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1.
Metabolites of corticosteroids that contain the 21-oic acid moiety are found in human urine. The acids from neutral steroids and urinary pigments have been separated by passing the mixture through a column of polyethyleneimine cellulose. The acids adhering to the column are quantitatively eluted with dilute formic acid. The purified preparation is suitable for derivatization and chromatographic analysis.  相似文献   
2.
Genomic DNA isolated from 20 horses was digested with up to six restriction endonucleases and subjected to southern blot hybridization analysis using various human class II alpha- and beta-chain cDNA probes. A high degree of restriction fragment length polymorphism (RFLP) was found for the DQ alpha, DP beta, DQ beta and DR beta probes, about 20 polymorphic bands being detected for each. DR alpha showed 2-4 polymorphic bands, whereas no evidence for DP alpha-like genes was found. A number of correlations of RFLPs with individual alloantisera were apparent.  相似文献   
3.
This study used monoclonal antibodies to sheep MHC class II molecules as well as an L cell transfectant (T8.1) which expresses DRA and DRB genes to show that two distinct DRβ chains are expressed in the sheep. Two anti-β chain specific monoclonal antibodies VPM37 and VPM43 react with DR antigen but not DQ antigen by ELISA. These two antibodies do not react with the DRβ chain expressed in the T8.1 cell line. Two-dimensional immunoblotting shows that these antibodies recognize a subgroup of the spots recognized by the DR-specific monoclonal antibody VPM57 which does react with the T8.1 β chain. Amino-terminal sequence analysis of the α chain associated with VPM37β chain shows that this α chain is homologous to the human DRα chain strongly indicating that the β chain is DR-like. VPM37 and VPM43 are shown to be directed against different epitopes on sheep MHC class II molecules so it is highly unlikely that the data can be explained by the presence of posttranslational modifications or the existence of a very common allele. These data provide clear evidence for the expression of two distinct DRP chains in the sheep.  相似文献   
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5.
Transecting the axons of neurons in the adult superior cervical ganglion (SCG; axotomy) results in the survival of most postganglionic neurons, the influx of circulating monocytes, proliferation of satellite cells, and changes in neuronal gene expression. In contrast, transecting the afferent input to the SCG (decentralization) results in nerve terminal degeneration and elicits a different pattern of gene expression. We examined the effects of decentralization on macrophages in the SCG and compared the results to those previously obtained after axotomy. Monoclonal antibodies were used to identify infiltrating (ED1+) and resident (ED2+) macrophages, as well as macrophages expressing MHC class II molecules (OX6+). Normal ganglia contained ED2+ cells and OX6+ cells, but few infiltrating macrophages. After decentralization, the number of infiltrating ED1+ cells increased in the SCG to a density about twofold greater than that previously seen after axotomy. Both the densities of ED2+ and OX6+ cells were essentially unchanged after decentralization, though a large increase in OX6+ cells occurred after axotomy. Proliferation among the ganglion's total non‐neuronal cell population was examined and found to increase about twofold after decentralization and about fourfold after axotomy. Double‐labeling experiments indicated that some of these proliferating cells were macrophages. After both surgical procedures, the percentage of proliferating ED2+ macrophages increased, while neither procedure altered the proliferation of ED1+ macrophages. Axotomy, though not decentralization, increased the proliferation of OX6+ cells. Future studies must address what role(s) infiltrating and/or resident macrophages play in regions of decentralized and axotomized neurons and, if both are involved, whether they play distinct roles. © 2002 Wiley Periodicals, Inc. J Neurobiol 53: 68–79, 2002  相似文献   
6.
Restriction fragment length polymorphism (RFLP) was used as a molecular genotyping approach to characterize differences in major histocompatibility complex class IV genes in meat-type chickens. A high level of polymorphism was observed following digestion with each of the two restriction endonucleases PvuII and BglII. Examination of DNA from 54 chickens revealed 23 polymorphic fragments. Application of RFLP techniques in the analysis of family groups should make possible the determination of B-G genotypes in the meat type chickens.  相似文献   
7.
