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61.
Cholesteryl ester transfer protein (CETP) greatly affects the metabolism of all lipoprotein classes including low-density lipoprotein (LDL) and high-density lipoprotein (HDL), both known to constitute powerful risk factors for coronary artery disease (CAD). We now report the successful first cloning and characterization of single-chain antibody fragments specific for CETP. A recombinant phage display library was generated using spleen mRNA isolated from BALB/c mice that had been immunized with highly purified CETP. Screening of the library yielded two single-chain antibody fragments with high affinity for CETP, termed 1CL8 and 1CL10, displaying respective KD values of 4.36 x 10(-9) M and 4.64 x 10(-9) M as determined by affinity sensor technology. Amino acid sequence comparison indicated the complementarity-determining regions of the respective heavy chains to be responsible for CETP high affinity binding. Fragment 1CL8 was successfully employed in clinical chemical quantification systems that uncovered an association in humans between plasma CETP concentration and total body fat mass (r=0.50, p<0.002). Because of the demonstrated superb CETP capturing capacity, combined with high binding affinity to CETP, ready access and unlimited supply, 1CL8 and 1CL10 are expected to prove powerful tools for studies on the role of CETP in atherogenesis.  相似文献   
62.
Endoscopic submucosal dissection (ESD) for colorectal cancer is not widely accepted because of its technical difficulty and the risk of perforation. In addition, the risk of peritonitis cannot be completely eliminated even if a perforation is closed successfully. Reported here are two cases of early colon cancer in which the patients sustained iatrogenic perforations of the ascending colon during conventional endoscopic mucosal resection and of the sigmoid colon during ESD, respectively, requiring abdominal decompression with an 18 G Medicut needle. Both of these perforations were successfully treated by endoscopic clipping. In conclusion, conservative medical management may be possible in patients who have undergone successful closure of colonic perforations using endoscopic clipping. In order to perform immediate endoscopic closure, abdominal decompression has been useful to decrease patient discomfort and colonic lumen collapse. Now, CO2 insufflation is being used effectively for the prevention of pneumoperitoneum.  相似文献   
63.
PURPOSE: The purpose of this study was to determine if intrathecal landiolol, a beta1-blocker, can modulate formalin-induced nociception and spinal c-Fos expression in mice, in the absence of anesthesia. METHODS: Thirty-two mice were randomly assigned to one of four groups: the control group (n = 8) received intrathecal normal saline 10 microL, while the other three groups (n = 8 for each) received intrathecal landiolol at escalating doses of 250 microg.kg(-1), 500 microg.kg(-1) and 750 microg.kg(-1) respectively, immediately after induction of anesthesia with isoflurane. After awakening, inflammatory pain was induced by 10 microL of 5% formalin solution injected into the dorsal surface of the right hind paw. The nociceptive behaviours including licking, biting and lifting of the injected paw were cumulatively recorded as seconds of behaviours/min during phase I (0-10 min) and phase II (10-45 min). The c-Fos protein expressions in the spinal dorsal horn were detected with immunohistochemical techniques in the control and landiolol 750 microg.kg(-1) groups. RESULTS: Compared to the control group, intrathecal injection of landiolol 750 microg.kg(-1) significantly decreased pain-related behaviours in phase I, while intrathecal landiolol 250 microg.kg(-1), 500 microg.kg(-1) and 750 microg.kg(-1) significantly decreased pain-related behaviours in phase II during the formalin test. The numbers of c-Fos immunoreactive nuclei in the L5 spinal dorsal horn were significantly lower in the landiolol 750 microg.kg(-1) group compared to the control group (landiolol 750 microg.kg(-1) 2.4 +/- 1.1 vs control 9.2 +/- 3.9; P < 0.01). CONCLUSION: The present study indicates that intrathecally administered landiolol produces significant antinociceptive effects in the formalin test. Although further studies exploring the detailed mechanism are needed, these data suggest a potential role of beta1-adrenoreceptors in spinal nociceptive processing.  相似文献   
64.
65.
