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排序方式: 共有1013条查询结果,搜索用时 15 毫秒
91.
Segal I; Sharer NM; Kay PM; Gutteridge JM; Braganza JM 《QJM : monthly journal of the Association of Physicians》1996,89(1):45-53
Vitamin C can be used to overcome oxidative stress and ease pain in chronic
pancreatitis. But its use is deprecated in conditions of tissue iron
overload, because its bioactive form, ascorbate, can accelerate
free-radical reactions that are driven by transition metals. We measured
iron, ascorbate and copper in Sowetan Blacks (RSA) with chronic
pancreatitis, obtaining serum/plasma from 14 consecutive patients and 15
controls. Compared with data from corresponding groups in Manchester,
African samples had less ascorbate (p < 0.0001), but more caeruloplasmin
(p < 0.0001). African and British controls had comparable iron and
iron-binding capacity. Plasma from African patients had less ascorbate than
that from African controls (p < 0.005) and in six samples, ferritin
exceeded 300 micrograms/l (677 pmol/l). Low- molecular-mass iron or copper,
capable of participating in free radical reactions, was not detected.
British patients, had similar caeruloplasmin levels to African patients but
higher ascorbate levels. There is no evidence of iron overload in our
African samples. Outwardly healthy controls from Soweto have elevated
levels of caeruloplasmin, possibly to compensate for dietary deficiency of
ascorbate. Persistent oxidative stress is a unifying feature of chronic
pancreatitis, but its degree is higher in African than British patients.
Supplements of vitamin C should be safe in Blacks of southern Africa.
相似文献
92.
D C Rijken E Hoegee-de Nobel A F H Jie D E Atsma M J Schalij W Nieuwenhuizen 《Journal of thrombosis and haemostasis》2008,6(1):151-157
BACKGROUND: The development of global tests for the fibrinolytic capacity in blood is hampered by the low base-line fibrinolytic activity in blood, by the involvement of both plasmatic components and blood cells in the fibrinolytic system and by the loss of fibrinolytic activity as a result of the action of plasminogen activator inhibitor-1 (PAI-1). OBJECTIVE: To develop a new test for the global fibrinolytic capacity (GFC) of whole blood samples. METHODS AND RESULTS: Collection of blood in thrombin increased the subsequent generation of fibrin degradation products. This was ascribed to rapid clot formation and concomitant reduction of in vitro neutralization of tissue-type plasminogen activator (tPA) by PAI-1. On the basis of this observation, the following test was designed: blood samples were collected in thrombin with and without aprotinin and clots were incubated for 3 h at 37 degrees C. The GFC was assessed from the difference between the fibrin degradation products in the two sera. The assay was applied to blood samples from patients and healthy subjects. Other hemostasis parameters were determined in plasma samples taken simultaneously. The GFC varied considerably (normal range 0.13-13.6 microg mL(-1)); physical exercise strongly increased the GFC. Statistically significant correlations were found with tPA activity, PAI-1 activity and fibrinogen level. A mixture of antibodies against tPA and urokinase-type plasminogen activator (uPA) completely inhibited the GFC. An inhibitor of activated thrombin-activatable fibrinolysis inhibitor (TAFI) accelerated fibrinolysis 8-fold. CONCLUSION: The new test represents a global assessment of the main fibrinolytic factors in plasma and potentially those associated with blood cells. 相似文献
93.
The postoperative fibrinolytic shutdown: a rapidly reverting acute phase pattern for the fast-acting inhibitor of tissue-type plasminogen activator after trauma 总被引:11,自引:0,他引:11
C Kluft J H Verheijen A F Jie D C Rijken F E Preston H M Sue-Ling J Jespersen A O Aasen 《Scandinavian journal of clinical and laboratory investigation》1985,45(7):605-610
The plasma activity level of the recently discovered fast-acting inhibitor of tissue-type plasminogen activator (t-PA) was found to be temporarily increased after surgery, myocardial infarction and severe trauma. Detailed analysis of the postoperative period revealed simultaneously increased t-PA antigen and inhibition and decreased t-PA activity only on the first postoperative day. These changes were more rapid than those in fibrinogen and C-reactive protein. It is concluded that t-PA inhibition shows the most rapidly changing pattern observed so far in response to trauma. The postoperative fibrinolytic shutdown in blood fibrinolytic activity can be ascribed to a primary increase in t-PA inhibitor levels. 相似文献
94.
