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排序方式: 共有471条查询结果,搜索用时 15 毫秒
461.
Recombinant granulocyte colony stimulating factor (G-CSF) was administered daily for 14 days to healthy young (Y) (20 to 30 years) and elderly (O) (70 to 80 years) volunteers to evaluate the effects of age on the neutrophil (polymorphonuclear leukocytes, PMN) responses. Thirty-eight volunteers were randomized to receive 0 micrograms, 30 micrograms, or 300 micrograms per day. Baseline neutrophil counts (ANC), peak ANCs, and the rate of attaining the peak ANC were similar in both age groups at both doses. The peak ANC was increased 5-fold at 30 micrograms and 15-fold at 300 micrograms in both the young and elderly. Daily tests of PMN function, as measured by an automated chemiluminescence system, showed nearly identical responses to several agonists for both age groups. Marrow proliferative activity as reflected by the percentage of cells in the marrow neutrophil mitotic pool also increased similarly for both age groups at both doses. In contrast, there was an age-related change in blood colony formation as measured by the blood CFU-GM assay. Compared with controls at the 30 micrograms dose, mean colony formation was increased 2-fold in the young versus no change in the elderly and at the 300 micrograms dose 24- fold in the young versus 12-fold in the elderly. These studies indicate that neutrophil responses to rhG-CSF are equivalent in healthy young and elderly volunteers but the mobilization of progenitor cells, as measured by the CFU-GM assay appears to differ substantially. 相似文献
462.
Anne Sophie Lafitte GS Marie Blouet MD Frédérique Belloy MD Alin Borha MD Guillaume Benoist MD PhD 《Journal of clinical ultrasound : JCU》2018,46(4):282-285
Diagnosis of fetal spinal dysraphism is a challenge. It is difficult to distinguish between a meningocele, myelomeningocele, and a recently described entity called limited dorsal myeloschisis (LDM). Although myelomeningocele is associated with a poor prognosis, LDM can have a good outcome. We present a case of prenatally diagnosed LDM. Because sonographic examination revealed a round, cystic, septated cervical mass without associated cerebral anomalies, the lesion was initially considered an isolated meningocele. Fetal MRI contributed to correct the diagnosis. A diagnostic error can lead to the wrong surgical support or even the termination of pregnancy. Therefore, we highlight the importance of fetal MRI in such cases, particularly when no cerebral abnormalities are observed on sonographic examination. 相似文献
463.
Achyut Sarkar Imran Ahmed Arindam Pande GS Naveen Chandra 《Journal of Cardiovascular Echography》2014,24(2):60-63
Left ventricular non-compaction or “spongy myocardium”, is a rare congenital cardiomyopathy that should be considered as a possible diagnosis because of its potential complications. Echocardiography is the diagnostic tool of choice, and cardiomagnetic resonance (CMR) can confirm or rule out this disease. Herein, we report the case of an 8-month-old female child who presented with congestive cardiac failure (CCF) and symptomatic complete heart block (CHB). An echocardiogram established the diagnosis as non-compaction cardiomyopathy (NCCM). An associated double outlet right ventricle with ventricular septal defect and valvular pulmonary stenosis was found. Cardiac magnetic resonance study confirmed the findings. This singular case report of NCCM highlights the importance of clinical awareness of this rare abnormality, its varied presentation and associated cardiac anomalies. The article revisits NCCM and focuses on the practical issues for a proper echodiagnosis. 相似文献
464.
465.
Tin-protoporphyrin suppression of hyperbilirubinemia in mutant mice with severe hemolytic anemia 总被引:10,自引:0,他引:10
Tin-protoporphyrin is a potent competitive inhibitor of heme oxygenase both in vivo in animals and in vitro in isolated enzyme preparations, and when administered to neonatal rats, prevents the development of postnatal hyperbilirubinemia. In this study we examined the effect of the metalloporphyrin on the activity of heme oxygenase in liver, kidney, and spleen, and on the level of bilirubin in plasma in three types of anemic mutant mice with severe hemolytic diseases. We report that the administration of tin-protoporphyrin to anemic mutants homozygous for severe hemolytic disease results in substantial inhibition of heme oxidation in liver, spleen, and kidney and in significant reduction of plasma bilirubin levels. Tin-protoporphyrin thus has the capacity to significantly inhibit in vivo heme degradation and to concurrently diminish plasma bilirubin levels in severe chronic hemolytic disorders. 相似文献
466.
