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91.
Spinal intramedullary ependymal cyst. Report of two cases and review of the literature 总被引:1,自引:0,他引:1
Two pediatric patients (4 and 5 years of age) with spinal intramedullary ependymal cysts located at the cervical and dorsal cord are reported here. One patient was admitted with subtle signs, while the other had disabling spastic quadriparesis. In both patients, MRI depicted a well-demarcated, localized, nonenhancing intramedullary lesion isointense with CSF on T(1)- and T(2)-weighted images. Total excision of the covering membrane of the cyst was not possible in either case. The child with spastic quadriparesis had a remarkable recovery, while the subtle signs of the other patient regained normalcy at the follow-up of 4 and 5 months, respectively. 相似文献
92.
Mononuclear phagocytes can be activated through an immunoglobulin E (IgE)- specific mechanism to release pro-inflammatory cytokine like interleukin-1beta (IL-1beta). The present study was conducted to show the inter-relationship between these two parameters in the serum of asthmatic patients. The study included 30 patients of asthma and 10 as control. Out of these 30 cases, 20 patients had stable and 10 had acute asthma. Of the 20 stable patients, 9 were allergic and 11 were non-allergic to either of the 12 allergens used for skin prick test. Serum IgE and IL-1beta levels were measured by enzyme linked immunosorbent assay (ELISA). Total serum IgE levels increased significantly (p < 0.05) in asthma [200.5 +/- 30.91 IU/ml, mean +/- standard error of mean (SEM)] in comparison with the controls (18.15 +/- 4.35 IU/ml). Serum IL-1beta level was higher in allergic (1.94 +/- 0.63 pg/ml) than in non-allergic patients (0.64 +/- 0.21 pg/ml) but it was not statistically significant (p > 0.05). The study suggests involvement of IgE and IL-1beta in the pathophysiology of allergic asthmatic condition. Further studies are required to delineate the inflammatory pathway in asthma and determine stages at which therapeutic interventions can be done. 相似文献
93.
Preoperative diagnosis of allergic fungal sinusitis 总被引:4,自引:0,他引:4
Dhiwakar M Thakar A Bahadur S Sarkar C Banerji U Handa KK Chhabra SK 《The Laryngoscope》2003,113(4):688-694
OBJECTIVES/HYPOTHESIS: Although the diagnosis of allergic fungal sinusitis is mainly based on characteristic histopathological findings, certain preoperative diagnostic criteria have been proposed. However, their usefulness in differentiating allergic fungal sinusitis from other sinus diseases is unknown. The objective of the study was to identify accurate preoperative diagnostic parameters for allergic fungal sinusitis. STUDY DESIGN: Prospective, comparative study. METHODS: Twenty consecutive cases of allergic fungal sinusitis were evaluated prospectively and compared with 16 cases of ethmoidal polyposis and 5 cases of invasive sinus aspergillosis, with regard to various clinical, radiological, and immunological parameters. All patients were categorized based on histopathological findings. RESULTS: Nasal polyps were seen in all 20 cases of allergic fungal sinusitis, all 16 cases of ethmoidal polyposis, and 2 of 5 cases of invasive sinus aspergillosis. Computed tomography (CT) scan hyper-attenuation was seen in all 20 cases of allergic fungal sinusitis but also in 2 (13%) cases of ethmoidal polyposis and 2 (40%) cases of invasive sinus aspergillosis. Serum levels of specific anti-Aspergillus immunoglobulin E were elevated in 14 (70%) cases of allergic fungal sinusitis, 2 (13%) cases of ethmoidal polyposis, and 3 (60%) cases of invasive sinus aspergillosis. The combination of all three (ie, nasal polyps, CT scan hyper-attenuation, and elevated titers of anti-Aspergillus immunoglobulin) was not found in any case of ethmoidal polyposis or invasive sinus aspergillosis. This triad demonstrated a sensitivity of 70% and a specificity of 100% for the preoperative diagnosis of allergic fungal sinusitis. CONCLUSIONS: Nasal polyps, CT scan, and specific immunoglobulin E titers, when considered in combination, have a high preoperative diagnostic value in allergic fungal sinusitis. However, they should not be considered in isolation because considerable overlap occurs with invasive sinus aspergillosis and ethmoidal polyposis. 相似文献
94.
