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排序方式: 共有1070条查询结果,搜索用时 18 毫秒
71.
72.
Hafeez S Majeed I 《Journal of the College of Physicians and Surgeons--Pakistan : JCPSP》2004,14(1):48-49
Snakebite cases may have myriad presentations. we are describing a previously healthy young man presenting within half an hour of snakebite who experienced abrupt fatal cardiac rhythm changes ranging from bradycardia to ventricular tachycardia/fibrillation over a short span of time. 相似文献
73.
Background
There are multiple studies in different countries regarding the prevalence of vitamin D deficiency. These studies showed high prevalence of vitamin D deficiency in Asian countries. This study tries to elucidate the prevalence of vitamin D deficiency and its influencing factors in population of Tehran.Methods
1210 subjects 20–64 years old were randomly selected. 25 (OH) D serum levels were measured. Duration of exposure to sunlight, the type of clothing and level of calcium intake and BMI were quantified based on a questionnaire.Results
A high percentage of vitamin D deficiency was defined in the study population. Prevalence of severe, moderate and mild Vitamin D deficiency was 9.5%, 57.6% and 14.2% respectively. Vitamin D serum levels had no significant statistical relation with the duration of exposure to sunlight, kind of clothing and BMI. Calcium intake in the normal vitamin D group was significantly higher than the other groups (714.67 ± 330.8 mg/day vs 503.39 ± 303.1, 577.93 ± 304.9,595.84 ± 313.6). Vitamin D serum levels in young and middle aged females were significantly lower than the older group.Conclusions
Vitamin D deficiency has a high prevalence in Tehran. In order to avoid complications of vitamin D deficiency, supplemental dietary intake seems essential. 相似文献74.
Ashworth M Lea R Gray H Rowlands G Gravelle H Majeed A 《Journal of public health (Oxford, England)》2004,26(1):48-51
METHODS: Primary care organizations (PCOs) in England are required to run a prescribing incentive scheme. The average payment received by general practitioners (GPs) under these schemes is not known. We conducted a longitudinal (2 year) questionnaire study of all PCOs in London and the south east of England aiming to explore the relationship between the financial incentives, the selection of prescribing indicators and success at remaining within budget. In the second year, the average reward per GP amounted to 1220 pounds (range 470 pounds-4330 pounds). Underspent PCOs made larger incentive scheme payments to their practices as did PCOs that had successfully overturned a first year overspend into a second year underspend. The size of rewards was unrelated to the selection of any particular cost- or quality-based prescribing indicator. We conclude that larger prescribing incentive scheme payments may have contributed to prescribing cost control but their effect on prescribing quality is uncertain. 相似文献
75.
Nimeri G Majeed M Elwing H Ohman L Wetterö J Bengtsson T 《Journal of biomedical materials research. Part A》2003,67(2):439-447
The interaction between neutrophil granulocytes and platelets is considered to play an important role in the inflammatory process induced by an implanted foreign material. However, the cellular mechanisms involved remain incompletely understood. We used a luminol-dependent chemiluminescence (CL) technique to analyze the generation of reactive oxygen species (ROS) in human neutrophils interacting with different plasma protein-coated surfaces in the presence or absence of unstimulated or stimulated platelets. The role of tyrosine phosphorylation in the regulation of NADPH oxidase activity was evaluated with quantitative fluorescence microscopy and the specific tyrosine kinase inhibitor genistein. We found that the ROS-production is 2 to 3 times higher in neutrophils on immunoglobulin G (IgG)-coated surfaces than in cells interacting with albumin- or fibrinogen-coated surfaces. Incubation with superoxide dismutase and catalase revealed that about 45% of the ROS was released extracellularly on IgG surfaces whereas corresponding values were 90% and 85% in neutrophils interacting with albumin and fibrinogen, respectively. The presence of platelets markedly increased the extracellular generation of ROS, mainly in neutrophils interacting with IgG- or fibrinogen-coated surfaces whereas the intracellular production was only modestly affected. Quantitative fluorescence microscopy of neutrophils stained with FITC-conjugated anti-phosphotyrosine antibodies showed a correlation between tyrosine phosphorylation, cell spreading, and ROS production. Platelets markedly amplified the anti-phosphotyrosine staining on both fibrinogen- and IgG-coated surfaces whereas the low level of tyrosine phosphorylation in neutrophils on albumin-coated surfaces was not further elevated by platelets. Furthermore, the tyrosine kinase inhibitor genistein inhibited both extra- and intracellular ROS production in neutrophils regardless of the presence of platelets. We demonstrate that plasma protein coating and the presence of platelets are crucial for the inflammatory response of adhering neutrophils and that the oxidative response correlates with the extent of tyrosine phosphorylation of proteins in focal contacts. 相似文献
76.
