老年性痴呆的病理特征与防治对策

老年痴呆症的发生与AB以及Tau蛋白的错误折叠密切相关，是蛋白质折叠相关的疾病，早期诊断是预防老年痴呆症的首要任务，而综合治疗是人类对抗老年痴呆症的必然举措。     

吸入性损伤犬降钙素的变化

目的单因素观察吸入性损伤或烧伤后血清免疫反应性降钙素(iCT)的变化,分析其诊断意义。方法将24只犬随机分为单纯吸入性损伤后中度(A)、重度(B)、特重度损伤(C)组及单纯重度烧伤(D)组,每组6只。吸人性损伤犬均在伤后6 h行纤维支气管镜检查,以明确其损伤程度。分别于不同时相点抽取犬静脉血检测iCT含量,抽取动脉血做血气分析。结果(1)经纤维支气管镜检查,证实A、B、C组犬符合吸入性损伤的预期程度。(2)与伤前值(38±22)ng／L比较,各组吸人性损伤犬iCT含量在伤后1 h均明显升高(P<0．05),伤后4 h明显高于D组(P(0．05),其中A组于24 h达峰值(453±224)ng／L,B、C组在48 h内呈进行性升高。D组犬iCT含量在伤后2 h开始持续升高,至伤后48 h为(125±41)ng／L。(3)血气分析结果显示,与伤前值(109±8)mm Hg (1 mm Hg=0．133 kPa)比较,A、D两组氧分压(PaO2)伤后各时相点无明显差异(P>0．05),B、C组犬从伤后8 h和伤后4 h开始持续下降,分别为(65±6)、(71±9)mm Hg。与二氧化碳分压(PaCO2)的伤前值(38±5)mm Hg比较,C组犬伤后24 h PaCO2开始升高[(52±11)mm Hg]。结论在吸入性损伤后8 h内,iCT的变化明显早于血气分析指标,其诊断意义接近纤维支气管镜检查。     

Nerve conduction as a means of estimating early post-mortem interval

Summary Methods in current practice for ascertaining time of death are largely based on the cooling of the body after death and are somewhat unreliable. A theoretica relationship is known to exist between the decline in the properties defining nerve conduction and time after death caused by the gradual cessation of metabolic activity in nerves. A number of such properties were measured in rats during life and after death. In most cases the relationship was found to be inconsistent. The chronaxie of the strength duration curve for the sciatic nerve was, however, found to increase consistently and reproducibly in a linear fashion over the first 90 min after death to a plateau value which was maintained beyond 135 min. These findings are discussed as the possible basis of a forensic method of determining the duration of the “post mortem interval” within the first few hours after death.      

EPF单克隆抗体杂交瘤细胞株的建立

本文用纯化的早孕因子免疫ＢＡＬＢ／Ｃ小鼠，通过鼠－鼠杂交瘤技术，成功地建立了２株分泌ＥＰＦ单克隆抗体的杂交瘤细胞。经检测，它们所分泌的抗体亚类均为ＩｇＧ１，毁交瘤染色体数目１００－１０６条，ＥＩＳＡ检测诱生腹水抗体效价为１：１．２８＊１０＾５，连续培养生物学性状稳定。抗ＥＰＦ抗原的单克隆抗体的建立，为深入研究ＥＰＦ的生物学性质、特征提供了有力的工具。     

Early laparoscopic cholecystectomy for acute cholecystitis

Background: The timing of laparoscopic cholecystectomy for acute cholecystitis remains controversial. Methods: One hundred ninety-four patients with acute cholecystitis were reviewed. The conversion rates for the various number of days of symptoms before surgery were analyzed. The conversion rate dramatically increased from 3.6% for those patients with 4 days of symptoms to 26% for those patients with 5 days of symptoms. The mean number of days of symptoms prior to surgery in those patients who underwent successful laparoscopic cholecystectomy was 4.1 as compared to 8.0 in those patients who required open cholecystectomy (p < 0.0001). Based on this data the patients were divided into two groups. Group 1 consisted of 109 patients who underwent laparoscopic cholecystectomy within 4 days of onset of symptoms and group 2 consisted of 85 patients who underwent laparoscopic cholecystectomy after more than 4 days following onset of symptoms. Results: The conversion rate from laparoscopic to open cholecystectomy was 15%. The conversion rate for group 1 was 1.8% as compared to 31.7% for group 2 (p < 0.0001). Indications for conversion were inability to identify the anatomy secondary to inflammatory adhesions (68%), cholecystoduodenal fistula (18%), and bleeding (14%). The major complication rate for group 1 was 2.7% as compared to 13% for group 2 (p= 0.007). The mortality rate for all patients with attempted laparoscopic cholecystectomy for acute cholecystitis was 1.5%. The average procedure time for group 1 was 100 ± 37 min vs 120 ± 55 min in group 2. The average number of postoperative hospital days in group 1 was 5.5 ± 2.7 days as compared to 10.8 ± 2.7 days in group 2. Conclusions: We advocate early laparoscopic cholecystectomy within 4 days of onset of symptoms to decrease major complications and conversion rates. This decreased conversion rate results in decreased length of procedure and hospital stay. Received: 28 March 1996/Accepted: 12 September 1996     

