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991.
Clemens Walter Dogan Kaner Dorothea C. Berndt Roland Weiger Nicola U. Zitzmann 《Journal of clinical periodontology》2009,36(3):250-257
Aim: To investigate the use of cone beam computed tomography (CBCT) in assessing furcation involvement (FI) and concomitant treatment decisions in maxillary molars. Material and Methods: Twelve patients with generalized chronic periodontitis were consecutively recruited and CBCT was performed in maxillary molars (n=22) with clinical FI and increased probing pocket depths. CBCT images were analysed and FI, root length supported by bone and anatomical features were evaluated. FI and treatment recommendations based on clinical examinations and periapical radiographs were compared with data derived from CBCT images. Results: The estimated degree of FI based on clinical findings was confirmed in 27% of the sites, while 29% were overestimated and 44% revealed an underestimation according to CBCT analyses. Among degree I FI, 25% were underestimated, among degree II and II–III, the underestimation was as high as 75%, while all sites with degree III FI were confirmed in the CBCT. Discrepancies between clinically and CBCT‐based therapeutic treatment approaches were found in 59–82% of the teeth, depending on whether the less invasive or the most invasive treatment recommendation was selected for comparison. Conclusions: CBCT images of maxillary molars may provide detailed information of FI and a reliable basis for treatment decision. 相似文献
992.
993.
Roland R. Griffiths R. J. Lamb Christine A. Sannerud Nancy A. Ator Joseph V. Brady 《Psychopharmacology》1991,103(2):154-161
Self-injection of 12 sedative-anxiolytics was examined in baboons. Intravenous injections and initiation of a 3-h time-out were dependent upon completion of a fixed-ratio schedule requirement, permitting eight injections per day. Before testing each dose of drug, self-injection performance was established with cocaine. Subsequently, a test dose was substituted for cocaine. At some doses, all five of the benzodiazepines examined (alprazolam, bromazepam, chlordiazepoxide, lorazepam, triazolam) maintained rates (number of injections per day) of drug self-injection above vehicle control in each of the baboons tested. Maximum rates of benzodiazepine self-injection were generally submaximal. Of the benzodiazepines examined, triazolam maintained the highest rates of self-injection. Among the three barbiturates tested, methohexital generally maintained high rates of self-injection in contrast to hexobarbital and phenobarbital, which only maintained low rates. Of the four non-benzodiazepine non-barbiturate sedatives examined, both chloral hydrate and methyprylon occasionally maintained high rates of self-injection. Although there were differences within and across animals, baclofen maintained intermediate rates of self-injection. The novel anxiolytic buspirone maintained only low rates of self-injection that were not different from vehicle. This study further validates the self-injection methodology for assessing sedative-anxiolytic abuse liability and provides new information about drug elimination rate as a determinant of drug self-administration. 相似文献
994.
995.
996.
Nicola E. Hiemann Rudolf Meyer Ernst Wellnhofer Manfred Hummel Roland Hetzer 《The International journal of angiology》2002,11(4):225-229
This study tests the correlation of coronary angiographic findings with the extent of microvascular reaction in right ventricular endomyocardial biopsies (EMBs) in transplanted hearts. In EMBs (n = 209) of 30 heart transplant patients (8 female, 22 male, mean age 48 years) microvascular reaction, i.e. endothelial cell swelling and vascular wall thickening (both grade 0-2), was graded by light microscopy at ×200. Patients' first and last coronary angiography (CA) (mean time after heart transplantation [HTx] 8 and 44 months) were graded according to the Stanford Classification and the presence of diameter irregularities was evaluated semi-quantitatively. We found a correlation of angiographic type B lesions with endothelial cell swelling during the first 5 months and vascular wall thickening during the fifth to fourteenth month after HTx (p<0.05). In patients with diameter irregularities and type B1 lesions in their first CA and type C lesions in their last CA, there was pronounced endothelial cell swelling in the early postoperative period (p<0.05). There was a tendency towards an increased vascular wall thickening in these patients during the later postoperative period. Graft vessel disease affects large and small coronary arteries and capillaries. Small vessel disease is characterized by architectural changes in blood vessel walls. Serial investigations of EMBs for diagnosis of small vessel disease complement the present diagnostic tools. 相似文献
997.
