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51.
There are two reported cases of ependymomas arising in the pituitary fossa; one in a human, the other in a horse. Both died during their stay in hospital. The case presented here is the first published case of a patient who is well 3 months after surgery. 相似文献
52.
Herpes simplex virus-induced suppression of macrophage-mediated tumoricidal activity in murine macrophages 总被引:1,自引:0,他引:1
Herpes simplex virus (HSV) infections can enhance the progression of neoplastic diseases. Since macrophages can be activated to become tumorilytic and may figure prominently in host defense against cancer, the ability of HSV to modify macrophage-mediated tumoricidal functions was evaluated. Murine peritoneal macrophages treated with HSV could not be activated to a tumoricidal state by mouse recombinant gamma-interferon (IFN-gamma). Addition of HSV 4 h after treatment with IFN-gamma, at a time when the macrophages are fully committed to developing the cytotoxic phenotype, blocked macrophage-mediated lysis of syngeneic melanoma target cells. This inhibition of activation and cytotoxicity was not due simply to uptake of virus particles, because treatment with heat-inactivated HSV at 4-h posttreatment with IFN-gamma had no effect. In addition, HSV did not undergo a productive infection within macrophages, suggesting that the observed inhibitory activity might be due to a virus-induced product. In this regard, treatment of macrophages with recombinant alpha-interferon suppressed the activation of these cells by IFN-gamma, suggesting that virus-induced alpha-interferon may be mediating all or part of the suppressive activity. These studies suggest that enhancement of tumor progression following HSV infection may be related to the virus-induced suppression of macrophage-mediated tumoricidal activity. 相似文献
53.
54.
Accuracy of fetal echocardiography 总被引:6,自引:0,他引:6
The reliability of prenatal ultrasound (US) for the detection of structural heart defects was investigated in a consecutive population of patients referred for prenatal US. Twenty-eight of 49 fetuses (57%) shown to have one or more heart defects with physical examination or autopsy were found to have congenital heart disease with prenatal US. There were 66 cardiac defects in 49 fetuses, 33 of which were entirely or partly identified (50%). Defects correctly diagnosed included hypoplasia of either ventricle, common atrioventricular canal, tetralogy of Fallot, transposition of the great vessels, and Ebstein anomaly. Defects rarely diagnosed correctly included semilunar valve stenosis, total anomalous pulmonary venous drainage, coarctation of the aorta, pulmonic atresia, atrioseptal defect, and ventricular septal defect. Many types of heart defects can be diagnosed accurately with prenatal US in a general population of patients not at high risk for congenital heart disease. Some lesions, however, were difficult to detect. 相似文献
55.
56.
Moore AD; Godwin JD; Muller NL; Naidich DP; Hammar SP; Buschman DL; Takasugi JE; de Carvalho CR 《Radiology》1989,172(1):249-254
The authors retrospectively evaluated radiographs, computed tomographic (CT) scans, and results of pulmonary function tests (when available) for 17 patients with biopsy-proved pulmonary histiocytosis X. In 11 patients, high-resolution CT was used. In 12 patients, CT demonstrated cystic air spaces, usually less than 10 mm in diameter. In three of these 12, cysts were the only abnormality, but in six others, nodules (usually less than 5 mm in diameter) were also present. Two patients had only nodules and one, only emphysema. CT showed that many lesions that appeared reticular on plain radiographs were actually cysts. CT showed no central or peripheral concentration of lesions, but it did reveal that many small nodules were distributed in the centers of secondary lobules around small airways. CT findings correlated better with the diffusing capacity (rho = -0.71) than did the plain radiographic findings (rho = -0.57). Thus, CT was better than radiography at showing the morphology and distribution of lung abnormalities. 相似文献
57.
