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1.
Cerebral blood flow (CBF) and other physiological variables were measured repeatedly for up to 10 days after severe head injury in 102 patients, and CBF levels were related to outcome. Twenty five of the patients had a reduced CBF [mean (SD) 0.29 (0.05) ml/g/min]; 47 had a normal CBF, (0.41 (0.10) ml/g/min); and 30 had a raised CBF (0.62 (0.14) ml/g/min). Cerebral arteriovenous oxygen differences were inversely related to CBF and averaged 2.1 (0.7) mumol/ml in the group with reduced CBF, 1.9 (0.5) mumol/ml in the group with normal CBF, and 1.6 (0.4) mumol/ml in the group with raised CBF. Patients with a reduced CBF had a poorer outcome than patients with a normal or raised CBF. Mortality was highest in patients with a reduced CBF, and was 32% at three months after injury, whereas only 21% of the patients with a normal CBF and 20% of the patients with a raised CBF died. There were no differences in the type of injury, initial score on the Glasgow Coma Scale, mean intracranial pressure (ICP), highest ICP, or the amount of medical treatment required to keep the ICP less than 20 mm Hg in each group. Systemic factors did not significantly contribute to the differences in CBF among the three groups. A logistic regression model of the effect of CBF on neurological outcome was developed. When adjusted for variables which were found to be significant confounders, including age, initial Glasgow Coma Score, haemoglobin concentration, cerebral perfusion pressure and cerebral metabolic rate of oxygen, a reduced CBF remained significantly associated with an unfavourable neurological outcome.  相似文献   
2.
SARS-CoV isa newly identified coronavirus that causes severe acute respiratory syndrome (SARS). Currently, there is no effective method available for prophylaxis and treatment of SARS-CoVinfections. In the present study, the influence of small interfering RNA (siRNA) on SARS-CoV nucleocapsid (N) protein expression was detected in cultured cells and mouse muscles. Four siRNA expression cassettes driven by mouse U6 promoter targeting SARS-CoV N gene were prepared, and their inhibitory effects on expression of N and enhanced green fluorescence protein (EGFP) fusion protein were observed.  相似文献   
3.
黑柴胡中新三萜皂甙的结构鉴定   总被引:3,自引:0,他引:3  
从黑柴胡(Bupleurum smithii Wolff)根中分离出10个化合物,均为首次由该植物中获得。其中二个新三萜皂甙,即柴胡皂甙k和l(saikosaponin k and l),其结构经紫外、红外、核磁共振氢谱,碳谱和质谱等波谱测定和解析,分别确定为3β,16β,23,28-四羟基齐墩果烷-11,13(18)-二烯-3-O-β-D-吡喃木糖基-(1→2)-β-D-吡喃葡萄糖基-(1→3)-β-D-吡喃呋糖甙和3β,16α,23,28,30-五羟基齐墩果烷-11,13(18)-二烯-3-O-β-D-吡喃葡萄糖基-(1→3)-β-D-吡喃呋糖甙。  相似文献   
4.
This retrospective study of formalin-fixed infiltrating breast cancer specimens compared manual immunohistochemical assay with a new image analyzer-assisted immunohistochemical quantitation method, using fluorescence in situ hybridization assay (FISH) as the standard. Following the manual immunohistochemical assay, 189 cases, including most manual immunohistochemically positive and some random negative cases, were analyzed by FISH assay for Her-2/neu gene amplification and by the Automated Cellular Imaging System (ACIS) for immunohistochemical staining. Using the FISH standard, the ACIS immunohistochemical assay attained a higher concordance rate and sensitivity than the manual immunohistochemical assay (91.0% and 88% vs 85.7% and 71%, respectively), with only a slight decrease in specificity (93% vs 96%, respectively). In particular, the ACIS immunohistochemical assay resulted in a higher correlation with the FISH assay in the manual immunohistochemical assay 2+ cases. The ACIS immunohistochemical assay achieved higher accuracy than the manual method according to receiver operating characteristic curve analysis. The ACIS method represents a substantial improvement over the manual method for objective evaluation of the HER-2/neu status.  相似文献   
5.
Our previous studies showed that glioblastomas express increased urokinase-type plasminogen activator receptors (uPARs) in comparison to low-grade gliomas (Yamamoto et al., Cancer Res., 54, 5016-5020, 1994). To explore whether downregulation of uPAR inhibits tumor formation and invasiveness, a human glioblastoma cell line was transfected with a cDNA construct corresponding to 300 bp of the human uPAR's 5¢ end in an antisense orientation, resulting in a reduced number of uPA receptors. Co-culture studies with tumor spheroids and fetal rat brain aggregates showed that antisense SNB19-AS1 cells expressing reduced uPAR failed to invade fetal rat brain aggregates. Intracerebral injection of SNB19-AS1 stable transfectants failed to form tumors and were negative for uPAR expression in nude mice. Thus uPAR appears in this model to be essential for tumorigenicity and invasion of glioblastomas in vivo.  相似文献   
6.
