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101.
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Spleen cells from normal (C57BL/6 X DBA/2)F1 mice were sensitized in vitro for 5 days with irradiated C57BL/6 or DBA/2 parental stimulating cells. Effector cells were generated which specifically lysed 51Cr-labeled targets (leukemia or mitogen-stimulated lymphoid cells) H-2-matched with the parental genotype used for sensitization. The response of F1 spleen cells to the C57BL/6 parent was stronger and more reproducible than that to the DBA/2 parent. The kinetics of generation of effector cells were similar for the F1 anti-parent and an F1 anti-allogeneic response. However, the magnitude of the F1 anti-C57BL/6 cytotoxic response was considerably lower than the F1 response to allogeneic cells. The ratio of responder to stimulator cells in the cultures was more critical for the former than for the latter response. Several lots of fetal bovine serum were found to be adequate for supplementing the medium in the induction of J1 hybrid anti-parent and anti-allogeneic cytotoxic effector cells. Based on these and other studies, it would appear that the F1 hybrid anti-parent cytotoxic response provides an in vitro model of murine hemopoietic graft rejection in vivo. This response may be elicited by a mechanism distinct from T cell-mediated cytotoxicity and involve different subpopulations of spleen cells. 相似文献
103.
In unasthetized dogs naloxone induced effects opposed to those of morphine (tachycardia, agitation, hyperthermia, tachypnea) and mydriasis. These effects were moderate and transient; some of them were elicited with low doses being border-line after 0.03 mg.kg-1 s.c., statistically significant after 0.1 mg.kg-1 s.c.; they increased slightly with the dose. After repeated administrations, acute tolerance developed and some moderate morphine-like effects (miosis, sedation) were observed. The stimulatory effects described here may result from antagonism of a morphinomimetic natural ligand,and represent thus indirect arguments in favour of normal functions of this ligand; these functions would be to temper not only algesic but also other stimulant reactions. The limitation of the effects might result from the limited release of this ligand in normal dogs and (or) from interfering morphinomimetic properties of naloxone, which are apparently unmasked when administrations are repeated. Both, stimulatory and inhibitory effects of naloxone are not liable to represent noticeable side-effects of this drug, but they both might play some role in the mechanisms of precipitated abstinence. 相似文献
104.
Thirteen schizophrenic patients who developed abnormal psychotic behavior as an adverse reaction to a neuroleptic are described. A. Three patients showed a marked increase in the psychopathology during neuroleptic treatment. These episodes were treated by decreasing or discontinuing the neuroleptics. They did not respond to anticholinergic durgs nor did they respond to an increase in dosage, (another side effect previously reported and referred to here) indeed this treatment worsened the situation. B. Ten patients showed a mixed picture of catatonic excitement or inhibition on neuroleptics and several developed hallucinatory episodes. All of these exacerbations were terminated by anticholinergic injections. Other more familiar CNS abnormalities produced by neuroleptics are briefly discussed. 相似文献
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1. Methods are described for the morphometric estimation of parameters of the gill system of trout which are relevant to its function in gas exchange. The methods have been used with 1 mum sections viewed under the light microscope. 2. In particular the diffusion distances between water and blood are measured, which together with determinations of gill area, provide figures for the morphometrically estimated diffusing capacity. 3. The methods have been used to compare the diffusing capacity of gills from control fish and those treated in polluted waters. The concept of relative diffusing capacity (Drel) is introduced which enables comparisons to be made without the need to determine the absolute diffusing capacity. 4. Quantitative estimation of changes in relative volumes and surface areas of components of the secondary lamellae were determined, and employed to explain the possible anatomical causes of changes in Drel. 5. It is suggested that these methods can be of value in the comparison of the gills of fish treated in different waters. 相似文献
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GM Khalil 《Canadian Metallurgical Quarterly》1976,40(2):232-237
The anthelmintic efficacy of fenbendazole (methyl 5-(phenylthio)-2-benzimidazole carbamate) was tested in sheep against standardised strains of Hcaemonchus contortus and Trichostrongylus colubriformis, known to be resistant to thiabendazole (LD90 for thiabendazole against H ontortus was 200 mg/kg bodyweight and against T colubriformis was 150 mg/kg). Fenbendazole at dose rates of 5, 10 and 20 mg/kg per os reduced total worm counts in H contortus infected sheep by 66, 90 and 100 per cent respectively, with similar reductions recorded for worm egg outputs. For the thiabendazole resistant strain of T colubriformis, fenbendazole reduced total worm counts in infected sheep by 4, 44 (40-48), 79 (75-83), 96 and 100 per cent at dose rates of 5, 10, 20, 40 and 80 mg/kg per os. Significant suppression of worm-egg production by thiabendazole resistant T colubriformis was obtained with fenbendazole at dose levels of 5 mg/kg and above. The implications of these results are discussed in the light of the increasing occurrence of strains of trichostrongylid nematodes resistant to currently available benzimidazole anthelmintics. 相似文献
109.
D Zagzag DC Miller GM Kleinman A Abati H Donnenfeld GN Budzilovich 《Canadian Metallurgical Quarterly》1993,17(6):537-545
Clinical presentations as well as radiological and histopathological findings in biopsies from patients with multiple sclerosis (MS) or other demyelinating disorders of the central nervous system are sometimes misleading, resulting in an erroneous diagnosis of brain or spinal cord tumor. We report 17 patients who presented with symptoms mimicking those of brain (14 cases) or spinal cord (three cases) tumors. Computerized tomography or magnetic resonance imaging studies or both were interpreted as consistent with a tumor in each case. All patients underwent surgery, and all 17 pathological specimens were eventually diagnosed as showing demyelinating disease, usually consistent with MS. In each case we examined a variety of histological features and immunohistochemical studies and addressed their relative importance in considering the diagnosis of MS. All cases showed perivascular lymphocytic inflammation with variable amounts of macrophage infiltration, necrosis, and edema. The hypercellularity of the lesions and the presence of atypical reactive astrocytes with mitotic figures were the disturbing features that might have led to the erroneous diagnosis of an astrocytic neoplasm. Immunohistochemistry for astrocytic (glial fibrillary acidic protein) and macrophage (HAM-56) markers are helpful in evaluating biopsies. Our results emphasize the need to perform special stains (i.e., for myelin and axons) that demonstrate myelin loss and relative preservation of axons and allow a correct diagnosis. 相似文献
110.