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111.
Summary Helix pomatia ganglion cells have voltage clamp currents which are similar to those of the squid axon if short voltage clamp pulses are applied and resting membrane voltages are below 60 mV.If voltage pulses are prolonged, there is a progressive decay of the late outward current which does not follow first order kinetics. With higher resting and holding potentials an additional subthreshold current component appears which probably is part of a pacemaker mechanism. 相似文献
112.
The Enhancing Effect of Spawning on Elimination of a Persistent Polychlorinated Biphenyl from Female Yellow Perch 总被引:3,自引:1,他引:2
The Enhancing Effect of Spawning on Elimination of a PersistentPolychlorinated Biphenyl from Female Yellow Perch. VODICNIK,M. J., AND PETERSON, R. E. (1985). Fundam. Appl. Toxicol. 5,770776. Distribution and elimination of 2,5,2',5'-tetrachloro[14C]biphenyl.(4-CB) were studied for 6 months after exposing sexually maturefemale yellow perch to the compound in water and transferringthem to flowing 4-CB-free water. Perch that were exposed inJanuary spawned in May, and the study was terminated in June.During the first 4 months after exposure, the t for whole-bodyelimination was 22 weeks, primarily by elimination of 4-CB fromthe viscera and carcass. During spawning, enhanced elimination(t < 0.7 weeks) was due to the voiding of eggs containing4-CB. After spawning, whole-body elimination returned to a slowerrate (t = 16.3 weeks). Prior to the enhancement in 4-CB eliminationrate during spawning, there was a redistribution of 4-CB residueswithin the body of the perch which was characterized by a transferof 4-CB residues from primarily the carcass and viscera to eggs.Two weeks after exposure, 30% of the initial 4-CB body burdenwas distributed to the eggs, whereas just prior to spawning,about 50% was present in this tissue. These findings demonstratethat egg maturation and spawning result in a significant reductionin the body burden of a persistent polychlorinated biphenylin a lean-fish species. 相似文献
113.
The changes in the percentage of serum proteins and erythrocyte sedimentation rates in 14 swine given weekly injections of Erysipelothrix insidiosa or other antigens were studied. A sharp rise in the erythrocyte sedimentation rate and in the percentage of alpha globulin occurred at the seventh day after the first injection in seven of the eight pigs which received the viable cultures. The erythrocyte sedimentation rate and percentage of alpha globulin then returned to normal. Later, as arthritis developed, the erythrocyte sedimentation rate again increased, but this time the increased rate was accompanied by an increase in the percentage of gamma globulin.The erythrocyte sedimentation rate and percentage of serum proteins remained virtually unchanged in the three animals which were given dead erysipelas organisms and in the three animals which were given culture medium alone. 相似文献
114.
115.
ObjectiveTo determine the prevalence of asymptomatic bacteriuria in pregnancy, to consider the antimicrobial sensitivity patterns of involved uropathogens, to elucidate the safety profiles of antibacterial agents, and to evaluate the role of urinalysis in screening for asymptomatic bacteriuria.MethodsAbout 760 apparently healthy pregnant subjects attending the Antenatal Clinic of the University of Port Harcourt Teaching Hospital were randomly selected for this study. Urinalysis and microscopy, culture, and sensitivity tests were carried out on clean-catch midstream urine samples obtained from subjects. Biochemical reagent strips were used for urinalysis while the standard wire loop and agar diffusion technique were respectively employed for culture and susceptibility testing.ResultsA total of 111 samples yielded moderate or severe growth on culture after 48 hours comprising 35, 31, 27, and 18 isolates of Staphylococcus spp., Proteus spp., Klebsiella spp., and Escherichia spp, respectivehy. Urinalysis results were positive for the presence of nitrate reductase and leucocyte esterase activity in 17 urine samples of these 111 samples. The isolates showed a general sensitivity to the fluorinated quinolones and to Nitrofurantoin.ConclusionsThe prevalence of asymptomatic bacteriuria is 14.6%, with the predominant organism being Staphylococcus spp. Drugs used for treatment should have excellent fetal safety profiles, and a rapid screening test with a high negative predictive value for asymptomatic bacteriuria would be ideal. 相似文献
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118.
