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51.
The authors conducted a complete audit of results of 38,633 mammographic examinations performed by 12 general radiologists during a 2-year period with a computerized reporting system. During this period, 11 group members attended 17 dedicated mammography courses. Audit results were analyzed for each radiologist and the entire group. In the 2nd year, the number of breast cancers diagnosed increased 50% (from 121 to 181), with a 6.5% increase in patient volume. Sensitivity increased from 80% to 87%, and there was no change in the positive predictive value of 32%. Median tumor size and node positivity decreased. Most major variables of population and technical factors were unchanged. Diagnostic approach was altered during the 2nd year, as shown by a 50% increase in the use of spot compression, magnification views, and sonography. Analysis of each radiologist's performance before and after attending mammography courses showed similar changes. These data suggest that dedicated mammography courses can help improve radiologists' performance and alter their interpretive approach.  相似文献   
52.
Bilateral cerebellopontine angle tumors in neurofibromatosis type 2   总被引:3,自引:0,他引:3  
In a series of over 500 cases of cerebellopontine angle tumors, 19 patients had bilateral neurinomas. Four of these tumors arose from the facial rather than the acoustic nerve. A conservative policy regarding surgery had been adopted in an effort to prevent hearing loss for as long as possible. Nevertheless, all patients operated on in this series are now totally deaf. The results of managing these patients surgically and conservatively are discussed.  相似文献   
53.
Segments of nicotinic acetylcholine receptor α sub-unit genes have been isolated from a panel of insect species by polymerase chain reaction, using degenerate oligonucleotide primers designed to recognize conserved regions of the Drosophila melanogaster ALS and SAO genes. The amplified segments encode elements of typical a-subunits anticipated to play roles in ligand binding and ion channel formation. Each is also clearly either ALS or SAD-like. The predicted protein sequences display extremely high levels of conservation (over 85% for each subtype) even though derived from very distantly related insect species.  相似文献   
54.
Acute renal failure (ARF) is a serious complication in clients who have undergone bone marrow transplantation (BMT). The majority of cases develop as a result of intrarenal damage. Renal ischemia or nephrotoxic drugs, free hemoglobin, and free myoglobin contribute to acute tubular necrosis (ATN), which is the most likely cause of ARF in BMT clients. Nursing care of hospitalized BMT clients is directed toward the prevention of ARF by identifying clients who are at risk, the early diagnosis of renal impairment, and the administration of comprehensive treatment. Nurses play a vital role in the early diagnosis of renal impairment by assessing the client's fluid status, serum and urine electrolyte levels, and daily weights. The nursing role in managing clients with ARF includes preventing drug nephrotoxicity, maintaining fluid and electrolyte balance, preventing infection, and providing emotional support.  相似文献   
55.
Steroid receptor was assessed immunohistochemically in 158 samples of normal breast for variation through the menstrual cycle. Patterns and intensity of reaction were used in a semi-quantitative scoring system to examine the influence of cycle phase, cycle type, parity and age. The changes in oestrogen receptor for natural cycle and oral contraceptive (OC) cycles indicated down-regulation by progestins. Progesterone receptor did not vary significantly in natural cycles, but increased steadily through OC cycles. This study provides strong evidence that both oestrogen and progesterone influence breast epithelium, but dissimilarities from the endometrium are apparent. The interval since pregnancy had a significant negative effect on frequency and score of oestrogen receptor and score of progesterone receptor. Multivariate analysis established the phase of cycle and OC use as independent significant influences on oestrogen receptor. The interval since pregnancy was an independent significant factor for both oestrogen and progesterone receptor presence.  相似文献   
56.
