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991.
中风病急性期证候演变规律的研究   总被引:26,自引:1,他引:26  
应用证候量化诊断的方法,对733例经CT或MRT确诊的中风病始发态患者,进行了为期4周的7次追踪调查.结果显示:(1)证候的得分均值、发生概率、组合形式、组合形态是动态变化的随时间序列呈现一定的规律性,并受到病变性质的影响;(2)求得了不同时间序列6个基本证候的逐阶转移概率和高阶转移概率.研究结果对深入认识中风病急性期病因病机,判断病势转归,指导辨证治疗,防止向恶转变,具有重要的理论意义和应用价值.  相似文献   
992.
A term small-for-date male baby with features of Russell-Silver syndrome is discussed. Though no family history is usually obtained this baby had an elder sibling with exactly similar features.  相似文献   
993.
PURPOSE: The use of electrophysiologic studies (EPS) for the localization of accessory atrioventricular connections in Wolff-Parkinson-White syndrome (WPW) requires accurate evaluation of the site of bypass tract insertion. Doppler myocardial imaging (DMI) is a new ultrasound technique that allows the detection of abnormal and early regional myocardial depolarization. The purpose of this study was to identify an abnormal pathway site in WPW patients. METHODS: Twenty-one patients with ventricular preexcitation were studied by DMI. Two-dimensional color DMI, velocity maps, acceleration maps, and pulsed-wave applications were used. A subsequent diagnostic EPS was performed. The results of EPS were taken as the gold standard diagnostic procedure. Radiofrequency catheter ablation therapy was then performed on all patients. RESULTS: The anomalous pathway was detected by DMI in 16 (76%) of 21 patients (9 [90%] of 10 with left pathways and 7 [64%] of 11 with right pathways), with respect to results of the EPS. Pathway detection was better with pulsed-wave DMI (76%) with its higher temporal resolution as compared with M-mode velocity map (57%) and acceleration map (47%). In most of the patients with successful radiofrequency ablation, an immediate resolution of the abnormal ventricular depolarization occurred and was detectable by DMI. CONCLUSIONS: Our findings demonstrate the feasibility of DMI to assess the early ventricular contraction associated with atrioventricular accessory pathways. Therefore, DMI appears to be a clinically useful adjunct to noninvasive evaluation of abnormal myocardial depolarization in WPW and to evaluate the results after radiofrequency ablation, even though its accuracy is considerably better for left-sided accessory pathways than for right-sided ones.  相似文献   
994.
Chemokines as novel therapeutic targets in inflammatory diseases   总被引:5,自引:0,他引:5  
Chemokines and their receptors are a large family of inflammatory molecules responsible for a number of biological functions, including the accumulation of leukocytes at tissue sites. Over the past 10 years, a number of studies have indicated a role for chemokines and chemokine receptors in the pathophysiology of several inflammatory diseases, examples of which are multiple sclerosis, atherosclerosis, rheumatoid arthritis, and gastrointestinal diseases including hepatic disease. For this reason, it is not surprising that modulation of their pharmacology could be a prime target for drug discovery. This commentary provides a brief synopsis of our current knowledge of the role of chemokines and their receptors in the inflammatory process, and highlights the pros and possibly cons of chemokine and chemokine receptor antagonism in the therapeutic approach to several inflammatory diseases.  相似文献   
995.
巯基乙酸经呼吸道染毒对小鼠免疫功能的影响   总被引:4,自引:0,他引:4       下载免费PDF全文
目的 研究巯基乙酸经呼吸道染毒对小鼠免疫功能的影响。方法 选择 1 8~ 2 2g昆明种小鼠 ,1 0只 /组 ,雌雄各半 ,以巯基乙酸 0 4,0 8,4 0mg/L经呼吸道静式吸入染毒 ,7天后进行体液免疫、细胞免疫、非特异性免疫及免疫器官脏器系数测试。结果 实验组脾脏的脏器系数均明显低于对照组 (P <0 0 1 ) ,抗体形成细胞 (plague formingcell,PFC)数、巨噬细胞吞噬百分数及吞噬指数均低于对照组 (P <0 0 5,P <0 0 1 )。结论 巯基乙酸经呼吸道吸入染毒对小鼠的体液免疫和非特异性免疫功能可能有抑制作用。  相似文献   
996.
997.
