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The combined effects of alcohol and cigarette smoking on the cerebral circulation are unknown. The current study was designed (1) to compare the acute effects on cerebral vessels of cigarette smoking alone with those of alcohol plus cigarette smoking and (2) to clarify the mechanism or mechanisms underlying the cerebrovascular responses. In pentobarbital-anesthetized, mechanically ventilated Sprague–Dawley rats, we measured pial vessel diameters with the use of a cranial window preparation. Rats, pretreated with alcohol (n = 6; 1 g/kg/h, i.v.; 1-h infusion from t = −60 min to t = 0) or with saline (n = 6), were exposed to 60 puffs per minute of mainstream smoke from a 1 mg-nicotine cigarette. Inhalation of smoke caused pial arterioles to constrict at t = 30 s (8.4%) and, subsequently, to dilate (peak at t = 5–10 min; 18.7%). Pretreatment with alcohol caused pial vasodilation (14.0%), and, after inhalation of cigarette smoke, the pial vasodilation occurred earlier (peak at t = 1–5 min; 30.2%) and was larger, without an initial vasoconstriction. The plasma concentration of thromboxane (TX) B2 (a stable metabolite of TXA2) increased after this smoking, and alcohol pretreatment attenuated this increase (protocol as above). Cigarette smoking had a significant biphasic effect on cerebral arteriolar tone. However, alcohol suppressed the initial vasoconstriction, probably, at least in part, by attenuating the smoking-induced TXA2 production.  相似文献   
75.
We investigated expression of ameloblastin and sheathlin, recently cloned enamel matrix proteins from the rat and pig, in forming enamel immunocytochemically and immunochemically, using region-specific antibodies. The results obtained from the rat and pig were essentially the same. Antibodies which recognize the N-terminal region stained the secretory machinery of the secretory ameloblast and the entire thickness of the enamel matrix, especially the peripheral region of the enamel rod. Immunostained protein bands were observed near 65 or 70 kDa and below 20 kDa. C-terminal-specific antibodies stained the secretory machinery of the ameloblast and the immature enamel adjacent to the secretion sites. Immunostained protein bands were found ranging from 25 to 70 kDa. Antibodies which recognize a region in the protein just prior to the C-terminal region stained the cis-side of the Golgi apparatus but not the enamel matrix. Immunostained protein bands were observed of about 55 kDa. These results suggest that post-translational and post-secretory modifications of ameloblastin and sheathlin are similar to each other, and further showed that their cleaved N-terminal polypeptides concentrate in the prism sheath. We propose that sheathlin and ameloblastin share the same role in amelogenesis and should be classified as sheath proteins.  相似文献   
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A review of ten surgical cases of medullary carcinoma of the thyroid (MCT) demonstrates the usefulness of establishing a preoperative cytological diagnosis through the immunochemical staining of calcitonin (CT) and CEA in fine-needle aspiration (FNA) biopsy smears. If MCT is suspected after routinely performing May-Grünwald-Giemsa stained cytology of an FNA biopsy in the outpatient clinic, then CT and CEA staining is recommended for confirmation of MCT. The advantages of this immunochemical staining include that it can be carried out in the outpatient clinic within one day and also that it is much less costly than measuring serum CT and CEA.  相似文献   
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A patient evaluated for heart failure was found by routine radionuclide angiography to have a large internal iliac arteriovenous fistula of presumed postoperative origin. The value of radionuclide angiography is described with a review of the literature on such unusual cases.  相似文献   
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This study was performed to retrospectively compare changes in the levels of total cholesterol, non-HDL cholesterol, triglycerides, and immunosuppressive drugs, cyclosporine A and steroids in patients with living-relation renal transplants with those from non-heart-beating donors. We experienced 11 cases of kidney transplants from non-heart-beating donors during the period from April 1995 to May 2003. We evaluated 13 cases of kidney transplants from living-relation donors during the same period. The immunosuppressants used included mainly cyclosporine A as well as mycophenolate mofetil or azathioprine, steroid and ALG, or basiliximab. Over-night fasting lipids (total cholesterol, triglycerides and HDL cholesterol) were studied before renal transplantation and repeated after renal transplantation at 1, 3, 6 and 12 months. The levels of total cholesterol and triglycerides remained in the normal range before transplantation. However, the levels of total cholesterol increased siginificantly 1 and 3 months after transplantation from non-heart-beating donors and remained at higher levels up to 12 months after transplantation. A similar pattern in the levels of triglycerides was observed. The levels of HDL cholesterol remained unchanged and stayed in the normal range before and 1, 3, 6, and 12 months after transplantation from non-heart-beating donors. On the other hand, significant increases in non-HDL cholesterol were observed 3 and 6 months after transplantation from non-heart-beating donors. After transplantation from living-relation donors, levels of total cholesterol, triglycerides, and non-HDL cholesterol remained unchanged and remained in the normal range up to 12 months after transplantation. Although there were no significant differences in the total dosage of cyclosporine A between the patients with living-relation donors and those with non-heart-beating donors, a significant increase in the total dosage of methylprednisolone was observed in patients with non-heart-beating donors compared with those in the patients with living-relation donors. Renal function recovery in patients with living-relation donors was better than in those with non-heart-beating donors. These results may suggest that significant increases in total cholesterol, especially non-HDL cholesterol and triglycerides, were probably partly due to an increased use of immunosuppressants, steroids. It is necessary to aggressively control post-transplant hyperlipidemia and important to reduce or withdraw steroids in the selected, low-risk recipients as early as possible from the viewpoint of preventing post-transplant hyperlipidemia.  相似文献   
80.
It was confirmed that esterolytic activity was significantly elevated in plasma of patients with acute pancreatitis, which correlated better with the stage of the disease than serum amylase level. Using the several column chromatography procedures, pancreatic kallikrein, trypsin and pancreatic elastase were separated and purified from alpha 2-macroglobulin (alpha 2-M) fractions of patients plasma with acute pancreatitis. From this this result, it was confirmed that kallikrein was liberated into the blood stream from the pancreas during attacks of acute pancreatitis and the liberated kallikrein combined with alpha 2-M. Furthermore, the coexistence of trypsin is required for the complex formation of alpha 2-M and pancreatic kallikrein. It was speculated that alpha 2-M might be decomposed by the excessive amount of elastase, and consequently, might release all of its combining enzymes into the blood stream. In the present study, the activation mechanism of fibrinolytic enzyme system in plasma by human pancreatic elastase was investigated. Elastase not only converted the co-existing plasminogen to low molecular weight plasminogen which could be easily activated by the activators, but also inhibited alpha 2-M and alpha 2-plasmin inhibitor, and consequently, induced the activation of the fibrinolytic enzyme system in plasma. Furthermore, it was also confirmed that elastase could activate plasma kallikreinogen to kallikrein.  相似文献   
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