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Tushar M Ranchod Daynia E Ballot Alma M Martinez Barbara J Cory Victor A Davies J Colin Partridge 《Suid-Afrikaanse tydskrif vir geneeskunde》2004,94(11):913-916
BACKGROUND: Little is known about parental experience and decision making with regard to premature infants requiring intensive care in developing countries. We undertook this study to characterise parents' experience of physician counselling and their role in making life-support decisions for very low-birth-weight (VLBW) (birth weight < 1 501 g) infants born in South Africa's public-sector neonatal intensive care units (NICUs). METHODS: Parents of surviving VLBW infants treated in three Johannesburg-area public hospitals and attending follow-up clinics in August 2001 were interviewed regarding their experience of perinatal counselling on outcomes (pain, survival, disability), perception of actual and optimal decision making, and satisfaction with NICU communication. RESULTS: Parents of 51 infants were interviewed. Seventy-five per cent of parents reported antenatal counselling by physicians on at least one perinatal topic (severe disability, pain, death, finances or religious/moral considerations). The majority of parents (> 60%) who received counselling thought that these topics had been discussed adequately. Most parents reported that doctors had the primary decision-making role, either without consulting them (41%) or after consulting them (37%). Joint decision making was rare (14%). Parents wanted more input in life-support decisions than they reported being given. CONCLUSION: Counselling is not consistently provided in public-sector hospitals in Johannesburg. Parents of premature infants want a larger share in NICU decision making than they currently experience. Most parents were satisfied with communication later during their infant's hospitalisation. South Africa presents a unique opportunity to study the use of advanced medical technologies in a nation with marked disparities in access to care. 相似文献
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Primary care referrals for lumbar spine radiography: diagnostic yield and clinical guidelines.
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William Hollingworth Christopher J Todd Hugh King Tony Males Adrian K Dixon Kanti R Karia Ann Louise Kinmonth 《The British journal of general practice》2002,52(479):475-480
BACKGROUND: Primary care requests for radiographs of the lumbar spine have come under increasing scrutiny. Guidelines aiming to reduce unnecessary radiographs by limiting referrals to patients at high risk of serious disease have been widely distributed. Trial evidence suggests that guidelines can reduce radiography referrals. It is not clear whether this reduction has been achieved in routine practice. AIM: This study, using routine data, was conducted to measure trends in pnmary care referrals for lumbar spine radiography at two hospitals between 1994 and 1999. DESIGN OF STUDY: Analysis of primary care requests for lumbar spine radiography from computerised records. SETTING: Addenbrooke's Hospital, Cambridge (1 July 1994 to 30 June 1999), and Ipswich General Hospital (1 July 1995 to 30 June 1999), United Kingdom. METHOD: All primary care requests for lumbar radiography were identified electronically from computerised information systems. A random sample of 2100 radiography reports were classified according to clinical importance. These classifications were used to examine whether the proportion of radiographs demonstrating potentially more serious findings had increased between 1994 and 1999. RESULTS: There was no evidence that primary care referrals for radiography of the lumbar spine had decreased between 1994 and 1999 at either hospital. General practitioners did not progressively refer more high-risk patients for lumbar radiography. Only a small proportion of patients had important radiographic findings that might warrant specialist referral or specific therapy. CONCLUSION: The implementation of diagnostic guidelines offers much to the NHS. However in these two hospitals, the reduction in radiograph utilisation evident in trials was not achieved. Guideline development is a resource intensive process; distribution must be supported by more effective implementation strategies. 相似文献
4.
Evaluation of active and passive transport processes in corneas extracted from preserved rabbit eyes
Soumyajit Majumdar Tushar Hingorani Ramesh Srirangam 《Journal of pharmaceutical sciences》2010,99(4):1921-1930
In vitro transcorneal permeability studies are an important screening tool in drug development. The objective of this research is to examine the feasibility of using corneas isolated from preserved rabbit eyes as a model for permeability evaluation. Eyes from male New Zealand White rabbits were used immediately or were stored overnight in phosphate-buffered saline (PBS) or Hanks balanced salt solution (HBSS) over wet ice. Integrity of isolated corneas was evaluated by measuring the TEER and by determining the permeability of paracellular and transcellular markers. Active transport was assessed by measuring transcorneal permeability of selected amino acids. Esterase activity was estimated using p-nitrophenyl assay. In all cases, corneas from freshly enucleated eyes were compared to those isolated from the day-old preserved eyes. Transcellular and paracellular passive diffusion was not affected by the storage medium and observed to be similar in the fresh and preserved eye models. However, amino acid transporters demonstrated lower functional activity in corneas excised from eyes preserved in PBS. Moreover, preserved eyes displayed almost 1.5-fold lower esterase activity in the corneal tissue. Thus, corneas isolated from day-old eyes, preserved in HBSS, closely mimics freshly excised rabbit corneas in terms of both active and passive transport characteristics but possesses slightly reduced enzymatic activity. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99: 1921–1930, 2010 相似文献
5.
Tushar K. Chatterjee Rajat K. Das Santi R. Palit 《Macromolecular chemistry and physics.》1971,141(1):43-53
The aqueous polymerisation of methyl methacrylate initiated by the chromate/arsenite system has been studied. It is observed that the polymerisation by the above redox system is catalysed by OH? though the parent reaction between chromate and arsenite is catalysed by H⊕. It is also observed that traces of Cu2⊕ inhibit both the polymerization reaction as also the parent reaction. From these observations it is concluded (1) intermediate valency states of chromium has no initiating power in alkali solution and (2) the redox reaction between chromate and arsenite is a chain reaction involving single electron transfer and the intermediate As4⊕ thus produced is the initiating species. 相似文献
6.