Numerous attempts at in vitro cultivation of the leprosy bacillus have all proved to be unsuccessful. Recently, we have repeatedly isolated chemo-autotrophic nocardioform (CAN) organisms in pure culture from multibacillary cases of leprosy. We find that these resemble the leprosy bacillus in many respects and suggest that the leprosy bacillus may be closer to the genus Nocardia than to Mycobacterium, and that it may be a chemo-autotroph, requiring only simple sources of carbon and nitrogen for its growth. This is in contrast to most other human pathogens, which are heterotrophs requiring complex sources of carbon and nitrogen for their growth. This could offer a possible explanation for the repeated failure at in vitro cultivation of the leprosy bacillus. 相似文献
58.
In vitro cultures of the nocardioform bacteria from leprosy-infected tissues consisted of granules and bacilli. Inoculation of these granules into mouse footpads (MFP) produced a mild, localised, inflammation for 4-6 weeks. The granules evoked typical granulomatous response in the subcutaneous tissue and showed gradual disintegration. Infiltration of muscles, connective tissue and epithelial cells by bacillary/mycelial masses was seen very frequently, and that of nerve bundles occasionally. Plenty of mycelial tufts emanated from many 'macrophage globi'. By 6-8 months, the granules disintegrated nearly completely releasing a large number of acid-fast bacilli (AFB), single layered rings of AFB, small globi and some residual mycelia. These AFB, harvested from the MFP, were similar to or indistinguishable from the bacillary preparations from the in vitro cultures and from the leprosy bacillus obtained directly from humans or as passaged into the MFP, on the basis of many criteria studied, including the 36k gene positivity. 相似文献
59.
The immunoglobulin G subclass responses to cytomegalovirus (CMV) after red cell (RBC) transfusion were studied in 26 seropositive surgery patients and 34 transfused seropositive oncology patients. Also included as controls were 18 surgical patients who received no RBCs during surgery. None of the 78 patients studied had IgG2 to CMV before or after transfusion. The absence of a total IgG response to CMV after transfusion could not be attributed to preexisting deficiencies in one or more subclasses, because all 78 patients had similar levels of IgG1, IgG3, and IgG4 to CMV before transfusion. Discriminant analysis was used for statistical evaluation of the combined CMV subclass responses in each patient and the individual subclass responses. Individual patients responded to CMV antigens with an increase in concentration in any of the three subclasses or any combination of the subclasses, excluding IgG2. IgG subclass analysis showed that 10 of 27 patients who did not respond with at least a fourfold total IgG titer rise had a significant increase in IgG subclass antibodies to CMV. Three of 33 patients with at least a fourfold total IgG titer rise lacked a subclass response. These results suggest that the measurement of IgG subclasses may be a sensitive indicator of immune response to CMV. 相似文献
60.
In the community, acute hypoglycaemia is commonly caused by therapies for
diabetes mellitus or the excessive consumption of alcohol. Although most
episodes do not require admission to hospital, little information is
available on the causes and outcome of those that do. We retrospectively
surveyed adult patients admitted to a large urban teaching hospital with
acute hypoglycaemia in a 12-month period, identifying 56 admissions of 51
patients. Forty-one had diabetes mellitus, 33 (80%) of whom were receiving
treatment with insulin. The others had hypoglycaemia induced by excessive
consumption of alcohol or by deliberate self-poisoning with insulin. A
history of psychiatric illness and/or chronic alcoholism was common.
Neurological manifestations of hypoglycaemia were the principal reason for
admission, observed on 50 occasions (89%), and 11 events (20%) had
precipitated convulsions. Although many patients (59%) had received
treatment for hypoglycaemia before admission, hypoglycaemia recurred in 16%
of patients in hospital. Four patients (7%) died following admission, but
in only one case was this the direct result of hypoglycaemia. However,
within 15 months of the index hypoglycaemia event, a further six patients
(11%) had died, mostly of causes unrelated to hypoglycaemia. Patients who
require hospital admission for treatment of hypoglycaemia have a high
incidence of neurological manifestations, a high rate of mental illness and
other medical disorders, and may represent a high-risk subgroup with a poor
long-term prognosis.
相似文献