Sequential salivary gland scintigraphy with 99mTc-technetium pertechnetate (Tc-99) is a safe, minimally invasive test for study of major salivary glands. However, its relationship to salivary function has not been investigated in detail. We have investigated the relationship between major salivary gland flow rates and Tc-99 scans and developed a new rating scale using scans of a control group with normal salivary function. Salivary flow rates and Tc-99 scans were obtained from healthy, non-medicated subjects (n = 33) and from xerostomic patients (n = 22). There were significant differences between the groups for salivary flow rates and Tc-99 ratings. Significant correlations were found between salivary flow rates and Tc-99 ratings in the control and xerostomic groups. The Tc-99 rating scale proved reliable in assessing salivary dysfunction, and showed a high inter-examiner correlation. These results demonstrate the usefulness of salivary gland scintigraphy in assessing major salivary gland flow rates and the utility of a new rating scale.  相似文献   
57.
Using a mixed longitudinal design, the incidence of injuries, and the development of flexibility and isometric strength of the upper and lower limbs were studied for 2 years in 453 élite young athletes (aged between 9 and 18 years) practising football, gymnastics, swimming or tennis. The children suffered from a low incidence of injuries. Strength and flexibility did not exert a significant role in determining injuries. The rate of injury was not significantly different between the 2 years of the study. Young swimmers showed a greater generalized flexibility. Girls were more flexible than boys between the ages of 13 to 16 years. Athletic children are able to exert greater isometric strength than normal schoolchildren. Boys diverged from the normal population at 14 years, while athletic girls were stronger at all ages. Girls were stronger than boys up to age 12, who were still increasing their muscle strength at 19 years. The average maximal isometric strength exerted in both upper and lower limbs in the four sports was not significantly different. Male gymnasts over 11 years old were significantly stronger than all other athletes.  相似文献   
58.
Laboratory studies suggest that ghrelin is involved in bone metabolism, but studies of ghrelin and bone in humans are limited. We studied sex-specific associations of ghrelin with BMD, NTX, and bone loss. Ghrelin was not associated with BMD or bone loss in either sex. There was a significant inverse association with NTX in men but not in women. INTRODUCTION: Ghrelin is a gastric hormone recently shown to be associated with bone metabolism in animal and in vitro studies. Studies in humans are limited. We investigated the association of ghrelin with BMD, the bone resorption marker N-telopeptide (NTX), and bone loss in older men and women. MATERIALS AND METHODS: Participants were 977 community-dwelling men and non-estrogen-using postmenopausal women, 50-91 years of age. Plasma ghrelin was measured by radioimmunoassay from blood obtained between 1984 and 1987. Between 1988 and 1991, BMD was measured at the midshaft radius by single photon absorptiometry and at the femoral neck, total hip, and lumbar spine by DXA. Axial BMD measurements were repeated an average of 4 years later in 544 participants. Bone turnover was assessed by NTX in urine obtained at the same time as the initial BMD. Multiple regression analyses were used to test sex-specific associations of ghrelin with BMD, NTX, and bone loss in both sexes. RESULTS: No significant ghrelin-BMD or ghrelin-bone loss associations were observed in either sex, after adjusting for age and body mass index (BMI). Ghrelin was inversely associated with NTX in men and positively associated with NTX in women, independent of age. After adjusting for both age and BMI, this association reached statistical significance in men and was weakened in women. CONCLUSIONS: Ghrelin may be associated with bone turnover, but there is no evidence for an association with BMD or short-term change in BMD in older adults.  相似文献   
59.
Quantitative imaging of bremsstrahlung from pure beta emitters is proposed as a means for in vivo management of antibody therapy. The method involves the use of high-energy collimation, an empirically selected broad photon energy window to enhance detector sensitivity, and a Wiener restoration filter to compensate for system blur. The measured and filtered data were obtained for an idealized scattering medium and isolated spherical sources. An effective linear attenuation coefficient of about 0.13 cm-1 was determined from the raw image data of 32P. A coefficient of 0.14 cm-1 was determined after the images were restored using the Wiener filter. The measured attenuation was not significantly dependent on the size of the region of interest or the size of the source. Its variation was within the experimental error of measurement (+/- 5%). The measured sensitivity (6 x 10(-6) cps/Bq) was sufficient for imaging therapy doses of 32P or 90Y.  相似文献   
60.
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