自体造血干细胞的体外净化 总被引:1,自引:0,他引:1
目的:综合分析自体造血干细胞体外净化的方法。资料来源:应用计算机检索Medline 1991-01/2003-12有关自体造血干细胞体外净化方法的文章,检索词“purging,HSCT”,并限定文章语言种类为English。同时计算机检索CNKI数据库1991-01/2003-12有关自体造血干细胞体外净化方法的文章,检索词“体外净化,PUVA”,并限定文章语言种类为中文。资料选择:对相关资料进行整理,选取同一领域、不同方面的文献,以近期发表或权威杂志的文章优先。资料提炼:共检索到42篇有关自体造血干细胞体外净化方法的文献,其中24篇文章符合要求。排除18篇,其中15篇系重复同一研究,3篇为Meta分析。资料综合:自体造血干细胞的体外净化方法很多,如物理方法、生物学方法、药物方法、免疫净化、基因净化等。每种净化方法都有其各自的优势和不足,如淋巴系统疾病可以采用免疫净化;慢性粒细胞白血病患者可考虑反义技术;大多数患者则均可以考虑药物净化的方法。结论:针对不同的疾病,可以选择不同的净化方法,还可以将几种净化方法联合起来,其效果和方法的改进也在不断的研究探索中。 相似文献
95.
Reduction in transmission of hepatitis C after the introduction of a heat-treatment step in the production of C1-inhibitor concentrate 总被引:1,自引:0,他引:1
BACKGROUND: The transmission of viral infections via protein concentrates made from a large pool of plasma depends on the selection of donors, fractionation process, and virucidal methods. To date, no data are available on the infectivity risk of plasma concentrates of the inhibitor of the first component of complement (C1-INH). STUDY DESIGN AND METHODS: The prevalence of blood-borne viral infections and levels of transaminases were evaluated in patients treated with a large- pool plasma concentrate of the inhibitor of C1-INH before and after the introduction of virucidal methods. The study included 85 patients with hereditary angioedema and 4 with acquired angioedema. The patients were divided into three groups: 1) 48 untreated patients; 2) 22 patients treated with non-virus-inactivated C1-INH concentrates; and 3) 19 patients treated with virus-inactivated concentrates. Serum samples obtained at various times after the infusion of concentrate were assayed for alanine amino-transferase and tested for hepatitis B surface antigen and antibodies to hepatitis C virus (anti-HCV) and human immunodeficiency virus (anti-HIV); anti-HCV-negative subjects exposed to the concentrate were also tested for HCV RNA. RESULTS: Prevalences of HCV infection and elevated alanine aminotransferase are significantly lower in patients treated with virus-inactivated concentrates than in those exposed to non-virus-inactivated concentrates. No patients were anti-HIV positive. CONCLUSION: This study suggests that C1-INH concentrates transmitted HCV, but that the virucidal methods adopted are effective in reducing the infectivity. 相似文献
96.
A Lorentz ; A Jendrissek ; KU Eckardt ; M Schipplick ; PM Osswald ; A Kurtz 《Transfusion》1991,31(7):650-654
The variations in plasma erythropoietin (EPO) concentration during preoperative deposit of autologous blood were studied in 12 patients (8 men, 4 women). Four donations were scheduled at weekly intervals. A predonation hemoglobin concentration of 11 g per dL (110 g/L) was required. Hemoglobin concentration decreased from 14.3 +/- 1.1 g per dL (143 +/- 11 g/L) (mean +/- SD) before the first donation to 11.7 +/- 0.7 g per dL (117 +/- 7 g/L) on Day 22 (p less than or equal to 0.0001). Reticulocyte counts increased from a median of 31,800 (range, 4900-95,000) per microL (median, 32 x 10(9)/L [range, 5-95 x 10(9)/L]) to 93,800 (16,800-194,900) per microL (median, 94 x 10(9)/L [range, 17-195 x 10(9)/L]) on Day 28 (p less than or equal to 0.01). Plasma EPO concentration was 17.8 +/- 5.1 mU per mL prior to the first donation and displayed a small and transient peak after each donation. A sustained elevation followed each peak. Although plasma EPO concentration differed significantly from the baseline value after the first donation, only the peak concentrations after the second (35.5 +/- 15.5 mU/mL), third (38.0 +/- 14.5 mU/mL), and fourth (36.1 +/- 11.0 mU/mL) donations exceeded the normal range. The moderate, biphasic increase in plasma EPO concentration and the moderate increase in erythropoiesis suggest two strategies in autologous blood donation that should be investigated with respect to efficiency and safety: 1) more aggressive donation schemes, which reduce donation intervals and/or the minimum hemoglobin concentration and 2) the administration of recombinant human EPO. 相似文献
97.
