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排序方式: 共有1882条查询结果,搜索用时 14 毫秒
21.
Thuluvath PJ Maheshwari A Jagannath S Arepally A 《Digestive diseases and sciences》2005,50(2):407-410
Primary prophylaxis with nonselective -blockers in high-risk subjects has been shown to be effective in reducing both esophageal variceal bleeding and mortality. Recently it has been suggested that band ligation may be a better option for primary prophylaxis. We compared nonselective -blockers with band ligation in patients with large varices (F2, F3) and elevated hepatic venous wedge pressure gradient (HVWPG, 12 mm Hg). All patients were prospectively followed for variceal bleeding, mortality, and treatment-related complications. Based on previous published studies, we estimated that 90 patients in each arm would be required to show a difference in bleeding rate. The study was prematurely terminated when we realized that our estimated sample size was inadequate to show a difference based on the observed bleeding rate. At the time of termination, 31 patients (Child A, 11; B, 14; C, 6), with a mean HVWPG of 19 ± 9.1 mm Hg, were randomized to either band ligation (group A; n = 16) or -blockers (group B; n = 15). Baseline demographics of both groups were similar and the mean follow-up period was 27.4 ± 12.9 months. During the follow-up, two patients in group A and one patient in group B had bleeding. Nine patients (29%; group A, six; group B, three; P = ns) died due to non-bleeding-related causes and five (16%) patients (group A, three; group B, two) underwent liver transplantation. Treatment-related complication were minimal in both groups. Despite the selection of high-risk patients, the observed bleeding rate was much lower than anticipated. Based on our observed bleeding rates, 424 patients would be required in each arm to show a difference between band ligation and -blocker therapy. 相似文献
22.
Cardiac arrhythmias including supraventricular tachycardia are commonly encountered during pregnancy. The case of a young Indian woman with recurrent attacks of supraventricular tachycardia during pregnancy which was managed with adenosine and verapamil is reported. The possible mechanisms of maternal and fetal complications are discussed. 相似文献
23.
Anita Mahapatra A. R. Aramya R. Manohar K. Latha 《Indian journal of pharmaceutical sciences》2015,77(5):650-654
Kaṣāya or decoction is an Ayurvedic dosage form, prescribed based on the stage of the disease according to the principles of Ayurveda. This dosage form is traditionally prepared fresh and consumed on the same day but for the sake of convenience; the process of preparation has been modified so that it can be stored with longer shelf life, easy availability and produced in large quantities. There is a need to understand the implications of this modification in terms of chemical changes. This work attempted to check the phytochemical profile of both freshly prepared decoction and commercially available decoction with reference to some analytical parameters like pH, total soluble solids, phenols, alkaloids, potassium and to assess the changes in the thin layer chromatography profiling of the decoction. The results showed that phenols and potassium are found to be two fold higher in freshly prepared decoction, compared to commercially available decoction diluted to dosage in practice (1:4 ratio). However, the total alkaloid content was found to be approximately ten fold higher in commercially available decoction. It was observed that the thin layer chromatography profile of decoctions was extracted into petroleum ether and chloroform was similar and consistent with different batches though the bands in commercially available decoction were slightly more intense compared to freshly prepared decoction. The total soluble solids in commercially available decoction were four times higher than freshly prepared decoction. The study reveals that there are differences in the phytochemical profiles of the freshly prepared decoction and commercially available decoction of the same formulation. However, the significance of these differences can be determined only by further clinical studies. On the other hand, the study lends support to the practice of diluting the commercially available decoction to make it equivalent to freshly prepared decoction. 相似文献
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25.
