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51.
Infection with human T-lymphotrophic virus (HTLV) type 1 causes a neurological disorder or leukaemia in a minority of infected persons. Since January 1993 the Dutch blood banks screen each donation for presence of HTLV-1 infection. Approximately 4,000,000 donations from 700,000 donors have been tested. The numbers of confirmed HTLV-1 positive donors were: 1993: 15; 1994: 6; 1995: 8; 1996: 3. In 1995 one case of HTLV-2 infection was detected as well. In 26/32 (81%) of the HTLV-1 positive cases either the donor or his/her partner originated from HTLV-1 endemic areas. The introduction of HTLV screening prevents the silent spread of HTLV via blood transfusion.  相似文献   
52.
A two-year prospective study was done to assess the prevalence and distribution of various parameters associated with scoliosis in schoolchildren in northwestern and central Greece. A total of 82,901 children (41,939 boys and 40,962 girls) who were nine to fourteen years old were screened for scoliosis. Five thousand eight hundred and three children had clinical signs of scoliosis and, of these, 4185 were referred for posteroanterior radiographs (to be made with the patient standing) because they had a positive result on the forward-bending test (a difference of more than five millimeters between the two sides of the torso as measured in the thoracic or thoracolumbar region with use of a ruler and a level plane) at the time of a second screening. The prevalence of scoliosis (defined as a curve of 10 degrees or more) was 1.7 per cent (1436 of 82,901 children), and most of the curves (1255; prevalence, 1.5 per cent) were small (10 to 19 degrees). The ratio of boys to girls was 1:2.1 over-all but varied according to the magnitude of the curve (1:1.5 for curves of less than 10 degrees, 1:2.7 for curves of 10 to 19 degrees, 1:7.5 for curves of 20 to 29 degrees, 1:5.5 for curves of 30 to 39 degrees, and 1:1.2 for curves of 40 degrees or more). Thoracolumbar curves were the most common type of curve identified, followed by lumbar curves; specifically, of the 1436 children who had a curve of at least 10 degrees, 493 (34.3 per cent) had a thoracolumbar curve, 475 (33.1 per cent) had a lumbar curve, 261 (18.2 per cent) had a thoracic curve, and 207 (14.4 per cent) had a double curve. Although most (753) of these curves were to the left, the left:right ratio varied according to the location of the apex of the curve (1:3.1 for thoracic curves, 2.0:1 for thoracolumbar curves, and 3.2:1 for lumbar curves). The cost of the screening process was negligible (estimated at thirty cents per child); however, the decreased number of operative procedures performed in children from the geographical area of our University Hospital, the identification of a large number of previously undiagnosed curves (eleven of which were treated operatively and 170 of which were treated with a brace), and the identification of children who were at high risk for progression were considered important benefits of the school-screening program.  相似文献   
53.
Anticipation and suspicion are critical aspects to any discussion of intrauterine adhesions. Curettage between the second and fourth week postpartum is more likely to cause adhesions than is any other endometrial trauma. Infertility, recurrent abortion, or menstrual aberrations after any uterine trauma should cause the physician to suspect the presence of intrauterine adhesions. Hysterosalpingography and hysteroscopy are the ideal methods to make the diagnosis of IUA, and the latter is the safest, least traumatic, and most precise method of treating adhesions. The addition of an intrauterine splint and high-dose estrogen therapy completes the therapeutic approach. Before attempting conception the cavity should be inspected to verify its normality.  相似文献   
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55.