Varma TK Lin CY Toliver-Kinsky TE Sherwood ER 《Clinical and diagnostic laboratory immunology》2002,9(3):530-543
Gamma interferon (IFN-gamma) is an important mediator of endotoxin (lipopolysaccharide [LPS])-induced immune responses. However, the specific cell types that produce IFN-gamma in response to LPS and the cellular factors that regulate LPS-induced IFN-gamma production have not been fully determined. The present studies were undertaken to characterize the cell populations that produce IFN-gamma after LPS challenge in the spleens of mice and to determine the regulatory factors that modulate LPS-induced production of IFN-gamma. Our studies show that the levels of splenic IFN-gamma mRNA and protein production peak at 6 and 8 h, respectively, after systemic LPS challenge. Approximately 60% of IFN-gamma-producing cells are natural killer (NK) cells (CD3(-)DX5(+)) and 25% are NKT cells (CD3(+)DX5(+)). Most of the remaining IFN-gamma-producing cells are T cells (CD3(+)DX5(-)), macrophages, and dendritic cells. Functionally, interleukin-12 (IL-12) is the major IFN-gamma-stimulating factor after LPS challenge, with costimulation provided by IL-15, IL-18, and B7 proteins. IL-10 is a major inhibitor of LPS-induced IFN-gamma production. Unlike intact heat-killed gram-negative and gram-positive bacteria, the class II major histocompatibility complex did not play a functional role in LPS-induced IFN-gamma production. LPS is a potent stimulus for splenic IL-10, IL-12 p40, and IL-15 mRNA expression, whereas IL-12 p35 and IL-18 mRNAs, as well as B7 proteins, are constitutively expressed in the mouse spleen. Of the factors studied, IL-18 serves as the most potent costimulus with IL-12 for IFN-gamma production, followed by IL-15 and B7 proteins. These data demonstrate that NK cells and NKT cells are the most abundant IFN-gamma-producing cells in the mouse spleen after LPS challenge and that IL-10 and IL-12 are key functional regulators of LPS-induced IFN-gamma production. 相似文献
7.
John C Byrd Bercedis L Peterson Janice Gabrilove Olatoyosi M Odenike Michael R Grever Kanti Rai Richard A Larson 《Clinical cancer research》2005,11(11):4176-4181
PURPOSE: Flavopiridol has in vitro activity in chronic lymphocytic leukemia (CLL) and promotes apoptosis independent of p53 function or prior fludarabine exposure. We sought to determine if flavopiridol has activity in previously treated CLL using two schedules of administration. PATIENTS AND METHODS: Patients with previously treated CLL were enrolled in two sequentially done phase II studies. Patients in the first trial received flavopiridol (50 mg/m(2)/d) as a continuous infusion (CI) for 72 hours every 2 weeks. Patients in the second trial received flavopiridol 50 mg/m(2) as a 1-hour bolus (IVB) daily for 3 days repeated every 3 weeks. Patients received up to 12 (CI cohort) or 8 (IVB cohort) cycles of therapy. RESULTS: Fifteen patients were enrolled in the 72-hour CI phase II trial; 6 (40%) had intermediate-risk (Rai stage I or II) and 9 (60%) had high-risk (Rai stage III and IV) stages. No responses were noted in this group; 27% had stable disease and 73% had progressive disease. Thirty-six patients were enrolled in the second IVB trial, with 13 (36%) having intermediate and 23 (64%) having high-risk disease. Four patients (11%) had partial responses, 19 (53%) had stable disease, and 13 (36%) had progressive disease. The progression-free survival for responders in the IVB trial was 3, 3, 9, and 19 months. The median progression-free survival was 2 months [95% confidence interval (95% CI), 1.8-3.8] for patients in the CI trial and 3 months (95% CI, 2.5-7.4) for the IVB trial. The median overall survival was 27 months (95% CI, 20-42) for the CI trial and 24 months (95% CI, 18-31) for the IVB trial. Toxicity was manageable and included mainly myelosuppression, infections, diarrhea, and fatigue. CONCLUSIONS: Flavopiridol has modest, schedule-dependent clinical activity in relapsed CLL and warrants future investigation utilizing alternative schedules of administration. 相似文献
8.
Malaya Gupta Upal Kanti Mazumder Ramanathan Sambath Kumar Thangavel Siva Kumar 《Acta pharmacologica Sinica》2004,25(8):1070-1076
AIM: To study the antitumor effect and antioxidant role of Bauhinia racemosa. METHODS: Antitumor activity and antioxidant status of methanol extract (50, 100, and 200 mg/kg) of Bauhinia racemosa stem bark was evaluated against Ehrlich ascites carcinoma (EAC) tumor in mice. Acute and short-term toxicity studies were performed initially in order to ascertain the safety of methanol extract of Bauhinia racemosa (MEBR). After 24 h of tumor inoculation, the extract was administered daily for 14 d. After administration of the last dose followed by 18 h fasting, mice were then sacrificed for observation of antitumor activity. The effect of MEBR on the growth of transplantable murine tumor, life span of EAC bearing hosts and simultaneous alterations in the hematological profile and liver biochemical parameters (lipid peroxidation, antioxidant enzymes) were estimated. RESULTS: The MEBR showed decrease in tumor volume, packed cell volume and viable cell count, and increased the nonviable cell count and mean survival time thereby increasing life span of EAC tumor bearing mice. Hematological profile reverted to more or less normal levels in extract treated mice. Treatment with MEBR decreased the levels of lipid peroxidation and increased the levels of glutathione, superoxide dismutase and catalase. CONCLUSION: The methanol extract of Bauhinia racemosa stem bark exhibited antitumor effect by modulating lipid peroxidation and augmenting antioxidant defense system in EAC bearing mice. 相似文献
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