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21.
Eighty patients who had undergone jejunoileal bypass for morbid obesity were examined by ultrasound at their routine follow-up visits to the clinic. Ultrasonographic evidence of intestinal intussusception was found in 15 patients (19%). Two of these patients were asymptomatic. Ultrasonographic findings were confirmed by operation in 6 patients (5 with intussusception, 1 negative).  相似文献   
22.
As the NHS adopts an information management approach to coordinated handling of total information resources, methods of systems analysis and design require assessment to ensure that they are appropriate. Mandatory use of Structured Systems Analysis and Design Methodology (SSADM) may be encouraging a damagingly narrow view of information systems. Research is described in which an holistic view of information systems is applied, allowing the needs of information users to play a stronger role in determining how information will be supplied to them. The techniques may also assist the training activities associated with implementing new systems.  相似文献   
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Serum concentrations of antigenic keratan sulphate determined by an enzyme linked immunosorbent assay (ELISA) with a monoclonal antibody were studied in patients with rheumatoid arthritis (RA), osteoarthritis, ankylosing spondylitis, other inflammatory diseases, and a large control group of women without arthritis. Mean keratan sulphate concentrations were low in 117 women with RA compared with 227 female control subjects matched for age drawn from a community survey. There were significant correlations between serum keratan sulphate concentrations in patients with RA and serum C reactive protein and the erythrocyte sedimentation rate. Serum keratan sulphate concentrations were also low in 29 men and women with ankylosing spondylitis and 29 patients with arthritis and high concentrations of C reactive protein. In 98 women undergoing an operation for benign breast disease there were decreases in serum keratan sulphate concentrations after the operation which correlated with doses in serum C reactive protein. No differences were found in keratan sulphate concentrations in 137 women with osteoarthritis compared with controls. Within the group with osteoarthritis there were no differences for the various joint groups and there was no obvious correlation with radiographic severity or progression. These findings suggest serum keratan sulphate is unlikely to be useful as a diagnostic marker in osteoarthritis or RA but indicate a role for inflammation in the regulation of cartilage loss.  相似文献   
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Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy.  相似文献   
27.
Computed tomography (CT) was performed in 42 patients with 49 clinically suspected tears of the posterior tibial tendon. Twenty-eight of the 49 suspected tears were subsequently surgically explored and repaired. Three patterns of tendon abnormalities were recognized on CT scans: type I-intact, hypertrophied, heterogeneous tendon; type II-attenuated tendon; and type III-absence of a portion of a tendon. Types I and II correlated with partial rupture seen during surgery, and type III correlated with complete rupture of the tendon. CT findings were accurate in 96% of the patients who underwent surgery. In four cases (14%), tendon rupture was seen on CT scans, but the extent of the injury was underestimated and the rupture was misclassified. Reactive periostitis of the distal tibia was seen in 71% of diseased tendons and may represent an important factor in the diagnosis of tendon rupture.  相似文献   
28.
The use of medical records in research can yield information that is difficult to obtain by other means. When such records are released to investigators in identifiable form, however, substantial privacy and confidentiality risks may be created. These risks become more common and more serious as medical records move to an electronic format. In 1996, the state of Minnesota enacted legislation with respect to consent requirements for the use of medical records in research. This legislation has been widely criticized because--it is claimed--it creates an unnecessary impediment to research. In this article, we show that these arguments rest upon misinterpretation and/or misrepresentation of the 1996 legislation. A consent requirement had actually been present in Minnesota since 1976 (though codified in a patient rights statute rather than a privacy statute). The 1996 law does not require specific consent, as often claimed, but rather only a general authorization. The campaign against the Minnesota legislation appears to have been motivated by concern with respect to the then impending federal privacy rule. The HIPAA rule, as enacted, is in fact less stringent with respect to consent than the Minnesota consent law. On the other hand, the Minnesota consent law has not been effectively applied or enforced. As we change the way we manage sensitive medical information, new efforts are needed to provide protection against the confidentiality risks in research. Patient consent is an important tool in this regard. New instrumentalities are needed to solicit and document consent.  相似文献   
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Abdominal computed tomography (CT) scans often have findings that are incidental to the reason the study was ordered. Several recent studies and reviews have addressed how these findings should be managed. This article summarizes current management strategies for several types of lesions that are commonly encountered. Some of these findings can be characterized without additional imaging (including simple renal cyst, angiomyolipoma, hepatic steatosis). Other findings are indeterminate. While some of these indeterminate incidental findings can be ignored based on statistical arguments (for example, a sharply circumscribed homogeneous low-attenuation renal lesion under 1 cm in patients without a predisposition to develop renal cell carcinoma), many may need additional imaging studies to either characterize them or demonstrate stability over time. Adhering to these strategies will hopefully reduce overutilization of imaging services while directing attention to those findings which need diagnostic or therapeutic interventions.  相似文献   
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