Injection vs. oral administration of folic acid in the chick     

FROST DV  DANN FP 《Science (New York, N.Y.)》1946,104(2708):492-493

  相似文献   

Intravenous utilization of partial acid hydrolysates of proteins     

RISSER WC  SCHENCK JR  FROST DV 《Science (New York, N.Y.)》1946,103(2673):362

  相似文献   

用新城疫病毒人工感染火鸡的试验研究     

孙宗禹  刘文周  刘哲仁  张凤林 《黑龙江畜牧兽医》1986,(7)

鸡新城疫(ND)在自条件下除鸡感染外,也不同程度的感染其它禽类。关于火鸡对ND的感染性问题,国外有不同的报道:有人认为火鸡与鸡对ND具有相同的易感性;而另有报道,火鸡对ND的易感性不如鸡敏感,鸡群中流行ND时,与病鸡接触的成龄火鸡出现轻微的临床经过而康复;也有报道雏火鸡感染ND后死亡率高,而3月龄以上的火鸡很少死亡,人工感染时,多数火鸡仅呈轻微经过。鉴于当前我省养火鸡单位和农家不断增加,为保证火鸡业的发展,在生产实际中迫切需要制定出火鸡的ND免疫程序。为此,首先用标准毒株在实验室内感染火鸡和火鸡  相似文献   

Chemical composition and structural features of the macromolecular components of plantation Acacia mangium wood     

Pinto PC  Evtuguin DV  Pascoal Neto C 《Journal of agricultural and food chemistry》2005,53(20):7856-7862

The wood of Acacia mangium, a prominent fast-growing plantation species used in the pulp-and-paper industry and, so far, poorly investigated for its chemical structure, was submitted to a detailed characterization of its main macromolecular components. Lignin (28% wood weight) isolated by mild acidolysis and characterized by permanganate oxidation, 1H and 13C NMR, and GPC, showed a very low content of syringylpropane-derived units (S:G:H of 48:49:3), a high degree of condensation, a low content of beta-O-4 ( approximately 0.40-0.43 per C6) structures, and a Mw of 2230. Glucuronoxylan (14% wood weight) isolated by alkaline (KOH) or by dimethyl sulfoxide extraction was characterized by methylation analysis, 1H NMR, and GPC. About 10% of the xylopyranose (Xylp) units constituting the linear backbone were substituted at O-2 with 4-O-methylglucuronic acid residues. Almost half of the Xylp units (45%) were O-2 (18%), O-3 (24%) or O-2,3 (3%) acetylated. X-ray diffraction analysis of cellulose (46% wood weight), isolated according to the Kürschner-Hoffer method, showed a degree of crystallinity of 67.6%.  相似文献   

Breast-feeding initiation and exclusive breast-feeding in rural Vietnam     

Duong DV  Binns CW  Lee AH 《Public health nutrition》2004,7(6):795-799

OBJECTIVE: To investigate the initiation of breast-feeding and exclusive breast-feeding within the first week after delivery for women in rural Vietnam. DESIGN: An interviewer-administered survey was conducted on a sample of rural women who gave birth during August-October 2002. SETTING: Quang Xuong District, Thanh Hoa Province of Vietnam. SUBJECTS: Four hundred and sixty-three women participated in the study, of whom 181 delivered at the district hospital (39.1%), 229 at a commune health centre (49.5%) and 53 at home attended by a traditional birth attendant (11.4%). RESULTS: Although the initiation and exclusive breast-feeding rates were relatively high at 98.3% and 83.6% respectively, the premature introduction of complementary food was a great concern. Logistic regression analysis showed that, together with socio-cultural determinants such as feeding preferences of the husband and maternal grandmother, feeding practices of friends, factors relating to delivery methods, delivery locations and health problems could influence the initiation rate and breast-feeding patterns. CONCLUSIONS: To promote breast-feeding practices of rural mothers, health education on breast-feeding should take into account local socio-cultural features in addition to improving the counselling skills of health workers.  相似文献   

Comprehensive study on the chemical structure of dioxane lignin from plantation Eucalyptus globulus wood   总被引：2，自引：0，他引：2  

