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101.
102.
Carcinoma of the fourth part of the duodenum: Report of a case   总被引:1,自引:0,他引:1  
Primary carcinoma of the duodenum is rare, accounting for only 0.35% of all gastrointestinal carcinomas, and carcinoma of the fourth part of the duodenum constitutes approximately 10% of duodenal carcinomas. Since the predominant symptoms of tumors in this part of duodenum are related to upper intestinal obstruction, the diagnosis is usually made late. We report the case of a 66-year-old man who presented with anemia, weight loss, and upper intestinal obstruction, and was found to have advanced primary carcinoma of the fourth part of the duodenum by upper gastrointestinal series and computed tomography (CT). A review of the literature indicates that survival, which is related to nodal status, the grade of the tumor, and surgical results, seems to be longer in patients with carcinoma in this part of the duodenum compared to those with carcinomas in other parts of the duodenum. Moreover, segmentary resection has been reported to achieve a favorable outcome.  相似文献   
103.
1,25-Dihydroxyvitamin D(3) (calcitriol) therapy has been extensively used for posttransplant osteoporosis. Beside its effect on bone metabolism, calcitriol has an important immunomodulatory effect. We evaluated the effects of oral calcitriol therapy on allograft function and parathyroid hormone levels after renal transplantation. The patients were retrospectively selected from a renal transplant patient population who received calcitriol (group 1, n = 59, 36 male/23 female, follow-up: 52.8 +/- 12.2 months) compared with group (group 2, n = 52, 42 male/9 female, follow-up: 62.0 +/- 24.4 months) without calcitriol therapy after renal transplantation. Calcitriol therapy was started 24.0 +/- 19.1 months posttransplantation. All patients were under three-drug immunosuppression. The pretransplant and posttransplant data were studied retrospectively. Additionally, creatinine levels before and after the initiation of calcitriol therapy were recorded at 6 months intervals for 3 successive years. Our results were analyzed according to the first and third year on therapy data. According to the first year data, there were no differences in patient groups in terms of creatinine and iPTH levels. In the third year, the patients in group 1 showed significantly lower creatinine (P = .01) and iPTH (P < .04) levels and needed lower pulse steroid doses (P < .04). According to a Friedman repeated measures variance test, the creatinine level was significantly lower among group I (P < .04) at 3-year follow-up. In conclusion, even a delayed start of calcitriol therapy after renal transplantation exerts a protective effect on renal allograft function and prevents the development of hyperparathyroidism.  相似文献   
104.
OBJECTIVE: Long-term inhalation of thinners may cause damage, both to the lungs and to other organ systems. It causes cellular damage via formation of reactive oxygen species. The lung is protected from oxidative stress by the glutathione (GSH) antioxidant system which can be augmented by the thiol drug, N-acetylcysteine (NAC). This study investigated the protective effect of NAC on peroxidative changes in rat lungs exposed to inhalation of thinners for 8 weeks. METHODOLOGY: Seventy-two male Wistar albino rats were used and divided into two groups: one group inhaled only thinners (TI), while the other inhaled TI plus NAC. Rats in the TI and TI + NAC groups were divided into four subgroups (each consisting of eight rats) according to the duration of exposure to TI: 2, 4, 6 and 8 weeks. A control group (n = 7) of rats inhaled neither TI nor NAC. Malondialdehyde (MDA) and GSH levels, and superoxide dismutase (SOD) activities were determined in the lung tissues. Histopathological findings were evaluated as acute and chronic changes in the alveoli and interstitium in the TI and TI + NAC groups and compared with those in the control group. RESULTS: While tissue MDA levels in the groups inhaling TI for 4, 6 and 8 weeks were significantly higher than those in the control groups (P < 0.01, P < 0.01, P < 0.0001, respectively), GSH levels were significantly lower (P < 0.05, P < 0.01, P < 0.01, respectively). Tissue SOD activities in the groups inhaling TI for 6 and 8 weeks were significantly lower than those in the control group (P < 0.05, P < 0.01, respectively). In the TI group, MDA levels were significantly increased (P < 0.01) with increasing duration of inhalation (from the second week through to the eighth week), while GSH levels and SOD activities were significantly decreased (P < 0.01, P < 0.01). Tissue MDA levels were significantly lower in the TI + NAC groups across all inhalation periods, when compared with the TI groups (P < 0.01, P < 0.0001, P < 0.0001, P < 0.0001, respectively). Tissue GSH levels in the TI + NAC groups were significantly higher than those of the TI groups (respective values: P < 0.05, P < 0.01, P < 0.01, P < 0.0001). Tissue SOD activities in the TI + NAC groups were significantly higher than those of the TI groups (respective values: P < 0.05, P < 0.0001, P < 0.05, P < 0.0001). Pathological examinations with light microscopy did not show any beneficial effect of NAC application in terms of deferring or alleviating the negative effects of TI. CONCLUSIONS: Thinners are agents that cause imbalance between oxidants and antioxidants produced by aerobic cellular systems. This imbalance between oxidant and antioxidant systems is decreased by the effect of NAC. However, ultrastructural studies may be needed to substantiate this evidence morphologically, as light microscopy was inconclusive.  相似文献   
105.