Monoarthritis     
By definition, monoarticular arthritis means one-joint involvement, even though, in fact, such a condition is often an oligoarthritis because as many as two or three separate joints will be involved. Arthritis is often limited and may regress, so that it is frequently misdiagnosed. Sometimes, a monoarticular condition may be a polyarthritis onset (i.e., rheumatoid arthritis). Monoarticular arthritis can be caused by many factors, such as infections (septic arthritis), nonspecific inflammatory processes (reactive arthritis), crystals deposition (gout, CPPD crystal deposition disease), trauma, neoplasm (pigmented villonodular synovitis), immunologic conditions (amyloidosis) and hormonal changes (parathyroid disease). Its onset is usually acute and sometimes dramatic, with fever, pain and joint swelling, so that a decision must be made promptly to stop rapid illness evolution and to prevent the irreversible destruction of cartilage and bone (especially in septic arthritis). Diagnostic studies are performed with mono-bilateral radiographs of the joint. Radiographic findings (i.e., soft tissue swelling, joint effusion, widening and thinning of joint spaces, bone erosions and destruction of bone surface) are typical of the disease, but some findings (e.g., type of evolution and progression), laboratory tests, synovial biopsy and arthroscopy can differentiate infectious from inflammatory forms. Scintigraphy can depict isotopic joint uptake, before articular abnormalities are demonstrated with radiography, thanks to its high sensitivity; nevertheless, because of its low specificity, scintigraphy may miss some kinds of lesions (including osteoarthritis) and cannot easily differentiate osteomyelitis from septic arthritis. CT and MRI play a secondary, though not negligible, role, especially to study such deep infections as psoas abscesses, which may mimic arthritides.  相似文献   
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57.
Treatment of Alzheimer's disease has in the past been limited to empirical trials of psychotropics for relief of behavioral complications. At present, tacrine and doneprezil are the only FDA-approved antidementia agents available. In the very near future, however, other cholinesterases inhibitors (e.g., ENA 713, metrifonate, long-acting physostigmine) are expected to be approved for clinical use. The evidence at this point suggests that they have modest but meaningful clinical effects and possible long-term benefits. Clinical use of the newer agents is likely to be influenced by their side-effect profiles, which consist largely of cholinergic effects, although without the hepatotoxic effects associated with tacrine. To what extent these agents are accepted by patients and physicians remains to be seen. On the one hand, benefits are modest; on the other, these medications are increasingly safe. Continuing research is clarifying the role of cholinergic therapy in relieving behavioral symptoms, as well as the possible side effects on rates of illness progression, institutionalizaton, and even mortality. In the not-too-distant future, physicians can expect to see a variety of medications, now in early stages of development, that are intended to affect cholinergic systems in other ways. Further down the road, a host of mechanism-based therapeutic strategies, which hope to deal with the first cause of this devastating illness, will have been assessed in clinical trials.  相似文献   
58.
We report a 14 year old boy who presented as a neonate with functional pulmonary atresia due to Uhl's disease with emphasis on the later detection of restrictive right ventricular physiology.  相似文献   
59.
60.
A pharmacoeconomic study of 15 antibiotics available in Barbados was performed. The antibiotics studied were amoxycillin/clavulanate, ampicillin, ampicillin/sulbactam, cefazolin, cefotaxime, ceftazidime, ceftriaxone, clindamycin, cloxacillin, cotrimoxazole, gentamicin, imipenem, metronidazole, piperacillin, piperacillin/tazobactam, and vancomycin. The costs of use of these compounds were calculated for a five-day course using a formula comprising eight categories: antibiotic purchase cost, maintenance of intravenous access, drug delivery cost, drug monitoring cost, dose readjustment, general monitoring cost, 'sharps' disposal cost and adverse effects. The costs of adverse effects were not included in this study due to lack of accurate data. The total cost of antibiotic use (in U.S. dollars) ranged from $42.52 to $463.73 per five-day course. Generic compounds were less expensive ($45.52 - $98.23) than brand-name compounds ($106.18 - $106.18 - $463.73). Antibiotic purchase costs accounted for proportions of total costs ranging from 7 to 93%. Non-drug costs represented a much greater proportion of total costs of generic compounds. For most compounds the non-drug costs were related to the frequency of dosing, but for gentamicin the non-drug costs were relatively higher because of the need for monitoring of serum gentamicin levels. Efficacy and freedom from side-effects will remain the most important determinants in the choice of antibiotic therapy. However, pharmacoeconomic analyses can provide prescribers with the information required to make cost-effective choices for treatment of their patients.  相似文献   
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