In order to obtain the serotype distribution of E.coli from duck and to screen the vaccine bacterial strains,the serotype identifications and biological characteristics of E.coli were analyzed in recent years from Shandong,Hebei and other areas of commercial duck field;selections of vaccine strains were detected by the virulence and immunogenicity.Totally 44 isolated bacterial strains of E.coli from duck were identified to a total of six serotypes:O78,O93,O76,O2,O92 and O32.The O78 serotype was the dominant serotype,accounting for 56.8％ (25/44);O93 serotype for 15.9％ (7/44) according to bacterial Oantigen typing.The strain SD (O78 serotype) was confirmed to have strong virulence and good immunogenicity.The O78,O93 and O76 are the dominant serotypes of duck E.coli in the study areas.The SD strain could be used as the candidate for the next development of inactivated vaccine.

OBJECTIVETo learn more about the clinical and laboratory features of patients with paroxysmal nocturnal hemoglobinuria (PNH) diagnosed in the past ten years.

METHODSClinical and laboratory data for 78 cases of PNH diagnosed from January 1990 to November 1999 in our hospital were analyzed retrospectively.

RESULTSIn comparison with PNH cases reported in the 1980s, the newly diagnosed PNH cases showed the following features: (1) older age of disease onset (from 27 to 34 years); more female cases (from 18.5% to 38.5%); more cases without hemoglobinuria (from 24.2% to 38.5%). (2) No positive family hereditary history. (3) Bone marrow dysplasia, abnormal karyotype and negative sister chromatid differentiation were found in 19.2%, 12.2% and 8.9% of the PNH patients, respectively. 12.3% of the patients had bone marrow hypoplasia, and most of them had no hemoglobinuria. Ham's tests were negative in about 34.2% of the cases. CD55 and CD59 on peripheral blood cells were deficient in 100.0% of the cases, suggesting that CD55 and CD59 tests can improve the diagnosis of PNH. (4) Adrenocortical hormone was effective in 83.8% of the patients, 54.2% of whom relapsed within one year. Eight refractory and relapsed patients were treated with low dose chemotherapy (MP therapy: Melphalan 2 - 6 mg x d(-1); Prednisone 0.5 mg x kg(-1) x d(-1)). Five (62.5%) of them showed positive responses. Bone marrow failure and other side effects were not serious in this group of patients.

CONCLUSIONSPNH, an acquired blood disease seen more often among adult males, can be diagnosed more sensitively by hemocyte member CD55 and CD59 tests and treated more effectively with adrenocortical hormone or low dose chemotherapy.

Adolescent ; Adult ; Aged ; Child ; Female ; Hemoglobinuria, Paroxysmal ; diagnosis ; physiopathology ; Humans ; Male ; Middle Aged ; Retrospective Studies

OBJECTIVETo evaluate the long-term outcome of immunosuppressive therapy (IST) in patients with severe aplastic anemia (SAA).

METHODSHematopoietic recovery (peripheral blood cell counts, bone marrow aspirates, bone marrow biopsy, in vitro culture of hematopoietic progenitors), immunity of T lymphocyte, quality of life and side-effects of the therapy were assessed in 50 SAA patients who have survived more than 3 years after IST.

RESULTSAt 3 years, 4 years and 5 years follow-up, 81.5% (13 cases), 86.7% (13 cases) and 89.5% (17 cases) of the SAA patients reached and maintained normal peripheral blood cell counts, 93.4% (15 cases), 93.3% (14 cases) and 94.7% (18 cases) showed normal bone marrow pictures, and 37.5% (6 cases), 40.0% (6 cases) and 73.7% (14 cases) had normal yields of bone marrow cell culture, respectively. Overall, 86.0% (43 cases), 94.0% (47 cases) and 52.0% (26 cases) of the total SAA patients were normalized in peripheral blood counts, bone marrow picture and culture of hematopoietic progenitor yields, respectively. During the follow-up, 88.0% (44 cases) of the patients achieved 100 of Karnofsky scores; 26 of the 31 patients (83.9%) who received bone marrow biopsy showed normal histological pictures, and 29 of 37 patients (78.4%) tested had normal subsets of T lymphocytes. No clonal disease was found. The late side-effects of IST were mild. All of the parameters tested were normal in 24 patients.

CONCLUSIONAfter IST, the hematopoietic function of bone marrow, the immunity of the T lymphocyte and the life quality were normalized with few side-effects in patients with SAA. These patients would probably be cured.

Adolescent ; Adult ; Anemia, Aplastic ; drug therapy ; mortality ; Blood Cell Count ; Bone Marrow Examination ; Child ; Disease-Free Survival ; Female ; Follow-Up Studies ; Hematopoietic Stem Cells ; cytology ; physiology ; Humans ; Immunosuppressive Agents ; therapeutic use ; Karnofsky Performance Status ; standards ; Male ; Middle Aged ; Recovery of Function ; physiology ; Survival Rate ; Treatment Outcome

OBJECTIVETo explore prospective diagnostic criteria for preleukemia.

METHODSA case control study was done comparing the discrepancies on clinical and laboratory features between patients with preleukemia and those with chronic aplastic anemia (CAA) or atypical paroxysmal nocturnal hemoglubinuria (a-PNH).

RESULTSThere were eight variables of significance: (1) lymphocytoid micromegakaryocytes in the bone marrow; (2) immature granulocytes in the peripheral blood; (3) > or = 2.0% myeloblasts in the bone marrow; (4) positive periodic acid schiff (PAS) stained nucleated erythrocytes; (5) myeloid differentiation index > or = 1.8; (6) typical colonal karyotypic abnormalities; (7) negative sister chromatid differentiation; (8) cluster/colony ratio of granulocyte-macrophage colony-forming units (CFU-GM) > 4.0. The following criteria were assigned: A: to meet variable one and at least two of the other seven variables and B: to meet at least four of the eight variables. All of the patients with preleukemia met either A or B and none of the patients with CAA or a-PNH did.

CONCLUSIONSPreleukemia is different from CAA or a-PNH. It has its own clinical and laboratory features, which may be useful for its prospective diagnosis.

Adolescent ; Adult ; Aged ; Apoptosis ; Case-Control Studies ; Chromosome Aberrations ; Female ; Humans ; Immunophenotyping ; Male ; Middle Aged ; Preleukemia ; diagnosis ; genetics ; pathology ; Survival Rate