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201.
202.
We measured the effect of a common baby food, strained pears, on the absorption of iron from human milk. Five adult subjects were initially fed 1 dL of human milk that contained added ferrous citrate Fe 59; the same subjects were later fed human milk and one jar of baby food. Incorporation of 59Fe into RBCs averaged approximately one quarter of the administered iron from the human milk. When the milk was combined with the baby food, incorporation was significantly decreased. The addition of a supplemental food to the diet of the breast-fed infant impairs the bioavailability of the iron from human milk.  相似文献   
203.
204.
The degradation and excretion of 2-14C-uric acid were examined in three adult woolly monkeys (Lagothrix lagothrichia) to determine the basis for the relatively high serum and urinary uric acid concentrations previously reported in this species. Like man and the great apes which lack uricase, but in distinction to most other mammals, these animals converted very little urate to allantoin. Uric acid turnover, as has been reported for other New World monkeys, was several times that of normal man. Renal urate excretion as well as disposition by extrarenal mechanisms may protect Lagothrix vrom hyperuricemia. The capacity to convert urate to allantoin appears to have been lost late in the evolution of New World monkeys. The woolly monkey deserves further study as a primate model for investigations of enzyme replacement strategies.  相似文献   
205.
Multifocal Best's vitelliform dystrophy   总被引:3,自引:0,他引:3  
Three members of a family had multifocal, macular and extramacular--Best's vitelliform dystrophy. The lesion in one patient was observed over a ten-year period. A striking symmetry of locale and evolution of these lesions is noted between the eyes of a patient as well as among the three members of the family. The pseudohypopyon of the vitelliform cyst and the vitelliform deposits showed fluorescence before fluorescein injection. A hypofluorescent halo surrounded most lesions.  相似文献   
206.
Wear-resistance sliding-friction tests of high-strength corrosion-resistant nitrogen-bearing 08Kh14AN4MDB and 05Kh22AG15N8M2F steels have been performed for different structural states under sliding-friction conditions. The wear resistance of these steels depends on the intensity of the strain hardening of austenite. The martensitic-austenitic 08Kh14AN4MDB steel has a higher wear resistance if it has a high nitrogen-austenite concentration. The dependence of the weight loss of the 05Kh22AG15N8M2F and 12Kh18N10T steels on the test time is found to be linear.  相似文献   
207.
When the projecting point of saphenous nerve in second somatosensory cortex (S II) of cat was stimulated, the evoked potentials elicited by C-fiber inputs of saphenous nerve recorded in the primary somatosensory cortex (C-CEP) might be either inhibited or facilited according to whether the superficial and/or the deeper layer of the cortex was stimulated. The inhibition was expressed as a decrease of amplitude and prolongation of latency of C-CEP; while the facilitation, as an increase of amplitude and duration of C-CEP. When the superfaicial layer of S II was stimulated by weaker current, both inhibitory and facilitatory effects could be observed, but only inhibitory effect was observed, when the deep layer was stimulated. With the same intensity of stimulation, inhibitory effect was more pronounced when the deep layer rather than the superficial layer was stimulated. It is suggested that S II may play a role in the modulation of C-CEP of S I.  相似文献   
208.
本文叙述了用n-p散射方法刻度快中子探测器效率的基本原理、实验方法和测量结果。400 keV氘束轰击T-Ti靶,由T(d,n)~He反应得到15.2 MeV的中子,散射体是一个圆柱塑料闪烁体(φ2.2×3cm),飞行距离2m,时间分辨率约1.5ns,效率测量的能区范围为1—14MeV,对多次散射和几何条件作了修正,总的误差约2%。  相似文献   
209.
This paper describes a novel approach, termed the 'phage amplification assay', for the rapid detection and identification of specific bacteria. The technique is based on the phage lytic cycle with plaque formation as the assay end-point. It is highly sensitive, quantitative and gives results typically within 4 h. The assay comprises four main stages: (1) phage infection of target bacterium; (2) destruction of exogenous phage; (3) amplification of phage within infected host and (4) plaque formation from infected host with the aid of helper bacteria. A key component of this assay is a potent virucidal agent derived from natural plant extracts, pomegranate rind extract (PRE). In combination with ferrous sulphate PRE can bring about an 11 log-cycle reduction in phage titre within 3 min. This is achieved without any injury to the infected target bacteria. Subsequently, any resulting plaques are derived only from infected target organisms. Data are presented for a range of bacterial hosts including Pseudomonas aeruginosa, Salmonella typhimurium and Staphylococcus aureus. The detection limit for Ps. aeruginosa was 40 bacteria ml-1 in a time of 4 h and 600 bacteria m-1 for Salm. typhimurium. Application of the principles of this technology to other bacterial genera is discussed.  相似文献   
210.
We have developed a computer program for the rapid assessment of the primary structure differences between a protein of unknown sequence and a homologous known protein. Both proteins are reduced, alkylated, and digested with the same hydrolytic agent. The unfractionated peptide mixtures are submitted to automatic sequence analysis. Based on the knowledge of the reference sequence, the program utilizes the analysis data to identify all the potential peptides present in the two mixtures, determining their primary structure, homology degree, and molecular weight calculated both as integer MH+ and average mass variables. These fingerprints allow the user to easily identify the structural differences between the two proteins and clarify possible doubts by a mass spectrometric analysis of the two mixtures. In order to verify the utility of the program, we provide an application example using the already reported data of two homologous proteins.  相似文献   
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