Finite element scaling analysis is used to study differences in morphology between the craniofacial complex of normal individuals and those affected with the syndromes of Apert and Crouzon. Finite element scaling quantifies the differences in shape and size between forms without reference to any fixed, arbitrary registration point or orientation line and measures the amount of form change required to deform one object into another. Two-dimensional coordinates of landmarks digitized from annual sets of cephalometric radiographs were used in the analysis. A simple tabulation shows no difference in variances between the normal and pathological samples. A test of mean differences depicts the Apert and Crouzon morphologies as significantly different from normal. The Apert palate differs from normal in shape in the older age groups analyzed, and palatal size differences are most common at the posterior nasal spine. The Apert pituitary fossa and basi-occiput are significantly larger than normal. The Crouzon pituitary fossa is also larger than normal, but the difference is not always significant. The typical morphology of the Crouzon nose is due more to differences in shape than size. The Crouzon basi-occiput is significantly smaller than normal. An age association of the differences between the normal and pathological craniofacies was found in Apert syndrome but not in Crouzon syndrome. Apert syndrome is characterized by a more homogeneous pattern of craniofacial dysmorphology from 6 months to 18 years of age than Crouzon syndrome.  相似文献   
8.
We studied in the rat the effects of the drug etretinate (Tigason), given at three doses 3, 10, and 30 mg/kg body wt for 1 mo, on the concentrations of Na, K, Ca, Mg, Fe, S, P, Cu, and Zn in the plasma, brain, thymus, heart, liver, lung, kidney, testicle, muscle, and bone. The elements were simultaneously determined in tissues after nitric acid dissolution by inductively coupled plasma emission spectrometry using a JY 48 instrument. At the dose of 3 mg/kg, etretinate did not induce any statistically significant modifications of the element distribution. At the dose of 10 mg/kg, the main observed modifications were in plasma an increase of copper (+38%) and a decrease of zinc (-25%). At the highest dose of 30 mg/kg, some variations of the concentrations of elements in tissues were observed. But, on no account did retinoids induce an alteration of the mineral composition of bone, despite obvious macroscopic bone alterations.  相似文献   
9.
Arsenic compounds are known carcinogens. Although many carcinogens are also mutagens, we have previously shown that sodium arsenite is not mutagenic at either the Na+/K+ ATPase orhprt locus in Chinese hamster V79 cells. It can, however, enhance UV-mutagenesis. We now confirm the nonmutagenicity of sodium arsenite in line G12, a pSV2gpt-transformed V79 (hprt ) cell line, which is able to detect multilocus deletions in addition to point mutations and small deletions. The lack of arsenic mutagenicity has led to studies emphasizing its comutagenicity. Sodium arsenite at relatively nontoxic concentrations (5 μM for 24 h or 10 μM for 3 h) is comutagenic withN-methyl-N-nitrosourea (MMU) at thehprt locus in V79 cells. Using a nick translation assay, which measures DNA strand breaks by incorporating radioactive deoxyribonucleoside monophosphate at their 3′OH ends in permeabilized cells, we found that much more incorporation was seen in cells treated with MNU (4 mM, 15 min) followed by 3-h incubation with 10 μM sodium arsenite compared with cells exposed to the same MNU treatment followed by 3-h incubation without sodium arsenite. This result shows that in the presence of arsenite, strand breaks resulting from MNU or its repair accumulate over a 3-h period. We suggest that the repair of MNU-induced DNA lesions may be inhibited by arsenite either by affecting the incorporation of dNMPs into the MNU-damaged DNA template or by interfering with the ligation step.  相似文献   
10.
In the present study we report on the effects of commonly used nonsteroidal antiinflammatory drugs on metallothionein (MT) and MT-I mRNA levels. A single dose of chloroquine (100 mg/kg), diclofenac (100 mg/kg), indomethacin (10 mg/kg), or piroxicam (100 mg/kg) was administered ip to C57B1 mice. After 18 h, MT levels were determined with a Cd-saturation radioassay. MT-I mRNA levels were measured by Northern Blot analyses using a probe containing the mouse MT-I gene. All drugs tested caused an increase in the MT content of the liver but not of the kidneys and lung. The lowest and highest effects were observed with chloroquine (8 times the control value) and diclofenac (18 times), respectively. In accordance with the stimulation of MT synthesis, increased accumulation of hepatic MT-I mRNA could be demonstrated. These results indicate that elevated MT levels may contribute to the effectiveness of nonsteroidal antiinflammatory drugs in the treatment of rheumatoid arthritis (RA).  相似文献   
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