智力低下者皮纹特征研究

通过对８３例智力低下者（男５８人，女２５人，ＩＱ２５～８９）的１７项指纹指标和７项掌纹指标特征的观察分析，并与７５２例中等智力者（男３７０人，女３８２人，ＩＱ９０～１０９）的指纹和掌纹进行比较。结果表明，两组间有１０项指标存在显著差异或高度差异，其中Ｗｃ、Ｗｂ、ｗＡｃ、Ｌ、Ｓｄ和Ｔｈ／１的真实花纹等６项指标与智力呈负相关；Ｗｓ、ｗｄｌ、Ｌｕ、ＰＴＣ等４项指标与智力呈正相关。同时，作者提出了Ｗｃ、Ｗｂ、ＷＡｃ、Ｓｄ和ＰＴＣ的正常值，其可作为判定智力低下的重要生物学指标，为筛查弱智儿童提供了一种简便易行的方法。作者还为皮纹学的研究方向提出了新的建议。同时，作者还发现了一种新的皮纹型，暂命名为Ｗｂ。     

Computers in the Kindergarten

The computer use of two classrooms of kindergarten aged children in private school in Chicago were compared for variance in terms of the age and sex of the children, for variance by classroom, and for variance in the software selected. The major statistical method used was analysis of variance. There were two dependent variables: total frequency of computer use and the difference between the frequency in the first half and that in the second half (in order to examine the changing pattern of computer use in the two classrooms). There was no significant difference in computer use by sex or age, but there was a significant difference in the frequency of computer by classroom in the second half of the project compared to the first half. There was no significant difference in the software selected.     

Retinoic acid induced heparin-binding protein expression and localization during gastrulation,neurulation, and organogenesis

Retinoic acid induced heparin-binding protein (RIHB) is a highly basic, soluble polypeptide of the chick embryonic extracellular matrix. We have examined the expression and localization of RIHB during very early embryogenesis by in situ hybridization and immunohistochemistry. RIHB mRNA is very weakly detectable above background in the blastodiscs of unincubated eggs. The expression increases greatly over the first 24 hours of incubation, and is observed throughout the blastodisc in all three of the germ layers following gastrulation. As neurulation occurs, the expression becomes more restricted to certain areas, notably the ectoderm, the neural folds, and especially the notochord. After the neural tube has formed the expression in the tube itself decreases dramatically, whereas the expression in the head ectoderm and the notochord persists. After 72 hours of incubation expression remains relatively high throughout most of the embryo, with higher levels of expression in regions undergoing organogenesis and lower levels in organs which have already differentiated. RIHB protein is also weakly detectable in unincubated eggs as patches of immunoreactive material between the blastodisc and the vitelline. After 6 hours of incubation small regions of basement membrane are immunoreactive. RIHB is detected in this matrix, apparently before even fibronectin. The amount of RIHB protein increases dramatically over the first 24 hours of incubation. It is found in basement membrane separating the epiblast from the hypoblast, then later in that separating the ectoderm from the mesoderm. It is also detected surrounding individual cells, especially of the ectodermal layer. During neurulation RIHB is observed in the basement membrane surrounding the neural fold and the notochord, and in the lamina separating the ectodermal, mesodermal, and endodermal layers. Later in development, RIHB is detected in the basement membrane under the epidermis, throughout the developing limbs, and in the lamina of various developing organs, such as the eye, the pulmonary bud, the intestine, and the mesonephros. These results demonstrate that RIHB is highly expressed during the early embryonic period, by all three germ layers, and is an important and very early component of the embryonic extracellular matrix. Its very broad expression and localization argue for a more general role in development than its demonstrated weak neurotrophic activity. © 1994 Wiley-Liss, Inc.     

Diethylnitrosamine-induced metastasizing hepatocellular carcinomas in New Zealand white rabbits

Summary The aim of this study was to produce large liver tumors reliably, and to diagnose the tumors during development. Therefore, New Zealand white rabbits were treated withN-nitrosodiethylamine orally three times per week by gavage and were examined by clinical-chemical assay at regular intervals during the average treatment period of 14 months. The total cumulative dose was 1200 mgN-nitrosodiethylamine over 14 months. After a short treatment period the initial dose of 3 mg/kg had to be reduced to 1.5 mg/kg. In all 11 treated animals (100%) liver tumors were seen at the end of the study. Four control animals did not show any neoplastic changes. Clinical parameters investigated were for an assessment of liver function, total protein, urea, creatinine, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, albumin and neuraminic acid as well as some serum electrolytes. The in vivo diagnosis of liver tumors based on changes in these parameters proved to be relatively unreliable. The liver enzyme tests and urea concentration only yielded significant changes when the liver tumors were very large. Changes in neuraminic acid levels were the most reliable indicator for the presence of a liver tumor in this animal model. In the 11 treated animals, serum values of this marker increased towards the end of the study'by an average of 300 mg/dl. The induced tumors were mainly hepatocellular carcinomas. Only in 1 animal was a hepatocellular adenoma found. Further primary tumors diagnosed were six adenomas in the kidneys and two uterus adenomas, as well as nasal cavity tumors (two papillomas, one carcinoma, one adenoma and one adenocarcinoma). In 70% of the treated rabbits the hepatocellular carcinomas had metastasized to the lungs.     

Two-step hard acid deprotection/cleavage procedure for solid phase peptide synthesis

A new two-step deprotection/cleavage procedure for t-butoxycarbonyl (Boc) based solid phase peptide synthesis is reported. First the protective groups are removed from 4-(oxymethyl)-phenylacetamidomethyl (PAM) resin attached peptide with the weak hard acid, trimethylsilyl bromide-thioanisole/trifluoroacetic acid (TFA). In the second step, the peptide is cleaved from the resin with a stronger hard acid such as trimethylsilvl trifluoromethanesulfonate in TFA or with HF. The method is also shown to deformylate Nⁱⁿ-formyltryptophan moiety efficiently. The usefulness of this procedure for practical solid phase peptide synthesis is demonstrated by comparison with other deprotection methods in the synthesis of urotensin II and human endothelin.