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The pharmacology of a new pasteurized factor VIII (FVIII) concentrate derived from human blood plasma was studied in 23 adults with hemophilia A. In Part 1 of the study involving six nonbleeding subjects, the mean increase in FVIII activity was 1.43 +/- 0.34 U per ml 10 minutes after an intravenous dose of 50 U per kg. The intravascular survival kinetics in these six patients showed a biphasic decay curve with an initial mean half-life of 5.1 +/- 1.2 hours probably representing early redistribution, and a late half-life of 13.3 +/- 4.9 hours. In Part 2 of the study, the activity at 10 minutes was measured in another 17 patients, as well as in one patient already studied in Part 1. The mean increase in activity with the 24 observations was 1.13 +/- 0.37 U per ml with a mean FVIII dosage of 51.0 +/- 2.6 U per kg of body weight. Only one patient had an allergic reaction, which did not recur when the patient was given a second lot. 相似文献
34.
I Sayers J Hawley CE Stewart CK Billington A Henry JR Leighton-Davies SJ Charlton IP Hall 《British journal of pharmacology》2009,158(1):277-286
Background and purpose:
Indacaterol is a novel β2-adrenoceptor agonist in development for the treatment of chronic obstructive pulmonary disease. The aim of this study was to investigate the comparative pharmacology of indacaterol in recombinant cells expressing the common polymorphic variants of the human β2-adrenoceptor and in human primary airway smooth muscle (ASM) cells.Experimental approach:
Chinese hamster ovarian-K1 cell lines expressing high and low levels of the common human β2-adrenoceptor variants were generated [Gly16-Glu27-Val34-Thr164(GEVT), RQVT, GQVT] and also the rare GQVI variant. Human primary ASM cells were isolated from explants of trachealis muscle. Adenosine-3′,5′-cyclic-monophosphate production was used as an outcome measure.Key results:
In both the low- and high-expression recombinant GEVT ‘wild type’ cell lines indacaterol is a high-efficacy agonist. Salmeterol and formoterol were identified as low- and high-efficacy agonists, respectively, and showed similar potencies to indacaterol irrespective of the β2-adrenoceptor genotype. The I164 variant cell line was associated with a reduced capacity to generate adenosine-3′,5′-cyclic-monophosphate in response to β2-adrenoceptor agonist. In the human primary ASM cells indacaterol gave a maximal response intermediate between that of salmeterol and formoterol.Conclusions and implications:
These data demonstrate that indacaterol is a high-efficacy agonist in recombinant cell systems but acts with lower efficacy in human primary ASM cells. No marked genotype-dependent effects were observed for common variants; however, changes in I164 receptor activity were identified, which were dependent on the level of expression of β2-adrenoceptors. 相似文献35.
Denise?W?Pallett Emily?Soh Mary-Lou?Edwards Kathleen?Bodey Laurie?CK?Lau J?Ian?Cooper Peter?H?Howarth Andrew?F?Walls Hui?Wang 《Environmental health : a global access science source》2009,8(Z1):S10
Background
Wild plants harbour a variety of viruses and these have the potential to alter the composition of pollen. The potential consequences of virus infection of grasses on pollen-induced allergic disease are not known.Methods
We have collected pollen from Dactylis glomerata (cocksfoot; a grass species implicated as a trigger of allergic rhino-conjunctivitis) from Wytham Wood, Oxfordshire UK. Extracts were prepared from pollen from uninfected grass, and from grass naturally infected by the Cocksfoot streak potyvirus (CSV). Preparations of pollen from virus-infected and non-infected grasses were employed in skin testing 15 grass pollen-allergic subjects with hayfever. Allergen profiles of extracts were investigated by Western blotting for IgE with sera from allergic subjects.Results
The prevalence of CSV infection in cocksfoot grasses sampled from the study site varied significantly over an eight-year period, but infection rates of up to 70% were detected. Virus infection was associated with small alterations in the quantities of pollen proteins detected by polyacrylamide gel electrophoresis, and in the patterns of allergens identified by Western blotting with IgE from grass pollen allergic subjects. For individual subjects there were differences in potencies of standardised extracts of pollen from virus-free and virus-infected plants as assessed by skin testing, though a consistent pattern was not established for the group of 15 subjects.Conclusion
Infection rates for CSV in cocksfoot grass can be high, though variable. Virus-induced alterations in components of grass pollen have the potential to alter the allergenic potency.36.
