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941.
PURPOSE OF REVIEW: With the graying of the world's population, there is an increased interest in the physiological effects of aging. This review examines the physiological changes of the gut with aging and their clinical significance. RECENT FINDINGS: Changes with aging in the gastrointestinal tract are variable, but in some cases they are responsible for a variety of symptoms. Thus, alterations in taste and smell, gastric motility, intestinal overgrowth and changes in gastrointestinal hormone release are the basis of the physiological anorexia of aging. Alterations in swallowing lead to silent aspiration. Changes in gastric emptying play a role in postprandial hypotension. Changes in gastrointestinal function can lead to constipation and fecal incontinence. Weakening of the colonic muscular wall produces diverticula. Achlorhydria is associated with malabsorption of some forms of iron and calcium. Vitamin D malabsorption aggravates the hypovitaminosis D that is so common in older persons. Changes in probiotics can lead to diarrhea and altered immune system. In the liver, aging is associated with delayed drug metabolism. SUMMARY: Changes in the physiology of the gut play a role in the anorexia of aging, aspiration pneumonia, postprandial hypotension, constipation and fecal incontinence. 相似文献
942.
943.
Ayesha Humayun Noor Fatima Shahid Naqqash Salwa Hussain Almas Rasheed Huma Imtiaz Sardar Zakariya Imam 《BMC medical ethics》2008,9(1):1-8
Background
The principles of informed consent, confidentiality and privacy are often neglected during patient care in developing countries. We assessed the degree to which doctors in Lahore adhere to these principles during outpatient consultations.Material & Method
The study was conducted at medical out-patient departments (OPDs) of two tertiary care hospitals (one public and one private hospital) of Lahore, selected using multi-stage sampling. 93 patients were selected from each hospital. Doctors' adherence to the principles of informed consent, privacy and confidentiality was observed through client flow analysis performed by trained personnel. Overall patient perception was also assessed regarding these practices and was compared with the assessment made by our data collectors.Results
Some degree of informed consent was obtained from only 9.7% patients in the public hospital and 47.8% in the private hospital. 81.4% of patients in the public hospital and 88.4% in the private hospital were accorded at least some degree of privacy. Complete informational confidentiality was maintained only in 10.8% and 35.5% of cases in public & private hospitals respectively. Informed consent and confidentiality were better practiced in the private compared to the public hospital (two-sample t-test > 2, p value < 0.05). There was marked disparity between the patients' perspective of these ethical practices and the assessment of our trained data collectors.Conclusion
Observance of medical ethics is inadequate in hospitals of Lahore. Doctors should be imparted formal training in medical ethics and national legislation on medical ethics is needed. Patients should be made aware of their rights to medical ethics. 相似文献944.
945.
Dionysios Trigkilidas Surjit Lidder David Delaney Rob C. Pollock Asif Saifuddin 《Skeletal radiology》2009,38(11):1115-1118
Neuritis ossificans is an extremely rare reactive process affecting peripheral nerves, which can be challenging to diagnose and treat. Magnetic resonance imaging (MRI) is an excellent imaging modality for these lesions, showing inflammatory reaction around the nerve. Only a few cases have been previously reported, and all of the patients underwent surgical resection. In this article we report the first case of neuritis ossificans affecting the common peroneal nerve, treated non-operatively, and we review the literature. 相似文献
946.
Asif A. Wani Sohit Kanotra Mohammad Lateef Rafiq Ahmad Sajad M. Qazi Shawkat Ahmad 《Indian journal of otolaryngology and head and neck surgery》2009,61(3):163-168
Introduction
Functional endoscopic sinus surgery (FESS) has revolutionized the approach and treatment of chronic rhinosinusitis. Certain anatomical variations are thought to be predisposing factors for the development of sinus disease and it is necessary, for the surgeon to be aware of these variations, especially if the patient is a candidate for FESS.Objective
The aim of the present study was to identify the various anatomical variations of the ostiomeatal complex in patients of chronic rhinosinusitis who underwent FESS.Materials and methods
A total of 150 patients of chronic rhinosinusitis (medical treatment failures) who were subjected to FESS were CT scanned preoperatively to find any bony anatomic variation and the extent of mucosal disease.Results
Concha bullosa was the commonest anatomic variation and was seen in 45 (30%) patients. The other anatomic variations noted included: paradoxical middle turbinate in 9.33% patients, uncinate process variations in 25% patients, agger nasi cells in 9.33%, Haller cells in 8.66% and posterior septal deviations in 25.33% patients. The mucosal disease was most commonly seen in anterior ethmoids (87.33% ), followed by maxillary sinus ostial area (70%), maxillary sinus disease (65.33%), posterior ethmoidal disease (38%), frontal sinus disease (15%) and sphenoid sinus mucosal disease (8.66%) patients.Conclusion
A thorough preoperative CT evaluation of the patients undergoing FESS is necessary to detect various anatomical variations in the ostiomeatal complex. 相似文献947.
