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81.
Objective
Ipomoea genus is an excellent source of lysergol which is used as a hypotensive and psychrotopic analgesic. Microwave-assisted extraction (MAE) was employed to extract lysergol from Ipomoea seeds, and response surface methodology (RSM) was applied to predict optimum conditions for extraction. 相似文献82.
83.
Childhood leukaemia in areas with different radon levels: a spatial and temporal analysis using GIS 总被引:6,自引:2,他引:4
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OBJECTIVES—To evaluate the relation between exposure to ground radon levels and leukaemia among children using existing population and disease registers.
DESIGN—Ecological correlation study.
SETTING—The county of Östergötland in Sweden.
METHODS—Every child born in the county between 1979 and 1992 was mapped to the property centroid coordinates by linking addresses in the population and property registers. Population maps were overlaid with radon maps and exposure at birth and each subsequent year was quantified as high, normal, low or unknown. This was analysed with data from the tumour registry. Standardised mortality ratios (SMRs) were calculated using the age and sex specific rates for Sweden for the year 1995.
RESULTS—90 malignancies occurred among 53 146 children (498 887 person years) who formed the study population. SMRs for acute lymphatic leukaemia (ALL) among children born in high, normal and low risk areas were 1.43, 1.17 and 0.25 respectively. The relative risk for the normal risk group and high risk group as compared with the low risk group was 4.64 (95% CI 1.29, 28.26) and 5.67 (95% CI 1.06, 42.27). The association between ALL and continued residence at normal or high risk areas showed a similar trend. No association between radon risk levels and any other malignancy was seen.
CONCLUSION—Children born in and staying at areas where the risk from ground radon has been classified as low are less likely to develop ALL than those born in areas classified as normal and high risk.
相似文献
DESIGN—Ecological correlation study.
SETTING—The county of Östergötland in Sweden.
METHODS—Every child born in the county between 1979 and 1992 was mapped to the property centroid coordinates by linking addresses in the population and property registers. Population maps were overlaid with radon maps and exposure at birth and each subsequent year was quantified as high, normal, low or unknown. This was analysed with data from the tumour registry. Standardised mortality ratios (SMRs) were calculated using the age and sex specific rates for Sweden for the year 1995.
RESULTS—90 malignancies occurred among 53 146 children (498 887 person years) who formed the study population. SMRs for acute lymphatic leukaemia (ALL) among children born in high, normal and low risk areas were 1.43, 1.17 and 0.25 respectively. The relative risk for the normal risk group and high risk group as compared with the low risk group was 4.64 (95% CI 1.29, 28.26) and 5.67 (95% CI 1.06, 42.27). The association between ALL and continued residence at normal or high risk areas showed a similar trend. No association between radon risk levels and any other malignancy was seen.
CONCLUSION—Children born in and staying at areas where the risk from ground radon has been classified as low are less likely to develop ALL than those born in areas classified as normal and high risk.
相似文献
84.
S. P. S. Yadav G. S. Kohli U. Wig N. K. Jindal R. K. Yadav 《Indian journal of otolaryngology and head and neck surgery》1988,40(1):37
An extremely rare case of spontaneous rupture of laryngeal ventricle is presented. Surgical anatomy of ventricle and management
of the case is discussed. 相似文献
85.
Serum aliesterase levels have been estimated in 38 patients with head and neck cancer. The mean value was significantly lower than in controls. The decrease in activity was greater in patients with ulcerative growths and it progressed with advancement in the stage of cancer. With radiotherapy, a progressive and significant increase in serum aliesterase activity was observed. In patients with non-malignant growths the activity was comparable with that in controls. 相似文献
86.
87.
88.
Off-pump multivessel coronary artery surgery in high-risk patients 总被引:11,自引:0,他引:11
Meharwal ZS Mishra YK Kohli V Bapna R Singh S Trehan N 《The Annals of thoracic surgery》2002,74(4):S1353-S1357
BACKGROUND: Coronary artery bypass surgery on cardiopulmonary bypass is associated with significant morbidity and mortality, which may be more marked in high-risk patients. We evaluated our results of off-pump coronary artery bypass (OPCAB) in high-risk patients with multivessel coronary artery disease and compared them with results in similar patients who underwent operation on cardiopulmonary bypass. METHODS: A total of 1,075 patients who underwent OPCAB between October 1996 and June 2001 and who had one or more of the following risk factors were included in the study: poor left ventricular function (EF < or = 30%), advanced age (> 70 years), left main stenosis, acute myocardial infarction, and redo coronary artery surgery. These patients were compared with 2,312 similar patients who underwent coronary artery bypass grafting on cardiopulmonary bypass during the same period. Preoperative risk factors, intraoperative variables, and postoperative results were analyzed and compared between two groups. RESULTS: The average number of grafts was 3.0 +/- 0.4 and 3.2 +/- 0.3 in the off-pump (OPCAB) and on-pump (CCAB) groups, respectively. Hospital mortality was 3.2% and 4.5% in OPCAB and CCAB groups respectively (p = 0.109). Perioperative myocardial infarction, requirement of inotropic agents, stroke, and renal dysfunction were comparable in two groups. Intubation time (19 +/- 5 vs 24 +/- 6 hours, p < 0.001), mean blood loss (362 +/- 53 vs 580 +/- 66 mL, p < 0.001), atrial fibrillation (14.3 vs 19.7%, p < 0.001), and prolonged ventilation (4.6 vs 7.6%, p = 0.002) were less in OPCAB group. Intensive care unit stay (20 +/- 8 hours) and hospital stay (6 +/- 3 days) were significantly less in the OPCAB group (p < 0.001). CONCLUSIONS: Off-pump coronary artery surgery can be safely performed in high-risk patients with multivessel coronary artery disease. Operative mortality is comparable to that associated with on-pump surgery, and avoidance of cardiopulmonary bypass is associated with reduced postoperative morbidity in these patients. 相似文献
89.