Ozdemir K  Altunkeser BB  Içli A  Ozdil H  Gök H 《Chest》2003,124(1):219-226
OBJECTIVE: The diagnosis of right ventricular myocardial infarction (RVMI) accompanied by acute inferior myocardial infarction (MI) is still a problem that we encounter. This study was designed to find out the usefulness both of peak myocardial systolic velocity (Sm) and of the myocardial performance index (MPI) of the right ventricle measured by pulsed-wave tissue Doppler imaging (TDI) in assessing right ventricular function. METHODS: Sixty patients who experienced a first acute inferior MI (mean [+/- SD] age, 57 +/- 9 years) were prospectively assessed. An ST-segment elevation of >or= 0.1 mV in V(4)-V(6)R lead derivations was defined as an RVMI. From the echocardiographic apical four-chamber view, the Sm, the peak early diastolic velocity, peak late diastolic velocity, the ejection time, the isovolumetric relaxation time, and the contraction time of the right ventricle were recorded at the level of the tricuspid annulus by using TDI. Then, the MPI was calculated. The patients were classified into the following three groups, according to the localization of the infarct-related artery (IRA) detected using coronary angiography: group I, proximal right coronary artery; group II, distal right coronary artery; and group III, circumflex coronary artery. RESULTS: RVMIs were detected in sixteen patients, and the IRA in 27 patients was the proximal right coronary artery. The right ventricular Sm was observed to be significantly low in patients with RVMIs and those in group I compared to those without RVMIs and those in groups II and III (10.9 +/- 1.3 vs 14.3 +/- 3.2 cm/s, respectively [p < 0.001]; 11.5 +/- 2.5 vs 15.1 +/- 3 cm/s, respectively; and 14.9 +/- 2.6 cm/s, respectively [p < 0.001]). In the diagnosis of RVMI, the values for sensitivity, specificity, negative predictive value, and positive predictive value of Sm < 12 cm/s were 81%, 82%, 92%, and 62% respectively, and in the diagnosis of the proximal right coronary artery as the IRA, those values were 63%, 88%, 74%, and 81%, respectively. The MPI was high in the same patient groups (0.83 +/- 0.12 vs 0.57 +/- 0.11 in those patients without RVMI, respectively, [p < 0.001]; 0.74 +/- 0.13 vs 0.56 +/- 0.15 in group II and 0.54 +/- 0.07 in group III, respectively [p < 0.001]). The sensitivity, specificity, negative predictive value, and positive predictive value of an MPI of > 0.70 in the diagnosis of RVMI were calculated as 94%, 80%, 97%, and 63%, respectively, and in the diagnosis of the proximal right coronary artery as the IRA, those values were 78%, 91%, 83%, and 88% respectively. CONCLUSIONS: An Sm <12 cm/s and an MPI > 0.70 obtained by TDI may define RVMI concomitant with acute inferior MI, and the IRA.  相似文献   
106.
The simultaneous spectrophotometric determination of ascorbic acid (AA) and acetylsalicylic acid (ASA) in effervescent tablets in the presence of the overlapping spectra was accomplished by the continuous wavelet transform (CWT), derivative spectrophotometry (DS) and partial least squares (PLS) approaches without using any chemical pre-treatment. CWT and DS calibration equations for AA and ASA were obtained by measuring the CWT and DS amplitudes corresponding to zero-crossing points of spectra obtained by plotting continuous wavelet coefficients and first-derivative absorbance values versus the wavelengths, respectively. The PLS calibration was constructed by using the concentration set and its full absorbance data consisting of 850 points from 220 to 305 nm in the range of 210-310 nm. These three methods were tested by analyzing the synthetic mixtures of the above drugs and they were applied to the real samples containing two commercial pharmaceutical preparations of subjected drugs. A comparative study was carried out by using the experimental results obtained from three analytical methodologies and precise and accurate results were obtained.  相似文献   
107.
The vascular effect of salvigenin (6-hydroxyapigenin 6,7,4' -trimethyl ether), a natural flavone, was investigated in comparison with another flavone, 6-hydroxyluteolin 6,7,3',4' -tetramethyl ether in rat aortic rings. Cumulative addition of their increasing concentrations (10(-9)-10(-4)M) produced graded relaxations on rings precontracted with noradrenaline (10(-6) M) and KCl (40 mM). The maximal relaxations induced by flavones were similar, however, based on their pEC50 values salvigenin displayed a higher potency than 6-hydroxyluteolin 6,7,3',4'-tetramethyl ether. Endothelium removal markedly reduced the relaxations to salvigenin while the responses to 6-hydroxyluteolin 6,7,3',4'-tetramethyl ether were partially affected. In addition, a significant decrease was observed in maximal responsiveness and sensitivity to flavones in the presence of L-NOARG, a NO synthase inhibitor. The cyclooxygenase inhibitor indomethacin significantly inhibited the relaxations to salvigenin, but not altered the responses to 6-hydroxyluteolin 6,7,3',4'-tetramethyl ether. Our results provide evidence that salvigenin is an effective flavone in causing vasorelaxation which appears to be mediated by endothelium derived NO and prostacyclin. Whereas, the other flavone, 6-hydroxyluteolin 6,7,3',4'-tetramethyl ether induced relaxant responses are partially endothelium, presumably NO mediated.  相似文献   
108.
109.
We presented a 77‐year‐old man with hypertrophic obstructive cardiomyopathy applied with flail tricuspid leaflet and severe tricuspid regurgitation leading to right heart failure 2 months after the failed septal ablation. The ruptured anterior tricuspid papillary muscle resulted from infarction of the base of anterior papillary muscle of the right ventricle (RV) confirmed by magnetic resonance imaging. As the septomarginal band is frequently lit up by intracoronary contrast that particular attention should be paid to the RV papillary muscles. And, if the papillary muscles or the RV free wall is brightened, then the use of that septal artery should be avoided.  相似文献   
110.
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