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331.
Bartram  CR; Raghavachar  A; Anger  B; Stain  C; Bettelheim  P 《Blood》1987,69(6):1682-1685
To study the possible involvement of T lymphocytes in Philadelphia chromosome (Ph)-positive chronic myelocytic leukemia (CML) we analyzed the arrangement of the bcr gene in T cell and non-T cell samples of 12 CML patients. Although all the patients showed bcr rearrangements in non-T cell fractions, T cell populations lacked respective gene recombinations. Moreover, by Southern blot analyses using T cell receptor beta chain sequences our data indicate polyclonality of T cell samples from 11 of 12 cases; in one patient a clonal T cell population could be identified. These results suggest that T lineages of most Ph- positive CML patients are not derived from pluripotent stem cells involved in leukemogenesis and thus confirm previous investigations based on cytogenetic or glucose-6-phosphate dehydrogenase analyses. The demonstration of polyclonal T cell populations may reflect persistence of stem cells committed to differentiate only into T cells.  相似文献   
332.
Summary In order to determine the frequency of hepatosplenic abscesses in AML patients during chemotherapy and to evaluate the clinical and laboratory characteristics of this complication we performed a prospective study over a 28-month period. Fifty-five consecutive patients with de novo AML or relapse who received intensive chemotherapy underwent regular ultrasound examinations. In 16 patients (29.1%) hepatic and/or splenic abscesses were detected sonographically. Histopathological evidence for abscess formation was obtained in five of these 16 patients. In three patients granulation tissue and in one patient necrotizing granulomas were found. Causative micro-organisms were proven in only three patients:Candida hyphae were demonstrated in one patient, gram-positive cocci in another. Bacteria and fungi were seen in the tissue specimen of the third patient. Patients with hepatosplenic abscesses had significantly prolonged fever after neutrophil recovery but did not differ from patients without abscesses in any other laboratory or clinical features. Due to the absence of specific alerting clinical and laboratory signs and symptoms of hepatosplenic abscesses, routine ultrasound examination is required for detection of this complication. The presence of hepatic and/or splenic abscesses does not necessarily worsen the prognosis, but it may influence the decision on further chemotherapy and antimicrobial treatment.  相似文献   
333.
We present a female patient with a B-immunoblastic lymphoma of the IgM-lambda type arising in angioimmunoblastic lymphadenopathy. An increased ratio of helper/inducer to suppressor/cytotoxic lymphocytes in the lymph node could have triggered the proliferation of B cells. Evolution of IgM cryoglobulinemia was paralleled by malignant transformation in the lymph node. A short-term in vitro chemosensitivity test could predict response to COP combination chemotherapy suggesting that in vitro chemosensitivity testing can be useful for the therapeutic management of angioimmunoblastic lymphadenopathy.  相似文献   
334.
Summary The sources from which eight Caesarean section babies acquiredE. coli are described and the probable routes by which the organisms reached the babies are outlined. Suggestions are made concerning the control of the spread ofE. coli in premature nurseries and during outbreaks ofE. coli gastroenteritis.
Escherichia coli bei kaiserschnitt-entbundenen Kindern und deren Umgebung
Zusammenfassung Der Ursprung vonE. coli Stämmen, die von Kindern nach einer Sectio isoliert werden konnten, und der wahrscheinliche Weg zu den Neugeborenen werden aufgezeigt. Es werden Vorschläge gemacht, um die Ausbreitung vonE. coli in Frühgeborenenstationen und bei Ausbrüchen vonE. coli-Gastroenteritiden unter Kontrolle zu bringen.
  相似文献   
335.
Circulating granulocyte/macrophage progenitor cells (CFU-GM) were assayed serially during remission in 17 patients with acute leukaemia (9 ALL, 8 AML). In patients with ALL receiving cyclophosphamide, 6-mercaptopurine and methotrexate, CFU-GM numbers were significantly lower than in normal individuals; cycles of 'reinduction' chemotherapy (vincristine, prednisolone) caused a 10-fold increase in CFU-GM per ml of blood. In 2 ALL patients a substantial increase in CFU-GM numbers preceded the morphologically detectable relapse. In patients with AML receiving repeated courses of cytosine-arabinoside and 6-mercaptopurine, circulating CFU-GM were likewise reduced. In 6 patients who relapsed, a further reduction of CFU-GM was seen. A complete absence of circulating CFU-GM was observed in 10 of the 23 investigations performed within 6 weeks prior to the morphologically detectable relapse, while such a 'zero'-growth occurred in only 1 of 54 experiments performed during stable remission. In summary, in patients with ALL in remission, circulating CFU-GM are increased following treatment with vincristine and prednisolone. In patients with AML, declining numbers of circulating CFU-GM may predict an imminent relapse.  相似文献   
336.
This is the first comprehensive serological analysis of a haemolytic uraemic syndrome (HUS) outbreak. A wide range of 'O' group Escherichia coli antibody responses in patients and controls was examined. The study provides a unique insight into the epidemiology of such epidemics, points a way to the most appropriate investigation of these and indicates possible answers to a number of issues related to severity of disease. In order to be able to test for a wide variety of E. coli 'O' antigens, a microagglutination assay was used to examine E. coli 'O' group serological responses of 22 children admitted to hospital with HUS and 14 contemporaneous age-matched controls. A total of 51 'O' serogroup strains were used. These included 'O' groups reported to be associated with cases of HUS, with 6 isolates from patients associated with the Adelaide outbreak (O26, O111, O123 and O157), environmental Verocytotoxigenic/Shiga-toxin producing Escherichia coli (VTEC/STEC) strains and common human commensal strains. Sixteen clinically confirmed HUS cases (72.7%) of 22 seroconverted to 1 or more serogroups of which 11 (50%) seroconverted to O111 (the serogroup isolated from 16 patients). In addition, 11 (50%) and 10 (45.5%) developed antibody to O137 and O145, respectively, although no stool isolates of these serogroups were made. Seventeen (77.3%) of 22 HUS patients had antibody to serogroup O157, with 11 (50%) seroconversions, however, O157:H- was isolated from only 2 of these. Overall, titres ranged from 100 to 6400, some of the highest in 3 patients were against O157, whose faeces yielded only Enterohaemorrhagic E. coli (EHEC) O111, and only 1 developed O111 antibody. Mixed infection was demonstrated serologically by microagglutination (confirmed by Western blot) and was consistent with the findings of multiple serogroups of VTEC found in the mettwurst incriminated as the source, and suggests further strains (not found in the source or in patients' faeces) were probably also involved. In HUS associated with EHEC infection, multiple strain infection may be the rule rather than the exception. A relationship with clinical severity deserves further investigation. Non-O157 EHEC (in addition to O157) should be sought in all future outbreaks of EHEC disease.  相似文献   
337.
The in vivo effect of recombinant human interleukin-3 (rhIL-3) on peripheral blood (PB) levels of hematopoietic progenitor cells was studied in nonhuman primates. Subcutaneous administration of 33 micrograms/kg/d of rhIL-3 for 11 to 14 days to rhesus monkeys slightly raised leukocyte counts (twofold) and substantially expanded the pool of circulating stem cells in the second week of treatment. At the end of rhIL-3 administration, PB levels of granulocyte/macrophage colony-forming units (CFU-GM) increased by a mean of 12-fold; burst-forming units-erythroid (BFU-E) by ninefold; CFU-mix, by 12-fold; and CFU-megakaryocyte (Mk), by 13-fold as compared with their respective pretreatment values. Subsequent administration of recombinant human granulocyte/macrophage colony-stimulating factor (rhGM-CSF; 5.5 micrograms/kg/d for 5 days) to rhIL-3-pretreated animals further expanded the PB stem cell compartment leading to maximum levels of CFU-GM that were in average much more increased (63-fold) than CFU-GM levels under rhIL-3 (14-fold) or rhGM-CSF (12-fold) alone. This hitherto unknown effect of rhIL-3 on the pool of circulating progenitors, particularly in synergy with rhGM-CSF, may facilitate harvest of hematopoietic progenitor cells from PB for stem cell transplantation.  相似文献   
338.