We examined cellular membrane fatty acid composition and insulin sensitivity in patients with mild essential hypertension and hyperlipidemia, and investigated whether bezafibrate, a lipid-lowering drug, could improve elevated blood pressure and insulin sensitivity in these subjects by ameliorating cellular membrane fatty acid composition. Twenty-seven subjects were recruited. Twelve men with mild essential hypertension [systolic blood pressure (SBP) between 140 mmHg and 160 mmHg] and hypertriglyceridemia (plasma triglyceride concentration over 150 mg/dl) were designated the HL group. Fifteen men with mild essential hypertension and normotriglyceridemia (plasma triglyceride concentration below 150 mg/dl) were designated the NL group. Subjects in the HL group were given bezafibrate 400 mg/dl and those in the NL group were given placebo for 3 months. Bezafibrate significantly reduced SBP (140 +/- 2.6 to 131.8 +/- 2.6 mmHg, mean +/- SEM), diastolic blood pressure (DBP) (87.8 +/- 2.0 to 82.8 +/- 2.6 mmHg), fasting plasma triglyceride concentration (225.5 +/- 23.5 to 102.9 +/- 10.9 mg/dl), fasting plasma insulin concentration (9.6 +/- 0.8 to 7.1 +/- 0.8 microU/ml), and homeostasis model assessment scores (HOMA-R, 2.4 +/- 0.2 to 1.7 +/- 0.2), and significantly improved the insulin sensitivity index (56.0 +/- 3.0 to 70.7 +/- 4.8 mg x l2/mmol x mU x min) in the HL group. Regarding erythrocyte membrane fatty acid composition, bezafibrate reduced the percentages of saturated fatty acids (SFA) and increased the percentage of polyunsaturated fatty acids (PUFA). Plasma triglyceride concentrations were positively correlated with HOMA-R (r = 0.50, p < 0.01) and SFA (r = 0.39, p < 0.05), and negatively correlated with PUFA (r = -0.45, p < 0.05) before administration of placebo or bezafibrate. In conclusion, an improvement of hyperlipidemia by bezafibrate may be attributed to reduction of blood pressure and amelioration of insulin sensitivity. Abnormalities in membrane lipid composition may play an important role in these metabolic disorders.  相似文献   
66.
67.
Calcifying odontogenic cyst (COC) has shown to be of extensive diversity in its clinical and histopathological features, as well as in its biological behavior. In this report, a rare case is described of ameloblastoma ex COC (dentinogenic ghost cell tumor) and the relevant literature is briefly reviewed.  相似文献   
68.
69.
The excitatory responses of deflationary slowly adapting pulmonary stretch receptor (SAR) activity to lung deflation ranging from approximately -15 to -25 cm of H(2)O for approximately 5 s were examined before and after administration of flecainide, a Na(+) channel blocker, and K(+) channel blockers, such as 4-aminopyridine (4-AP) and tetraethylammonium (TEA). The experiments were performed in anesthetized, artificially ventilated rats after unilateral vagotomy. The deflationary SARs increased their activity during lung deflation and its effect became more pronounced by increasing the degree of negative pressure. During lung deflation the average values for the deflationary SAR adaptation index (AI) were below 40%. Intravenous administration of veratridine (50 microg/kg), an Na(+) channel opener, stimulated deflationary SAR activity: one maintained excitatory activity mainly during deflation and the other receptors showed a tonic discharge during both deflation and inflation. Despite the difference in deflationary SAR firing patterns after veratridine administration, flecainide treatment (6.0 mg/kg) blocked veratridine-induced deflationary SAR stimulation and also caused strong inhibition of the excitatory responses of deflationary SARs to lung deflation. Under these conditions, the average values for deflationary SAR AI were over 90%. The responses of deflationary SARs and deflationary SAR AI to lung deflation were not significantly altered by pretreatment with either 4-AP (0.7 and 2.0 mg/kg) or TEA (2.0 and 6.0 mg/kg). These results suggest that the excitatory effect of lung deflation on deflationary SAR activity is mediated by the activation of flecainide-sensitive Na(+) channels on the nerve terminals of deflationary SARs.  相似文献   
70.
We analyzed the CT images (in vivo) of 5 lobes (right middle lobe, 1; left lower lobe, 1; right lower lobe, 3) with panacinar emphysema (PAE) obtained at autopsy or thoracotomy for solitary lung tumor. The lobes were inflation-fixed by the method of Heitzman and sliced axially for a CT-pathologic correlative study. One lobe with mild PAE had normal appearance on CT; however, the other four lobes with PAE demonstrated low-attenuation areas (LAAs) of various shapes and sizes on CT. LAAs were locally distributed on CT slices in one lobe, dominant in the inner zones in two lobes, and diffuse in one lobe. Relatively normal to diminished vasculature was observed within the LAAs of four lobes. These CT findings differed significantly from those of centriacinar emphysema (CAE) as reported in other studies. We conclude that CT is useful in the clinical diagnosis of PAE and its differentiation from CAE.  相似文献   
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