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91.
C.K. Kasper J.B. Graham P.B.A. Kernoff M.J. Larrieu K.A. Rickard and Prof. P.M. Mannucci 《Vox sanguinis》1989,56(3):141-144
Since 1982, when the World Federation of Hemophilia first published a document on the state of the art of hemophilia diagnosis and care, there have been lights and shadows in this field. Although the widespread infection of hemophiliacs with the human immunodeficiency virus (HIV) contaminating clotting factor concentrates is still a threatening and formidable shadow, the gloomy picture brought about by the AIDS epidemic is partially lightened by spectacular improvements in therapy and diagnosis. Carrier detection and first-trimester prenatal diagnosis can now be performed accurately in most kindreds by analysis of DNA of the factor VIII or IX genes. An important step forward towards the elimination of the risk of blood-borne infections transmitted by plasma products was recently made through the application of virucidal methods to clotting factor concentrates. Since HIV appears more vulnerable to such methods than the hepatitis viruses, currently available concentrates can be considered substantially free from the risk of transmitting HIV infection. Even though transmission of hepatitis is much reduced but not totally abolished, virucidal methods are continuously being improved, so that it can be foreseen that concentrates will become safer and safer. Finally, factor VIII produced by recombinant DNA technology is undergoing the first clinical trials in hemophiliacs. Hopefully, it will free from the risk of transmitting infections and will be available in sufficiently large amounts to meet the need of hemophiliacs worldwide. In 1982, the World Federation of Hemophilia published a message on the status of diagnosis and treatment of hemophilia. Since then, hemophilia care has been complicated by widespread infection of hemophiliacs with human immunodeficiency virus (HIV).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
92.
To examine the effects of protein malnutrition on mast cells, rats were fed a protein-deficient diet (0.5% protein ad libitum) or normal diet (27% protein ad libitum or pair fed) for 16, 21, 27, or 57 d. Male rats in the different groups showed no significant differences in mast cell number or histamine content per mast cell. IgE binding sites as measured by flow cytometry were decreased in rats on the deficient diet. Even after stripping receptors of endogenous IgE and then labeling with fluorescent IgE, the difference remained, thus confirming the lower number of mast cell IgE receptors in rats maintained on the protein-deficient diet. 相似文献
93.
Lee WC Frossard LA Hagberg K Haggstrom E Brånemark R Evans JH Pearcy MJ 《Clinical biomechanics (Bristol, Avon)》2007,22(6):665-673
BACKGROUND: Direct anchorage of a lower-limb prosthesis to the bone through an implanted fixation (osseointegration) has been suggested as an excellent alternative for amputees experiencing complications from use of a conventional socket-type prosthesis. However, an attempt needs to be made to optimize the mechanical design of the fixation and refine the rehabilitation program. Understanding the load applied on the fixation is a crucial step towards this goal. METHODS: The load applied on the osseointegrated fixation of nine transfemoral amputees was measured using a load transducer, when the amputees performed activities which included straight-line level walking, ascending and descending stairs and a ramp as well as walking around a circle. Force and moment patterns along each gait cycle, magnitudes and time of occurrence of the local extrema of the load, as well as impulses were analysed. FINDINGS: Managing a ramp and stairs, and walking around a circle did not produce a significant increase (P>0.05) in load compared to straight-line level walking. The patterns of the moment about the medio-lateral axis were different among the six activities which may reflect the different strategies used in controlling the prosthetic knee joint. INTERPRETATIONS: This study increases the understanding of biomechanics of bone-anchored osseointegrated prostheses. The loading data provided will be useful in designing the osseointegrated fixation to increase the fatigue life and to refine the rehabilitation protocol. 相似文献
94.
95.
目的 分析儿童维生素D的营养状况及其与体成分的关系.方法 选取北京市怀柔区(北纬40.3°)7~11岁学龄儿童381名,于2008年3月采集静脉血并采用酶联免疫吸附试验(ELISA,英国IDS公司)测定血清中25-羟维生素D[25(OH)D]的浓度,双能X线吸收仪(DEXA,美国Norland公司)测定前臂及全身的体成分,分析维生素D与体成分的相关性.结果研究对象血清25(OH)D的平均浓度为(44.4±12.5)nmol/L,维生素D缺乏和不足率[血清25(OH)D≤50 nmol/L]达68.5%.男生血清25(OH)D浓度(46.3±13.3)nmol/L高于女生(42.0±11.1)nmol/L,差异有统计学意义(t=3.38,P<0.01).血清25(OH)D浓度与前臂近端、远端、全身及分部位中四肢的瘦体重呈正相关(r=0.13~O.19,P<0.05),与前臂近端、远端的体脂百分比呈负相关(r=-0.14,P<0.05;r=-0.11,P<0.05),均有统计学意义.调整年龄、性别、身高、体重等混杂因素后,与前臂近端、全身分部位中双下肢的瘦体重相关性仍有统计学意义(r=0.12~0.14,P<0.05).血清25(OH)D浓度与各部位体脂的相关性均无统计学意义.结论 维生素D缺乏在北京市郊区儿童中较为普遍,而维生素D营养状况对体成分,尤其对瘦体重有促进作用. 相似文献
96.
