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991.
Neonatal hypoxic-ischemic (HI) encephalopathy can lead to severe brain damage, and is a common cause of neurological handicaps in adulthood. HI can be resolved by the administration of an antioxidant such as 3-methyl-1-phenyl-2-pyrazolin-5-one (MCI-186). In the present study, we performed comprehensive gene expression and gene network analyses using a DNA microarray to elucidate the molecular events responsible for the selective vulnerability of neurons in neonatal HI brain insult and to examine the underlying mechanisms of the effect of MCI-186 on the pathophysiological events in this condition. We used the modified Levine method (Rice model), which has been widely used as an animal model of this condition. A large difference in gene expression was observed between the Rice model and the control group. Up- and downregulated genes after the HI brain insult were mainly related to immune responses and cell death, and neuronal activity, respectively. The effect of MCI-186 administration on gene expression was much less than and contrary to that of the HI brain insult, reflecting the protective effect of MCI-186 in HI brain insult.  相似文献   
992.
993.
BACKGROUND: Ischemia-reperfusion injury of the lung frequently occurs after cardiopulmonary bypass, after pulmonary thromboendarterectomy, and especially after lung transplantation. Heparin is known to be protective in ischemia-reperfusion injury, but the risk for bleeding disorders may restrict its use in a variety of diseased conditions. Therefore, we tested the efficiency of nonanticoagulant N-acetyl (NA) heparin to protect from postischemic reperfusion injury of the lung. METHODS: Pentobarbital-anesthetized, mechanically ventilated Lewis rats were heparinized (100 IU/kg) before insertion of catheters. Additionally, animals received either heparin (200 IU/kg; n = 7), NA heparin (1.1 mg/kg; n = 7), or saline (control, n = 7) before ischemia. After normothermic ischemia for 50 minutes, the left lung was reperfused for 120 minutes, or until the death of the animal. The nonischemic right lung was excluded after 10 minutes of reperfusion. RESULTS: Survival rate at 120 minutes of reperfusion was 7 of 7 and 6 of 7 in the heparin and the NA-heparin group, but 0 in 7 in the control group (p < 0.01). At 30 minutes of reperfusion, PaO2, blood flow through the ascending aorta and mean systemic blood pressure were also significantly higher in the heparin and the NA-heparin group when compared with the control group (p < 0.05). Pulmonary vascular resistance was significantly lower in the heparin and the NA-heparin groups, and histologic examination of the lungs from these groups confirmed reperfusion of nutritive alveolar capillaries by the presence of red blood cells. Lack of red blood cells in the alveolar capillaries of lung specimens from the control group indicated failure of capillary reperfusion. CONCLUSIONS: Heparin and NA heparin exert similar protection against capillary no-reflow after normothermic ischemia of the lung. This implies that the protective effect of heparin is mediated by properties different from its anticoagulant activity. Thus the nonanticoagulant N-acetyl heparin may pose a safe new therapeutic approach in lung ischemia-reperfusion injury without increasing the risk of hemorrhagic complications.  相似文献   
994.
The distribution of spinal anesthesia is affected by the density and viscosity of the local anesthetic solution that, in turn, may be influenced by the temperature of the injectate. Our hypothesis in the present study was that the temperature of the injectate influences its distribution into the subarachnoid space. We measured the density and viscosity of hyperbaric 0.5% bupivacaine at 25 degrees C and 37 degrees C and tested the onset and extent of spinal anesthesia achieved by these solutions in 36 patients. The densities of the two solutions were similar (mean [sd]): 25 degrees C, 1.028 [0.000], versus 37 degrees C, 1.028 [0.000] (g/mL), but the viscosity was more at 25 degrees C than at 37 degrees C (0.01116 [0.00003] versus 0.00843 [0.00002] g x cm(-1) x s(-1); P < 0.001). The maximum cephalad extent of loss of pinprick sensation was significantly higher with 37 degrees C (T2 with 37 degrees C versus T5 with 25 degrees C; P < 0.001), but the time to achieve peak block height was similar. In conclusion, we showed a consistent, but modest, increase in the cephalad level of spinal anesthesia by warming hyperbaric bupivacaine 0.5% from 25 degrees C to 37 degrees C. Viscosity was reduced in the warmed solution, but it is unclear if this or other factors led to the difference in spinal anesthetic level.  相似文献   
995.
Primary retroperitoneal neoplasms are a rare but diverse group of benign and malignant tumors that arise within the retroperitoneal space but outside the major organs in this space. Although computed tomography and magnetic resonance imaging can demonstrate important characteristics of these tumors, diagnosis is often challenging for radiologists. Diagnostic challenges include precise localization of the lesion, determination of the extent of invasion, and characterization of the specific pathologic type. The first step is to determine whether the tumor is located within the retroperitoneal space. Displacement of normal anatomic structures of the retroperitoneum is helpful in this regard. For tumors that are located within the retroperitoneum, the next step is to identify the organ of origin. Specific signs, including the "beak sign," the "embedded organ sign," and the "phantom (invisible) organ sign," are useful for this purpose. When there is no definite sign that suggests the organ of origin, the diagnosis of a primary retroperitoneal tumor becomes likely. Awareness of specific patterns of spread, specific tumor components, and tumor vascularity help in further narrowing the differential diagnosis. Attention to these diagnostic clues is essential in making an accurate radiologic diagnosis of primary retroperitoneal tumors and in obtaining clinically significant information. Copyright RSNA, 2003.  相似文献   
996.
