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51.
52.
In this study 197 strains of Escherichia coli isolated from cowpats and the faeces of healthy humans were examined for the presence of enterotoxins. Six strains representing five different serotypes were found to be enterotoxigenic. Four of these strains produced the heat labile enterotoxin and two, the Vero cell cytotoxin.  相似文献   
53.
Zusammenfassung Nach Erörterung des pneumoplethysmographischen Meß-prinzips wird seine Anwendbarkeit für Untersuchungen des intraocularen Kreislaufes diskutiert. Das Stromzeitvolumen in den Gefäßen der Netz- und Aderhaut kann durch Kombination der für das Auge zu modifizierenden pneumoplethysmographischen Meßtechnik mit dem Jugulariskompressionsversuch annäherungsweise bestimmt werden.
Possibilities and limits of ocular pneumoplethysmography
Summary The principles of pneumoplethysmography and its application to investigations of the intraocular circulation are discussed. The rate of blood flow through the intraocular vessels may be approximately determined by combining the techniques of pneumoplethysmography and compression of the jugular veins.


Auszugsweise vorgetragen vor der Jahreshauptversammlung der Österreichischen Ophthalmologischen Gesellschaft in Wien, 9. Juni 1969.  相似文献   
54.
Verotoxigenic Escherichia coli (VTEC) are a specialized group of E. coli that can cause severe colonic disease and renal failure. Their pathogenicity derives from virulence factors that enable the bacteria to colonize the colon and deliver extremely powerful toxins known as verotoxins (VT) or Shiga toxins (Stx) to the systemic circulation. The recent devastating E. coli O104:H4 epidemic in Europe has shown how helpless medical professionals are in terms of offering effective therapies. By examining the sources and distribution of these bacteria, and how they cause disease, we will be in a better position to prevent and treat the inevitable future cases of sporadic disease and victims of common source outbreaks. Due to the complexity of pathogenesis, it is likely a multitargeted approach is warranted. Developments in terms of these treatments are discussed.  相似文献   
55.
In this preclinical study we investigated the effect(s) of recombinant human (rh) interleukin 3 (IL-3) on hemopoietic differentiation and attempted to evaluate possible clinical side effects of this hemopoietic growth factor. Rh IL-3, derived from either Escherichia coli or Chinese hamster ovary, was administered subcutaneously to 16 rhesus monkeys (by pairs) at different doses (11, 33, and 100 micrograms/kg/day) for 14 days. During the 2nd week of administration white blood cell counts increased 2- to 3-fold mainly because of a dose-dependent elevation of basophils (up to 40% of white blood cells) and eosinophils. In addition, moderate to marked elevations of plasma histamine levels were measured. Transient diarrhea and an erythematous skin rash with generalized cutaneous lesions that was not restricted to the injection sites were present in 3 of 6 animals treated with E. coli-derived rh IL-3 (1 of 2 animals that received 33 micrograms/kg and 2 of 2 that received 100 micrograms/kg) and 2 of 6 monkeys treated with Chinese hamster ovary-derived rh IL-3 (1 of 2 that received 33 micrograms/kg and 1 of 2 that received 100 micrograms/kg), respectively. Histopathologic and immunohistologic evaluation of skin specimens revealed a perivascular mononuclear cell infiltrate interspersed with numerous mast cells. Signs of vasculitis were absent. The density of the perivascular infiltrate correlated not only with the dose of IL-3 but also with the duration of the skin eruption. Moreover, hyperproliferation of basal keratinocytes resulting in acanthosis was observed in lesions persisting for 1 and 4 days as also evidenced by a significant (p less than 0.01) increase in Ki-67 (a proliferation-associated marker)-positive basal keratinocytes.  相似文献   
56.
