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81.
OBJECTIVE: Early graft failure (EGF) is a life-threatening event still accounting for a significant percentage of early deaths after heart transplantation. We tested whether selected metabolic markers, including high-energy phosphate concentrations measured ex vivo in pre-transplant heart grafts by (31)P magnetic resonance spectroscopy (MRS) are related with early post-transplant outcome. METHODS: During a 3-year period, 26 heart grafts harvested in the vicinity of the transplantation centre were studied. Evaluation of transplantability was done conventionally. (31)P MRS was performed ex vivo approximately 60min after aortic cross-clamp to quantify ATP, P(i) and PCr concentration ratios. A MRS-score was defined as a combination of intracellular pH (pHi) and the PCr/P(i) ratio. EGF was defined as the need to abnormally extend circulatory support or to use more than two inotropes before weaning the patient from CPB after transplantation. The grafts were attributed to three groups as follows: A1, transplanted with uneventful outcome (n=14); A2, transplanted with subsequent EGF (n=3) and B, not suitable for transplantation (n=9). RESULTS: Significant differences between groups existed for the following metabolic markers: PCr/ATP (P=0.013), PCr/P(i) (P=0.0004), pHi (P=0.0016) and MRS-score (P=0.0001). The sensitivity, specificity and positive likelihood ratio for EGF with a MRS-score相似文献   
82.
83.
Ultrasensitive bright field in situ hybridization assays using enzyme metallography (EnzMet) have been developed and validated, but little is known regarding the applicability of EnzMet for immunophenotypic detection of protein via IHC. Superior resolution via discrete metallographic deposits offers the potential for enhancing high-resolution immunophenotyping. Using high-complexity tissue microarrays (TMAs), 88 common solid tumors were evaluated by automated EnzMet (Nanoprobes and Ventana). Targets were chosen to assess the ability of EnzMet to specifically localize encoded antigens in the nucleus (estrogen receptor), cytoplasm (cytokeratins), and cytoplasmic membrane (HER2) in TMAs. Results were compared with conventional IHC diaminobenzidine (DAB) immunostaining. There was full concordance between the EnzMet and conventional IHC results. Furthermore, the EnzMet reaction products did not appreciably diffuse, were dense and sharply defined, and provided excellent high-resolution differentiation of cellular compartments in paraffin sections for the nuclear, cytoplasmic, and cell membrane-localized antigens evaluated. The higher density of elemental silver deposited during enzyme metallography permitted evaluation of core immunophenotypes at a relatively low magnification, allowing more tissue to be screened in an efficient manner. This preliminary study shows the utility of using enzyme metallography for high-resolution immunophenotyping in TMAs.  相似文献   
84.
Orthotopic placement of in vitro propagated Dunning R3327 AT-3 tumor cells resulted in a greater percentage of tumor takes and a two-fold shift in the exponential growth curve compared to flank implantation. The orthotopic tumor appeared to disseminate preferentially to regional lymph nodes, rather than to the lungs which is characteristic of flank tumors. The results suggest an important role of stromal-epithelial interactions in the growth of this tumor. © 1995 Wiley-Liss, Inc.  相似文献   
85.
A series of 5-alkyl-5-phenylbarbituric acid analogues were shown to be potent hypolipidemic agents in rats and mice at 20 mg/kg/day. This dose is lower than that required for hypolipidemic activity for clofibrate and nicotinic acid derivatives in rodents and man. These new derivatives reduced both serum cholesterol and triglyceride levels in rodents by either the oral or intraperitoneal route of administration. Previous studies have demonstrated that similar heterocyclic compounds, i.e. cyclic imides, glutarimides and hydantoins are potent hypolipidemic agents in rodents. The barbituric acid derivatives probably interfered with de novo synthesis of cholesterol and fatty acids in the early steps since the agents inhibit the activities of ATP-dependent citrate lyase and acetyl-CoA synthetase. Triglyceride synthesis may be blocked since the agents inhibited the rate limiting enzyme, sn-glycerol-3-phosphate-acyl-transferase. Rat tissue lipids especially cholesterol and triglycerides were reduced after 14 days treatment. Fecal lipids were increased in cholesterol and phospholipid content by selected compounds. The rat serum lipoprotein after 14 days drug administration showed reduced VLDL-cholesterol and HDL-triglyceride contents. The modulation of the lipid content of the serum lipoproteins by the barbituric acids suggest that these agents may be helpful in treating clinical hyperlipidemic disease states.  相似文献   
86.