János Mester Rolf Weller Malte Clausen Franz Bitter Eberhard Henze Roland Lietzenmayer Willi-Ernst Adam 《European journal of nuclear medicine and molecular imaging》1991,18(3):184-190
The upward creep of the heart during myocardial single photon emission tomography (SPET) acquisition has been reported as a frequent source of false-positive results. The aim of this study was to simplify the detection and correction of this upward creep and to estimate its clinical relevance during routine patient care. To recognize the upward heart motion a straight line was fitted to the upper and lower border of consecutively displayed tomographic projection images. In this way, vertical translation of at least 1 pixel in size could be detected easily. On the assumption of a slow but continuous upward motion a fast interpolation correction method was developed. From 100 consecutive, supine, ergometric exercise studies, 1, 2 or 3 pixels of upward creep were found in 16, 4 or 3 patients, respectively. It was found that an upward creep of at least 2 pixels (7/100 cases) led to evident, mostly antero-septal defects on quantitative bull's-eyes, whereas only upward creeps of 3 pixels or more (3/100 cases) produced false-positive diagnostic results. The simple correction method offered a sufficient compensation of image and/or bull's-eye artefacts. These clinical findings could be reproduced in a computer model. Thus, it can be stated that clinically significant upward creep of the heart during stress SPET acquisition is relatively rare; it may have been overestimated in the past, and its artificial effects can be corrected by a quick and simple algorithm.Research fellow of the Alexander von Humboldt Foundation working at Department of Nuclear Medicine, University Medical School Szeged, Hungary 相似文献
998.
Jürgen Schrader Stephan Lüders Hans-Christoph Diener Hermann Haller Roland E Schmieder Klaus Wahle Wenefrieda Smolka Claudia Jung Kurt Bestehorn 《Medizinische Klinik》2008,103(7):491-499
BACKGROUND AND PURPOSE: As arterial hypertension is the most important risk factor for ischemic stroke, the relevant guidelines recommend rigorous treatment to normalize blood pressure. Hypertension can also be associated with cognitive decline and dementia. Therefore, the effect of a long-term therapy with the AT(1) antagonist losartan (+/- hydro chloro thiazide [HCTZ]) on cognitive function in patients with essential hypertension and additional cerebrovascular risk factors was investigated. PATIENTS AND METHODS: Prospective, open observational study in 6,206 adult patients with known essential hypertension and cerebrovascular risk factors (most with a 10-year stroke risk of >/= 20% based on the Framingham Score). Demographic data, blood pressure, selected laboratory parameters, and cognitive function (c.I. test) were determined at baseline and after 3, 6, and 12 months. RESULTS: The patients' mean age was 65.8 +/- 10.7 years and 46.1% of the patients were male. In addition to treatment with losartan +/- HCTZ, 54.1% of the patients received one or more additional antihypertensive agents. After 1 year of treatment, systolic/diastolic blood pressure fell from its baseline level of 158.1/90.3 mmHg to 137.3/80.6 mmHg (-20.8/-9.7 mmHg). The proportion of patients with no/mild/severe cognitive impairment was 30.0%/30.3%/39.7% at baseline and 34.8%/28.1%/37.1% at the end of the study. In patients with cognitive impairment, fibrinogen and hsCRP (high-sensitive C-reactive protein) levels were significantly elevated. Adverse events (AEs) were reported in 231 patients (3.7%), while serious/nonserious AEs possibly related to the study medication were reported in only six (0.1%) and 38 patients (0.6%), respectively. CONCLUSION: A high proportion of patients with hypertension shows cognitive impair ment; therefore, use of appropriate tests to detect this should be considered. The losartan-based antihypertensive treatment increased the proportion of patients with normal cognitive function, reduced blood pressure, and was well tolerated in the primary-care setting. 相似文献
999.
1000.