948.
Chang SC Rashid A Gao YT Andreotti G Shen MC Wang BS Han TQ Zhang BH Sakoda LC Leitzmann MF Chen BE Rosenberg PS Chen J Chanock SJ Hsing AW 《Carcinogenesis》2008,29(5):944-948
Biliary tract cancer, encompassing tumors of the gallbladder, extrahepatic bile ducts and ampulla of Vater, is a rare but highly fatal malignancy. Obesity and gallstones, both related to insulin resistance, are linked to an elevated risk of biliary cancer. The peroxisome proliferator-activated receptors (PPARs) and the retinoid X receptors (RXRs), expressed in adipose tissue, play a key role in the regulation of obesity-related insulin sensitivity, thus genetic variants of these two receptor genes may be related to biliary cancer and stones. We examined the associations of seven single-nucleotide polymorphisms in the PPAR-gamma, PPAR-delta, RXR-alpha, RXR-beta and INS genes with biliary cancer and stones in a population-based case-control study in Shanghai, China. We included 237 gallbladder, 127 extrahepatic bile duct and 47 ampulla of Vater cancer cases, 895 stone cases and 786 population controls. Relative to individuals with the RXR-beta C51T (rs2076310) CC genotype, those having the TT genotype had a 1.6-fold risk for bile duct cancer [odds ratio (OR) = 1.67; 95% confidence interval (CI) = 0.99-2.84], with a more pronounced association among men (OR = 2.30; 95% CI = 1.14-4.65; P interaction = 0.07). This marker was also associated with a higher risk of gallstones among subjects with a higher body mass index (BMI) (>or=23 kg/m(2)) (OR = 1.80; 95% CI = 1.09-2.94), although the interaction with BMI was not statistically significant (P interaction = 0.28). No association was found between other variants and biliary cancers and stones. Results from this population-based study suggest that certain genetic variants involved in the regulation of obesity-related insulin sensitivity may increase susceptibility to bile duct cancer and gallstones. 相似文献
949.
Interleukin-1beta is up-regulated in the presence of Helicobacter pylori infection. H. pylori infection was associated with E-cadherin methylation. In this study, we examined if IL-1beta could induce promoter methylation of E-cadherin in human gastric cancer cell lines TMK-1, MKN-74 and MKN-7. Cells were treated with IL-1beta (0.025, 0.1, 0.25, 1.0, 2.5 ng/mL) for 6, 12 and 24h. Methylation status was determined by MSP and sequencing. The effects of IL-1beta or H.pylori on the cells, and after blockade with interleukin-1 receptor antagonist (IL-1ra) were tested. Promoter methylation of E-cadherin was induced in all three cells treated with IL-1beta or co-cultured with H. pylori. Treatment of IL-1ra could reverse the phenomena. Our study indicated that IL-1beta is an important step in mediating E-cadherin methylation. 相似文献
950.
Harsolia A Hugo GD Kestin LL Grills IS Yan D 《International journal of radiation oncology, biology, physics》2008,70(2):582-589
PURPOSE: This study compares multiple planning techniques designed to improve accuracy while allowing reduced planning target volume (PTV) margins though image-guided radiotherapy (IGRT) with four-dimensional (4D) cone-beam computed tomography (CBCT). METHODS AND MATERIALS: Free-breathing planning and 4D-CBCT scans were obtained in 8 patients with lung tumors. Four plans were generated for each patient: 3D-conformal, 4D-union, 4D-offline adaptive with a single correction (offline ART), and 4D-online adaptive with daily correction (online ART). For the 4D-union plan, the union of gross tumor volumes from all phases of the 4D-CBCT was created with a 5-mm expansion applied for setup uncertainty. For offline and online ART, the gross tumor volume was delineated at the mean position of tumor motion from the 4D-CBCT. The PTV margins were calculated from the random components of tumor motion and setup uncertainty. RESULTS: Adaptive IGRT techniques provided better PTV coverage with less irradiated normal tissues. Compared with 3D plans, mean relative decreases in PTV volumes were 15%, 39%, and 44% using 4D-union, offline ART, and online ART planning techniques, respectively. This resulted in mean lung volume receiving > or = 20Gy (V20) relative decreases of 21%, 23%, and 31% and mean lung dose relative decreases of 16%, 26%, and 31% for the 4D-union, 4D-offline ART, and 4D-online ART, respectively. CONCLUSIONS: Adaptive IGRT using CBCT is feasible for the treatment of patients with lung tumors and significantly decreases PTV volume and dose to normal tissues, allowing for the possibility of dose escalation. All analyzed 4D planning strategies resulted in improvements over 3D plans, with 4D-online ART appearing optimal. 相似文献