Objective

Situs anomalies refer to an abnormal organ arrangement, which may be associated with severe errors of development. Due regard being given to prenatal magnetic resonance imaging (MRI) as an adjunct to ultrasonography (US), this study sought to demonstrate the in utero visualization of situs anomalies on MRI, compared to US.

Materials and methods

This retrospective study included 12 fetuses with situs anomalies depicted on fetal MRI using prenatal US as a comparison modality. With an MRI standard protocol, the whole fetus was assessed for anomalies, with regard to the position and morphology of the following structures: heart; venous drainage and aorta; stomach and intestines; liver and gallbladder; and the presence and number of spleens.

Results

Situs inversus totalis was found in 3/12 fetuses; situs inversus with levocardia in 1/12 fetuses; situs inversus abdominis in 2/12 fetuses; situs ambiguous with polysplenia in 3/12 fetuses, and with asplenia in 2/12 fetuses; and isolated dextrocardia in 1/12 fetuses. Congenital heart defects (CHDs), vascular anomalies, and intestinal malrotations were the most frequent associated malformations. In 5/12 cases, the US and MRI diagnoses were concordant. Compared to US, in 7/12 cases, additional MRI findings specified the situs anomaly, but CHDs were only partially visualized in six cases.

Conclusions

Our initial MRI results demonstrate the visualization of situs anomalies and associated malformations in utero, which may provide important information for perinatal management. Using a standard protocol, MRI may identify additional findings, compared to US, which confirm and specify the situs anomaly, but, with limited MRI visualization of fetal CHDs.  相似文献   
339.
A 43 year-old female patient was admitted on account of severe dyspnoea of several months' duration and thrombocytopenia. The clinical symptomatology was compatible with pulmonary embolism, but no source of embolization was found and heparin therapy did not lead to clinical improvement. Angiography of the pulmonary artery revealed multiple filling defects. Symptoms improved after treatment with cortisone and so a malignant process was assumed. The patient died from right ventricular failure before the diagnosis could be established. At autopsy a sarcoma of the pulmonary artery, obviously originating from the pulmonary trunk was found. Thrombocytopenia most probably resulted from consumption of platelets by a mechanism corresponding to the Kasabach-Merritt syndrome. The difficulties in the diagnosis of pulmonary artery sarcomas are discussed and the 69 previously published cases are reviewed.  相似文献   
340.
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