David H Peters Manish Kohli Maya Mascarenhas Krishna Rao 《International journal for quality in health care》2006,18(6):437-445
OBJECTIVE: The objective was to test whether a decision support technology for non-physicians can increase health care utilization and quality. DESIGN: Before and after measurements were taken from a systematic random sample of patients and staff at randomly assigned intervention and control facilities. SETTING: The study took place at primary health facilities in rural Tamil Nadu, India. PARTICIPANTS: One thousand two hundred and eighty-six patients and 82 staff were interviewed. INTERVENTION: A computer-assisted decision support technology was introduced to assist with patient screening. MAIN OUTCOME MEASURES: Outcome measures included new patient visits per month, a Global Patient Assessment of Care Index, and health worker attitude variables. RESULTS: There was a difference of difference of 430 new patient visits per month at the intervention sites (P = 0.005), an increase from baseline of 18% at intervention sites compared with a decline of 5% at control sites. The intervention was associated with significant improvements in a Global Patient Assessment of Care Index (mean difference of difference 7.9, P < 0.001). The largest gains were made in patient communication, technical quality, and general satisfaction with care. The attitudes of public health workers toward the new technology and their jobs did not change. CONCLUSIONS: Decision support technologies have considerable potential to improve coverage and quality of health care for the poor and where there is no doctor, but the unreceptive attitude of public health workers would need to be overcome. Application of these technologies should take advantage of their popularity with patients and the opportunity to work through the private sector. 相似文献
90.
Gupta S Seith A Sud K Kohli HS Singh SK Sakhuja V Suri S 《Acta radiologica (Stockholm, Sweden : 1987)》2000,41(3):280-284
Purpose: We retrospectively reviewed the CT findings in 24 cases of autosomal dominant polycystic kidney disease (ADPKD) to assess the role of CT in the diagnostic work-up of patients with complicated ADPKD.Material and Methods: Twenty-four patients with ADPKD underwent unenhanced and contrast-enhanced CT for flank pain, haematuria, or fever. The images were retrospectively reviewed for presence of complicated cysts, their morphological features and associated findings in the perinephric space/retroperitoneum.Results: Cyst haemorrhage was present in all patients, seen as high-density cysts, which were mostly bilateral. Most of these cysts had sharply outlined contours, sharp interfaces with adjacent renal parenchyma, imperceptible walls, and homogeneous density, and did not enhance following i.v. contrast administration. However, a few haemorrhagic cysts (9 cysts in 6 patients) showed inhomogeneous density (n=7), dependent layering of high-density blood leading to fluid-fluid level (n=2), and contour irregularity (n=3).CT revealed presence of cyst infection in 6 cases; the involved cysts were larger (average size 4.2 cm) than adjacent cysts, had only a mildly increased or near water density, and showed wall thickening and enhancement. Other findings included air within the infected cyst (n=1), thickening and enhancement of peri- and paranephric fasciae (n=5), and abscesses in the posterior paranephric space and adjoining psoas muscle (n=2). In 2 other patients, although CT suggested cyst infection because of presence of wall enhancement, diagnostic needle aspiration revealed only sterile haemorrhagic fluid. In 1 case, CT revealed a soft tissue density enhancing mass in one of the cysts; this proved to be a renal cell carcinoma by fine-needle biopsy. Calculi were observed in 7 patients, and cyst wall calcification in 11 cases.Conclusion: A combination of unenhanced and contrast-enhanced CT allows correct diagnosis and differentiation amongst the various complications affecting patients with ADPKD. However, in a small subgroup of patients, it may not be possible to differentiate between haemorrhage and infection; such cases require diagnostic needle aspiration for diagnosis. 相似文献