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121.
122.
Owning the tooth: exploring the ethical and legal issues relating to the use of extracted human teeth in dental education in Australia 下载免费PDF全文
Extracted human teeth have been used to practice operative techniques for a very long time. As a natural surrogate for a live tooth in vivo, their use has traditionally been very important for the development of skills in trainee dentists, as well as their qualified colleagues who wish to practise existing or new skills. As synthetic alternatives develop greater authenticity, alongside a society in which many retain their natural dentition well into old age, the current paradigm relating to how extracted teeth in dental education are used needs to be revisited. An ethical and legal dilemma that must be addressed within dental education relates to where and how teeth may be sourced. This article will seek to question whether there is a legal or ethical requirement to gain consent for the use of extracted teeth from patients, as well as exploring the status of whether extracted dental tissue can be considered to be the property of either patient or surgeon. Whilst synthetic alternatives are being utilized more frequently in education, it is unlikely that they will completely replace extracted natural teeth in the immediate future. It is therefore imperative that their use complies with legal doctrine and contemporary ethical thought. 相似文献
123.
目的探讨急性脑出血患者卒中相关性肺炎(SAP)发生的危险因素,以便早期干预。方法选择急性脑出血患者196例为研究对象,其中发生SAP 82例为病例组,未发生SAP 114例为对照组。对两组的年龄、性别、心肺疾病史、GCS评分、吞咽困难、心率、血压、白细胞计数、脑出血量、鼻饲、使用胃黏膜保护剂和手术等共计23项予以比较分析。所得资料在单因素分析的基础上,又作多因素Logistic回归分析。结果急性脑出血SAP的患病率为41.837%。收缩压升高(优势比1.072,95%可信区间1.007~1.141,P=0.029)、白细胞计数增加(优势比1.331,95%可信区间1.009~1.756,P=0.043)、脑出血量增多(优势比1.079,95%可信区间1.019~1.142,P=0.010)、有心肺疾病(优势比12.275,95%可信区间1.210~124.545,P=0.034)、吞咽困难(优势比12.937,95%可信区间1.918~87.250,P=0.009)和鼻饲(优势比19.217,95%可信区间1.307~282.651,P=0.031)均促进发病。而使用胃黏膜保护剂(优势比0.157,95%可信区间0.031~0.790,P=0.025)和实施手术(优势比0.012,95%可信区间0.000~0.294,P=0.007)阻止发病。结论收缩压、白细胞计数增加、脑出血量增高、有心肺疾病、吞咽困难和鼻饲是急性脑出血发生SAP的危险因素;而使用胃黏膜保护剂和实施手术为其保护因素。 相似文献
124.
目的:优选小白蒿蒙医炮制工艺,并观察其饮片安全有效性。方法:以炮制品绿原酸含量为主要指标并参考槲皮素含量进行正交试验,以考察炒制温度、时间和药材粒度的影响,确定最佳工艺;采用小白鼠急性毒性实验,断尾实验测定出血时间,眼眶静脉丛取血测定凝血时间,断头采全血计数血小板总数,评价安全有效性。结果:本品在270℃温度下翻动炒制20 min效果最佳,经方差分析证明炒制温度、时间和粒度因素对所监测的两种成分的含量均没有显著影响;小白蒿炮制后可缩短小白鼠的出血时间,显著增高血小板计数。结论:小白蒿经过合理的炒制后,可提高其安全性和止血药效,为验证传统蒙药小白蒿用药理论,提供了参考依据。 相似文献
125.
126.
S Ghaffari SA Mahdavi Z Moulana S Mouodi H Karimi-Nia M Bayani N Kalantari 《Iranian Journal of Parasitology》2012,7(3):82-88
Background
Malaria is one of the most important parasitic diseases in tropical and temperate regions. The aim of this study was to determine the trend of malaria in Mazandaran Province, northern Iran during 1997-2012.Methods
This retrospective study was conducted from 1997 to 2012. The population''s study was individuals who registered at health centers of Mazandaran Province. Peripheral blood smear were prepared for each case, stained with Giemsa and examined by light microscope. In addition to demographic data, other parameters including Slide Positive Rate (SPR), Annual Parasite Incidence (API) and Annual Blood Examination Rate (ABER) were analyzed.Results
In total, 844 cases of malaria were reported. Plasmodium vivax was predominant species with 821 cases (97.4%). The number of malaria cases increased from 1997 to 2005 and then decreased to 3 cases in 2011. Some cities had not reported any cases during last three years. The highest infection rate, 163(20.07%), was seen in 2001-02. The SPR had the highest value (0.54%) in 2004-05. The maximum API and ABER were observed in 2001-02 and 1997-98. 641(75.9%) of cases were imported from hyperendemic areas such as Afghanistan and South-eastern Iran and 94 (11.1%) malaria patients were recorded as introduced cases. The highest infection rate of malaria (21.3%) was seen in Babolsar.Conclusion
Extensive malaria control should be continued to Mazandaran to become malaria-free region and in prevention of re-introduction stage. 相似文献127.
