Antigenicity of a synthetic peptide from glucosyltransferases of Streptococcus mutans in humans.

Human salivary immunoglobulin A (IgA) and serum IgG antibodies to the Streptococcus mutans glucosyltransferases (Gtfs) and to a synthetic peptide of 19 amino acids from a conserved region in the Gtfs (residues 435 to 453) were determined in young adults by enzyme-linked immunosorbent assay. Varying levels of antibody to Gtfs were detected in saliva or serum, with significantly higher levels of antibody to GtfD than to GtfB/C or GtfC. Anti-Gtf IgA levels in saliva did not correlate with those of IgG in serum. Caries-free (CF) volunteers exhibited significantly higher salivary IgA antibody levels to the peptide and to GtfB/C or GtfC than did the caries-active (CA) subjects. Preincubation of CF saliva and serum with the peptide inhibited the antibodies to the Gtfs in a dose-dependent manner, whereas preincubation of the samples from the CA group resulted in only partial inhibition. Our results indicated that this 19-amino-acid peptide includes one of the major B-cell epitopes of Gtfs and that CF individuals have higher titers of antibodies than CA subjects.     

青年人群血清流感抗体水平纵向监测

通过对北京４０５例青年１９９２～１９９４年流感抗体的纵向监测结果表明，３年中Ｂ型流感表现很活跃，抗体分别在１９９３年和１９９４年春出现高峰。Ａ型流感抗体在１９９３年春出现高峰。其中２１８例个体连续３年６次抗体检测，据抗体波动提示：３年中流感３个亚型总的感染频率为４４０％，每个体每年平均为１．４次，其中Ａ１型感染频率最高，每个体３年内平均１．８次；Ａ３型次之为１．５２；Ｂ型为１．０６。流感３个亚型抗体在机体内有６７％～７３％高水平抗体个体可在０．５～１年内下降至≤２０的低水平。２１８例个体中Ａ１型抗体３年内长期低水平者有３％，Ａ３有９％，Ｂ有３８％。     

棕榈油对成人血脂和血小板功能的影响

报道了棕榈油（ＰＡ），花生油（ＰＥ）对血清总胆固醇水平（ＴＣ）在５．５～７．０ｍｍｏｌ／Ｌ的受试者血脂和血小板功能的影响。５１名受试者（男３１人，女２０人，年龄３０～６６岁之间）分为两组，一组男１５人，女１１人，称ＰＥ组；另一组男１６人女９人，称ＰＡ组，预备期３周，膳食以当地日常食用的花生油烹调，实验期６周。ＰＡ组受试者食用以棕榈油烹调的实验膳；ＰＥ组受试者仍食花生油烹调的膳食。脂肪约占膳食能量的３０％，其中６０％～６５％来自实验油。实验结果表明：与起始值相比，６周末ＰＡ组受试者血清ＴＣ，低密度脂蛋白胆固醇（ＬＤＬ－Ｃ）和总胆固醇与高密度脂蛋白胆固醇比值（ＴＣ／ＨＤＬ－Ｃ）显著下降，血浆血栓素Ｂ２（ＴＸＢ２）／６－酮前列环素Ｆ１α、（６－ｋｅｔｏ－ＰＧＦ１α）比值显著下降，全血血小板聚集率未见显著变化。ＰＥ组受试者的血脂、血浆ＴＸＢ２、６－ｋｅｔｏ－ＰＧＦ１α及全血血小板聚集率等指标均未出现显著变化。提示，棕榈油作为我国居民家庭烹调用油并不会增加发生心血管疾病的危险。     

赤灵芝段木栽培新技术研究

短段木仿野生栽培灵芝是近年发展起来的灵芝人工栽培新法,应用于大规模生产。本文将栽培要点归纳为:熟材短段木断面接种室内培菌(野外)大棚覆土栽培。     

460例胃癌纤维胃镜活检标本的病理观察

本文分析了460例胃癌胃粘膜活检资料,结果:男:女为2.36:1:51～60岁年龄组发病率最岛(37.17％);发生部位以胃窦部最多见,占46.74％;组织学分类以低分化腺癌最多,占51 52％;在伴随病变中,畅化生的检出率为21.74％,胃腺囊为35％,胃粘膜上皮异型增生为32.61％。本组材料提示,不完全性大肠型肠化生、异型胃腺囊及胃粘膜中度以上异型增生与胃癌有密切关系。     

心肌和骨骼肌对低血钙不同反应性机理的初步研究

本实验采用枸椽酸钠等静脉输入复制家兔低血钙。实验动物血钙显著下降,同时出现骨骼肌抽搐和心肌收缩性下降。测定骨骼肌匀浆钙含量在低血钙前、后均比心肌匀浆高。认为这两种肌肉细胞内固有钙含量的差异,是低血钙时骨骼肌收缩亢进和心肌收缩性下降的原因之一,其次为神经肌肉的兴奋性改变。     

The effect of YAG laser anterior capsulotomy on prostaglandin concentration in aqueous humor

The YAG (yttrium aluminum garnet) laser has been recommended for anterior capsulotomies. One major complication is elevated intraocular pressure. We report a study of the biochemical content of the aqueous humor after a YAG laser anterior capsulotomy. We analyzed 6-keto-prostaglandin F1 alpha, thromboxane B2 and protein concentrations in the aqueous humor of human eyes. The average values of protein, 6-keto-prostaglandin F1 alpha, and thromboxane B2 in the control eyes were 81.3 +/- 14.0 mg/dL, 17 +/- 30 pg/mL, and 10 +/- 10 pg/mL, respectively. These values were elevated to 182.4 +/- 81.3 mg/dL, 401 +/- 55 pg/mL, and 576 +/- 148 pg/mL, respectively, after YAG laser anterior capsulotomy. The samples with a moderate level of 6-keto-prostaglandin F1 alpha (less than 300 pg/mL) had negligible changes of thromboxane. The elevation of thromboxane was obvious only when prostaglandin levels rose above 300 pg/mL.