Transmission of hepatitis G virus in patients with angioedema treated with steam-heated plasma concentrates of C1 inhibitor 总被引:2,自引:0,他引:2
F De Filippi; R Castelli ; M Cicardi ; R Soffredini ; MG Rumi ; E Silini ; PM Mannucci ; M Colombo 《Transfusion》1998,38(3):307-311
BACKGROUND: Hepatitis G virus (HGV) is a blood-borne flavivirus that may cause acute and chronic transfusion-transmitted infections. Patients with complement component 1 (C1) inhibitor (C1-INH) deficiency may acquire blood-borne infections through infusion of plasma concentrates. STUDY DESIGN AND METHODS: Serum samples from 84 patients with C1-INH deficiency (19 who received unmodified C1-INH concentrates, 23 who received steam-heated concentrates, and 42 untreated patients) were tested for HGV RNA and hepatitis C virus (HCV) RNA by a nested polymerase chain reaction (PCR). The samples were also tested for antibodies to the E2 envelope protein of HGV (anti-HGV) and to HCV with enzyme-linked immunosorbent assays. RESULTS: Nine (11%) patients had serum HGV RNA; that is, 7 (17%) of 42 patients previously treated with C1-INH concentrates and 2 of 42 previously untreated patients. HGV RNA was as common in the 19 patients treated with unmodified concentrates as in the 23 given steam-heated concentrates (16 vs. 17%, p = 0.60). Anti-HGV was more common among the recipients of unmodified concentrates than among those given steam-heated concentrates (26 vs. 0%, p = 0.014). HCV RNA was more frequently detected in treated patients than in untreated patients (33 vs. 7%, p = 0.005) and in the 19 recipients of unmodified concentrates than in the 23 treated with steam-heated concentrates (58 vs. 16%, p = 0.003). Only one HGV RNA- seropositive patient had elevated serum aminotransferase activity, compared to 11 with HCV RNA. CONCLUSION: HGV was transmitted by both unmodified and steam-heated concentrates, but it caused persistent viremia in a minority of the cases and was rarely associated with liver disease. 相似文献
98.
BACKGROUND: Individuals with epilepsy or seizure disorders are restricted from donating blood because of concern that they are prone to adverse donor reactions such as syncope and convulsions. A study evaluating whether that concern is warranted is reported. STUDY DESIGN AND METHODS: During a 2-year period beginning in 1987, blood donors in Maryland with a history of seizures were actively recruited by the American Red Cross. Adverse donor reactions were classified as "slight", indicating dizziness and nausea without loss of consciousness; "moderate," denoting syncope; and "severe," indicating convulsive syncope. RESULTS: There were 329,143 satisfactory blood donations; 613 individuals reporting a history of seizures donated blood a total of 723 times. Among donors with seizures, 186 (35.7%) were taking antiepileptic medication, and 61 (8.4%) had had one or more seizures in the preceding year. Individuals with seizures had a low incidence of adverse reactions (3.34%). Although this incidence was slightly higher than that in the entire population (2.24%), the difference was not significant. In particular, the risk of syncope with or without convulsive activity was low for people with seizures (0.21%) and not significantly greater than that in other donors (0.28%). CONCLUSION: Individuals with seizures or epilepsy are not at greater risk for adverse reactions after blood donation, and major restrictions on their participation as blood donors are not warranted. 相似文献
99.
Roorda LD Roebroeck ME van Tilburg T Molenaar IW Lankhorst GJ Bouter LM Boonstra AM de Laat FA Caron JJ Burger BJ Heyligers IC Nollet F Stover-Van Herk IE Perez RS Meijer JW Rijken PM;Measuring Mobility Study Group 《Archives of physical medicine and rehabilitation》2005,86(12):1396-2283
OBJECTIVE: To develop a hierarchical scale that measures activity limitations in walking in patients with lower-extremity disorders who live at home. DESIGN: Cross-sectional study. SETTING: Orthopedic workshops and outpatient clinics of secondary and tertiary care centers. PARTICIPANTS: Patients (N=981; mean age +/- standard deviation, 58.6+/-15.4 y; 46% men) living at home, with different lower-extremity disorders: stroke, poliomyelitis, osteoarthritis, amputation, complex regional pain syndrome type I, and diabetic and degenerative foot disorders. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: (1) Fit of the monotone homogeneity model, indicating whether items can be used for measuring patients; (2) fit of the double monotonicity model, indicating invariant (hierarchical) item ordering; (3) intratest reliability, indicating repeatability of the sum score; (4) robustness, addressing the clinimetric properties within subgroups of patients; and (5) differential item functioning, addressing the validity of comparisons between subgroups of patients. RESULTS: Thirty-five of 41 dichotomous items had (1) good fit of the monotone homogeneity model (coefficient H=.50), (2) good fit of the double monotonicity model (coefficient H(T)=.33), (3) good intratest reliability (coefficient rho=.95), (4) satisfactory robustness (within subgroups of patients defined by age, sex, and diagnosis), and (5) some differential item functioning (6 items in amputees compared with nonamputees). CONCLUSIONS: A hierarchical scale, with excellent scaling characteristics, was developed to measure activity limitations in walking in patients with lower-extremity disorders who live at home. The measurements should be interpreted cautiously when making comparisons between amputees and nonamputees. 相似文献
100.