单颌全口义齿修复的探讨

单颌全口义齿修复的探讨龚晓兰单颌全口义齿，由于其对是天然牙，曲线往往有不同的变化，给修复带来了困难。因上、下颌咬力明显差异，常引起牙槽嵴的吸收，更是单颌全口义齿修复的难点。本文对１９９３年１～６月４０例单颌全口义齿修复病人进行临床分析，总结了单颌全口...     

Validation of commonly used immunostains on cell-transferred cytologic specimens

BACKGROUND: Immunocytochemical staining (ICC) is often limited by the lack of cell blocks that contain diagnostic cells or by the unavailability of smear materials. The cell-transfer technique, in which original smear material is divided into several pieces and then transferred to multiple slides, can facilitate multiple ICC on limited materials. However the reliability of the staining results has not been systematically evaluated. METHODS: The authors validated 21 commonly used antibodies (cytokeratin [CK] 7, CK 20, TTF-1, panCK, vimentin, HMB-45, Mart-1, leukocyte common antigen, chromogranin, synaptophysin, estrogen receptor, progesterone receptor, prostate-specific antigen, prostatic acid phosphatase, calretinin, CK5/6, WT-1, BerEP4, MOC-31, p63, and thyroglobulin) on the cell-transferred materials of various tumor samples (n = 20) and reactive effusion samples (n = 2). The staining results were compared with the previously available ICC results (performed either on cell block sections or on smears) of the same specimens. RESULTS: One hundred pieces of transferred materials were immunostained, of which 5 (5%) were lost during the staining procedure. Of the remaining 95 pieces, 92 (97%) showed staining results that agreed with those of the previous ICC, whereas 3 (3%) showed results that disagreed. The original ICC in the latter three specimens was performed on cell block sections and showed focally positive synaptophysin staining in a sample with a neuroendocrine tumor, focally positive CK5/6 staining in a pleural effusion sample with mesothelioma, and positive TTF-1 staining in a lymph node sample with metastatic lung carcinoma. Their corresponding ICC of cell-transferred materials showed negative results. An increase in background staining was observed in 1 of the 95 tissue pieces, but no false-positive results were observed. CONCLUSIONS: In general, ICC can be reliably performed on cell-transferred tissue specimens for markers tested. However, caution should be taken when interpreting ICC results in tissue specimens with limited cellularity and heavy background staining.     

Effects of Dietary Administration of CL-20 on Japanese QuailCoturnix coturnix japonica

Hexanitrohexaazaisowurtzitane, or CL-20, is an emerging highly energetic compound currently under consideration for military applications. With the anticipated wide use of CL-20, there is the potential for soil and groundwater contamination resulting in adverse toxicologic effects on environmental receptors. Presently, there is a lack of data describing the toxic effects of CL-20 on avian species. The present study describes the effect of CL-20 on Japanese quail (Coturnix coturnix japonica) modified from standard toxicity test guidelines. First, a 14-day subacute assay was adopted using repeated gavage doses (0, 307, 964, 2439, 3475, or 5304 mg CL-20/kg body weight (BW)/d for 5 days followed by no CL-20 exposure (vehicle only) for 10 days. Second, a subchronic feeding assay (0, 11, 114, or 1085 mg CL-20/kg feed) was done for 42 days. During both studies, no overt toxicity was observed in the CL-20–treated birds. During the first 5 days of the subacute study, CL-20–exposed birds showed a dose-dependent decrease in BW gain, whereas increased liver weight, plasma sodium, and creatinine levels were observed in birds receiving the highest dose tested. For the subchronic study, embryo weights were significantly decreased in a dose-dependent manner. Embryos from CL-20–exposed birds were observed to have multiple cranial and facial deformities, beak curvatures, possible mid-brain enlargement, and classic one-sided development with micro-opthalamia (nonstatistical comparisons with control embryos). A trend toward decreased number of eggs laid per female bird was also observed. We conclude that CL-20 (or its degradation products) elicits few effects in adults but may affect avian development, although these preliminary findings should be confirmed.     

