吉林省鼠疫自然疫源地达乌尔黄鼠的生态学研究

目的研究吉林省鼠疫自然疫源地乌尔黄鼠的生态学变化规律。方法依据《吉林省鼠疫自然疫源地现状调查实施方案及工作指南》对吉林省鼠疫自然疫源地达乌尔黄鼠种群的年龄结构、雌雄比和数量变化、雌性繁殖状况进行观察。结果2龄鼠占多数，4龄鼠较少，未发现大龄鼠，种群性比，雄：雌为1：0．98。雌鼠妊娠率94．32％，平均胎鼠数为7．67个。结论达乌尔黄鼠生态学各项指标变化差异略微，种数的数量年际动态基本是恒定的。     

Activated protein C resistance and lipoprotein (a) in young adults with branch retinal vein occlusion

We investigated the effects of activated protein C resistance (APCR), Factor V Leiden (FVL) mutation, and high lipoprotein (a) levels in 32 young patients with branch retinal vein occlusion (BRVO) vs 30 controls. No difference between patients with BRVO and controls was found with regard to APCR, FVL mutation, or lipoprotein (a) levels. These factors do not seem important in the etiology of BRVO. The authors have stated that they do not have a significant financial interest or other relationship with any product manufacturer or provider of services discussed in this article. The authors also do not discuss the use of off-label products, which includes unlabeled, unapproved, or investigative products or devices.     

Patellar angle in Osgood-Schlatter disease

A new patellar angle is described in lateral radiographs of the knee joint. One line is drawn along the articular surface of the patella and another from the end of the inferior articular cartilage to the patellar apex. The angle formed by these two lines averaged 33° in 68 knees joints afflicted with Osgood-Schlatter disease and 47° in 71 age-matched controls and 198 adult controls. The small angle in Osgood-Schlatter disease is proposed to be an important factor in the pathogenesis of the traction apophysitis.     

乙型肝炎病毒转基因小鼠体内肝靶向反义RNA抗病毒疗效研究

目的：探讨半乳糖修饰的反义RNA真核表达质粒在乙型肝炎病毒转基因小鼠体内的抗病毒作用。方法：以半乳糖多聚赖氨酸（Gal-PLL)作肝靶向载体，将乙型肝炎病毒基因C区的反义RNA真核表达重组质粒（pCEP4-aC）制备为Gal-PLL－pCEP4-aC。将24只血清HBV DNA、HBsAg阳性的小鼠，随机等分为Gal-PLL－pCEP4-aC治疗组、Gal-PLL-pCEP4对照组和生理盐水阴性对照组，于实验第1天尾静脉分别注射Gal-PLL－pCEP4-aC、Gal-PLL－pCEP4（100μg/只）和等体积的生理盐水，观察治疗前后血清HBV DNA以及HBsAg变化。结果：Gal-PLL－pCEP4-aC治疗组21天时血清HBV－DNA转阴率62．5％（5／8），且7，14，21天时血清HBsAg明显降低；而Gal-PLL－pCEP4组血清HBV DNA转阴1只（1／8），生理盐水组8只均未转阴，两组用药后血清中HBsAg与用药前比较差异性均不明显（P＞0．05）。结论：肝靶向反义RNA能在乙肝基因小鼠体内抑制HBV的复制和抗原表达。     

肾移植术后早期国产环孢素药动学的临床研究

目的:探讨肾移植受者术后早期服用国产环孢素的药动学变化特点。明确环孢素各时点血药浓度与时间曲线下面积(AUC)的相关关系。方法48例肾移植受者始服环孢素6mg/kg·d~(-1)1周后,按不同品种分环孢素组24例,赛斯平组14例及田可组10例,分别于服药即刻,服药后1、2、3、4、5、6、8、10、12h抽血查环孢素浓度(以C_0、C_1、C_2……C_(12)表示),比较不同品种药动学的变化特点。然后用逐步回归分析法计算环孢素的总体C_0、C_2、峰浓度C_(max),达峰时间(T_(max)),AUC以及各种指标的变异系数,并计算各浓度值与AUC的相关关系。结果三种国产环孢素在使用相同剂量时,C_0、C_2、C_(max)T_(max)及AUC差异均不显著,具有同质性。合并分析后,总体值C_0为(214.2±113.0)μg/L,总体C_(max)=C_2为(1048.0±378.7)μg/L,达峰时间(2.0±0.9)h,平均2h,AUC为(5106.4±1471.8)μg/(h·L)。抽血检测的10个时点浓度中,C_1、C_2、C_3、C_4、C_6、C_7与AUC的相关性有显著意义,其中C_2偏相关系数0.96最大,而变异系数(34.9％)相对较小。C_0不仅变异系数(52.8％)较大,且与AUC的相关性亦不显著。结论 国产环孢素总体峰浓度为C_2,与AUC具有较好的相关性,对AUC的变化影响大。可以将C_2作为临床一个常规的环孢素浓度监测指标。     

