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Normal batch dry rendering practice does not ensure sterile products, because bacterial spores are protected against thermal denaturation by the high fat-low water content environment which results from drying the materials at temperatures below those required for sterilization.  相似文献   
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Antibody prepared in I-E-subregion-incompatible strains (anti-A e s :E /k ) cross-reacts with I-A-subregion controlled A b : A /b and A q A q complexes. This cross-reaction defines a new I-region specificity designated Ia.50. The implications of this finding for the genetic origin of the I region and immuneresponse-gene function are discussed.  相似文献   
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The Klippel-Feil anomalad as part of the fetal alcohol syndrome   总被引:2,自引:0,他引:2  
R B Lowry 《Teratology》1977,16(1):53-56
A brother and sister and described with malformations and handicaps consistent with both the Klippel-Feil Anomalad and the Fetal Alcohol Syndrome. The mother was known to be a chronic alcholic throughout both pregnancies. It is suggested that these anomalies are not purely fortuitous but rather that maternal alcoholism may cause errors in cervical vertebrae segmentation.  相似文献   
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Summary The purpose of this investigation was to provide evidence for the secretion of high molecular weight mucins, CTM-A and CTM-B, in primary culture of canine tracheal epithelial (CTE) cells. The cells were isolated from tracheas of mongrel dogs by pronase treatment. Primary cultures of the epithelial cells were established using ICN cellagen inserts in Dulbecco’s modified Eagle’s/F12 medium supplemented with growth factors and could be maintained for up to 23 days. The evidence for the mucin secretion in culture medium and their localization in the cells was established by a) positive immunocytochemical staining using specific antibodies developed against purified native as well as deglycosylated CTM-A and CTM-B; b) incorporation of labeled amino acids, followed by electrophoresis and autoradiography detection of glycoconjugates purified from the culture medium; c) comparison of the amino acid compositions of mucin purified from canine tracheal pouch secretions and that purified from the culture medium; and d) Western blot analyses using specific polyclonal antibodies directed against deglycosylated CTM-A and CTM-B. Immunoaffinity purified secreted labeled glycoconjugates were resistant to hyaluronidase treatment. The effects of cyclic AMP (1 × 10−5 M), dibutyryl cyclic AMP (1 × 10−5 M), 8-bromocyclic AMP (1 × 10−5 M), and prostaglandin E1 (1 × 10−6 M) on mucin secretion by CTE cells were also investigated. Secretion of mucins by CTE cells in culture was considerably more enhanced by 8-bromocyclic AMP than that observed for other secretagogues used in this study.  相似文献   
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The proton and nitrogen (15NH-H alpha-H beta) resonances of bacteriophage T4 lysozyme were assigned by 15N-aided 1H NMR. The assignments were directed from the backbone amide 1H-15N nuclei, with the heteronuclear single-multiple-quantum coherence (HSMQC) spectrum of uniformly 15N enriched protein serving as the master template for this work. The main-chain amide 1H-15N resonances and H alpha resonances were resolved and classified into 18 amino acid types by using HMQC and 15N-edited COSY measurements, respectively, of T4 lysozymes selectively enriched with one or more of alpha-15N-labeled Ala, Arg, Asn, Asp, Gly, Gln, Glu, Ile, Leu, Lys, Met, Phe, Ser, Thr, Trp, Tyr, or Val. The heteronuclear spectra were complemented by proton DQF-COSY and TOCSY spectra of unlabeled protein in H2O and D2O buffers, from which the H beta resonances of many residues were identified. The NOE cross peaks to almost every amide proton were resolved in 15N-edited NOESY spectra of the selectively 15N enriched protein samples. Residue specific assignments were determined by using NOE connectivities between protons in the 15NH-H alpha-H beta spin systems of known amino acid type. Additional assignments of the aromatic proton resonances were obtained from 1H NMR spectra of unlabeled and selectively deuterated protein samples. The secondary structure of T4 lysozyme indicated from a qualitative analysis of the NOESY data is consistent with the crystallographic model of the protein.  相似文献   
40.
Measurement of 2-deoxyglucose and 2-deoxyglucose 6-phosphate in tissues   总被引:7,自引:0,他引:7  
The enzymatic methods previously described for 2-deoxyglucose (DG) and 2-deoxyglucose 6-phosphate have been refined and adapted to measurements of brain samples ranging from 50 mg wet weight to less than a microgram dry weight. Procedures for preparing such samples for assay are described. Analytical properties of the enzymes employed are given together with means for overcoming their possible short comings. Emphasis is placed on information useful for employing DG to assess rapid changes in glucose metabolism.  相似文献   
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