River, Arthur Kill, Elizabeth River, Kill Van Kull, Port Elizabeth, and Port Newark navigation channels and Robins Reef, which is located in New York Harbor. PVA modeling revealed five predominant 2,3,7,8-substituted PCDD/F fingerprint patterns in geographically plausible distributions throughout the estuary. This was consistent with the current understanding of hydrodynamic and sedimentation conditions reported in the literature for Newark Bay. Three patterns contained 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD), which is alleged to originate from a single industrial source on the lower Passaic River. One of the fingerprints containing 2,3,7,8-TCDD was present in moderate proportions (10–20%) in surface sediments near the site, but was generally observed in low abundance (<5%) elsewhere in the estuary. A fingerprint pattern characteristic of PCDD/F profiles in effluents from municipal sewage and waste water treatment plants was widely distributed in the estuary, but reached its highest relative proportions in the Elizabeth River. A third fingerprint pattern was highest in the Arthur Kill and lower Passaic River and closely matched the residue patterns found in several types of combustion sources. A fourth finger-print pattern in Hackensack River and lower Passaic River sediment matched the PCDD/F profile reported in PCB Aroclor® formulations. A fifth fingerprint pattern matched the profile in recycled pulp and paper mill effluents and was highest in Kill van Kull and upper Passaic River sediment. The majority of PCDD/Fs in sediment from Reaches B, C, and D of Port Newark and Port Elizabeth were attributable to sediments transported via the Arthur Kill and the Kill Van Kull. These results are consistent with those previously reported using principal components analysis, which indicated that 2,3,7,8-substituted PCDD/F patterns in the sediments of Newark Bay are consistent with discharges from multiple sources. 相似文献