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991.
We have previously shown that the acute phase reaction of the pancreas is a powerful emergency mechanism which protects the organism against further pancreatic aggression. In an attempt to understand the mechanisms involved in this protective effect we tried to characterize at the molecular level the phenotypic changes of the pancreatic cell during acute stress. Using a systematic approach, we identified the PC3/TIS21/BTG2 mRNA as strongly overexpressed in pancreas during the acute phase of pancreatitis. PC3/TIS21/BTG2 mRNA is also overexpressed in liver and kidney during acute pancreatitis but not in the other tissues analyzed. In addition, PC3/TIS21/BTG2 mRNA is overexpressed in kidney after a 30-min ischemia. Since acute pancreatitis and kidney ischemia-reperfusion-induced injury were associated with apoptosis, and PC3/TIS21/BTG2 has an antiapoptotic activity, we speculate that this protein may play a role in the control of apoptosis progression in these tissues.  相似文献   
992.
N-1 and N-2 substituted pyrazolo[4,5-g]pyrido[1,2-a]benzimidazoles were prepared regioselectively, and cytotoxicities evaluated in vitro against K562 and HL60 cells. All compounds displayed weaker activity than doxorubicin against sensitive lines, but showed the same activity against resistant cell lines (multidrug resistance+, (MDR+); K562R and HL60R) indicating no resistance phenomena.  相似文献   
993.
Case management traditionally has been performed by occupational health nurses and rehabilitation professionals. The rapid growth of managed care was the impetus for defined standards and formal credentialing.  相似文献   
994.
995.
The clinicopathological characteristics of 343 naevi of the conjunctiva were studied. A significant increase in the number of naevi excised per year was observed. This may have been caused by an increased exposure to actinic rays. An approximately even distribution was found between the three main locations: caruncle, limbal area and eye ball. Intrastromal naevi were excised at a higher median age than compound naevi, and the lowest median age at excision was for junction naevi, which is in accordance with the known histopathological nature of naevi. Recurrence occurred in nine patients (2.7%), and one had transformed into a malignant melanoma. Eight of the recurring naevi were located in the limbal area. Eight of the nine patients were women, suggesting hormonal factors as a possible cause. Recommendations for the handling of conjunctival naevi are given, based on the present findings and on previous reports.  相似文献   
996.
Few well-documented cases of central nervous system involvement in patients with hepatitis C virus infection have been reported. We describe three patients (two men and one woman) with cerebral involvement (ischemia and/or hemorrhage). Hepatitis C virus infection was confirmed in all patients by polymerase chain reaction detection of hepatitis C virus RNA. These three cases document the occurrence of central nervous system involvement in patients with hepatitis C virus infection and mixed cryoglobulinemia. Cerebral involvement may be the initial manifestation of hepatitis C virus infection.  相似文献   
997.
OBJECTIVE: To assess the safety and efficacy of a fixed dose of recombinant activated factor VII (rFVIIa; NovoSeven) in the home setting for mild to moderately severe joint, muscle; and mucocutaneous bleeding episodes in patients with haemophilia A or B with inhibitors. DESIGN: Multicentre, open-label, single arm, phase III study of one year duration. METHODS; Patients or their caregivers administered up to three doses of rFVIIa (90 microg/kg i.v.) at 3 h intervals within 8 h of the onset of a mild to moderate bleeding episode. Once the subject considered that rFVIIa had been "effective" with regard to haemostasis (after 1-3 injections), one further (maintenance) dose of rFVIIa was administered. RESULTS: Of 60 patients enrolled, 56 experienced at least one bleed, and 46 completed the one year study. 614 of 877 bleeds (70%) were evaluable according to protocol definitions. Haemostasis was rated as "effective" in 92% (566/614) of evaluable bleeds after a mean of 2.2 injections. For successfully treated episodes, the time from onset of bleeding until administration of the first injection was 1.1+/-2.0 h (mean+/-SD). Twenty-four hours after initial successful response, haemostasis was reported as having been maintained in 95% of cases. Efficacy was comparable for muscle, joint and target joint, and mucocutaneous bleeding episodes. In an intent-to-treat analysis of all 877 bleeding events, efficacy outcomes were equivalent to the evaluable bleeds, with an effective response in 88% of treated episodes. Treatment-related adverse events occurred in 32 (3% of all) bleeding episodes and consisted of re-bleeds/new bleeds in more than 50% (18/32) of these events. A single episode of superficial thrombophlebitis was the only thrombotic complication encountered, and there were no patient withdrawals due to adverse events. Development of FVII(a) antibodies could not be detected, and hypersensitivity reactions to rFVIIa were not reported. CONCLUSION: rFVIIa is effective and well tolerated when used in the home setting to treat mild to moderate bleeding episodes in patients with haemophilia A or B with inhibitors.  相似文献   
998.
999.
Gcn5p is the catalytic subunit of several type A histone acetyltransferases (HATs). Previous studies performed under a limited range of solution conditions have found that nucleosome core particles and nucleosomal arrays can be acetylated by Gcn5p only when it is complexed with other proteins, e.g. Gcn5-Ada, HAT-A2, and SAGA. Here we demonstrate that when assayed in buffer containing optimum concentrations of either NaCl or MgCl2, purified yeast recombinant Gcn5p (rGcn5p) efficiently acetylates both nucleosome core particles and nucleosomal arrays. Furthermore, under conditions where nucleosomal arrays are extensively folded, rGcn5p acetylates folded arrays approximately 40% faster than nucleosome core particles. Finally, rGcn5p polyacetylates the N termini of free histone H3 but only monoacetylates H3 in nucleosomes and nucleosomal arrays. These results demonstrate both that rGcn5p in and of itself is catalytically active when assayed under optimal solution conditions and that this enzyme prefers folded nucleosomal arrays as a substrate. They further suggest that the structure of the histone H3 N terminus, and concomitantly the accessibility of the H3 acetylation sites, changes upon assembly into nucleosomes and nucleosomal arrays.  相似文献   
1000.
Traditional T2-based imaging techniques are geared toward imaging long-T2 species. Traditional techniques are, therefore, not optimal in clinical situations where the information of interest lies in the short-T2 species. T2-selective RF excitation (TELEX) is a technique for obtaining a T2-based contrast that highlights short-T2 values while suppressing long-T2 values-opposite to traditional T2 contrast. Previously, TELEX has been demonstrated qualitatively to highlight only very short-T2 values (T2 approximately 0.001 s). When applied to longer T2 values (T2 > or = 0.01 s), TELEX becomes sensitive to deltaB0 non-uniformities. This restricts its application to problems in which the T2 of interest is very short. In this study, TELEX is characterized quantitatively. Furthermore, a bandwidth broadening scheme is developed that reduces the deltaB0 sensitivity of TELEX. This permits the technique to be applied to longer T2 values. The capabilities and limitations of a practical implementation of TELEX are discussed.  相似文献   
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