老年髋部骨折的牵引治疗

目的了解因全身其他因素,不能接受手术治疗的老年髋部骨折患者,进行牵引治疗的结果。方法2000年11月至2005年1月共有102例老年髋部骨折患者,因伴有心脏病、糖尿病、高血压等内科疾病而行牵引治疗。其中股骨颈骨折37例,股骨粗隆间骨折65例,年龄48～98岁,平均75．8岁。所有病例均在家中接受牵引治疗。结果1年内死亡9例,死亡率8．8％（9／102）。其他并发症依次为褥疮30例,发生率29．4％（30／102）,肺部感染6例,发生率5．9％（6／102）,下肢深静脉血栓2例,肺栓塞1例,泌尿系感染1例。股骨颈骨折愈合15例,愈合率51．7％（15／29）。股骨粗隆间骨折愈合40例,愈合率97．6％（40／41）。调查时与伤前Harris评分比较,股骨颈骨折组平均下降23．1分,股骨粗隆间骨折组下降15．6分。结论对于无移位或稳定的股骨颈骨折,以及部分粗隆间骨折,牵引治疗可以获得良好的结果,且其花费低,在现阶段仍具有一定的适用范围。     

Regional variations in microstructural properties of vertebral trabeculae with aging

The aim of this study was to identify regional variations in the three-dimensional microstructure of vertebral cancellous bones, and their relative differences with respect to aging. Ninety trabecular specimens were obtained from six normal L4 vertebral bodies of six male cadaver donors in two age groups, three aged 62 years and three aged 69 years; (n = 45, each). In each vertebral body, five trabecular columns, each of 8 × 8 × 25mm³, were cut from the anterior, posterior, central, right, and left regions. These columns were scanned, using high-resolution micro-computed tomography (µCT), three times, to obtain superior, middle, and inferior layers. Fifteen regions were obtained for each vertebral body. For all 90 trabecular specimens the bone volume fraction (BV/TV), trabecular number (Tb.N), and trabecular thickness (Tb.Th), as well as the three radii of the mean intercept length (MIL) ellipsoid (H1, H2, and H3) were determined. Regional variations in different transverse layers and vertical columns within and between the two age groups were then analyzed. The results showed significant differences in BV/TV, Tb.N, DA, and H2/H3 between the two age groups. The BV/TV and Tb.N were decreased, while the anisotropic parameters were increased significantly with age, increasing from age 62 to 69. Change in Tb.Th was not statistically significant, although the average was slightly smaller in the 69-year group. Each microstructural parameter followed its own pattern of regional variation within each group, suggesting both mechanical and age-related adaptation. This is the first study that has provided microstructural data of the vertebral body in a Chinese sample. These data may help us to gain more insight into the mechanism of the occurrence of lumbar osteoporosis and the related regional fracture risks, and may provide a reference for better enhancement of fracture repair.     

Preparation and characterization of SARS in-house reference antiserum

A reference antiserum for SARS is in urgent need in the development of SARS vaccine and other serological test of SARS research. Convalescent serum was collected from clinical confirmed patient. ELISA, Western-blotting and neutralization assay detected specific antibody against SARS coronavirus. This antiserum was prepared as in-house reference antiserum, freeze-dried and sealed in ampoules. The potency of this reference antiserum is defined to be 52.7 U after extensive calibration. Further, collaborative studies for the evaluation of this serum are needed in order to satisfy the requirements for international reference antiserum.     

The calcium-dependent protease calpain causes endothelial dysfunction in type 2 diabetes

Cardiovascular complications are the leading cause of morbidity and mortality in diabetic patients. Endothelial dysfunction with impaired endothelial nitric oxide (NO) synthase (eNOS) activity is a widely accepted cause of diabetic vasculopathy. The mechanisms of endothelial dysfunction in diabetes remain elusive, thus limiting effective therapeutic interventions. We report novel evidence demonstrating that the calcium-dependent protease calpain causes endothelial dysfunction and vascular inflammation in the microcirculation of the ZDF (Zucker diabetic fatty) rat, a genetic rat model of type 2 diabetes. We found evidence of increased calpain activity and leukocyte trafficking in the microcirculation of ZDF rats. Inhibition of calpain activity significantly attenuated leukocyte-endothelium interactions in the vasculature of ZDF rats. Expression of cell adhesion molecules in the vascular endothelium of ZDF rats was consistently increased, and it was suppressed by calpain inhibition. In vivo measurement of endothelial NO availability demonstrated a 60% decrease in NO levels in the microcirculation of diabetic rats, which was also prevented by calpain inhibition. Immunoprecipitation studies revealed calpain-dependent loss of association between eNOS and the regulatory protein heat shock protein 90. Collectively, these data provide evidence for a novel mechanism of endothelial dysfunction and vascular inflammation in diabetes. Calpains may represent a new molecular target for the prevention and treatment of diabetic vascular complications.