467.
Lectin and epidermal growth factor domains of P-selectin at physiologic density are the recognition unit for leukocyte binding 总被引:5,自引:0,他引:5
P-selectin is an integral membrane glycoprotein on stimulated platelets and endothelial cells that serves as a receptor for leukocytes. To estimate the density of P-selectin in membranes necessary to support adhesion, we incorporated purified P-selectin at varying concentrations into phospholipid bilayers that encapsulated glass microspheres. Maximal binding of these lipospheres to HL60 cells, a P-selectin ligand- expressing cell line, was approached at a P-selectin density of about 100 molecules per microns 2; half-maximal binding was observed at about 50 to 60 molecules per microns 2. Compatible results were obtained with P-selectin expressed on Chinese hamster ovary cells. The P-selectin density on stimulated platelets was estimated to be 150 to 200 molecules/microns 2. To identify the domains of P-selectin required for HL60 cell binding, chimeras of P-selectin and L-selectin were stably expressed in Chinese hamster ovary cells and clones that expressed the chimeras at the estimated physiologic density were selected. Chimeras containing the P-selectin lectin and epidermal growth factor (EGF) domains or the lectin, EGF, and short consensus repeats bound HL60 cells equivalently, but a chimera containing the P-selectin lectin domain alone bound HL60 cells much less well. These results indicate that at a physiologically relevant P-selectin density on membrane surfaces, the lectin, and EGF domains of P-selectin are together required for optimal leukocyte binding. 相似文献
468.
Neelima Mishra Jai Prakash Narayan Singh Bina Srivastava Usha Arora Naman K Shah SK Ghosh RM Bhatt SK Sharma MK Das Ashwani Kumar Anupkumar R Anvikar Kamlesh Kaitholia Ruchi Gupta GS Sonal AC Dhariwal Neena Valecha 《Bulletin of the World Health Organization》2012,90(12):895-904
Objective
To describe India’s National Antimalarial Drug Resistance Monitoring System, measure the efficacy of first-line malaria treatments, and determine risk factors for treatment failure.Methods
In 2009–2010, prospective studies with 28 days of follow-up were conducted at 25 sentinel sites. Patients infected with Plasmodium falciparum were given artesunate plus sulfadoxine-pyrimethamine (AS+SP); those infected with P. vivax were given chloroquine. Polymerase chain reaction was used to distinguish post-treatment reinfection from treatment failure. Isolates of P. falciparum were checked for dhfr and dhps mutations.Findings
Overall, 1664 patients were enrolled. Kaplan–Meier survival analysis showed an efficacy of 98.8% for AS+SP. Most patients with P. falciparum parasitaemia cleared their parasitaemias within 24 hours of treatment initiation, but six, including four with treatment failure, remained parasitaemic after 72 hours. Double mutants in dhfr were found in 68.4% of the genotyped isolates. Triple or quadruple mutants in dhfr and mutations in dhps were rare. A daily dose of artesunate of < 3 mg per kg of body weight, age of less than 5 years, and fever at enrolment were associated with an increased risk of treatment failure. Chloroquine remained 100% efficacious and generally cleared P. vivax parasitaemias within 48 hours. Vomiting (seen in 47 patients) was the most common adverse event.Conclusion
India’s National Antimalarial Drug Resistance Monitoring System provides wide coverage. The first-line antimalarials used in the country remain safe and efficacious. The treatment of malaria in young children and the relative benefits of age- and weight-based dosing need further exploration. 相似文献469.