Bryant Lin Paul J. Wang Srijoy Mahapatra Munther Homoud Mark Link N.A. Mark Estes Amin Al‐Ahmad 《Annals of noninvasive electrocardiology》2005,10(2):142-145
Background: Morphologic identification of ectopic P‐waves from surface ECGs can be challenging, particularly when the P‐wave is buried in the QRST wave complex. Because ECGs are often available on paper and not digitally, we developed a method of subtracting the T‐wave from the buried P‐wave complex on paper ECGs. Methods: To validate our system, an atrial extrastimulus was introduced during and following the T‐wave. The ECGs were scanned and then transformed from an image format to a digital format. A computer algorithm digitally subtracted a QRST with no buried P‐wave from one with a buried P‐wave, thus resulting in an extracted P‐wave. The extracted P‐waves were compared to the nonburied P‐wave by determining correlation coefficients and by visual grading by two independent reviewers. Results: Visual grading comparing the buried P‐wave with the exposed paced P‐wave was 94%. The median correlation coefficient was 85%. Conclusions: An ectopic atrial P‐wave obscured by a coincident QRST wave complex can be accurately derived from printed ECG using this PC‐based system. Addition of this technique to the existing methods may aid in the localization and ablation of ectopic atrial foci. 相似文献
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Patients with mitral valve disease and extreme enlargement of the left atrium usually exhibit significant decrease in chamber size following corrective mitral valve surgery. We describe a patient in whom extreme right and left atrial enlargement developed, and progressed following mitral valve replacement, with no evidence of prosthetic valve malfunction or tricuspid valve disease. 相似文献
28.
Maladaptive daydreaming (MD) is an immersive fantasy activity that leads to distress and socio-occupational dysfunction. MD has many features suggestive of behavioural addiction, but research exploring the phenomenology of this clinical construct is limited. MD has also been purported to be a maladaptive strategy to cope with distress, but often leads to uncontrollable absorption in fantasy world, social withdrawal and neglected aspects of everyday life. In this paper, we report the case of a 16-year-old boy who developed internet gaming disorder and MD after experiencing cyberbullying from his peers. The patient engaged in vivid, fanciful imagery that lasted for hours, leading to social dysfunction and academic deterioration. Baseline assessment revealed a Maladaptive Daydreaming Scale-16 score of 65 (cut-off 50) and an Internet Gaming Test-20 score of 86 (cut-off 71). The patient was managed primarily with psychological intervention. The therapy focused on behaviour modification and cognitive restructuring. Patients in clinical setting should be questioned about MD when presenting with excessive use of technology or other forms of behavioural addictions. Further studies are necessary to determine the biopsychosocial factors of MD and its correlates. There is also a need to study treatment and management approaches for treating MD. 相似文献
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30.
Geetha Ramachandran A. K. Hemanth Kumar P. K. Bhavani T. Kannan S. Ramesh Kumar N. Poorana Gangadevi V. V. Banurekha L. Sekar N. Ravichandran G. Mathevan G. N. Sanjeeva Rajeshwar Dayal Soumya Swaminathan 《Antimicrobial agents and chemotherapy》2015,59(2):1162-1167
The objective of this report was to study the pharmacokinetics of rifampin (RMP), isoniazid (INH), and pyrazinamide (PZA) in HIV-infected children with tuberculosis (TB) treated with a thrice-weekly anti-TB regimen in the government program in India. Seventy-seven HIV-infected children with TB aged 1 to 15 years from six hospitals in India were recruited. During the intensive phase of TB treatment with directly observed administration of the drugs, a complete pharmacokinetic study was performed. Drug concentrations were measured by high-performance liquid chromatography. A multivariable regression analysis was done to explore the factors impacting drug levels and treatment outcomes. The proportions of children with subnormal peak concentrations (Cmax) of RMP, INH, and PZA were 97%, 28%, and 33%, respectively. Children less than 5 years old had a lower median Cmax and lower exposure (area under the time-concentration curve from 0 to 8 h [AUC0–8]) of INH (Cmax, 2.5 versus 5.1 μg/ml, respectively [P = 0.016]; AUC0–8, 11.1 versus 22.0 μg/ml · h, respectively [P = 0.047[) and PZA (Cmax, 34.1 versus 42.3 μg/ml, respectively [P = 0.055]; AUC0–8, 177.9 versus 221.7 μg/ml · h, respectively [P = 0.05]) than those more than 5 years old. In children with unfavorable versus favorable outcomes, the median Cmax of RMP (1.0 versus 2.8 μg/ml, respectively; P = 0.002) and PZA (31.9 versus 44.4 μg/ml, respectively; P = 0.045) were significantly lower. Among all factors studied, the PZA Cmax influenced TB treatment outcome (P = 0.011; adjusted odds ratio, 1.094; 95% confidence interval, 1.021 to 1.173). A high proportion of children with HIV and TB had a subnormal RMP Cmax. The PZA Cmax significantly influenced treatment outcome. These findings have important clinical implications and emphasize that drug doses in HIV-infected children with TB have to be optimized. 相似文献