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991.
OBJECTIVE. We describe the CT and pathologic features of malignant papillary neoplasms of the intrahepatic bile ducts in 15 patients. CONCLUSION. CT is a useful technique for revealing intraductal lesions, although the findings are nonspecific and variable. When intraductal masses or nodules are seen with localized dilatation of the intrahepatic bile ducts on CT scans, malignant papillary neoplasms of the intrahepatic bile ducts should be included in the differential diagnosis.  相似文献   
992.
Experiments on outbred albino rats showed that administration of acetylcholine and aceclidine in a dose of 0.1 LD50 for 3 days and of dimethyl dichlorovinyl phosphate (organophosphorus compound) in a single dose of 0.05 LD50 stimulated the function of Th1 and Th2 lymphocytes and cytokine production by these cells. Dimethyl dichlorovinyl phosphate in a single dose of 0.5 LD50 produced an opposite effect. Acetylcholine and aceclidine stimulated activity of acetylcholinesterase in T cells, while dimethyl dichlorovinyl phosphate in a single dose of 0.5 LD50 inhibited it. During acute intoxication, the organophosphorus compound, depending on the dose, can stimulate (acetylcholine effect) and inhibit the immune reactions (acetylcholinesterase inhibition of T cells).  相似文献   
993.
Cell deformability is an important biomarker which can be used to distinguish between healthy and diseased cells. In this study, microfluidics is used to probe the biorheological behaviour of breast cancer cells in an attempt to develop a method to distinguish between non-malignant and malignant cells. A microfabricated fluidic channel design consisting of a straight channel and two reservoirs was used to study the biorheological behaviour of benign breast epithelial cells (MCF-10A) and non-metastatic tumor breast cells (MCF-7). Quantitative parameters such as entry time (time taken for the cell to squeeze into the microchannel) and transit velocity (speed of the cell flowing through the microchannel) were defined and measured from these studies. Our results demonstrated that a simple microfluidic device can be used to distinguish the difference in stiffness between benign and cancerous breast cells. This work lays the foundation for the development of potential microfluidic devices which can subsequently be used in the detection of cancer cells. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
994.
We report a rare case of giant mesenteric lipoma presenting with colicky abdominal pain. A 29-yr-old woman underwent laparoscopic resection for a giant mesenteric lipoma causing compression of the ileal loop. The resected ileal segment was encased by a giant fatty tissue, and normal mucosal fold patterns of the resected ileum were effaced by the mass. Microscopically, the mass was characterized by homogenous mature adipose tissue without cellular atypia, which was compatible with the diagnosis of a mesenteric lipoma. Despite the benign nature of this tumor, total excision with or without the affected intestinal loop should be considered if intestinal symptoms such as abdominal pain are present.  相似文献   
995.
996.
997.
Acute phencyclidine (PCP) administration mimics some aspects of schizophrenia in rats, such as behavioral alterations, increased dopaminergic activity and prefrontal cortex dysfunction. In this study, we used single‐voxel 1H‐MRS to investigate neurochemical changes in rat prefrontal cortex in vivo before and after an acute injection of PCP. A short‐echo time sequence (STEAM) was used to acquire spectra in a 32‐µL voxel positioned in the prefrontal cortex area of 12 rats anesthetized with isoflurane. Data were acquired for 30 min before and for 140 min after a bolus of PCP (10 mg/kg, n = 6) or saline (n = 6). Metabolites were quantified with the LCModel. Time courses for 14 metabolites were obtained with a temporal resolution of 10 min. The glutamine/glutamate ratio was significantly increased after PCP injection (p < 0.0001, pre‐ vs. post‐injection), while the total concentration of these two metabolites remained constant. Glucose was transiently increased (+70%) while lactate decreased after the injection (both p < 0.0001). Lactate, but not glucose and glutamine, returned to baseline levels after 140 min. These results show that an acute injection of PCP leads to changes in glutamate and glutamine concentrations, similar to what has been observed in schizophrenic patients, and after ketamine administration in humans. MRS studies of this pharmacological rat model may be useful for assessing the effects of potential anti‐psychotic drugs in vivo. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
998.
We present two cases of Wiskott-Aldrich syndrome (WAS), in which nonsense mutations in the WASP gene were corrected phenotypically as well as genotypically by unrelated cord blood stem cell transplantation (CBSCT). Two male patients were diagnosed with WAS at the age of 5-month and 3-month and each received unrelated CBSCT at 16-month and 20-month of age, respectively. The infused cord blood (CB) units had 4/6 and 5/6 HLA matches and the infusion doses of total nucleated cells (TNC) and CD34+ cells were 6.24×107/kg and 5.08×107/kg for TNC and 1.33×105/kg and 4.8×105/kg for CD34+ cells, for UPN1 and UPN2, respectively. Complete donor cell chimerism was documented by variable number tandem repeat (VNTR) with neutrophil engraftment on days 31 and 13 and platelets on days 58 and 50, respectively. Immunologic reconstitution demonstrated that CBSCT resulted in consistent and stable T-, B-, and NK-cell development. Flow cytometric analysis for immunologic markers and sequence analysis of the WASP gene mutation revealed a normal pattern after CBSCT. These cases demonstrate that CBs can be an important source of stem cells for the phenotypical and genotypical correction of genetic diseases such as WAS.  相似文献   
999.
Heterotopic gastric mucosa tissue is also called gastric choristoma, and this type of lesion can be found anywhere in the alimentary tract. However, gastric choristoma in the pharynx is very rare; only 10 cases of pharyngeal gastric choristoma have been reported in the English medical literature. A 32-yr-old woman was referred to our institution for the evaluation of a large mass that originated from the posterior wall of the oropharynx. The mass did not cause any symptoms except for the occasional sensation of a foreign body. Gadolinium-enhanced T1 weighted imaging showed a 5 cm-sized mass with central enhancement and hypointense portions, yet the radiological diagnosis was not clear. Transoral mass excision was performed with using electrocautery for making the diagnosis and for treating the mass. The microscopic analysis revealed gastric choristoma.  相似文献   
1000.
Experiments on outbred albino rats showed that subacute poisoning with tetrachloromethane in a total dose of 1.0 LD50 appreciably decreased blood concentrations of cytokines (IFN-γ, IL-2, IL-4, IL-6, IL-10), reduced the IFN-γ/IL-4 ratio in comparison with the control, and suppressed the immune reactions, which attests to greater damage to Th1 compared to Th2 lymphocytes. Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 147, No. 1, pp. 55-57, January, 2009  相似文献   
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