Hypertension is essentially the elevation of arterial blood pressure beyond an arbitrary cut off point, though the dividing line between normal and elevated BP is lacking. Hypertension can be classified into primary, essential or idiopathic hypertension on one hand, and secondary one due to some disease itself. In treating hypertension, antihypertensives have their role, but attention may be directed towards some lifestyle modifications. As regarding dietary interventions, calorie restriction may influence the minimisation of BP. Body weight reduction, less alcohol consumption, salt restriction, potassium and calcium supplementation can enhance the process of lowering BP. The role of magnesium in hypertension is debatable. Serum cholesterol level is commonly elevated in hypertensive patients and its reduction reduces the risk of non-fatal coronary events. Diet rich in plant fibres either alone or with a low fat, low sodium could lower the BP by about 5 mm Hg in hypertensives. The omega-3-polyunsaturated fatty acids found in highest concentrations in cold water fishes have a modest antihypertensive effect. Caffeine contained in two cups of coffee may raise the BP by 5 mm Hg in infrequent users but in habitual users, caffeine has no role. Deficiency of vitamin C might lead to hypertension. As regarding behavioural changes, stopping smoking, regular physical exercise, relaxation therapies like yoga, etc, have definite beneficial effect on hypertensives. The antihypertensive effect of lifestyle modifications may obviate drug therapy. For this one or more of the lifestyle modifications should be tried initially in all hypertensive patients. 相似文献
95.
The authors conducted a cross-sectional study among residents of Delhi to determine the role of ambient air pollution in chronic respiratory morbidity in Delhi. The authors selected a random, stratified sample (N = 4,171) of permanent residents who were 18+ y of age and who lived near 1 of the 9 permanent air quality monitoring stations in the city. Air-quality data for the past 10 y were obtained; data were based on the differences in total suspended particulates, and the study areas were categorized into lower- and higher-pollution zones. A standardized questionnaire was administered, clinical examination was carried out, and spirometry followed. The authors assessed chronic respiratory morbidity by (a) prevalence of chronic respiratory symptoms (i.e., chronic cough, phlegm, breathlessness, and wheezing) and airway diseases (i.e., chronic obstructive pulmonary disease/chronic bronchitis and bronchial asthma); and (b) lung function results in asymptomatic nonsmoking subjects in the two pollution zones. A multiple logistic regression identified the determinants of chronic symptoms. Smoking, male sex, increasing age, and lower socioeconomic status were strong independent risk factors for occurrence of chronic respiratory symptoms. In the comparison of nonsmoking residents of lower- and higher-pollution zones--stratified according to socioeconomic levels and sex--chronic cough, chronic phlegm, and dyspnea (but not wheezing) were significantly more common in the higher-pollution zone in only some of the strata. Furthermore, prevalence rates of bronchial asthma, chronic obstructive pulmonary disease, and chronic bronchitis among residents in the two pollution zones were not significantly different. Nonetheless, lung function of asymptomatic nonsmokers was consistently and significantly better among both male and female residents of the lower-pollution zone. 相似文献
96.
Gardiner SM Chhabra SR Harty C Williams P Pritchard DI Bycroft BW Bennett T 《British journal of pharmacology》2001,133(7):1047-1054
N-acylhomoserine lactones (AHLs) are small, diffusible signalling molecules, employed by Gram-negative bacteria to coordinate gene expression with cell population density. Recent in vitro findings indicate that AHLs may function as virulence determinants per se, through modification of cytokine production by eukaryotic cells, and by stimulating the relaxation of blood vessels. In the present study, we assessed the influence of AHLs on cardiovascular function in conscious rats, and draw attention to the ability of the N-(3-oxododecanoyl)-L-homoserine lactone (3-oxo-C12-HSL), a signal molecule produced by P. aeruginosa, to cause marked bradycardia. This bradycardic effect was blocked by atropine and atenolol, and did not occur in vitro. Furthermore, modification of the acyl side chain length resulted in the loss of activity, whereas removal of the homoserine lactone ring, did not. The bradycardic effect of 3-oxo-C12-HSL was also observed in endotoxaemic animals, albeit attenuated. In normal rats, 3-oxo-C12-HSL caused initial mesenteric and hindquarters vasoconstriction, but only slight, and delayed signs of vasodilatation in the renal and mesenteric vascular beds. Furthermore, administration of 3-oxo-C12-HSL (pre-treatment or 2 h post-treatment) together with LPS, did not modify the established regional haemodynamic effects of the LPS, 6 h after the onset of its infusion. Our observations do not provide any clear evidence for an ability of 3-oxo-C12-HSL to modify the haemodynamic responses to LPS infusion. However, they are not inconsistent with the hypothesis that some of the cardiovascular sequelae of bacterial infection may be modulated by an influence of bacterial quorum sensing signalling molecules on the host. 相似文献
97.