It has previously been shown that monolayer cultures derived adherent cells (MDAC), apparently consisting of fibroblasts, macrophages, epithelioid cells, and fat cells, can support long-term stem cell proliferation in vitro. In the present study, the hematopoietic support capability of murine MDAC monolayers was confirmed and the cultured cells further characterized with respect to the following properties: esterase I activity, complement (C3) receptors, IgG (Fc) receptors, colony stimulating activity (csa) production, and collagen synthesis. The cultures were also examined immunohistochemically to localize fibronectin, laminin, and collagen synthesis and to identify the collagen subtypes synthesized. MDAC morphology was as described in previous studies, although fat cells were few in number. It was found that MDAC included some cells with esterase I activity and C3 receptors. Fc receptors were not, however, detected, nor did the cultures produce csa, indicating that mononuclear phagocytes were not present. MDAC synthesized collagen types I and III and also fibronectin. Staining for epithelial basement membrane proteins (collagen types IV and V and laminin) was negative. The results indicate that the vast majority of these cultured MDAC were fibroblasts. 相似文献
128.
The kidneys in paroxysmal nocturnal hemoglobinuria 总被引:6,自引:0,他引:6
Long-term study of 21 PNH patients revealed an unexpectedly high incidence of functional and anatomic renal abnormalities. Most patients demonstrated varying degrees of hematuria and proteinuria distinct from hemoglobinuria. Evaluation of renal function revealed hyposthenuria, abnormal tubular function, and declining creatinine clearance. Radiologically these patients had enlarged kidneys, cortical infarcts, cortical thinning, and papillary necrosis which were confirmed by autopsy studies. Hypertension developed in eight patients. Urinary tract infection was uncommon. The renal findings bear striking similarity to those of sickle cell anemia. Contrary to the usual opinion, out studies clearly showed evidence of widespread renal pathology in PNH most likely due to repeated microvascular thrombosis similar to the venous thrombosis involving other organs in this disorder. 相似文献
129.
Thrombocytopoietic properties of oncostatin M 总被引:1,自引:2,他引:1
Oncostatin M (OM) is a 28-kD glycoprotein that exhibits a panoply of biologic effects. Based on histologic observations of increased splenic megakaryocytes in nude mice implanted with an OM-secreting cell line, the thrombocytopoietic properties of OM in mice were investigated in culture and in vivo. Alone, OM did not induce megakaryocytic colony formation, but in combination with murine interleukin-3 (IL-3), OM markedly enhanced colony formation. The effects of OM on colony formation were similar to those of IL-6. OM alone augmented acetylcholinesterase in short-term marrow cultures. In normal mice, the administration of OM augmented platelet counts without increasing other circulating blood cell counts. The increment in counts exceeded that observed with IL-6. The kinetics of the OM response suggested that maximal increases in platelets occurred 3 days after the cessation of OM administration, irrespective of the duration of administration. In irradiated mice, OM administration accelerated platelet recovery and prevented the decrease in red blood cells observed in irradiated control animals. The data show that OM behaves as a megakaryocytic maturation factor in vitro and augments platelet production in vivo. Based on these animal data, OM may have potential clinical utility as a thrombocytopoietic agent. 相似文献
130.
Ronday HK; Te Koppele JM; Greenwald RA; Moak SA; De Roos JA; Dijkmans BA; Breedveld FC; Verheijen JH 《Rheumatology (Oxford, England)》1998,37(1):34-38
The plasminogen activation system is one of the enzyme systems held
responsible for bone and cartilage degradation in rheumatoid arthritis
(RA). In this study, we evaluated the effect of tranexamic acid (TEA), an
inhibitor of plasminogen activation, on urinary collagen cross-link
excretion and radiological joint damage in rat adjuvant arthritis (AA) and
on urinary collagen cross-link excretion in patients with RA. In the animal
study, adjuvant arthritis was induced in male Lewis rats. From day 7
onward, high-dose TEA (500 mg/kg body weight, once daily) or placebo was
administered orally. Study groups consisted of TEA-treated normal rats (C +
TEA), placebo-treated normal rats (C + plac), AA rats treated with TEA (AA
+ TEA) or with placebo (AA + plac). To monitor joint destruction, urinary
collagen cross-link excretion (pyridinoline, HP; deoxypyridinoline, LP) was
measured by high-performance liquid chromatography at days 14 and 21.
Radiological evaluation of joints was performed at day 21. In the patient
study, TEA was administered to nine patients with RA as adjuvant medication
(approximately 20 mg/kg body weight, three times daily) for 12 weeks.
Urinary HP and LP excretion levels were measured before and during TEA
treatment, and 4 weeks after the cessation of TEA treatment. In AA + TEA
rats, a significant reduction of HP and a tendency towards a reduction of
LP excretion were found compared with AA + plac rats (P < 0.05), at day
14, whereas the HP/LP ratio did not change. No difference was observed in
HP, LP excretion, HP/LP ratio and radiological damage score between the
TEA- and placebo-treated AA rats at day 21. In RA patients, a significant
reduction of HP and LP excretion was found during the TEA treatment period
(P < 0.05). After the cessation of TEA treatment, HP and LP excretion
increased towards baseline levels. No effect on disease activity was
observed. The plasmin antagonist TEA reduced the excretion of collagen
pyridinoline cross-links in both experimental and rheumatoid arthritis. As
such, this study not only supports the involvement of the plasminogen
activation system in the destructive phase of arthritis, but also suggests
a beneficial effect of therapeutic strategies directed against inhibition
of matrix proteolysis.
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