Isospora belli is an opportunistic protozoan causing wasting diarrhea especially in patients with an immunocompromised status. Diagnosis is usually established by demonstrating the oocyst of the organism on stool examination, which however can often be inconclusive. Serological tests for isosporiasis are currently not available. In such a scenario, biopsy often provides evidence for a confirmatory diagnosis. We describe two such cases, in which intestinal biopsy was the only diagnostic evidence of isosporiasis as the cause for chronic diarrhea. 相似文献
37.
全破壁灵芝孢子治疗男性更年期综合征 总被引:3,自引:0,他引:3
目的 :探讨全破壁灵芝孢子治疗法对男性更年期综合征的疗效。方法 :通过对 138例诊断为男性更年期综合征病人分组 ,其中 80例作全破壁灵芝孢子胶囊治疗并对其临床症状 ,血睾酮、SOD、MDA水平及主观抑郁症状评分作观察 ,并与 5 8例病情相同的病人予安慰剂对照。结果 :治疗组的病人症状改善率为 74 .3% ,血睾酮水平 3周前后分别为 (131.5 1± 19.12 )mg/L与 (2 5 3.78± 2 1.4 5 )mg/L ,SOD水平 3周前后分别为 (10 6 8.3± 12 1.4 )U/ g·Hb与 (1178.1± 132 .6 )U/ g .Hb ,MDA水平 3周前后分别为 (7.6± 0 .8) μmol/L与 (5 .8± 0 .6 )μmol/L。抑郁症状评分各指标均有较大改善。 结论 :全破壁灵芝孢子胶囊是治疗男性更年期综合征的一种有效、安全的方法。 相似文献
38.
Respiratory patterning of the rat olfactory bulb unit activity: nasal versus tracheal breathing 总被引:3,自引:0,他引:3
To assess the role of nasal/tracheal (N/T) breathing in the respiratory patterning of the olfactory bulb (OB) neurons, the activity of 21 units was recorded in 6 anesthetized rats set with a cannula enabling reversible tracheotomy: the rats could inhalate either through nasal pathways or through trachea directly. Shift from tracheal to nasal breathing induced respiratory patterning in 7 units. The changes were steady, reversible and reproducible. The present data, matched with previous ones, indicate that tracheotomy and anesthesia decrease the occurrence of respiratory patterning in OB neurons. The experiments also suggest that peripheral as well as central structures may be a source of respiratory modulation in the olfactory bulb. 相似文献
39.
目的:总结速度滑冰与短道速度滑冰运动员各项生理生化指标,开发应用生理生化指标对身体功能进行评定,为科学训练提供参考依据。方法:分析速度滑冰与短道速度滑冰项目特点,并根据其特点制定了各项生理生化指标的参考值。结果:速度滑冰与短道速度滑冰均有周期性耐力性项目特点,要求运动员必须具备较强的无氧代谢能力,尤其是抗乳酸能力,可用4mmol/L做无氧阈训练监控指标。血尿素参考值4 ̄7mmol/L,功能下降或训练量大时增高。血清肌酸激酶强度训练时可高达16.67μkat/L以上。血红蛋白参考值为男120 ̄160g/L,女110 ̄150g/L。免疫指标和内分泌指标均应定期监测,为提供身体功能信息有重要意义。结论:可用血乳酸系统监控和评估有氧与无氧耐力水平,运动员身体功能评定是科学化训练重要保证,是科学训练的重要部分。 相似文献
40.
Abstract The objective of this study was to evaluate the utility of a polymerase chain reaction (PCR) assay in detecting Mycobacterium tuberculosis in bronchoalveolar lavage (BAL) specimens of patients suspected of having active pulmonary tuberculosis (TB) but who were sputum smear-negative. Patients undergoing investigation for suspected pulmonary TB at the University Hospital, Kuala Lumpur, and who were sputum smear-negative underwent fibreoptic bronchoscopy and BAL. One portion of each lavage specimen was submitted for smear examination for acid-fast bacilli and mycobacterial culture and the other portion assayed by PCR for the presence of a 562-base pair DNA segment belonging to the insertion sequence IS986, unique to the M. tuberculosis complex. As controls, lavage specimens from patients with other lung lesions were also similarly tested. The PCR assay gave a positivity rate of 80.9% (55 of 68) compared with 8.8% of smear examination and 7.4% of culture for detecting M. tuberculosis in BAL specimens. The assay was positive in two of 45 BAL specimens from 35 control subjects. The PCR assay was more sensitive than smear and culture in detecting M. tuberculosis in BAL specimens of patients with sputum smear-negative pulmonary TB. 相似文献