The development and testing of candidate vaccines for trachoma are constrained because only humans and nonhuman primates are susceptible to conjunctival infection with Chlamydia trachomatis. Guinea pig inclusion conjunctivitis (GPIC), an analogous disease of guinea pigs, provides a useful, less expensive model to study ocular chlamydial infections. GPIC is caused by a Chlamydia psittaci strain whose external constituents are very similar to those of C. trachomatis. To develop a better model for studying GPIC immunity, conjunctival pockets were established under the abdominal skin of guinea pigs by subcutaneous implantation. Up to six implants could be produced in each animal. The success rate of implantation was 79.0% (n = 148). These pockets were then infected with GPIC. The organism was recovered from the autografts indicating local replication, and tests for serum antibody by microimmunofluorescence showed production of GPIC-specific antibody of IgG and IgM classes after infection. There was minimal antibody response after moderate inoculating doses to the implants, and the titers increased more slowly than after eye infection with GPIC; with higher concentration of the inoculum, however, the antibody response increased to the same levels as with the ocular challenge but more slowly. Inoculation of pockets with GPIC also produced acute inflammatory changes in infected autografts (n = 101). Histologic examination of infected grafts showed chlamydial inclusions in epithelial cells and significant infiltration with lymphocytes and polymorphonuclear cells. Subcutaneous autografts may provide a useful model for chronologic studies of chlamydial infection. The delayed immunologic response, however, suggests that these pockets of implanted epithelium do not have full access to the immune system.  相似文献   
87.
Poverty, health services, and health status in rural America   总被引:5,自引:0,他引:5  
Access to health services for everyone has been a major policy goal in the United States: inequitable access is assumed to lead to inequitable health status, particularly for low-income groups. A sophisticated model of the relation between poverty, health care needs, service use, and health outcomes is used to analyze cross-sectional data on 7,823 adults from 36 rural communities. Improved access and use are helpful, but evidence clearly indicates that combined health and social initiatives will be necessary to reduce inequalities in health status.  相似文献   
88.
Transforming growth factor-β1 (TGF-β1) is known to be a potent growth inhibitor for many cell types, including most epithelial cells. In skin keratinocytes, TGF-β1 has been shown to inhibit growth and to rapidly reduce c-mycexpression. However, the molecular mechanism of TGF-β1 action on cell growth of cervical carcinoma has not yet been elucidated. We thus assessed the effect of TGF-β1 on the growth of cervical carcinoma cell lines. Two cervical squamous carcinoma cell lines, CUMC-3 and CUMC-6, were incubated with varying concentrations of TGF-β1, and growth inhibition was evaluated with tetrazolium-based colorimetric assay. After culture in TGF-β1 for 24 h, inhibition of growth was detected in a dose-dependent manner at concentrations of 0.1–10 ng/ml in both cell lines. This effect of TGF-β1 on cultured carcinoma cells was associated with apoptotic process including oligonucleosomal ladder DNA and apoptotic body formations. Northern blot analysis revealed c-mycmRNA expression was suppressed by 10 ng/ml of TGF-β1 following 3 h of treatment in both cell lines. Western blot analysis showed that the level of p27Kip1protein was increased after TGF-β1 treatment in both cell lines. These results suggest that the mechanisms by which TGF-β1 inhibits the growth of cervical carcinoma are complex and may include effects on down-regulation of c-mycgene, and overexpression of p27Kip1protein.  相似文献   
89.
Volumes of medial and lateral temporal lobe structures were assessed using magnetic resonance imaging (MRI) in 11 patients with late-life onset schizophrenia (LOS), 18 normal elderly controls and 12 patients with moderate cognitive impairment due to Alzheimer's disease (AD) who had no non-cognitive symptoms. While both patient groups has smaller volumes of several medial temporal regions (e.g. entorhinal cortex, left hippocampus), schizophrenics had significantly smaller anterior superior temporal gyri (STG) than normal controls, but AD patients did not. We have previously demonstrated anterior STG volume to be reduced in early life onset schizophrenia.  相似文献   
90.
本组采用的扩大的椎板开窗术治疗腰椎间盘突出合并侧隐窝狭窄140例。结果全部优良,与适应症严格选择和手术损伤小有关。强调切除卡压神经根的侧隐窝后壁外侧,即上关节突的冠状面.不失其脊椎三柱系统的三角结构。俯卧位头低足高,可减少硬膜囊张力避免负损伤。切除棘突下椎板时,用神经拉勾代替神经剥离器易于分离黄韧带,用90度的椎板咬骨钳斜向棘突方向,可满意地切除该部份椎板黄韧带,并可刮切椎板内层。神经根周围滴入醋酸炎舒松A2-3ml,术后疼痛锐减。减压窗口置盖明胶海绵有其争议,作者实践体会放置害处不大,要求病人有“护腰”意识。  相似文献   
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