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1.
Pregnancy-induced hypertension (PIH) can be complicated by maternal or fetal thrombocytopenia, or both. In order to investigate possible immunologic causes of these thrombocytopenias, platelet-associated IgG (PAIgG) and IgM (PAIgM) were measured in mothers with PIH and in their infants and compared with those from patients with autoimmune thrombocytopenic purpura (ATP), a known immunodestructive platelet disorder. Many PIH patients (33.3%) and most ATP patients (68.1%) had elevated levels of maternal PAIgG. In both diseases, the amount of PAIgG was directly proportional with the degree of thrombocytopenia (r = 0.446 in PIH and R = 0.668 for ATP). But in neither disease did the degree of maternal thrombocytopenia correlate with the degree of neonatal thrombocytopenia (r = 0.153 for PIH and R = 0.175 for ATP). Umbilical cord samples from PIH patients contained PAIgG (53.3%) and PAIgM (53.8%), whereas the umbilical cord samples from ATP patients had elevated amounts of PAIgG but not PAIgM. PAIgM in the umbilical cord blood could not be accounted for by IgM rheumatoid factors, IgM-containing immune complexes, or non-specific adsorption because of elevated total IgM levels. The umbilical cord blood PAIgM was probably not of maternal origin because it was observed even when the maternal blood contained no PAIgM and maternal IgM is not normally transported transplacentally. Therefore, the PAIgM appears to be of fetal origin. These results suggest that both maternal and fetal immunologic mechanisms may be involved in PIH-induced thrombocytopenia; if so, this is one of the first reported examples of a possible fetal autoimmune response.  相似文献   
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J H Sunshine  R G Evens  W C Chan 《Radiology》1992,182(2):365-368
In 1982, the Graduate Medical Education National Advisory Committee (GMENAC), a prominent national panel, predicted there would be 25,650 full-time equivalent (FTE) diagnostic radiologists, a 34% oversupply, by 1990. The radiologists involved in GMENAC, however, using models developed by the American College of Radiology, projected 19,800 FTE diagnostic radiologists in 1990, which was similar to the GMENAC estimate of need. The disagreement arose principally from different assumptions about residents entering the specialty. Recent data show there actually were approximately 21,900 FTE diagnostic radiologists in 1990. The radiologists' projection was 10% below this figure; the GMENAC projection was 17% above it. GMENAC erred principally in assuming diagnostic radiology residencies would not replace general radiology residencies, but rather be an addition to them. The radiologists erred principally in their assumption about the effects of the financial problems of hospitals on the number of residency positions. Accurate long-term projection of physician supply in individual specialties may well not be feasible.  相似文献   
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Image signal-to-noise ratio (SNR) limits many MRI applications. Here we propose a method to improve SNR based on continuous sampling (CS) during each TR without significant increases in acquisition time. The general concept of CS is defined here as sampling the NMR signal immediately after slice excitation including ramp times, both the dephase and rephase lobes, the phase-encoding (PE) gradient application, and the slice refocusing gradient. This study analyzes several cases of CS and demonstrates a specific case where sampling occurs during an isolated and balanced readout gradient in order to increase SNR in a rectilinear Cartesian sequence without significantly increasing overall acquisition time. The noise correlation consequences of rectilinear CS are mathematically derived and proven through simulation. The SNR improvement of up to approximately 40% measured in both phantom and asymptomatic human volunteer images is comparable to theoretical prediction of increased SNR proportional to the increase in the square root of the sampling time.  相似文献   
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Studied children with mild to moderate juvenile rheumatoid arthritiswho were massaged by their parents 15 minutes a day for 30 days(and a control group engaged in relaxation therapy). The children'sanxiety and stress hormone (cortisol) levels were immediatelydecreased by the massage, and over the 30-day period their paindecreased on self-reports, parent reports, and their physician'sassessment of pain (both the incidence and severity) and pain-limitingactivities  相似文献   
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H Lepor  G Knapp-Maloney  H Sunshine 《The Journal of urology》1990,144(6):1393-7; discussion 1397-8
The efficacy and safety of terazosin, a selective long-acting alpha-1-adrenergic blocker, were evaluated in 45 normotensive patients with symptomatic benign prostatic hyperplasia ranging from 50 to 76 years old. All patients underwent a complete urodynamic evaluation and transrectal prostatic ultrasonography before enrollment into the study. The dose of terazosin was titrated to 5 mg. per day for a 1-month interval, provided adverse drug reactions were not observed. Of the patients 39 (87%) completed the dose titration study. The parameters used to assess the effectiveness of terazosin included peak and mean urinary flow rates, micturition symptom scores and the global assessment by the patient of symptomatic improvement. Over-all, the mean systolic and diastolic blood pressures changed by less than 1%. The peak and mean urinary flow rates increased by 42 and 48%, respectively. The obstructive and irritative symptom scores improved by 63 and 35%, respectively. Over-all, 30 of the 45 participants (67%) indicated that the voiding symptoms were markedly improved while on terazosin. Five patients did not complete the dose titration study due to development of adverse drug reactions, including erectile dysfunction (7%), tiredness (7%), light-headedness (4%), palpitations (4%), nasal congestion (2%) and asymptomatic hypotension (2%). There were 25 patients (55%) followed on terazosin for 4 to 10 months (mean 6.5 months). The improvements in urinary flow rates and symptom scores were maintained for this interval. Although this preliminary experience with terazosin is encouraging, the ultimate role of terazosin for the long-term treatment of benign prostatic hyperplasia needs further evaluation.  相似文献   
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Because of concern about pressures from hospitals for changes in their contracts with radiology practices, the American College of Radiology undertook a stratified sample survey of radiology practices and their contracts with hospitals in late 1989 and early 1990. After three remailings, the survey obtained 904 valid responses for a 64% response rate. It found (weighting data to represent all radiology practices in the nation) that 91% of radiology practices provide services in hospitals. There are contracts at 57% of these hospital sites, and hospitals use tax-exempt bond financing in 54% of the sites with contracts. One year is the most common duration of contracts, and 90 days is the most common cancellation period (89% of contracts can be canceled during the contract's term). Eighty-six percent of contracts are exclusive; 73% are automatically renewable ("evergreen"). Separate billing exists in well over 90% of hospitals with contracts. Two percent of contracts require radiologists to provide equipment; 4% require them to provide support staff. There are fixed-fee arrangements in 9% of contracts and percent compensation arrangements in 3%. Hospitals share in radiologists' fees as a charge for contractual privileges in 5% of contracts. Twenty-seven percent of contracts require hospital approval for radiologists' fee increases; 19% require radiologists to participate with Blue Shield or Medicare. If a contract characteristic is predominant nationally, it is predominant in every region, for solo, small, medium, and large practices, and whether or not hospitals use tax-exempt bond financing. There is, however, some modest variation in frequency of contract provisions. Multivariate analysis shows that most such variation reflects true effects of region and other variables, not statistical artifacts. Region was a statistically significant determinant of 11 of 17 contract characteristics studied. Practice size was a statistically significant determinant of only about half as many characteristics. The survey found some interference in the independence of radiology practices (e.g., required hospital approval of fee increases), questionable clauses (e.g., mandated provision of equipment), and even illegal ones (hospitals charging a fee for contract privileges). Knowledge of the survey findings can make individual radiology practices more effective in negotiations with hospitals and assist the profession in forming a strategy to oppose disadvantageous and illegal provisions.  相似文献   
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