A significant population of neurons in the vestibular nuclei projects to the cerebellum as mossy fibers (MFs) which are involved in the control and adaptation of posture, eye-head movements, and autonomic function. However, little is known about their axonal projection patterns. We studied the morphology of single axons of medial vestibular nucleus (MVN) neurons as well as those originating from primary afferents, by labeling with biotinylated dextran amine (BDA). MVN axons (n = 35) were classified into three types based on their major predominant termination patterns. The Cbm-type terminated only in the cerebellum (15 axons), whereas others terminated in the cerebellum and contralateral vestibular nuclei (cVN/Cbm-type, 13 axons), or in the cerebellum and ipsilateral vestibular nuclei (iVN/Cbm-type, 7 axons). Cbm- and cVN/Cbm-types mostly projected to the nodulus and uvula without any clear relationship with longitudinal stripes in these lobules. They were often bilateral, and sometimes sent branches to the flocculus and to other vermal lobules. Also, the iVN/Cbm-type projected mainly to the ipsilateral nodulus. Neurons of these types of axons showed different distribution within the MVN. The number of MF terminals of some vestibulocerebellar axons, iVN/Cbm-type axons in particular, and primary afferent axons were much smaller than observed in previously studied MF axons originating from major precerebellar nuclei and the spinal cord. The results demonstrated that a heterogeneous population of MVN neurons provided divergent MF inputs to the cerebellum. The cVN/Cbm- and iVN/Cbm-types indicate that some excitatory neuronal circuits within the vestibular nuclei supply their collaterals to the vestibulocerebellum as MFs.  相似文献   
997.
Malignant rhabdoid tumor (MRT) in the neck region is very rare. We report a case of MRT in a 60-year-old woman who had a history of papillary carcinoma of the thyroid gland 7 years previously. One year before admission, in 1995, thyroid carcinoma recurred, and the tumor contained a small undifferentiated region with rhabdoid features. The tumor in 1996 consisted of round to oval rhabdoid cells with abundant cytoplasm, and the growth pattern was diffuse and infiltrative, with no papillary structures. We therefore concluded that the lesion was MRT, transformed from papillary thyroid carcinoma.  相似文献   
998.
The transfer of the cationic forms of tryptamine and serotonin across the nitrobenzene (NB)/water (W) interface was studied by cyclic voltammetry. Well-defined voltammetric waves were observed within the potential window. The standard potentials of the transfer were determined from the midpoint potentials of the voltammograms. The transfer of the cationic form of tryptophan across the NB/W interface was also observed using an acidic aqueous solution.  相似文献   
999.
From March, 1984 to April, 1985, 70 cases of upper urinary tract calculi (73 renal units) were treated by percutaneous nephrolithotripsy or transurethro-ureteral lithotripsy, mainly utilizing ultrasonic lithotrite. While in the early period of treatment, two stage procedure of creation of nephrostomy tract and percutaneous nephrolithotripsy was performed for renal and upper or middle part of the ureteral calculi, one stage procedure, nephrostomy tract formation followed by ultrasonic nephrolithotripsy is commonly used in recent cases. During this period, conventional stone surgery was seen in 6 cases of pyelolithotomy and 2 of ureterolithotomy, while 52 cases of stone surgery were performed during the earlier period (from January, 1983 to February, 1984). Renal and upper or middle part of ureteral calculi were successfully removed in 49 out of 58 cases (84.5%). Most of the patients required 1 or 2 trials of percutaneous nephrolithotripsy. Middle or lower part of ureteral calculi were removed in transurethro-ureteral approach in 11 of the 12 cases. Hematuria and fever were most common complications after treatment and 3 patients required blood transfusion after 3 or 4 sessions of nephrolithotripsy. Percutaneous nephrolithotripsy and transurethro-ureteral lithotripsy are now widely used for treatment of upper urinary tract calculi, replacing the conventional surgical treatment. Moreover, very recently, extracorporeal shock wave lithotripsy is available in Japan. To the patients with renal calculi indicative of this treatment, both percutaneous nephrolithotripsy and extracorporeal shock wave lithotripsy are introduced and either way of treatment can be chosen by the patient himself.  相似文献   
1000.
A pan T-cell antigen with a molecular weight of 120 kilodaltons (kd) is recognized by a monoclonal antibody, Tp120, produced in our laboratories. Two hybrid clones reactive with this Tp120 antibody were established from the fusion between concanavalin A-stimulated human peripheral blood lymphocytes and hypoxanthine-guanine phosphoribosyltransferase-deficient mouse T cell leukemia, BW5147. These two clones were also positive with two other antibodies, 12.1 and T12, both of which detect 120kd pan T-cell antigen. Karyotype analysis showed that one clone retained human chromosomes 6, 7pq, and 11, and the other maintained chromosomes 11 and 21. As soon as both of these clones lost the chromosome 11, the expression of Tp120 became negative. The presence of human chromosome 11 was confirmed by the isozyme analysis of lactate dehydrogenase-A. The results indicated that the presence of chromosome 11 was essential for expression of 120kd pan T-cell antigen.  相似文献   
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