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51.
Five female patients and one male patient with solid and papillary epithelial neoplasms of the pancreas were examined with computed tomography (CT). The mean age of the patients was 27 years (range, 13-46 years). All cases showed well-encapsulated, round or lobulated masses consisting of both cystic and solid areas. Cystic portions showed CT numbers that suggested hemorrhagic necrosis. There were no internal septations within the masses. In three tumors located in the head of the pancreas, dilatation of the biliary tree was absent or minimal, although the masses were large. Two tumors contained calcifications. One tumor demonstrated metastatic deposits in liver and lymph nodes. Metastatic masses appeared similar to the primary pancreatic mass. Solid and papillary neoplasm of the pancreas should be the primary diagnostic consideration when characteristic CT findings are detected in a young female patient. 相似文献
52.
53.
A Tajiri T Okamoto T Otsu H Choi S Tang S Mizoguchi F Yanagi Y Sakanashi K Gotoh H Matsumura 《Masui. The Japanese journal of anesthesiology》1992,41(11):1788-1792
A 47-y-o man had been suffering from cardiac failure due to refractory ventricular tachycardia (VT) after myocardial infarction. He underwent resection of the left ventricular aneurysm and cryocoagulation of the arrhythmogenic foci. On the 2nd post-operative day, VT often recurred in spite of repeated cardioversion and drug therapy, and threatened his life, even under IABP. Therefore, a veno-arterial bypass route was made and extracorporeal lung and heart assist, ECLHA, was started with a heparin bonded Maxima lung on the following day. Even under ECLHA, VT continued to recur. Cryocoagulation of the VT foci was tried again, without immediate success. A record high dose of beta-blockers, given under the circulatory support by ECLHA, stopped VT on the following day. The patient was weaned from the ECLHA circuit 12 days after the first operation, then from IABP on the 14th day. During the 10 day course of surgeries and ECLHA, the patient had almost 100 defibrillations. But for ECLHA, we may say that the patient couldn't have survived two open heart surgeries, administration of a great amount of beta-blockers, and repeated cardiac arrest without neurological sequelae. 相似文献
54.
55.
O H Choi W L Padgett J W Daly 《The Journal of pharmacology and experimental therapeutics》1992,260(1):369-375
Two amphiphilic peptides from hymenopterid insects, melittin and mastoparan, stimulate secretion in a variety of cell types. In PC12 cells, both peptides stimulate calcium influx with melittin some 20-fold more potently than mastoparan. Melittin stimulates both breakdown of phosphoinositides (Pl) by phospholipase C to yield inositol phosphates and hydrolysis of phospholipids by phospholipase A2 to release arachidonic acid (AA). Mastoparan stimulates Pl breakdown, but has no effect on AA release. Maximal stimulation of Pl breakdown occurs at 1 to 2.5 micrograms/ml melittin and 30 micrograms/ml mastoparan, whereas maximal stimulation of AA release occurs at 2 to 5 micrograms/ml melittin. Organic calcium channel blockers (nifedipine, verapamil, diltiazem) have little or no effect on responses to the peptides. The influx of calcium elicited by melittin or mastoparan is completely or nearly completely blocked by inorganic calcium channel blockers (Co++, Mn++, Cd++). Mn++ and Cd++ inhibit melittin-induced Pl breakdown and AA release and mastoparan-induced Pl breakdown. Co++ has no effect on melittin-induced Pl breakdown and potentiates mastoparan-induced Pl breakdown. Pertussis toxin has no effect on the Pl breakdown induced by either peptide. The responses to melittin and mastoparan in PC12 cells are compared to those reported for maitotoxin. 相似文献
56.
A case of mycotic aneurysm of the intracavernous carotid artery is reported and the literature is reviewed on this uncommon entity. Nineteen cases have been reported, most often occurring in the clinical setting of meningitis. Management recommendations include angiographic confirmation of aneurysm and follow-up with magnetic resonance imaging during antibiotic therapy. Evidence of aneurysm enlargement is an indication for endovascular trapping of the aneurysm or carotid occlusion. 相似文献
57.