During progression of myeloid neoplasms, the basophil compartment may expand substantially and in some of these patients, a basophilic leukemia is diagnosed. In patients with Ph-chromosome+ chronic myeloid leukemia, acceleration of disease is typically accompanied by marked basophilia. In other myeloid neoplasms, secondary leukemic expansion of basophils is rarely seen. We report on 5 patients who suffered from a myelodysplastic syndrome, myeloproliferative neoplasm, or acute leukemia and developed a massive expansion of basophils during disease progression. In 4 of 5 patients, peripheral blood basophil counts reached 40%, and the diagnosis “secondary basophilic leukemia” was established. As assessed by flow cytometry, neoplastic basophils expressed CD9, CD18, CD25, CD33, CD63, PD-L1, CD123, and CLL-1. In addition, basophils were found to display BB1 (basogranulin), 2D7, tryptase and KIT. In 4 of 5 patients the disease progressed quickly and treatment with azacitidine was started. However, azacitidine did not induce major clinical responses, and all patients died from progressive disease within 3 Y. In in vitro experiments, the patients´ cells and the basophilic leukemia cell line KU812 showed variable responses to targeted drugs, including azacitidine, venetoclax, hydroxyurea, and cytarabine. A combination of venetoclax and azacitidine induced cooperative antineoplastic effects in these cells. Together, secondary basophilic leukemia has a poor prognosis and monotherapy with azacitidine is not sufficient to keep the disease under control for longer time-periods. Whether drug combination, such as venetoclax+azacitidine, can induce better outcomes in these patients remains to be determined in future clinical studies.  相似文献   
57.
Fetal MRI is used with increasing frequency as an adjunct to ultrasound (US) in prenatal diagnosis. In this review, we discuss the relative value of both prenatal US and MRI in evaluating fetal and extra-fetal structures for a variety of clinical indications. Advantages and disadvantages of each imaging modality are addressed. In summary, MRI has advantages in demonstrating pathology of the brain, lungs, complex syndromes, and conditions associated with reduction of amniotic fluid. At present, US is the imaging method of choice during the first trimester, and in the diagnosis of cardiovascular abnormalities, as well as for screening. In some conditions, such as late gestational age, increased maternal body mass index, skeletal dysplasia, and metabolic disease, neither imaging method may provide sufficient diagnostic information.  相似文献   
58.
59.
Within normal hemopoiesis, the intranuclear DNA polymerase TdT seems to be exclusively expressed by T and B lymphoid precursor cells. Double staining experiments showed that TdT can also be expressed in blast cells of certain acute myeloid leukemias. Recent reports described a very strong association between TdT expression and rearrangements of IgH and TcR genes in such AML specimens, suggesting a predominant lymphoid commitment of these TdT positive AML blasts. When submitting 24 serologically and morphologically well-characterized TdT positive AML specimens for additional genotypic analysis to determine the IgH and TcR gene configuration, we observed that only four had clonally rearranged IgH and/or TcR genes, whereas 20 had germ line configuration. This frequency is clearly lower than previously reported and not necessarily different from rearrangement frequencies reported for TdT negative AML (4-40%). It would seem to us, therefore, that the expression of TdT in otherwise well-defined AML blasts is not necessarily associated with a higher frequency of immunoglobulin and/or T cell receptor gene rearrangement.  相似文献   
60.
The selectivity of a novel myelomonocytic cell surface antigen, designated M2, has been assessed in a series of 208 leukemias. The M2 antigen is defined by a monoclonal antibody (VIM-2) of the IgM class. Its expression within the normal hemopoietic system is restricted to myelomonocytic cells. Lymphocytes, erythrocytes, thrombocytes and their morphologically recognizable precursors are negative. Sixty of the 66 acute myeloblastic leukemias (= 91%) and 28 of the 30 myeloid blast crises of CML patients (= 93%) were M2-positive. As expected from our findings with normal myeloid cells, the myeloid cells found in stable phase of CML were also in all instances, M2-positive. Quite in contrast, lymphoid cells from patients with B-CLL, T-CLL, prolymphocytic leukemia, hairy-cell leukemia, lymphoblastic lymphoma, Sézary syndrome, from CML patients in lymphoid blast crisis and from the majority of patients with ALL, were completely M2-negative. Also negative were the blast cells of patients with acute megakaryoblastic leukemia and acute erythroleukemia. A direct comparison of M2 expression with the display of the 3-fucosyl-N-acetyllactosamine determinant, the structure recognized by most of the anti-myeloid monoclonal antibodies reported so far, shows that more AMLs are M2-positive and the proportion of M2-positive blast cells in individual AML samples is higher.  相似文献   
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