Gallstones--an increasing problem: a study of hospital admissions in England between 1989/1990 and 1999/2000 总被引:3,自引:0,他引:3
Kang JY Ellis C Majeed A Hoare J Tinto A Williamson RC Tibbs CJ Maxwell JD 《Alimentary pharmacology & therapeutics》2003,17(4):561-569
BACKGROUND: The number of operations for cholelithiasis increased from the 1950s to the 1990s. AIMS: To determine the time trends in cholelithiasis for hospital admissions, operations and in-hospital case fatalities in England between 1989/1990 and 1999/2000, and population mortality rates between 1979 and 1999. METHODS: Hospital Episode Statistics for admissions were obtained from the Department of Health and mortality data were obtained from the Office for National Statistics. RESULTS: Between 1989/1990 and 1999/2000, age-standardized hospital admission rates for cholelithiasis increased by 30% for males and 64% for females. The proportions of admissions undergoing an operation declined progressively over the study period. In 1999/2000, the frequency of operation was approximately 50-60% for most age groups, but decreased progressively with advancing age at > or = 65 years. The proportions of admissions undergoing therapeutic endoscopy increased several-fold, especially amongst older individuals. Case fatality rates declined. Mortality rates declined from 1979 to 1988, but showed no further change from 1989 to 1999. CONCLUSIONS: There has been a steady increase in admission rates for cholelithiasis over the study period. Whilst the frequency of operation has declined, the proportion of patients undergoing therapeutic endoscopy has increased. 相似文献
77.
Kang JY Hoare J Majeed A Williamson RC Maxwell JD 《The British journal of surgery》2003,90(12):1586-1592
BACKGROUND: The incidence of acute appendicitis declined in western countries between the 1930s and the early 1990s. The aim of this study was to determine time trends in hospital admissions for acute appendicitis in England between 1989-1990 and 1999-2000, and in population mortality rates for appendicitis from 1979 to 1999. METHODS:: Hospital Episode Statistics for admissions were obtained from the Department of Health and mortality data from the Office for National Statistics. RESULTS: Between 1989-1990 and 1999-2000, age-standardized hospital admission rates for acute appendicitis decreased by 12.5 per cent in male patients and by 18.8 per cent in female patients. The proportions of admissions that resulted in operation remained stable. Admission rates for non-specific mesenteric lymphadenitis fell. Admission rates for abdominal pain increased between 1989-1990 and 1995-1996, at which time the International Classification of Diseases codes changed. Between 1995-1996 and 1999-2000, admission rates for abdominal pain declined. Analysis of age-specific admission rates for acute appendicitis and abdominal pain from 1989-1990 to 1995-1996 showed that the decline in acute appendicitis could not be accounted for by a change in diagnostic practice. Mortality rates for acute appendicitis remained stable over the study period. CONCLUSION: Admission rates for acute appendicitis declined over the study period. This decline cannot be explained by reclassification. 相似文献
78.
Popliteal artery injuries: the Kashmir experience 总被引:7,自引:0,他引:7
BACKGROUND: Popliteal artery injuries pose a serious threat to limb survival. Blunt trauma appears to be associated with a higher amputation rate than penetrating trauma, probably because of the more extensive nature of the injuries. METHODS: Two hundred seventy-two cases of popliteal artery injury were studied retrospectively from 1989 to 2001, a warlike period in Kashmir. Preoperative angiography was not performed. Thirty-two percent of patients had associated venous injury and 24.6% of patients had associated bone fracture. RESULTS: Overall morbidity was 55%, with the most common complication being infection (24%). Secondary amputation had to be performed in 16 patients (5.5%). The amputation rate was not influenced by cause of injury and type of repair or the presence of venous injury, but associated bone fracture significantly increased the risk of amputation (p < 0.05). The patients who underwent repair more than 12 hours after sustaining injury had a significantly greater amputation rate (p < 0.05). CONCLUSION: Prompt resuscitation, vascularization, and proper technique appear to be the only correctable factors that improve limb salvage. 相似文献
79.
NM?JomhaEmail author PC?Anoop Janet?AW?Elliott K?Bagnall LE?McGann 《BMC musculoskeletal disorders》2003,4(1):5
Background
The identification of live cells using membrane integrity dyes has become a frequently used technique, especially with articular cartilage and chondrocytes in situ where tissue slices are used to assess cell recovery as a function of location. The development of a reproducible computerised method of cell evaluation would eliminate many variables associated with manual counting and significantly reduce the amount of time required to evaluate experimental results.Methods
To validate a custom computerised counting program, intra-person and inter-person cell counts of nine human evaluators (three groups – unskilled, novice, and experienced) were compared with repeated pixel counts of the custom program on 15 digitised images (in triplicate) of chondrocytes in situ stained with fluorescent dyes.Results
Results indicated increased reproducibility with increased experience within evaluators [Intraclass Correlation Coefficient (ICC) range = 0.67 (unskilled) to 0.99 (experienced)] and between evaluators [ICC = 0.47 (unskilled), 0.85 (novice), 0.93 (experienced)]. The computer program had perfect reproducibility (ICC = 1.0). There was a significant relationship between the average of the experienced evaluators results and the custom program results (ICC = 0.77).Conclusions
This study demonstrated that increased experience in cell counting resulted in increased reproducibility both within and between human evaluators but confirmed that the computer program was the most reproducible. There was a good correlation between the intact cell recovery determined by the computer program and the experienced human evaluators. The results of this study showed that the computer counting program was a reproducible tool to evaluate intact cell recovery after use of membrane integrity dyes on chondrocytes in situ. This and the significant decrease in the time used to count the cells by the computer program advocate its use in future studies because it has significant advantages.80.