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21.
A new principle applied to the determination of calcium in biological materials by flame photometry
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The effect of magnesium sulphate in releasing calcium emission from interference by phosphate and sulphate has been investigated. 相似文献
22.
Theodossiou C Schwarzenberger P Espinozadelgado I Wynn R Schapira D 《Oncology reports》1997,4(6):1305-1310
Breast cancer is the most common malignancy seen in women. Due to the increasing awareness for this disease and the increasing use of screening mammography, more patients are now diagnosed with early stage disease. Over the past few years, the indications for adjuvant treatment have expanded considerably, and more women are now candidates for chemotherapy, hormonal therapy, or both. The role of various prognostic factors and their implications on the design of a multidisciplinary therapeutic approach is discussed in this review. Current recommendations regarding the extent of the surgery, the role of radiation, and its integration to the adjuvant treatment are discussed. Guidelines on adjuvant chemotherapy and adjuvant hormonal therapy are also being presented. 相似文献
23.
M Clerici A Sarin R L Coffman T A Wynn S P Blatt C W Hendrix S F Wolf G M Shearer P A Henkart 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(25):11811-11815
In vitro T-cell receptor-induced programmed cell death in both activated T cells from human immunodeficiency virus-seronegative (HIV-) donors and resting T cells from HIV+ donors was substantially influenced by cytokines. Addition of exogenous recombinant "type 1" lymphokines interferon gamma and interleukin 2 (IL-2), as well as the macrophage-produced IL-12, which favor cell-mediated T-cell responses, blocks both systems of T-lymphocyte programmed cell death. In contrast, the "type 2" lymphokines IL-4 and IL-10, which favor antibody responses, either had no effect or enhanced these systems of in vitro T-cell programmed cell death. A role for endogenously produced cytokines was suggested by the inhibition of T-cell receptor-mediated death by antibodies against IL-4 and IL-10 and its enhancement by anti-IL-12 in cultures containing monocytes. These results demonstrate that the functional properties of type 1 and type 2 cytokine classes may be further extended to include their effects on T-cell programmed cell death and their possible role in the pathogenesis of HIV infection. 相似文献
24.
Wynn J 《Air medical journal》1994,13(10):436, 438
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目的: 研究1,25-二羟维生素D3 对结肠癌细胞系Caco-2 细胞中报告基因表达的作用,并探讨在报告载体pGL2 序列中存在潜在的抑制性维生素D应答元件(VDRE)的可能性。方法: 采用磷酸钙沉淀法将报告载体转染入Caco-2 细胞。Caco-2细胞经不同浓度1,25-二羟维生素D3 处理后测定细胞裂解液中表达的荧光素酶活性。结果: 应用pGL2 报告载体时,当用pSG5-VDR表达载体共转染后,1,25-二羟维生素D3显著地抑制Caco-2 细胞荧光素酶的表达(P< 0.05);而未使用该表达载体共转染则无抑制作用(P> 0.05)。应用pGL3 报告载体时,不同浓度的1,25-二羟维生素D3 对pLG3转染后Caco-2 细胞表达的荧光素酶活性均无显著抑制作用(P> 0.05),该作用不依赖是否存在有pSG5-VDR表达载体共转染。结论:1,25-二羟维生素D3 对报告载体PGL2 荧光素酶表达具有抑制作用,而对pGL3 则否;类似人类PTH基因中的潜在抑制性VDRE存在于报告载体pGL2,在pGL3 中该VDRE业已改变。 相似文献
27.
A causal connection between maternal nutrient intake and birth outcome is not universally accepted. In this paper further empirical support is provided, particularly in relation to the impact of maternal nutrition around the time of conception or very early in pregnancy. It is argued that the hypothesis that maternal nutrition has no connection with birthweight is very easily refuted. It is suggested that there should be a new category of recommended dietary allowances; "women in anticipation of pregnancy". The diet of 513 pregnant London women were recorded for 7 days during the first trimester of their pregnancy. Birthweight and nutrient intakes were found to be significantly correlated but only over the lower half of the birthweight range. The optimum birthweight range with the lowest perinatal and infant mortalities is 3,500-4,500 g and it is suggested that the nutrient intake of th 165 women who had babies in this optimum weight range provide tentative values for nutrient intake recommendations in anticipation of pregnancy, but are not claimed to be representative. The need for adjustments of recommendations for the individual, for example for a low body mass index, is discussed. A body mass index of 24 kg/m2 is recommended based on the median of the 165 women. 相似文献
28.
Clamp and sew techniques in thoracoabdominal aortic surgery using naloxone and CSF drainage 总被引:1,自引:0,他引:1
Surgical repair of thoracoabdominal (TAA) and thoracic aneurysm is challenging, with the potentials for high morbidity and mortality. There is no standardized operative approach. Operative management of TAA consists of simple clamp-and-sew techniques with adjuncts, cerebrospinal fluid (CSF) drainage, naloxone administration, and intraoperative hypothermia, to protect the spinal cord. The use of CSF drainage and naloxone administration has reduced paraplegia to 3.4%, compared with 21% when none of these adjunctive spinal cord measures were used. The authors discuss their operative strategy, surgical technique, and results at the University of Wisconsin Hospital and Clinics. 相似文献
29.
RF Lamont 《BJOG : an international journal of obstetrics and gynaecology》2006,113(S3):96-99
Over the past 15 years, the use of β-agonists has declined worldwide. Following the Royal College of Obstetricians and Gynaecologists guidelines in 2002, clinicians in the UK and beyond were faced with the dilemma of continuing to use β-agonists, desist from using tocolytic therapy completely or choosing to change to atosiban or calcium channel blockers (CCBs). While grade A level 1 evidence exists to show that atosiban is significantly more efficacious than placebo and significantly safer than β-agonists for the treatment of spontaneous preterm labour, the evidence for CCBs, such as nifedipine, is much less robust and no placebo-controlled trials have been performed. Published studies on nifedipine are largely investigator-led studies of small sample size, which lack sufficient power. As a result, most of the evidence has been based on meta-analyses of these studies, which look retrospectively at pooled data and are only as good as the quality of the studies included. In light of this, a tool was developed to produce a systematic review of studies on tocolytic effectiveness, which can and should be applied to all tocolytics and which considered both method- and topic-specific markers of quality. In the process of applying this tool to nifedipine, an extensive literature search identified 31 studies for a systematic review of the quality of nifedipine studies assessed by eight paired reviewers with wide experience in the subject of spontaneous preterm labour and preterm birth. Forty topic- and method-specific items of quality were assessed. The paucity of good quality studies of nifedipine used for the treatment of spontaneous preterm labour should be highlighted in meta-analyses or systematic reviews, which measure efficacy and should limit and influence the degree to which recommendations and guidelines are made on the basis of such studies. 相似文献
30.