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1.
The efficacy of radiology in evaluating dysphagia was studied in 86 patients by comparison to endoscopic findings. In the 66 patients with endoscopic abnormalities radiology was correct in 54, for a sensitivity of 82%. Sensitivity of radiology improved to 95% if mild esophagitis was excluded. In the 20 patients with normal endoscopy, radiology was normal in 18 (90%). Thus radiology proved to be a reliable means of evaluating the esophagus in patients with dysphagia.  相似文献   
2.
BACKGROUND: There are obvious advantages to increasing donor retention. However, for reasons of blood safety, certain donors may, in fact, be more desirable to retain than others. “Safe” donors are defined as those who provided a blood donation that was negative on all laboratory screening tests and who subsequently reported no behavioral risks in response to an anonymous survey. This study identifies the most important factors affecting the intention of “safe” donors to provide another donation. STUDY DESIGN AND METHODS: An anonymous survey asking about donation history, sexual history, injecting drug use, and recent donation experience was mailed to 50,162 randomly selected allogeneic donors (including directed donors) who gave blood from April through July or from October through December 1993 at one of the five United States blood centers participating in the Retrovirus Epidemiology Donor Study. Before mailing, questionnaires were coded to designate donors with nonreactive laboratory screening tests at their most recent donation. RESULTS: A total of 34,726 donors (69%) responded, with substantially higher response among repeat donors. According to reported intentions only, the vast majority of “safe” donors indicated a high likelihood of donating again within the next 12 months. Only 3.4 percent reported a low likelihood of donating again. A comparison of those likely to return and those unlikely to return reveals significant differences in demographics and in ratings of the donation experience. A higher proportion of those unlikely to return were first-time donors, minority-group donors, and donors with less education. The highest projected loss among “safe” donors was seen for those who gave a fair to poor assessment of their treatment by blood center staff or of their physical well-being during or after donating. CONCLUSION: These data suggest that efforts to improve donors' perceptions of their donation experience, as well as attention to the physical effects of blood donation, may aid in the retention of both repeat and first-time donors.  相似文献   
3.
Alternative treatments such as troleandomycin methotrexate, gold, and intravenous gamma globulin are sometimes considered for severe asthmatics to minimize the need for systemic corticosteroids and reduce adverse effects. These alternative therapies may also be associated with significant toxicity and expense. The ability to reduce corticosteroid use and the need for alternative treatment interventions in 125 pediatric patients at our institution were reviewed. Because corticosteroid requirements were reduced significantly, only 23 of 125 children evaluated were considered for treatment alternatives with only 10 receiving such therapy. This study emphasizes the importance of a thorough and comprehensive review of corticosteroid requirements and usage prior to initiating alternative approaches to treatment in moderate to severe asthmatics as well as in patients thought to be “steroid-dependent.”  相似文献   
4.
5.
Services for older people in many countries now appear to have strong similarities. There are, however, important differences in the directions and emphases of these services. This article examines factors related to differing trends in the development of services in the United States and West Germany, two countries that currently have major economic, social, and political commonalities. The differing historical development of these two countries is traced and related to the structure of services for the elderly, the role of professionals in developing these services, and the relative emphases on primary, secondary, and tertiary prevention. Predictions of future trends in services for older persons in the two countries are also explored.  相似文献   
6.
We report five patients with normal diuretic renograms who underwent Whitaker pressure perfusion testing. They were found to have normal pressure at low flow rates (2-4 ml/min) and an abnormally elevated pressure at high flow rates (8-10 ml/min). Because of persistent symptoms, two patients underwent surgery, while the other three have been followed up. Our findings indicate that a negative diuretic renogram in a well hydrated patient with good renal function may not rule out low grade obstruction. Renal pelvic perfusion at low flow rates as well as high flow rates is recommended to determine better the function of the pelviureteric junction.  相似文献   
7.
Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL.  相似文献   
8.
Intracerebral vascular reactivity induced by the nitric oxide (NO) donor isosorbide dinitrate (IDN, 5 mg sublingually) is more major and longer-lasting in migraine patients who develop delayed headache in response to the drug. The headache is purportedly due to neuronally-mediated vascular mechanisms. Indomethacin inhibits prostaglandin synthesis, which is involved in NO generation. Indomethacin also decreases cerebral blood flow by constricting precapillary resistance vessels. In the present study, the hemodynamic effects of indomethacin were evaluated in migraine patients and healthy controls by means of transcranial Doppler monitoring. Indomethacin caused a significant decrease in mean flow velocity in the middle cerebral artery. This was an additional effect to the mean velocity decrease induced by IDN. The interactions between the two drugs suggest that their effects on cerebral hemodynamics (and pain) may be of relevance both in understanding the role of NO in migraine pathogenesis and in evaluating symptomatic treatments for migraine attacks.  相似文献   
9.
We examined the effects of a combined, local intra-arterial infusion of growth hormone (GH) and insulin on forearm glucose and protein metabolism in seven normal adults. GH was infused into the brachial artery for 6 h with a dose that, in a previous study, stimulated muscle protein synthesis (phenylalanine Rd) without affecting systemic GH, insulin, or insulinlike growth factor I concentrations. For the last 3 h of the GH infusion, insulin was coinfused with a dose that, in the absence of infused GH, suppressed forearm muscle proteolysis by 30-40% without affecting systemic insulin levels. Measurements of forearm glucose, amino acid balance, and [3H]phenylalanine and [14C]leucine kinetics were made at 3 and 6 h of the infusion. Glucose uptake by forearm tissues in response to GH and insulin did not change significantly between 3 and 6 h. By 6 h, the combined infusion of GH and insulin promoted a significantly more positive net balance of phenylalanine, leucine, isoleucine, and valine (all P less than 0.05). The change in net phenylalanine balance was due to a significant increase in phenylalanine Rd (51%, P less than 0.05) with no observable change in phenylalanine Ra. For leucine, a stimulation of leucine Rd (50%, P less than 0.05) also accounted for the change in leucine net balance, with no suppression of leucine Ra. The stimulation of Rd, in the absence of an observed effect on Ra, suggests that GH blunts the action of insulin to suppress proteolysis in addition to blunting insulin's action on Rd.  相似文献   
10.
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