Tracy W. Harachi Yoonsun Choi Robert D. Abbott Richard F. Catalano Siri L. Bliesner 《Prevention science》2006,7(4):359-368
While there is growing awareness for the need to examine the etiology of problem behaviors across cultural, racial, socioeconomic, and gender groups, much research tends to assume that constructs are equivalent and that the measures developed within one group equally assess constructs across groups. The meaning of constructs, however, may differ across groups or, if similar in meaning, measures developed for a given construct in one particular group may not be assessing the same construct or may not be assessing the construct in the same manner in other groups. The aims of this paper were to demonstrate a process of testing several forms of equivalence including conceptual, functional, item, and scalar using different methods. Data were from the Cross-Cultural Families Project, a study examining factors that promote the healthy development and adjustment of children among immigrant Cambodian and Vietnamese families. The process described in this paper can be implemented in other prevention studies interested in diverse groups. Demonstrating equivalence of constructs and measures prior to group comparisons is necessary in order to lend support of our interpretation of issues such as ethnic group differences and similarities. 相似文献
58.
59.
Mi Sook Gwak Kwang-Woong Lee Shi Yeon Kim Jihyun Lee Jae Won Joh Sung Joo Kim Hwan Hyo Lee Jean Wan Park Gaab Soo Kim Suk-Koo Lee 《Liver transplantation》2005,11(3):331-335
During liver transplantation for hepatocellular carcinoma (HCC) patients, HCC could theoretically be introduced into the systemic circulation when salvaged blood is used with an autotransfusion device. Several reports have shown that some types of leukocyte depletion filters (LDFs) could completely reduce the risk for reintroducing some types of tumor cells. In this study, we tested the ability of the LDF (RCEZ1T, Pall Biomedical Co, NY, USA) to reduce the risk for reintroducing HCC cells in vitro by using a very sensitive detection method. We divided the test group into 6 groups: group I was 10 cells, group II was 20 cells, group III was 2 x 10(3) cells, group IV was 2 x 10(5) cells, group V was 2 x 10(6) cells, and group VI was 2 x 10(7) cells. The counted cells in 200 mL saline were passed through the RCEZ1T using the force of gravity. To identify the presence of cells, the pellet was resuspended, and polymerase chain reaction (PCR) was performed. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a housekeeping gene, was used as a primer. In groups I and II, the HCC cells were completely filtered in all experiments. However, in groups III, IV, and V, the HCC cells were not completely filtered in a few of the repeated experiments, with the unfiltered rate of tumor cells being between 8% and 20%. In group VI, the HCC cells were not completely filtered in all the repeated experiments. In conclusion, the RCEZ1T filter markedly reduced the risk for reintroduction of HCC cells. However, at high HCC cell load the filter cannot completely remove all the tumor cells. Further studies are required to assess the impact in clinical settings. 相似文献
60.
Effects of sodium salts of various monovalent inorganic anions on transdermal permeation of salicylic acid were investigated. In in-vitro experiment using a Franz-type diffusion cell and excised mouse skin, the permeation-enhancing activities of the sodium salts of inorganic anions were roughly proportional to lyotropic Hofmeister swelling abilities of the anions; F?<SO4 2?<Cl? <ClO4 ?<NO3 <SCN? <Br <I?, i.e. l, Br and SCN increased the flux of drugs through the mouse skin, while F?, SO4 2?, Cl?, ClO4 ? and NO3 ? decreased or did not affect the flux. In invivo experiment using the rabbit as the test animal, the plasma concentration of salicylic acid of the rabbit to which 10%-salicylic acid ointment containing 5%-Nal or NaBr was applied was significantly higher than that of the rabbit to which the ointment without the electrolytes was applied. The amounts of sterol leached out of stratum corneum sheet when the sheet was immersed in aqueous solutions of Nal, NaBr, or NaSCN were much more than that of stratum corneum immersed in aqueous solutions of the other inorganic anions. The FTIR/ATR spectroscopy showed that the peaks at 2853 cm?1 and 2924 cm?1 in the IR absorption spectrum of the stratum corneum sheet of the mouse were shifted to higher frequencies by the anions which enhanced the transdermal drug permeation, while not shifted by the anions which did not have any permeation-enhancing activities or have permeation-reducing activities. These results suggest that sodium salts of some anions such as iodide, bromide and thiocyanate enhance transdermal permeation of salicylic acid through swelling and perturbation of the skin structure by these anions. 相似文献