Transformation of immortal, non-tumorigenic osteoblast-like human osteosarcoma cells to the tumorigenic phenotype by nickel sulfate

Epidemiological studies have indirectly linked compounds ofchromium, nickel and arsenic to human carcinogenesis. However,there is no evidence that metal compounds can transform humancells to the tumorigenic phenotype in culture. We show herethat exposure to 36 µM NiS0₄ for 48–96 h resultsin transformation of an immortal, non-tumorigenic, osteoblast-likecell line, HOS TE85, to the tumorigenic phenotype. Continuouspassaging following treatment leads to the formation of a fewdense foci. The cells isolated and expanded from the foci aremorphologically transformed, and form anchorage-independentcolonies of the size and abundance comparable to that formedby Kirsten murine sarcoma virus transformed HOS TE85 cells.The transformed cells from tumors in nude mice, have enhancedlevels of plasminogen activators and have lost the ability toform model bone matrix on extended culture in the presence ofascorbic acid and ß-glycerophosphate. A number ofcell lines have been established from nude mouse tumors. Cytogeneticanalysis reveals 16 marker chromosomes and an aberrant chromosome16. This is the first report of the transformation of a humancell line to tumorigenic phenotype by a metal carcinogen.     

Problems in the design of anticancer agents

Theoretically, two predominant paths for obtaining more selective anticancer agents may be envisaged. These are: (a) to make compounds which distribute only or preferentially in cancer cells; (b) to make compounds that are able selectively to kill or to differentiate cancer cells. Although in the last two decades research into new anticancer drugs has not produced satisfactory results, there is solid ground on which novel strategies can be developed, mainly based on a much greater biological knowledge of human tumours. This article does not review all the possible approaches that may be followed, but simply discusses some ideas and problems mainly taken from the current research of our laboratory.     

Effect of a segregated-care system on patients' length of stay in intensive care

The Internal Medicine Residency Program of the Raritan Bay Medical Center's Perth Amboy Division was changed in July 1987 from a full continuity-of-care system to a unit-isolation one. The authors compared patients' data from the first two months of the academic years 1986-87 and 1987-88 and were unable to observe any impact of the change on length of stay in intensive care. However, informal interviews with the house staff members indicated that the change had a positive impact on their education, because of their closer observation of the pathophysiology of individual disease states and greater enjoyment of the time spent in critical care.     

Regulation of immunoglobulin heavy-chain gene rearrangements

Summary: Regulated assembly of antigen receptor gene segments to produce functional genes is a hallmark of B‐ and T‐lymphocyte development. The immunoglobulin heavy‐chain (IgH) and T‐cell receptor β‐chain genes rearrange first in B and T lineages, respectively. Both loci require two recombination events to assemble functional genes; D‐to‐J recombination occurs first followed by V‐to‐DJ recombination. Despite similarities in overall rearrangement patterns, each locus has unique regulatory features. Here, we review the characteristics of IgH gene rearrangements such as developmental timing, deletion versus inversion, D_H gene segment utilization, ordered recombination of V_H gene segments, and feedback inhibition of rearrangement in pre‐B cells. We summarize chromatin structural features of the locus before and during recombination and, wherever possible, incorporate these into working hypotheses for understanding regulation of IgH gene recombination. The picture emerges that the IgH locus is activated in discrete, independently regulated domains. A domain encompassing D_H and J_H gene segments is activated first, within which recombination is initiated. V_H genes are activated subsequently and, in part, by interleukin‐7. These observations lead to a model for feedback inhibition of IgH rearrangements.