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21.
Photoreactive (meth)acrylate monomers having mesogenic groups based on 4-hexyloxy-4′-(3-methyl-2-butenyloxy)biphenyl and 4-hexyloxy-4′-(2-butenyloxy)biphenyl were synthesized. Methacrylate monomers ( 3c, d ) and acrylate monomer having 3-methyl-2-butenyloxy group ( 3b ) were polymerized by free radical mechanism; the acrylate monomer having 2-butenyloxy group ( 3a ) caused gelation during the polymerization. To obtain photoreactivity, 4-benzoylphenyl (meth)acrylates were radically copolymerized with monomers 3b and 3d . Thermal behavior of (co)polymers was determined by differential scanning calorimetry, polarized optical microscopy and temperature-controlled X-ray analysis. (Co)polymers showed liquid-crystalline behaviour with nematic and smectic phases. UV-irradiation was used to photochemically crosslink copolymer films, and the resultant films were insoluble in organic solvents. The uniaxially oriented copolymer thin film was photo-crosslinked and showed thermally stable orientation.  相似文献   
22.
We have shown earlier that nicotinic agonists induce the release of noradrenaline from chick sympathetic neurons in culture in two ways: (a) by activating the postsynaptic nicotinic receptors on nerve cell bodies, giving rise to spreading electrical activity and opening of voltage operated calcium channels in neuronal processes; (b) by activating the presynaptic nicotinic receptors on neuronal processes. In the present work, we investigated the contribution of various pathways to the observed Ca2+ influx and subsequent noradrenaline release. Sympathetic neurons in culture were stimulated either by the nicotinic agonist dimethylphenylpiperazinium or electrically, in the presence or absence of tetrodotoxin and of specific blockers of calcium or nicotinic channels, and the effects on [Ca2+]i in the area of neuronal processes and on noradrenaline release were measured. Under control conditions, the N-type channel blocker ω-conotoxin (0.1 μmol/1) diminished the release of noradrenaline and the increase of intraterminal Ca2+ by 48% and 55%, respectively, whereas the L-type channel blocker (+)Bay k 8644 (1 μmol/1) diminished the release of noradrenaline by 25% and the increase of [Ca2+]i by 39%. The P-type channel blocker ω-agatoxin (0.3 μmol/1) had no effect. The effects of the L-type channel ligands were complex and could only be explained on the assumption that, at high concentrations, these drugs also act as nicotinic antagonists. Tetrodotoxin blocked the Ca2+ response evoked by electrical stimulation whereas DMPP applied in the presence of tetrodotoxin still evoked an increase of [Ca2+]i and the release of noradrenaline (27% and 30% of control without tetrodotoxin, respectively). These residual responses were not blocked by any of the calcium channel blockers used or by their combination. Apparently, a substantial part of the influx of Ca2+ induced by the activation of presynaptic nicotinic receptors is not carried by the N-, L- or P-type channels and probably occurs directly via the open channels of nicotinic receptors.  相似文献   
23.
Abstract: Despite the widespread belief that medical authority is under increasing challenge, no adequate research instrument has been available to measure relevant community attitudes. This paper reports the development of the Attitude Toward Medical Practitioners Scale (the AMPS). Samples of Australians (in total N > 1000) completed the AMPS, using three different procedures. The reliability of the scale, assessed by coefficient alpha, ranged from 0.80 to 0.86. A principal component analysis of the AMPS yielded loadings on each item exceeding 0.3 on the first unrotated factor; subsequent varimax rotation revealed dimensions associated with critical attitudes to doctors and evaluations of doctors' interpersonal competence and technical expertise. Positive and significant correlations between the AMPS and one measure of the General Attitude toward Institutional Authority (GAIAS) strongly suggested that the scale is consistent with generalised evaluations of community authorities. The specific validity of the AMPS was supported for each of three samples, using as validating criteria respondent ratings of the last doctor visited, satisfaction with the consultation and reported compliance with the doctor's advice. Significant improvements were found in the prediction of each of these criteria by the addition of the AMPS to contributions made by the GAIAS and the demographic variables, age and sex. The AMPS is an appropriate measure for assessing community attitudes towards medical practitioners conceived as institutional authorities, at least in the Australian context.  相似文献   
24.
A 72-year-old fisherman who was positive for the HCV antibody developed an annular, erythematous, infiltrated lesions on sun-exposed areas. The lesions were diagnosed as annular elastolytic giant cell granuloma both clinically and histologically. Topical corticosteroid and cryotherapy with liquid nitrogen for several months failed to improve the lesions. We then started dapsone, a known anti-oxidant, at 50 mg/day. A month later, the margins of the erythematous lesions faded, and the infiltration gradually decreased. No recurrence has been observed for one year after the start of the therapy. Anti-oxidative therapy appears to be effective for annular elastolytic giant cell granuloma and could be an alternate therapy for refractory granulomatous disease.  相似文献   
25.
26.