目的:分析过量表达的外源性糖皮质激素受体在调控肺泡巨噬细胞表达炎性细胞因子中的作用。方法:实验于2005-10/2006-03在解放军南京军区南京总医院呼吸病实验室完成。①选用成年健康Wistar大鼠10只,雌雄不拘。采用大鼠糖皮质激素受体真核表达质粒pCMV-rGR转染体外培养肺泡巨噬细胞,将肺泡巨噬细胞分为转染组与非转染组,其中转染组细胞在质粒转染24h后用于实验,各组对以下时相点进行观察:正常对照(加等量生理盐水)、脂多糖 地塞米松作用4,8和12h,脂多糖与地塞米松作用浓度分别为100μg/L,1×10-5mol/L,于不同时相点收集细胞。②转染24h后WesternBlotting检测细胞总蛋白和核蛋白中糖皮质激素受体蛋白表达变化。同时收集细胞培养上清,采用酶联免疫吸附法浊定细胞培养上清中肿瘤坏死因子α、白细胞介素1β水平。③多组间比较用方差分析,两两比较用SNK检验。结果:①质粒转染肺泡巨噬细胞后糖皮质激素受体表达变化:转染组细胞总蛋白中糖皮质激素受体表达明显高于非转染组(3.75±0.25,1.21±0.16,P<0.01),转染组细胞核蛋白中糖皮质激素受体表达量与非转染组相近(1.15±0.12,1.09±0.11,P>0.05)。②脂多糖和地塞米松作用后核蛋白中糖皮质激素受体表达变化:脂多糖和地塞米松作用后4,8,12h转染组细胞核蛋白中糖皮质激素受体表达量分别为4.02±0.09,2.13±0.08,1.22±0.15,非转染组细胞核蛋白中糖皮质激素受体表达量分别为4.08±0.13,2.09±0.11,1.19±0.17,两组细胞核蛋白中糖皮质激素受体表达变化趋势一致,均于4h达到峰值,8h显著降低,12h达到最低,两组同时相点比较,差异不明显(P>0.05)。③脂多糖和地塞米松作用后细胞培养上清中细胞因子表达变化:转染组脂多糖和地塞米松作用后4,8,12h肿瘤坏死因子α表达分别为(32.16±3.99),(56.82±8.43),(73.34±9.97)ng/L,非转染细胞分别为(34.28±4.25),(59.82±9.65),(71.41±8.35)ng/L;转染组脂多糖和地塞米松作用后4,8,12h细胞上清中白细胞介素1β质量浓度分别为(67.57±18.37),(83.17±8.55),(97.55±8.27)ng/L,非转染分别为(62.23±15.64),(85.72±9.37),(99.07±9.25)ng/L。两组细胞上清中肿瘤坏死因子α、白细胞介素1β表达随时间逐渐增加,均于12h均达到峰值,同时相点两组比较均无明显差异(P>0.05)。结论:①通过体外糖皮质激素受体基因转染可以有效地在肺泡巨噬细胞中过量表达外源性糖皮质激素受体,并且定位于胞质内。②地塞米松作用后,肺泡巨噬细胞核内糖皮质激素受体表达明显增加,但随后又出现表达下调现象。③体外基因转染后胞质中过量表达的外源性糖皮质激素受体不能发生核移位,所检测的均为内源性糖皮质激素受体。④通过基因转染而过量表达的外源性糖皮质激素受体,不能发挥正常的抑炎生物学活性。 相似文献
470.
Angiotensin-converting-enzyme inhibitors in the management of cardiac failure: are we ignoring the evidence? 总被引:2,自引:0,他引:2
Hillis GS; Trent RJ; Winton P; MacLeod AM; Jennings KP 《QJM : monthly journal of the Association of Physicians》1996,89(2):145-150
The benefits of angiotensin-converting enzyme (ACE) inhibition in the
management of cardiac failure have been extensively documented. However,
little is known about its impact upon the investigation and management of
this condition. We assessed how patients diagnosed as having cardiac
failure were investigated, which patients were treated with ACE inhibitors
and with what dosages. We reviewed the case notes of all 343 patients
discharged from Aberdeen Royal Infirmary 1 July-31 December 1992 with a
diagnosis of cardiac failure. In addition, a questionnaire was sent to the
general practitioners of the 166 patients still alive in October 1994. Only
40% of patients were discharged from hospital on ACE inhibitors. In 58.8%,
the diagnosis of cardiac failure was based purely on clinical or
radiological grounds. At discharge, 76.1% of patients were on lower doses
of ACE inhibitors than those used in the major survival studies; with 68.9%
receiving similar doses two years later. The majority of patients with
heart failure are under- investigated and under-treated.
相似文献