Evtuguin DV  Neto CP  Silva AM  Domingues PM  Amado FM  Robert D  Faix O 《Journal of agricultural and food chemistry》2001,49(9):4252-4261

Results of a comprehensive study on the chemical structure of lignin from plantation Eucalyptus globulus Labill are presented. Lignin has been isolated by a modified mild acidolysis method and thoroughly characterized by functional group analysis, by a series of degradation techniques (nitrobenzene oxidation, permanganate oxidation, thioacidolysis, and Py-GC-MS), and (1)H and (13)C NMR spectroscopy. Plantation Eucalyptus globulus lignin was found to be of the S/G type with an extremely high proportion of syringyl (S) units (82-86%) and a minor proportion of p-hydrophenyl propane (H) units (roughly 2-3 mol %). Unknown C-6 substituted and 4-O-5' type syringyl substructures represent about 65% of lignin "condensed" structures. Eucalypt lignin showed high abundance of beta-O-4 (0.56/C(6)) structures and units linked by alpha-O-4 bonds (0.23/C(6)). The proportion of phenylcoumaran structures was relatively low (0.03/C(6)). Different kinds of beta-beta substructures (pino-/syringaresinol and isotaxiresinol types) in a total amount of 0.13/C(6) were detected. ESI-MS analysis revealed a wide molecular weight distribution of lignin with the center of gravity of mass distribution around 2500 u.  相似文献   

Clone30与Lasota疫苗对雏鸡免疫后HI抗体消长规律的试验     

刘文周  孙宗禹 《东北农业大学学报》1989,(3)

以血凝抑制试验方法,对同日龄雏鸡群,在同样饲养管理条件下,分别以Clone 30,Lasota两种新城疫弱毒疫苗,采用不同免疫途径,比较其免疫后的血清中HI抗体滴度的消长规律。结果表明,两种疫苗免疫后HI抗体消长规律基本相同。  相似文献   

Endosperm protein synthesis in maize mutants with increased lysine content     

Misra PS  Jambunathan R  Mertz ET  Glover DV  Barbosa HM  McWhirter KS 《Science (New York, N.Y.)》1972,176(4042):1425-1427

The endosperm proteins of the maize mutants, opaque-2, opaque-7, floury-2, brittle-2, and the double mutant of opaque-2 and brittle-2, were separated into five soluble fractions by the Landry-Moureaux method. As compared to their isogenic normal counterparts, the mutant endosperms had higher concentrations of albumins, globulins, and glutelin-3, and lower concentrations of prolamines. The combination of the opaque-2 and brittle-2 genes enhanced this difference. Although the four mutant genes are located on three different chromosomes, they exert a similar effect on endosperm protein composition. Five other starchmodifying mutants with high lysine content resemble the brittle-2 mutant in endosperm protein composition, when the gene is present either singly or combined with opaque-2. Therefore, the pattern of protein synthesis in all maize mutants with high lysine concentrations may be either identical or very similar. Because no synergistic effect on lysine concentration is obtained when floury-2 is combined with opaque-2, different pathways leading to reduced zein synthesis may exist in the floury and starch-modifying mutants with high lysine concentrations.  相似文献   

ETHYLENE INJURY TO CUT FLOWERS IN COLD STORAGE ROOMS     

Lumsden DV  Wright RC  Whiteman TM  Byrnes JW 《Science (New York, N.Y.)》1940,92(2385):243-244

  相似文献   

Soliton self-frequency shift cancellation in photonic crystal fibers     

Skryabin DV  Luan F  Knight JC  Russell PS 《Science (New York, N.Y.)》2003,301(5640):1705-1708

We report the cancellation of the soliton self-frequency shift in a silica-core photonic crystal fiber with a negative dispersion slope. Numerical and experimental results show that stabilization of the soliton wavelength is accompanied by exponential amplification of the red-shifted Cherenkov radiation emitted by the soliton. The spectral recoil from the radiation acts on the soliton to compensate for the Raman frequency shift. This phenomenon may find applications in the development of a family of optical parametric amplifiers.  相似文献