Cranial subdural haematoma after spinal anaesthesia 总被引:1,自引:0,他引:1
Intracranial subdural haematoma is an exceptionally rare complicationof spinal anaesthesia. A 20-yr-old male underwent appendicectomyunder partial spinal and subsequent general anaesthesia. A weeklater, he presented with severe headache and vomiting not respondingto bed rest and analgesia. Magnetic resonance imaging showeda small acute subdural haematoma in the right temporo-occipitalregion. The patient improved without surgical decompression.The pathogenesis of headache and subdural haematoma formationafter dural puncture is discussed and the literature brieflyreviewed. Severe and prolonged post-dural puncture headacheshould be regarded as a warning sign of an intracranial complication. Br J Anaesth 2001; 86: 8935 相似文献
98.
S Chhabra 《Journal of obstetrics and gynaecology》2007,27(5):460-463
Globally, women suffer due to violence. Violence during pregnancy is being increasingly recognised as a clinical as well as public health problem. The objectives of the present study were: to find out the extent and causes of violence during pregnancy; the relation of violence with, age, education, occupation; and to study the immediate effects of violence during pregnancy. A total of 2,000 pregnant women (health seekers or their friends or relatives) irrespective of age and socioeconomic status, were interviewed using a pre-designed, semistructured, pre-tested questionnaire in local language, with some open-ended questions. Out of the 2,000 pregnant women interviewed, 952 (47.6%) had been physically hit or slapped or kicked, at some time during pregnancy, many repeatedly. Though more teenagers (65.63%) and illiterate women (70.32%) were assaulted, those with a postgraduate education (41.08%) had also suffered. A total of 71.7% had been hit by their husbands - 32.4% were hit on the back and 161 (16.9%) on abdomen. Of the women who were assaulted during pregnancy, 30.25% had also suffered violence when non-pregnant. The present study reveals that violence is a common problem during pregnancy. While attempts need to be made to prevent this, it is essential that the healthcare providers who manage these women are aware of the possibility. 相似文献
99.
G. K. Malik M.D. D.C.H. D. K. Chhabra M.S. M. Ch. R. Shukla M.D. M.N.A.M.S. B. Sharma M.D. D.C.H. 《Indian journal of pediatrics》1981,48(2):169-174
Cerebral angiography was performed in 34 children having sudden hemiplegia of obscure orgin. Arterial occlusions were detected in 61.7%. Occlusions were seen more often in cases where angiography was done early in the course of illness. The involvement of internal carotid artery with middle cerebral artery and/or anterior cerebral artery was most common. Arteritis was the suggested etiology of occlusion. 相似文献
100.
Chhabra SK Anderson LM Perella C Desai D Amin S Kyrtopoulos SA Souliotis VL 《Toxicology and applied pharmacology》2000,169(2):191-200
Use of alcoholic beverages increases risk of cancer at several target sites, including the breast. Of several possible mechanisms for this effect, competitive inhibition by ethanol of hepatic clearance of nitrosamines, resulting in increased dose delivery to posthepatic tissues, gives the quantitatively most pronounced enhancement. We investigated whether this effect would pertain to the mammary gland, and to ethanol and nitrosamines delivered translactationally to sucklings. Ethanol (1.6 g/kg) was administered by gavage to nursing Sprague-Dawley rats 10 min before 5 mg/kg N-nitrosodimethylamine (NDMA) or 50 mg/kg 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK); treatment was on postnatal days 1, 7, or 14. Tissues taken 4 h later for analysis of O(6)-methylguanine in DNA were liver, blood, and mammary glands from the mothers, and liver, lung, kidney, and blood from the sucklings. Ethanol cotreatment resulted in a marked, 10-fold increase in O(6)-methylguanine adducts from NDMA in mammary gland, as well as smaller but significant increases in this tissue from NNK and in maternal blood cells from both chemicals; adducts in maternal liver decreased slightly. In the sucklings, ethanol cotreatment also lowered adducts in liver after NDMA or NNK treatment. After NDMA, adducts were also detected in suckling lung and kidney and were increased five- to 10-fold after ethanol coexposure. Adducts from either chemical, with or without ethanol, decreased markedly in all suckling tissues with development from postnatal day 1 to day 14. Thus ethanol coexposure with nitrosamines increases O(6)-methylguanine DNA adducts in mammary gland and strongly influences adduct formation in suckling tissues after translactational delivery. 相似文献