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31.
Fifty-four clones containing human inserts were selected from a cosmid library constructed from a somatic cell hybrid containing chromosome 11p15.3-p15.5 as its only human complement. In 32 of these clones, 63 polymorphic systems were identified with a panel of restriction enzymes: 57 conventional RFLP systems and 6 highly polymorphic VNTR systems. Although we examined the cosmid with only seven enzymes, 18 clones (including 6 VNTRs) were polymorphic with three or more enzymes. The results suggested that DNA sequences on the peritelomeric region of chromosome 11p tend to be highly variable. Because these markers are highly informative, they will be excellent resources for investigations of hereditary diseases and tumor suppressor genes in this region of chromosome 11.  相似文献   
32.
The pea phytochrome I (PI) cDNA clone, pPP1001, was expressedin E. coli. The plasmid pPP1001 contains pea PI cDNA which coversthe entire coding region with the Shine-Dalgarno consensus sequencejoined upstream of the cDNA in an expression vector pNUT6. ThepPP1001 transformants formed typical inclusion bodies when culturedat 32?C. However, when cultured at 37?C or in the presence ofisopropyl-ß-D-thiogalactopyranoside (IPTG) at 32?C,the bacteria lysed before inclusion body formation. Immuno-stainingwith anti-PI monoclonal antibody, mAP5, of transformants fixedby cold methanol showed that stainable materials were distributedin whole cytoplasmic region. When the inclusion bodies wereobserved clearly, the regions corresponding to the inclusionbodies became difficult to stain. Western blot analysis, however,showed that a ca. 100 kDa PI polypeptide was detected in thefraction from inclusion bodies and a ca. 90 kDa PI polypeptidefrom the soluble fraction. The amino acid sequence analysisof purified 100 kDa PI sample indicated that its amino terminusis blocked. However, minor signals in one experiment yieldeda sequence corresponding to the expected amino terminus of peaPI except for the initiation methionine. One of the anti-peaPI monoclonal antibodies, mAP9, that recognizes the near N-terminusof pea phytochrome was reactive to the 100 kDa polypeptide. (Received June 22, 1990; Accepted November 18, 1990)  相似文献   
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A preparation method for 9-anthryldiazomethane (ADAM) as a fluorescent labeling reagent for carboxylic acids is described. 9-Anthraldehyde hydrazone is oxidized with an organic oxidant, N-chlorosuccinimide, in an organic solvent such as ethyl acetate to give ADAM, and then the reaction mixture is directly used as the reagent solution for the derivatization of carboxylic acids. Both the oxidation and the derivatization reaction are carried out at room temperature, and an aliquot of the derivatization mixture is directly injected into a chromatograph. 9-Anthrylmethyl ester derivatives formed from ADAM and various carboxylic acids are sufficiently separated on a reversed-phase column and are sensitively detected fluorometrically. The present method was applied to the high-performance liquid chromatographic determination of long and short chain fatty acids, keto acids, and hydroxy acids.  相似文献   
36.
A high-performance liquid chromatograph with a synchronized accumulating radioisotope detector was used to determine the turnover rate and pool size of tryptophan in rat. The specific radioactivity could be followed for three half-lives on the final slope of the specific radioactivity curve following intravenous administration of 15 muCi of carrier free tryptophan labeled with carbon-14. Remarkable individual differences were noted in turnover rate and in pool size among rats.  相似文献   
37.
The ovaries of the marine snail Turbo cornutus contain a number of pigments. So far, the presence of carotenoids and a chromoprotein with a bile pigment, called turboverdin (= 3(2)-hydroxy-mesobiliverdin IX alpha), as its prosthetic group are known. The present work describes the isolation and structure elucidation of two further bile pigments, biliverdin IX delta and neobiliverdin IX delta. This is the first report of naturally occurring bile pigments with IX delta structure.  相似文献   
38.
1. Human chorionic tissues were incubated with [14C]leucine and/or [3H]glucosamine, and fibronectin synthesis was examined. 2. Radio-labeled fibronectin was detected in the tissue fraction of the incubation mixture, but not in the medium fraction, indicating that fibronectin is synthesized and retained in the tissue. 3. The glycopeptides derived from 3H-labeled fibronectin showed the lectin-binding characteristics similar to those from unlabeled placenta fibronectin, but different from those of plasma fibronectin.  相似文献   
39.
T Yamaguchi  S Hanai 《Biorheology》1988,25(1-2):31-36
An electrochemical surface shear stress measurement was applied to a model of very thin unilateral arterial stenosis (height of 1/8 of the model pipe diameter with very smooth surface). Three dimensional wall shear stress distribution was measured under steady flow field from a relatively low Reynolds number, Re = 270, to a high Reynolds number, Re = 1200. There was a characteristic high and low wall shear distribution pattern around the stenosis. There were also remarkable high shear stress areas on the opposite wall and both side walls of the stenosis. It was clearly shown that three dimensional structure of the flow field, hence, the wall shear stress distribution, is affected by a minimal change on the arterial wall.  相似文献   
40.
We describe a patient with adult T cell Leukemia to whom alpha-interferon therapy was highly effective. Although a combination chemotherapy (ACVP) first introduced was effective in reducing total leukocyte counts, the percentage of leukemic cells relative to total leukocyte counts was decreased first after the institution of alpha-interferon therapy. The patient is now under complete remission for four years. It was noted in this patient that circulating alpha-interferon, measured by a sensitive radioimmunoassay, was consistently low as compared with the value found in the age-, sex-matched healthy control (p less than 0.001). Since adult T cell leukemia is pathogenetically related to the retrovirus infection, low levels of circulating alpha-interferon of the patient may be important from both pathogenetic and therapeutic standpoints. Alpha-interferon therapy may be an useful additive for the chemotherapy of adult T cell leukemia.  相似文献   
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