The effects of antioxidant supplementation during Percoll preparation on human sperm DNA integrity 总被引:20,自引:6,他引:20
Hughes CM; Lewis SE; McKelvey-Martin VJ; Thompson W 《Human reproduction (Oxford, England)》1998,13(5):1240-1247
The integrity of sperm DNA is crucial for the maintenance of genetic
health. A major source of damage is reactive oxygen species (ROS)
generation; therefore, antioxidants may afford protection to sperm DNA. The
objectives of the study were, first, to measure the effects of antioxidant
supplementation in vitro on endogenous DNA damage in spermatozoa using the
single cell gel electrophoresis (comet) assay and, second, to assess the
effect of antioxidant supplementation given prior to X-ray irradiation on
induced DNA damage. Spermatozoa from 150 patients were prepared by Percoll
centrifugation in the presence of ascorbic acid (300, 600 microM), alpha
tocopherol (30, 60 microM), urate (200, 400 microM), or acetyl cysteine (5,
10 microM). DNA damage was induced by 30 Gy X-irradiation. DNA strand
breakage was measured using the comet assay. Sperm DNA was protected from
DNA damage by ascorbic acid (600 microM), alpha tocopherol (30 and 60
microM) and urate (400 microM). These antioxidants provided protection from
subsequent DNA damage by X-ray irradiation. In contrast, acetyl cysteine or
ascorbate and alpha tocopherol together induced further DNA damage.
Supplementation in vitro with the antioxidants ascorbate, urate and alpha
tocopherol separately has beneficial effects for sperm DNA integrity.
相似文献
97.
标 题 应用ATⅡ受体拮抗剂抗高血压治疗作 者 KjeldsenSE,OmvikP. 参考文献 TidsskrNorLaegeforen,1996,116:504~507研究疾病 高血压病。目 的 评估氯沙坦对心血管死亡率及非致死性心肌梗死和非脑卒中发生率的影响,同时评估该药对充血性心力衰竭或心绞痛所致的总死亡率和住院率的影响,以及长期应用氯沙坦对发生新诊断糖尿病的影响。设 计 随机、三盲、对照研究。病人资料 8300例年龄55~80岁、收缩压在160~200mmHg、舒张压在95~115mmHg的高血压患者,ECG上有左室… 相似文献
98.
BACKGROUND: Previous studies have implicated emotional suppression, in particular suppression of anger, in the onset and progression of breast cancer. Many of these studies used non-standardized measures and failed to control for the effects of age and/or possible knowledge of diagnosis. The present study aimed to avoid these methodological errors in investigating the relationship of emotional suppression to a diagnosis of breast cancer in a large mammography screened population. METHOD: Data were collected from 1151 women with suspicious mammograms recalled to a breast screening programme. Prior to multidisciplinary assessment women were asked to complete the Courtauld Emotional Control Scale. Imaging assessment outcome data and biopsy results were collected. RESULTS: Fifteen per cent of this population subsequently were diagnosed with breast cancer. There were no significant associations between a cancer outcome and emotional suppression before or after the highly significant effect of age was taken into account. CONCLUSIONS: These results suggest that suppression of emotion may not be relevant to the development of breast cancer. Its role in the progression of existing disease requires clarification. 相似文献
99.
Ketai LH; Williamson MR; Telepak RJ; Levy H; Koster FT; Nolte KB; Allen SE 《Radiology》1994,191(3):665
100.
A total of 140 sets of abdominal radiographs were reviewed independently by four qualified diagnostic radiologists. The degree of interobserver agreement was determined by calculating kappa values for 19 commonly used radiographic signs and diagnoses. There was fair to excellent interobserver agreement for 11 signs and diagnoses and poor agreement for the remaining eight. The signs and diagnoses for which agreement is poor cannot be considered reliable and include particularly large bowel obstruction and nonspecific gas pattern. 相似文献