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161.
Detection of non-palpable early splenic enlargement may aid diagnosis of primary polycythaemia (PP) and primary thrombocythaemia (PT). In this study linear spleen sizing by ultrasound has been compared with spleen volume estimation by single photon emission computerized tomography (SPECT) in 26 patients. Spleen length by ultrasound correlated well with SPECT volume estimation.
Ultrasound spleen length was also measured in 60 normal control subjects where the upper limit of the 95% reference range was 11.6 cm. Changes in spleen length with both age and body weight were substantial and overshadowed the imperfect reproducibility of this method. Therefore, interpretation of an individual's measured spleen length should be in relation to that predicted for adults of the same age and weight, particularly at the extremes of the younger, heavier patients and also the older, lighter patients.
Ultrasound spleen lengths of different patient groups (21 PP, 26 PT, 17 idiopathic erythrocytosis, 12 secondary polycythaemia, nine apparent polycythaemia) were compared both using the measured overall reference range and the differences from the values predicted for their age and weight. The comparison showed that almost all patients with PP whose spleens were not palpable had spleen lengths greater than the upper limit for the normal control group, but separation from the other patient groups was incomplete.
Detection of non-palpable splenomegaly by ultrasound length should remain a 'minor' criterion amongst the 'proposed modified diagnostic criteria' of PP.  相似文献   
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The present study explored the role of murine monocyte chemotactic protein (MCP) in the T cell-mediated hypersensitive granulomatous response to Schistosoma mansoni eggs. The study examined the time course of local production, contribution to cellular infiltration, and the role of T cells in endogenous regulation. Synchronized pulmonary granulomas were induced under conditions of primary and secondary states of immunity. Primer-directed polymerase chain reaction analysis showed increased MCP mRNA expression in granulomatous lungs, mainly in the secondary response. Levels of MCP were measured by enzyme-linked immunosorbent assay in cultures of intact granulomas. Spontaneous MCP production was modest in primary granuloma cultures, reaching a maximum of 5.7 +/- 0.9 ng/ml by 16 days. In contrast, the secondary response showed augmented and accelerated production, achieving 13 +/- 2.0 ng/ml by 2 days. Immunohistochemical staining revealed the strongest MCP expression within microvascular adventitial cells or pericytes as well as in scattered mononuclear cells associated with granulomas. Staining was not detected in normal lungs. Passive immunization with anti-MCP-1 antibodies caused a 40% reduction in the secondary granuloma area but did not significantly affect the primary response. With adoptive cell transfer and T cell subset depletion, it was shown that Thy-1+ and CD5+ cells augmented, whereas CD8+ cells appeared to impair, MCP production. This provides direct evidence that MCP is involved in secondary Th2-mediated response to schistosome eggs and is subject to regulation by T cells.  相似文献   
167.
Owing to large differences in the incidence of AIDS (acquired immunodeficiency syndrome) and in public health resources and priorities, the impact of AIDS on state and local health departments has been variable. Nonetheless, health departments everywhere are being held responsible for surveillance and control of the HIV (human immunodeficiency virus) epidemic which we believe requires, at minimum, convenient, free HIV testing and counseling; expanded HIV services in sexually transmitted diseases clinics and substance treatment centers; locally oriented AIDS information/education; notification of persons unknowingly exposed to HIV; restrictive measures for HIV-infected persons who, after counseling, persist in exposing others; regulation or closure of public establishments in which HIV transmission is likely to result; and confidential reporting of all HIV test results to public health departments. In Colorado new legislation was passed to require reporting of HIV test results, to provide the reports with near absolute protections against unauthorized disclosure, and to modify quarantine statues to incorporate rights to due process, appeals, and confidentially. States in which there is a legal basis for discrimination against gay men will need to rectify this problem first. There is no evidence that reporting of HIV infections in Colorado has adversely affected the rate at which persons with HIV risk behaviors volunteer to be tested. For Denver and Colorado Departments of Health, more than 70 per cent of the estimated $2,796,000 expended in AIDS activities during 1987 was federal.  相似文献   
168.
Selective protection of the normal host tissues from the toxic effects of anticancer agents would allow the use of higher, probably more effective, doses of the drugs. It has been demonstrated that delayed high-dose uridine administration after 5-fluorouracil decreases the extent of myelosuppression and causes faster regeneration of the bone marrow. We studied the biochemical consequences of the gastrointestinal toxicity caused by 5-fluorouracil and the potential of high-dose uridine treatment to influence these adverse effects. 5-Fluorouracil caused dose-related decreases in the biochemical parameters (thymidine kinase, sucrase, maltase, alkaline phosphatase) selected as early markers of the impaired metabolic activity of the intestinal mucosa. The nadir of the biochemical changes was reached between 24 h and 72 h after 5-fluorouracil treatment, and complete regeneration of the mucosa took 6–7 days. Delayed high-dose uridine administration failed to mitigate the severity of the gastrointestinal damage that ensued after 5-fluorouracil treatment, but caused significantly earlier regeneration of the mucosa.  相似文献   
169.
In 82 CHD male patients aged 35-54 years with well-preserved working capacity (threshold load, 600-750 kgm/min) who had underwent bicycle ergometer test, the time course of changes in the major hemodynamic parameters was found to be significantly similar to that of healthy individuals. The cases who stopped performing bicycle ergometer tests because of anginal attacks, and ST segment depression or either showed a more significant elevation in systolic and diastolic blood pressure at the maximum load rate and lower increase in heart rate than in healthy subjects, which may be regarded as a compensatory mechanism that prevents a further decrease in coronary flow. Diminished increase in stroke index and cardiac index suggests reduced myocardial contractility.  相似文献   
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