Imidazoacridinones (IA) are a class of antitumor agents which includes C-1311, an interesting drug in clinical trials. This study investigated the mechanism of IA binding to DNA for a series of 13 analogs that differ in their cytotoxic potency. Using C-1311 as a model compound, crystallographic, spectroscopic and biochemical techniques were employed to characterize drug-DNA interactions. X-ray crystallographic analysis revealed a planar structure of imidazoacridinone core that is capable of intercalative DNA binding. Accordingly, C-1311 binding to DNA followed 'classical' pattern observed for intercalation, as proved by the DNA topoisomerase I-unwinding experiments, with relatively weak binding affinity (K(i)=1.2 x 10(5)M(-1)), and the binding site size of 2.4 bp. Other IA also bound to DNA with the binding affinity in the range of 10(5)M(-1) and binding site size of 2-3 bp, suggesting a prevalence of the intercalative mechanism, similar to C-1311. Considerable DNA binding affinity was displayed by all the highly cytotoxic derivatives. However, none of the analyzed drug-DNA binding parameters was significantly correlated with IA biological activities such as cell growth, DNA and RNA synthesis inhibition, or tumor growth inhibition, which suggests that the IA ability to non-covalently bind to DNA is not crucial for their biological activity. These results show that the ability to intercalate into DNA is a prominent attribute of IA, although factors other than intercalative binding seem to be required for the biological activities of IA drugs.  相似文献   
998.
McLeod Syndrome (MLS) is a rare X-linked disorder characterized by haemopoietic abnormalities and late-onset neurological and muscular defects. The McLeod blood group phenotype is typically associated with erythrocyte acanthocytosis, absence of the Kx antigen and reduced expression of Kell system antigens. MLS is caused by hemizygosity for mutations in the XK gene. We describe a patient with MLS who first showed symptoms in 1989 (aged 51 years). As the disease progressed, the patient developed a slight dementia, aggressive behaviour and choreatic movements. A cardiomyopathy was also diagnosed. An electroneuromyography showed neuropathic and myopathic changes. Liver enzymes were elevated and a blood smear showed acanthocytes. MLS was confirmed by serological analysis of the Kell antigens. Analysis of red blood cells by flow cytometry revealed the patient and his grandson to have reduced Kell antigen expression. The patient's daughters had two populations of red cells, consistent with them being heterozygous for an XK0 allele. The molecular basis of MLS in this family is a novel mutation consisting of a 7453-bp deletion that includes exon 2 of the XK gene. This confirms that the patient's 7-year-old grandson, who is currently asymptomatic, also has the XK0 allele and is therefore likely to develop MLS.  相似文献   
999.
Lower limb compartment syndrome is an unusual but severe complication of prolonged surgery more than four hours in lithotomy position. It is usually a consequence of hypoperfusion of the lower extremities and muscle necrosis may occur. Several risk factors are pointed out: trendelenburg, the hardness of operating table, hypothermia, control hypotension, occlusion of arterial blood flow of the lower extremity, arteritis (and smoking), diabetes, obesity, arterial hypertension, myopathy and an important muscle mass. The symptoms are postoperative pain with neurological signs. A rapid diagnosis and aggressive management (i.e. resuscitation and aponevrotomy) is recommended. Neurological sequelae are sometimes invalidating. Reporting a case of bilateral syndrome, we reviewed the literature and describe the present diagnosis and therapeutic management as well as prevention modalities of this iatrogenic complication.  相似文献   
1000.
Many studies are done in small isolated populations and populations where marriages between relatives are encouraged. In this paper, we point out some problems with applying the maximum lod score (MLS) method (Risch, [1990] Am. J. Hum. Genet. 46:242-253) in these populations where relationships exist between the two parents of the affected sib-pairs. Characterizing the parental relationships by the kinship coefficient between the parents (f), the maternal inbreeding coefficient (alpha(m), and the paternal inbreeding coefficient (alpha(p)), we explored the relationship between the identity by descent (IBD) vector expected under the null hypothesis of no linkage and these quantities. We find that the expected IBD vector is no longer (0.25, 0.5, 0.25) when f, alpha(m), and alpha(p) differ from zero. In addition, the expected IBD vector does not always follow the triangle constraints recommended by Holmans ([1993] Am. J. Hum. Genet. 52:362-374). So the classically used MLS statistic needs to be adapted to the presence of parental relationships. We modified the software GENEHUNTER (Kruglyak et al. [1996] Am. J. Hum. Genet. 58: 1347-1363) to do so. Indeed, the current version of the software does not compute the likelihood properly under the null hypothesis. We studied the adapted statistic by simulating data on three different family structures: (1) parents are double first cousins (f=0.125, alpha(m)=alpha(p)=0), (2) each parent is the offspring of first cousins (f=0, alpha(m)=alpha(p)=0.0625), and (3) parents are related as in the pedigree from Goddard et al. ([1996] Am. J. Hum. Genet. 58:1286-1302) (f=0.109, alpha(m)=alpha(p)=0.0625). The appropriate threshold needs to be derived for each case in order to get the correct type I error. And using the classical statistic in the presence of both parental kinship and parental inbreeding almost always leads to false conclusions.  相似文献   
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