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1.
2.
Synopsis A sensitive method is presented for measurement of changes in the permeability of mitchondria in cultured cells. Rat heart endothelioid cells were used to determine the penetration rate of nitroblue tetrazolium (NitroBT) or other reactants into mitochondriain situ. Nitroblue formazan, produced as a consequence of succinate dehydrogenase activity in the mitochondria, was eluted and measured with a spectrophotometer. Prior injury of cells with hypo-osmolar solutions increased the rate of formazan production. Several methods are described or suggested for the statistical analysis of the data. 相似文献
3.
Trypsin-releasable glycosaminoglycans from the luminal surface of intact pig aorta were measured following metabolic labelling with35S]sulphate. Chondroitin sulphate was found to be present at a surface density equal to that already established for heparan sulphate (5×1011 chains per cm2). This result was confirmed by X-ray microanalysis of the luminal sulphur content before and after treatment with specific glycosaminoglycan-degrading enzymes. This result implies that approximately half of the luminal surface is occupied by sulphated glycosaminoglycans. 相似文献
4.
Phylogenetic distribution in the genus Mus of t-complex-specific DNA and protein markers: inferences on the origin of t-haplotypes 总被引:8,自引:0,他引:8
Delarbre C; Kashi Y; Boursot P; Beckmann JS; Kourilsky P; Bonhomme F; Gachelin G 《Molecular biology and evolution》1988,5(2):120-133
We have examined the phylogenetic distribution of two t-specific markers
among representatives of various taxa belonging to the genus Mus. The
centromeric TCP-1a marker (a testicular protein variant specific for all
t-haplotypes so far studied) has also been apparently detected in several
non-t representatives of the Mus IVA, Mus IVB, and probably M. cervicolor
species. By contrast, a t-specific restriction- fragment-length
polymorphism allele (RFLP) of the telomeric alpha- globin pseudogene DNA
marker alpha-psi-4 was found only in animals belonging to the M.
musculus-complex species either bearing genuine t- haplotypes or, like the
M. m. bactrianus specimen studied here, likely to do so. This t-specific
alpha-psi-4 RFLP allele was found to be as divergent from the RFLP alleles
of the latter, non-t, taxonomical groups as it is from Mus 4A, Mus 4B, or
M. spretus ones. These results suggest the presence of t-haplotypes and of
t-specific markers in populations other than those belonging to the M. m.
domesticus and M. m. musculus subspecies, implying a possible origin for
t-haplotypes prior to the radiation of the most recent offshoot of the Mus
genus (i.e., the spretus/domesticus divergence), some 1-3 Myr ago.
相似文献
5.
After total-body exposure to various doses of ionizing radiation, the ability of lymphocytes to interact specifically with high endothelial venules of rat cervical and mesenteric lymph nodes was analyzed in frozen sections. Following a radiation dose of 1.5 Gy, high endothelial venules remained intact and the binding of unirradiated lymphocytes to the venules was enhanced relative to unirradiated controls. At radiation doses above 5.0 Gy, damage to high endothelial venules was observed histologically as well as assessed functionally. There was a significant decrease in specific lymphocyte-venule binding and a significant increase in nonspecific binding. These findings suggest that radiation-induced damage to high endothelial venules might play a role in radiation-induced immunosuppression by interfering with the normal passage of lymphocytes from the blood into lymph nodes via a specific interaction between lymphocytes and high endothelial venules. 相似文献
6.
Durable immunity against fatal L. major infection in genetically susceptible mice can be induced by immunization with 150,000-rad irradiated or heat-killed promastigotes administered i.v. or to a lesser extent i.p. Conversely, subcutaneous (s.c.) and intramuscular (i.m.) injections are not only totally ineffective but generally increase susceptibility to and enhance the progression of the disease, leading to earlier mortality. This detrimental effect is particularly evident with lower infecting challenge doses. Disease exacerbation is apparent in mice given 4 X s.c. injections of as few as 2 X 10(4) irradiated promastigotes, but it appears most potent after doses of 2 X 10(7). When mice given 4 X s.c. injections were subsequently immunized i.v. with 2 X 10(7) irradiated promastigotes, they failed to develop any evidence of protection against infection with 2 X 10(5) promastigotes, whereas mice given i.v. immunization alone were strongly protected. Thus, s.c. injections are capable of blocking the prophylactic effect of i.v. immunization with irradiated parasites. This inhibitory effect can be achieved with a single s.c. injection, although rather less potently than with four, and is even effective against four repeated weekly i.v. immunizations. Once induced, the effect persists undiminished after 100 days. A weaker effect is also inducible by s.c. injection given after i.v. immunization. The blocking effect of s.c. injection is not dependent on continuing viability of the promastigotes, as it can be induced equally readily with heat-killed, formalin-fixed, or sonicated parasites. The phenomenon extends to mouse strains genetically resistant as well as susceptible to L. major infection and, in congenic mice of BALB background, is independent of the major histocompatibility (H-2) gene complex. 相似文献
7.