High-dose therapy and autologous peripheral blood stem cell transplantation for patients with lymphoma 总被引:3,自引:0,他引:3
Kessinger A; Armitage JO; Smith DM; Landmark JD; Bierman PJ; Weisenburger DD 《Blood》1989,74(4):1260-1265
Forty patients with refractory Hodgkin's disease (24 patients) or non- Hodgkin's lymphoma (16 patients) who were considered for high-dose therapy but not for autologous bone marrow transplantation (ABMT) due to BM metastases, previous pelvic irradiation, a history of marrow involvement by tumor or hypocellular marrow in conventional harvest sites received high-dose therapy and autologous peripheral blood (PB) hematopoietic stem cell transplantation. Disappearance of circulating neutrophils and development of RBC and platelet transfusion-dependence was followed, in the evaluable patients, by reappearance of 0.5 x 10(9)/L circulating granulocytes and sufficient platelets to obviate the need for platelet transfusions at a median of 25 days after transplantation. Twenty-three patients experienced a clinical complete remission (CR). The projected 2-year event-free survival was 24% for all 40 patients and 49% for the non-Hodgkin's lymphoma patients. The projected 18-month event-free survival for the Hodgkin's disease patients was 15%. PB stem cell transplantation provided an opportunity to administer high-dose salvage therapy to patients with refractory lymphoma who otherwise were not candidates for such therapy. For some of those patients, the high-dose therapy produced prolonged survival, free of tumor progression. 相似文献
119.
Autologous peripheral hematopoietic stem cell transplantation restores hematopoietic function following marrow ablative therapy 总被引:2,自引:0,他引:2
From ten patients with advanced malignant disease involving the bone marrow, autologous hematopoietic stem cells were collected from the peripheral blood during eight four-hour pheresis procedures and cryopreserved. No manipulations to increase the number of stem cells circulating in the blood were used during the collections. Following marrow ablative chemotherapy or chemoradiotherapy, the autologous cells were thawed and infused intravenously (IV). WBCs reappeared in the circulation at a median of eight days (range seven to 11 days) after stem cell infusion. Two patients died early, whereas the other eight reached normal numbers of circulating granulocytes that have persisted for up to greater than 20 months. These eight patients became independent of RBC transfusions (hemoglobin concentration greater than 10 g/dL) at a median of 27 days (range 11 to 58 days) after transplantation. One patient received platelet transfusions for counts less than 50 x 109)/L, one patient developed a clinical picture of idiopathic thrombocytopenic purpura, and six patients maintained a platelet count greater than 20 x 10(9)/L at a median of 23 days (range 14 to 25 days) following stem cell infusion. This technique allows patients ineligible for autologous bone marrow transplantation due to unacceptable anesthetic risks, prior pelvic irradiation, or bone marrow metastases to receive marrow ablative therapy. 相似文献
120.
In vitro autoradiographic and in vivo scintigraphic localization of somatostatin receptors in human lymphatic tissue 总被引:6,自引:0,他引:6
Reubi JC; Waser B; Horisberger U; Krenning E; Lamberts SW; Gebbers JO; Gersbach P; Laissue JA 《Blood》1993,82(7):2143-2151
Receptors for the neuropeptide somatostatin (SS) were evaluated in vitro and in vivo in various human lymphatic tissues, ie, thymus, spleen, and lymph nodes; thymic carcinoids and thymomas were also tested. The receptors were measured in vitro using receptor autoradiography on tissue sections incubated with the SS analog 125I- [Tyr3]-octreotide or 125I-[Leu8,D-Trp22,Tyr25]-SS-28. All tissues were SS-receptor positive for either radioligand, except the thymomas. In thymic tissue, the receptors were diffusely located in the medulla, presumably on epithelial cells. In the spleen, the red pulp was strongly labeled. In the lymph nodes, the germinal centers were preferentially labeled. In all tissues, the receptors were of high affinity (kd thymus, 0.84 nmol/L; kd spleen, 1.6 nmol/L; kd lymph node, 0.62 nmol/L) and specific for SS. Displacement by nanomolar concentrations of SS-14, SS-28, and octreotide was observed, as was guanosine triphosphate dependency. The in vivo visualization of somatostatin receptors was performed after injection of 111In-DTPA- octreotide and gamma-camera scintigraphy. The spleen, but not thymus or lymph nodes, were visualized. These data suggest an important role for SS in regulating immune functions through SS receptors in thymus, spleen, and lymph nodes. Furthermore, SS may regulate neuroendocrine functions in the thymus. 相似文献