PURPOSE: The purpose of this study was to profile gene expression changes in colorectal tumors to identify new targets and strategies for the management of this disease. EXPERIMENTAL DESIGN: cDNA microarray analysis was used to detect differences in gene expression between normal tissue and colon tumors and polyps isolated from 20 patients. To identify genes that are important in regulating the growth properties of colorectal cancer, RNA interference (RNAi) was used to disrupt expression of several of the overexpressed genes in a colon tumor cell line, HCT116, which showed similar patterns of gene expression as many of the patient tumors. RESULTS: Expression changes of > or =2-fold in approximately one-third of the patients were consistently observed for 2632 of a total of 9592 genes (574 up-regulated genes and 2058 down-regulated genes). Subsequent analysis of 13 genes by quantitative real-time PCR confirmed the reliability of this analysis. RNAi-mediated disruption of the expression of one of these genes, survivin, a potent inhibitor of apoptosis, severely reduced tumor growth both in vitro and in an in vivo xenograft model. CONCLUSIONS: The combined use of microarray analysis and RNAi provides an excellent system to define the role of specific genes that are up-regulated in cancer lead to the increased in vitro and in vivo growth of colon tumors.  相似文献   
7.
几种中西药抗人实验模拟运动病效果观察   总被引:1,自引:0,他引:1  
目的 :选用中药“治晕灵”的主要成分生姜、明天麻等六味草药煎成汤剂、或半量汤剂配西药脑益嗪、山莨菪碱各1 4临床常用量配成复方中西药制剂 ,与目前常用抗晕药晕海宁等中、西药的药效进行比较 ,看中药制剂或中西药复方制剂是否具有较好的抗运动病效果。方法 :选 7名敏感被试者 (女性 ,19~ 2 1岁 ) ,用旋转刺激诱发运动病至出现恶心。按拉丁方设计 ,与安慰剂 (淀粉 10 0mg)及晕海宁 (5 0mg)进行对比 ,分别观察了生姜合剂 (30ml)、晕可平 (30ml)、山莨菪碱 (10mg)、脑益嗪 (2 5mg)及上述复方中西药制剂口服后的运动病耐力。结果 :与安慰剂比较 ,晕海宁、山莨菪碱、脑益嗪、晕可平、生姜合剂、复方中西药制剂分别使运动病耐力提高 5 .4%、7.5 %、5 .9%、7.4%、32 .3 %、2 0 .4% ;生姜合剂效果较优 ,除口服时有辛辣味外 ,无明显的副作用。复方中西药制剂各成分未显示协同作用 ,而只是简单的作用相加。结论 :生姜合剂具有较好的抗运动病作用  相似文献   
8.
The nucleocapsid (N) protein of SARS-coronavirus (SARS-CoV) is the key protein for the formation of the helical nucleocapsid during virion assembly. This protein is believed to be more conserved than other proteins of the virus, such as spike and membrane glycoprotein. In this study, the N protein of SARS-CoV was expressed in Escherichia coli DHSalpha and identified with pooled sera from patients in the convalescence phase of SARS. A plasmid pCI-N, encoding the full-length N gene of SARS-CoV, was constructed. Expression of the N protein was observed in COS1 cells following transfection with pCI-N. The immune responses induced by intramuscular immunization with pCI-N were evaluated in a murine model. Serum anti-N immunoglobutins and splenocytes proliferative responses against N protein were observed in immunized BALB/c mice. The major immunoglobulin G subclass recognizing N protein was immunoglobulin G2a, and stimulated splenocytes secreted high levels of gamma interferon and IL-2 in response to N protein. More importantly, the immunized mice produced strong delayed-type hypersensitivity (DTH) and CD^8+ CTL responses to N protein.  相似文献   
9.
Herein, we present a case of asymptomatic isolated cardiac cystic echinococcosis localized entirely to the inter‐atrial septum in a pregnant woman. The patient underwent successful surgery. Cardiac cystic echinococcosis is rarely seen in pregnancy. A high index of suspicion is necessary for the diagnosis of a cardiac cyst hydatid. The treatment of cardiac cyst hydatid is surgical and should not be delayed during pregnancy. Early surgery might prevent septic embolization and cardiac life‐threatening complications and save the lives of both mother and baby as in the present case.  相似文献   
10.
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