THIS IS THE FIRST OF 2 ARTICLES EVALUATING cardiac events in patients undergoing noncardiac surgery. In this article, we review the magnitude of the problem, the pathophysiology of these events, approaches to risk assessment and communication of risk. The number of patients undergoing noncardiac surgery worldwide is growing, and annually 500 000 to 900 000 of these patients experience perioperative cardiac death, nonfatal myocardial infarction (MI) or nonfatal cardiac arrest. Although the evidence is limited, a substantial proportion of fatal perioperative MIs may not share the same pathophysiology as nonoperative MIs. A clearer understanding of the pathophysiology is needed to direct future research evaluating prophylactic, acute and long-term interventions. Researchers have developed tools to facilitate the estimation of perioperative cardiac risk. Studies suggest that the Lee index is the most accurate generic perioperative cardiac risk index. The limitations of the studies evaluating the ability of noninvasive cardiac tests to predict perioperative cardiac risk reveals considerable uncertainty as to the role of these popular tests. Similarly, there is uncertainty as to the predictive accuracy of the American College of Cardiology / American Heart Association algorithm for cardiac risk assessment. Patients are likely to benefit from improved estimation and communication of cardiac risk because the majority of noncardiac surgeries are elective and accurate risk estimation is important to allow informed patient and physician decision-making.  相似文献   
27.
A 52‐year‐old Japanese woman who presented with gastrointestinal (GI) bleeding underwent a proximal gastrectomy for a gastrointestinal stromal tumor (GIST) with a foveolar hyperplasia at the apex of the tumor, 4.5 cm in size, located in the upper body of the stomach. Although GIST are often asymptomatic and are found only incidentally, clinical symptoms such as bleeding, abdominal pain, or obstruction, occasionally lead to a premorbid diagnosis. When submucosal tumors present GI bleeding, the source of the bleeding usually is an ulceration of the mucosa over the tumor. However, in the present study, it was thought that the bleeding originated from the region of foveolar hyperplasia.  相似文献   
28.
Objective Postoperative pericardial effusion commonly occurs after open heart surgery. However, after general thoracotomy such as pulmonary resection, there have been few reports of pericardial effusion. The purpose of this study is to investigate patients with pericardial effusion following pulmonary resection.Methods: Among 2,385 patients with pulmonary resection for lung neoplasm in our institute, eight patients, whose pericardium had never been opened during the operation, developed pericardial effusion. The clinical characteristics of the eight patients were analyzed.Results: Pericardial effusion after pulmonary resection was divided into two subtypes: pericardial effusion in three patients with left thoracotomy occurring within 30 days postoperatively, and pericardial effusion in the remaining five patients with right thoracotomy occurring more than 30 days postoperatively. Pericardiotomy or pericardiocentesis was performed in three symptomatic patients, and the remaining five asymptomatic patients were treated with diuretics. Pericardial effusion disappeared in three of the five patients about 1–3 months after the conservative treatment, while, in the remaining patients, because pericardial effusion had increased gradually, pericardiocentesis was performed.Conclusion: From our experience, the treatment strategy of drainage for early pericardial effusion and diuretics for late pericardial effusion seems to be appropriate. (Jpn J Thorac Cardiovasc Surg 2006; 54:193-198)  相似文献   
29.
BACKGROUND: The development of atherosclerotic cardiovascular complications caused by hyperlipidemia is a common and serious problem for long-term survivors of organ transplantation. However, adhesion molecules such as intercellular adhesion molecule (ICAM)-1 and lymphocyte function-associated antigen (LFA)-1 are involved in allograft rejection, possibly by providing costimulatory signals. 3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor cerivastatin has been shown to suppress ICAM-1 expression in acute inflammatory responses. METHODS: In this study, we evaluated the immunosuppressive effects of cerivastatin in rat cardiac allografts. The hearts of Fischer rats were transplanted heterotopically into Lewis rats. Cerivastatin (2 mg/kg) was administrated intraperitoneally to recipients for 7 consecutive days from the day before transplantation. RESULTS: Graft survival in the cerivastatin-treated group (n = 8) was significantly longer than in controls (n = 10) (24.6 +/- 2.2 days vs 10.2 +/- 1.3 days, p < 0.05). Mixed lymphocyte reaction (MLR) showed that on Day 8 after grafting, the proliferative response of alloreactive T cells against F344 alloantigen in cerivastatin-treated rats was significantly more suppressed than in Lewis rats. The Interleukin-2 concentration of supernatant in MLR cultures in the cerivastatin-treated group was lower than in the control group. Immunohistochemical analysis showed that the percentage of CD4-positive cells to infiltrating mononuclear cells was less prominent in the cerivastatin-treated group (9.8% +/- 2.2%) than in the control group (20.9% +/- 3.2%). CONCLUSIONS: The HMG-CoA reductase inhibitor cerivastatin effectively suppressed acute graft rejection, possibly by blocking intercellular signals via ICAM/LFA-1, and cerivastatin may be a candidate for treating patients with hyperlipidemia who undergo organ transplantation.  相似文献   
30.
Collagenous colitis is an inflammatory mucosal disorder of the colon with distinctive histopathological features, including a thickened subepithelial collagen layer. The clinical course is usually benign, but serious complications, including death, may occur. In the present report, a 69-year-old woman with watery diarrhea and collagenous colitis developed bloody diarrhea that was refractory to treatment medications, including corticosteroids and azathioprine. Endoscopic and histopathological studies showed a focal neutrophilic inflammatory process that progressed to a diffuse and extensive form of colitis, eventually requiring total proctocolectomy. Careful histological review of the resected colon showed no evidence of persistent collagenous colitis. These findings suggest an important need for continued long-term follow-up of patients with collagenous colitis because superimposed and serious colonic complications may occur, including a severe and extensive pancolitis refractory to medications and necessitating total proctocolectomy.  相似文献   
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