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2.
M Centola K Lin C Sutton JR Berenson LA Kunkel L Rosen BH Hahn RR Robinson 《Canadian Metallurgical Quarterly》1996,20(5-6):465-469
We have assessed the specificity of antibodies from the leukemic B cells of five patients with both chronic lymphocytic leukemia and autoimmune hemolytic anemia (CLL-AHA). Leukemic cells from one patient displayed surface immunoglobulin with heavy and light chain isotypes identical to that of the patient's anti-red blood cell (RBC) antibodies, and the leukemic cells secreted antibodies in vitro with anti-RBC activity. However, in the remaining patients, the leukemic cells displayed surface immunoglobulin with light chain isotypes different from that of the patient's anti-RBC antibodies and secreted antibodies in vitro with no detectable anti-RBC activity. Thus, there are two distinct classes of CLL-AHA patients, differentiated by the presence or absence of an anti-RBC antibody-producing leukemic B cell clone. The apparent heterogeneity in the source of pathogenic anti-RBC antibodies may impact the treatment response of the two classes of CLL-AHA patients. 相似文献
3.
The microviscosities of the hydrophobic regions of the membranes of intact Semliki forest and Sindbis viruses grown on BHK-21 cells, of liposomes derived from the extracted viral lipids, and of protease-treated virions were measured by fluorescence depolorization using the fluorescence probe 1, 6-diphenyl-1,3,5-hexatriene. The intact virus membranes were found to have a higher microviscosity than did virus-derived liposomes, indicating the viral envelope proteins contribute to microviscosity. However, protease-treated virus, devoid of protruding spikes but with residual lipophilic peptide tails, was found to have a microviscosity more similar to that of the intact virus than to that of protein-free liposomes. Sindbis virus grown in BHK-21 cells at 37 C had a much higher microviscosity than did Sindbis virus grown on Aedes albopicuts cells at 22 C. Sindbis virus grwon in A. albopictus and BHK-21 cells also gave higher microviscosity values than did the intact host cells. These data indicate that both the virion proteins and the cellular lipids selected during viral growth and maturation contribute to the increased microviscosity of togavirus membranes. 相似文献
4.
Seven patients with pulmonary regurgitation (PR), normal pulmonary artery (PA) pressures and large left-to-right atrial shunts are reported. Six had secundum atrial septal defects (ASD) and one had anomalous pulmonary venous drainage. These comprised 4% of 180 patients with atrial shunts and normal PA pressures. Pulmonary regurgitation was diagnosed clinically by mid-frequency diastolic decrescendo murmurs beginning after the pulmonic component of the second heart sound, and diagnoses were confirmed by catheterization. In two patients who had serial preoperative catheterizations over 8 and 16 years, PR progressed in one and was present only on the second study in the other. All patients underwent shunt correction, at which time the pulmonic anulus and artery appeared dilated, but the pulmonic valves were normal and did not require revision. In all patients the PR murmur disappeared after shunt correction alone, and on chest X-ray both PA and overall heart size decreased. Although it is known that pulmonary regurgitation occurs with atrial septal defects and pulmonary hypertension, the present study demonstrates that it also occurs with high flow atrial shunts, in which setting it has different implications and is reversible with shunt correction alone. 相似文献
5.
Tryptophan metabolism was studied in a family in which a sister and brother had bladder cancer. Urinary tryptophan metabolites after administration of 2 g L-tryptophan were measured in 4 sisters and 1 brother, all free of disease when studied. One sister with and 2 without histories of bladder cancer had significantly elevated levels of kynurenine, acetylkynurenine, and 3-hydroxykynurenine. Administration of 100 mg pyridoxine hydrochloride returned the tryptophan metabolism to normal in these 3 individuals. One brother with a 1 sister without bladder cancer had normal metabolism. A repeat study 2 years later confirmed the abnormal metabolism in the 3 sisters. Two sisters with abnormal tryptophan metabolism were given 200 mg L-kynurenine sulfate orally to bypass the effects of tryptophan oxygenase activity. Both excreted elevated levels of kynurenine and 1 excreted elevated levels of 3-hydroxykynurenine. 相似文献
6.
Adult miniature swine were exposed to various levels and durations of +Gz. After exposure, all swine were euthanized and necropsied. Gross, histologic, and electronmicroscopic observations were made on the heart tissue. Subendocaridal hemorrhage (SEH) was commonly found in the left ventricle, rarely in the right ventricle, and its severity was directly related to : a) level and duration of G exposure, b) heart rate, and c) catecholamine activity. SEH was made more severe with i.v. atropine 4 mg, and prevented with i.v. propranolol 20 mg. Heart hemorrhage was usually limited to the immediate subendocardial region and frequently surrounded Purkinje's fibers. In severe cases, however, hemorrhages penetrated several millimeters into the heart muscle and sometimes penetrated Purkinje's fibers. Restraint of unanesthetized swine in the centrifuge couch, low G-levels, and/or i.v. injections of atropine or epinephrine produced minimal SEH lesions. 相似文献
7.
M Dempsey DL Dunner RR Fieve T Farkas J Wong 《Canadian Metallurgical Quarterly》1976,133(9):1082-1084
Six female primary affective disorder patients who had gained an average of 9.5 kg while taking lithium lost an average of 2.9 kg on a 10-day 900 calorie a day hospital diet containing 100 mEq of sodium per day. No evidence of lithium toxicity was observed on this regimen. There was no evidence that fluid retention played a major role in the weight gain. 相似文献
8.
The described equivalence postulate was confirmed experimentally by examining physiological responses as well as discomfort sensation in a series of predicted equivalent conditions during exercise (congruent to 3 met). ET or the equivalent Ta at 50% RH is a single independent variable that is uniquely related to the mean skin temperature (Tsk), skin wettedness (w), body core temperature (Tcore) and sense of discomfort. 相似文献
9.
W De Souza MA Rossi EW Kitajima RR Santos I Roitman 《Canadian Metallurgical Quarterly》1976,22(2):197-203
The fine structure of the promastigotes of Herpetomonas sp. (Leptomonas pessoai) kept in a defined medium at 28 degrees C is described. This portozoon reveals several features in common with other trypanosomatids. A membrane-bounded organelle measuring 0.2 to 0.8 mum in diameter, similar to that described as peroxisome in Crithidia fasciculata, was also observed. A large cavity, located between the nucleus and the kinetoplast and containing vesicles and small particulate material is discussed in this paper. 相似文献
10.
In 1991 a new reform for postgraduate trainees was introduced in Denmark. Since the reform all young doctors-as a compulsory part of their vocational training-have had to work for six months as general practice trainees, no matter their wishes for future specialization. The reform furthermore led to the general practice trainees being considerably younger than previously-the average length of postgraduate experience before working as a trainee declined from six to seven years to one to two years. In this light an investigation was conducted from August 1992 to July 1993. Seven hundred and fifty-eight questionnaires were sent to general practice trainees and their tutors in Denmark. Ninety-five percent of the questionnaires were returned, thus it was possible to evaluate the new compulsory training in general practice. In conclusion, the main part of the trainees had a positive assessment of the work conditions in general practice. However, a large part of the trainees indicated that their tutor doctors had set aside too short a time for supervision. 相似文献