Masson三色染色与HE染色在豚鼠牙齿组织石蜡切片中的比较研究及应用

针对牙齿组织形态学研究的难点,选择适宜固定液,用EDTA-2Na进行脱钙,完成了牙齿组织石蜡切片的制作。通过确定染色程序及各种染料的最佳作用时间,分别利用Masson三色染色法、传统的苏木精和伊红（HE）染色法对牙齿组织切片进行了染色观察。染色结果表明,与HE染色法相比,Masson三色染色更能使牙齿的各主要成分以不同颜色显现出来,色彩对比鲜明,亮丽润眼,为牙齿组织生理及病理组织形态学研究奠定了基础。针对机体中硬组织的相似特性,该试验方法可以在骨骼、软骨等硬组织的形态学研究中参考、改进并推广使用。     

骨质疏松症治疗药物的研究进展

骨质疏松症是以骨量减少、骨的微观结构退化为特征,致使骨的脆性增加并易于发生骨折的一种全身性骨骼疾病,是当前严重危害人类特别是绝经妇女和老人的疾病之一.近年来出现了许多预防和治疗骨质疏松症的药物,极大地推动了骨质疏松症理论基础的完善和临床治疗研究.就该领域的研究进展进行了简要综述.     

The oxygen resources of the hypolimnion of ionically enriched onondaga lake,NY, U.S.A.

The depletion of hypolimnetic DO and the upper depth boundary of anoxia for four different years (1978, 1979, 1980 and 1981), and the accumulation of sulfide for a single year (1981), are documented for ionically enriched hypereutrophic Onondaga Lake, NY, USA. The depletion rate, represented as the areal hypolimnetic oxygen deficit (AHOD, g m^?2 day^?1), was extremely high (1.2–2.7 g m^?2 day^?1), The large differences in the rate within individual years and from year to year were largely a result of differences in attendant vertical mixing (parameterized as the hypolimnetic heating rate). The entire hypolimnion (depth interval from 11 to 20 m) was without O₂ by late June of all 4 yr; anoxia was observed above the hypolimnion on some occasions when secondary stratification occurred. Sulfide accumulated progressively in the hypolimnion in 1981 following the onset of anoxia to a volume weighted concentration of I1 mg L^?1. The ionic discharge from an adjoining alkali manufacturer exacerbated the problem of limited O₂ resources of the hypolimnion by: (1) decreasing vertical mixing, (2) prolonging the duration of stratification, (3) causing abbreviated turnovers, and (4) encouraging increased rates of phytoplankton settling.     

The susceptibility of bovine udder quarters colonized with Corynebacterium bovis to experimental infection with Staphylococcus aureus or Streptococcus agalactiae.

Twenty bovine udder quarters colonized with Corynebacterium bovis SR6 and 20 uncolonized quarters were challenged by inoculation of Staphylococcus aureus Newbould 305 (ATCC 29740) into the teat cistern. The percentage of infection in quarters colonized with C. bovis (50%) was significantly lower than that in controls (100%). By similar challenge no significant difference was observed between the percentage of infection with Streptococcus agalactiae ATCC 27956 in 33 quarters colonized with C. bovis (70%) compared to 33 controls (87.9%). A total of 37 quarters colonized with C. bovis and 37 control quarters were challenged with Staph. aureus Newbould 305 (ATCC 29740) and Maxi (ATCC 27543) and Strep. agalactiae (ATCC 27956) by exposure of the teat orifice. The percentage of teat ducts colonized with C. bovis which became infected with either pathogen was not different from that for controls.     

Spontaneous gastric squamous cell carcinomas and other neoplasms in Greenland collared lemmings (Dicrostonyx groenlandicus).

Malignant neoplasms were present in 39/66 Dicrostonyx groenlandicus of varying ages, examined from a laboratory colony. The presence of multiple neoplasms in some resulted in an overall average of 1.15 tumors/affected animal. Gastric squamous papillomas were present in nine, and locally invasive or metastatic gastric squamous cell carcinomas in a further 36 animals. Three mammary adenocarcinomas, one pancreatic islet cell tumor, one probable pancreatic adenocarcinoma and one adrenal cortical adenoma were also seen in lemmings with gastric tumors. Two others had mammary adenocarcinoma alone, and one animal had bilateral Harderian gland adenocarcinoma. Lesions resembling glomerulonephrosis of rats were seen in 23/51 animals whose kidneys were examined. These findings were not considered artefacts of captivity since concurrent gastric squamous cell carcinoma, mammary adenocarcinoma and glomerulonephrosis were present in the single animal examined directly from the wild at Eskimo Point, Northwest Territories.     

An in vivo model for the study of Bordetella avium adherence to tracheal mucosa in turkeys

An in vivo model was developed for studies characterizing the adherence of Bordetella avium to the tracheal mucosa of turkeys. Three-week-old turkeys were anesthetized, and the cervical part of the trachea was isolated after tracheostomy was done. A hemostat was applied craniad to the tracheostomy site to occlude the tracheal lumen. Isolated tracheal segments were filled with an aqueous bacterial inoculum for 1 minute, and then excess inoculum and the hemostat were removed. After 1 hour, a 1-cm section was excised from each tracheal segment, and adherent viable bacteria were quantified. Modifications of the procedure were evaluated to produce a model that was technically simple to do, economical, and reproducible. To examine the validity of the model, adherence of B avium was compared with that of Escherichia coli and Staphylococcus aureus. Adherence of B avium to tracheal mucosa was 17 times greater than that with E coli and 1,550 times greater than that with S aureus. Colonization of the tracheal mucosa by B avium was demonstrated in tracheal sections obtained 6 hours after filling with bacterial inoculum. Because the ciliary clearance mechanism of the tracheal segments remained functional, washing of the tracheal lumen had no effect on numbers of associated bacteria. An important advantage of this model over in vitro models is the excellent preservation of the tracheal mucosal surface.