Therapeutic potential of rat monoclonal antibodies: isotype specificity of antibody-dependent cell-mediated cytotoxicity with human lymphocytes 总被引:5,自引:0,他引:5
The ability of rat monoclonal antibodies to promote antibody-dependent cell-mediated cytotoxicity with human effector cells was tested by using a variety of antibodies against different human and mouse leukocyte antigens. It was found that only IgG2b antibodies were effective. This isotype has already been shown to be efficient in fixing human complement, which suggests that among rat monoclonal antibodies, the IgG2b subclass might be a good choice for attempts at serotherapy. Further studies with other antibody-mediated effector mechanisms as well as suitable clinical trials are merited. 相似文献
8.
A prostaglandin omega-hydroxylase cytochrome P-450 (P-450PG-omega) purified from lungs of pregnant rabbits 总被引:2,自引:0,他引:2
D E Williams S E Hale R T Okita B S Masters 《The Journal of biological chemistry》1984,259(23):14600-14608
Cytochrome P-450-dependent prostaglandin omega-hydroxylation is induced over 100-fold during late gestation in rabbit pulmonary microsomes (Powell, W.S. (1978) J. Biol. Chem. 253, 6711-6716). Purification of cytochromes P-450 from lung microsomes of pregnant rabbits yielded three fractions. Two of these fractions correspond to rabbit lung P-450I (LM2) and P-450II (LM5), which together constitute 70-97% of total cytochrome P-450 in lung microsomes from nonpregnant rabbits. The third form, which we designate rabbit cytochrome P-450PG-omega, regioselectively hydroxylates prostaglandins at the omega-position in reconstituted systems with a turnover of 1-5 min-1. Titration with purified pig liver cytochrome b5, demonstrated a 4-fold maximum stimulation at a cytochrome b5 to a P-450 molar ratio of 1-2. Rabbit lung P-450PG-omega formed a typical type I binding spectrum upon the addition of prostaglandin E1 with a calculated K8 of 1 microM, which agreed reasonably well with the kinetically calculated Km of 3 microM. Cytochrome P-450PG-omega was isolated as a low-spin isozyme with a lambda max (450 nm) in the CO-difference spectrum distinguishable from P-450I (451 nm) and P-450II (449 nm). Sodium dodecyl sulfate-polyacrylamide slab gel electrophoresis demonstrated that although purified P-450PG-omega had a relatively low specific content (12.1 nmol mg-1), it appeared homogeneous with a calculated minimum Mr of 56,000, intermediate between rabbit LM4 and LM6. When lung microsomes from pregnant and nonpregnant rabbit were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, a protein band, with a Mr identical to P-450PG-omega, was observed in the pregnant rabbit, whereas this band appeared to be very faint or absent in microsomes from the nonpregnant rabbit. Purification of cytochromes P-450 from nonpregnant rabbit lung yielded only P-450I and P-450II. P-450PG-omega appears to be a novel rabbit P-450, possessing high activity towards omega-hydroxylation of prostaglandins, and is greatly induced during pregnancy in rabbit lung. 相似文献
9.
10.
Regional isolation perfusion with an alkylating agent was carried out in a small community hospital, using readily available equipment, ten times in nine cases of advanced malignant disease. Visible regression of tumor, either grossly or histologically, occurred in seven patients and decided subjective improvement occurred in five patients.The long range effect of the procedure could not be determined in the present series, not enough time having elapsed.Side effects included jaundice in four patients, massive necrosis of the tumor in one patient, nausea and vomiting in three patients, postoperative edema in five patients, wound infection in two patients, Horner''s syndrome in one patient, temporary alopecia in three patients, and depression of hemoglobin level in seven patients, of the leukocyte count in four patients and of the platelet count in four patients.A feature of the procedure used in the present series was a system of monitoring the escape of alkylating agent into the systemic circulation. 相似文献