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21.
Cecatti JG Souza JP Parpinelli MA de Sousa MH Amaral E 《Reproductive Health Matters》2007,15(30):125-133
The occurrence of complications during pregnancy depends less on the degree of human development than differences in the way complications in pregnancy are detected and managed. It is the quick diagnosis and correct management that really contribute to the enormous differences in maternal mortality ratios between countries and regions. Understanding of the determinants of maternal mortality may be improved by studying cases of severe maternal morbidity. In this paper, various approaches to the concept of severe maternal morbidity and near-misses are discussed, and the relationship between these and maternal deaths. Although no consensus has been reached on a strict definition of near-miss or severe maternal morbidity, we show that the definitions used may be tailored to support diverse objectives, including monitoring progress, epidemiological surveillance and auditing of health care. We conclude that the versatility of the concept, the greater frequency of cases available for study and the possibility of interviewing the survivors of severe complications all support the value of studying severe maternal morbidity to help guide local efforts to reduce maternal mortality. Although this may almost be a reality in developed countries, it continues to represent an important and difficult challenge to overcome in places where its benefits would be most evident. 相似文献
22.
Asma Arabi Mariana Salamoun Hajar Ballout Ghada El-Hajj Fuleihan 《Journal of clinical densitometry》2005,8(3):261-266
Studies have shown a high correlation between measurements of bone mineral density (BMD) obtained on differentdual-energy X-ray absorptiometry machines. Challenger osteodensitometers (Diagnostic Medical System [DMS],Montpellier, France) are becoming widely used but little is known about their clinical performance. The aim of this study was to compare BMD measurements and the resulting patient classification based on T-scores obtained on a DMS Challenger device to those obtained on Hologic 4500A (Bedford, MA) device. Fifty-three volunteers were studied.The BMD of the spine and of the hip were simultaneously measured on both densitometers. BMD values obtained on the Challenger were significantly higher than those obtained with the Hologic QDR4500 (p<0.001). The correlations coefficients between the Hologic QDR4500 and the DMS Challenger measured BMDs were r=0.70 at the femoral neck, r=0.70 at the trochanter, and r=0.83 at the spine (p<0.001). Among the 35 postmenopausal women, there was discordance in the WHO T-score-based classification in 28 subjects (80%) at the spine, 18 subjects (52%) at the femoral neck, and 14 subjects (42%) at the trochanter. The intermachine agreement was low: The kappa score was -0.10 at the spine, 0.2 at the femoral neck, and 0.3 at the trochanter. In conclusion, this study cautions against the use of non established densitometers that leads to underdiagnosis of patients and, subsequently, to inappropriate treatment strategies. 相似文献
23.
Mariana Villarroel Dorrego Paul M. Speight A. William Barrett 《Journal of oral pathology & medicine》2006,35(5):268-273
BACKGROUND: CD40 has a role in the regulation of immune responses, cell proliferation and migration, and apoptosis. Little is known of its distribution in oral mucosal pathology. METHODS: Oral keratinocyte lines were tested for CD40 protein by Western blotting. Immunohistochemistry was used to stain paraffin sections of oral mucosa in health and in inflammatory, reactive, dysplastic and malignant disease. RESULTS: Western blotting confirmed the presence of CD40 in oral keratinocytes. CD40 was generally expressed by keratinocytes in the basal layer, with variable parabasal expression. Langerhans cells also stained positively. Expression was lost in nine of 33 (27%) epithelial dysplasias, seven of which were severe. Eighty-one percent of well, 69% of moderately and 50% of poorly differentiated oral squamous cell carcinomas (OSCC) expressed CD40. Overall, 45 of 65 (69%) OSCC were positive. The pattern of expression was unrelated to tumour differentiation. CONCLUSION: CD40 expression by basal and parabasal oral keratinocytes is physiological. Expression is lost in approximately one-third of oral epithelial dysplasias and OSCC. The significance of such loss remains unknown, but may be related to immunological or other abnormalities of keratinocyte homeostasis. 相似文献
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We evaluated the influence of individually estimated portion sizes on the estimate of nutrient related risk of colorectal cancer, using data from a Portuguese hospital based case-control study on diet and colorectal cancer. A total of 100 patients with colorectal adenocarcinoma (aged 15-92 years) and 211 controls (aged 36-89 years) were included. Two data sets were created for nutrient analysis, the first one allowed estimates of food intake using data on portion size as collected with visual aids during the interview. The second estimate substituted respondents' estimate with a standard portion size, as used in the semi-quantitative (SQ) food frequency approach. The two analytic approaches yielded similar energy and nutrient intakes in cases and controls. The percent range of concordance is acceptable, in the same quartile varying from 44 to 82% (mean: 56%) and very good in the same or adjacent (+/-1) quartile (mean: 91%, range: 85-97%). The two estimates lead to a similar pattern of multivariate odd's ratio, however the SQ estimates resulted in more significant findings. We conclude that little extra information is gained by including individual portion size information when assessing diet-related risk of colorectal cancer. 相似文献
26.
Jonas Bergstrm Mahmood Ahmed Jian Li Tashfeen Ahmad Andris Kreicbergs Mariana Spetea 《Journal of orthopaedic research》2006,24(6):1193-1199
Using immunohistochemical and biochemical techniques, the occurrence of endogenous opioid peptides and their receptors in normal rat bone and joint tissues was investigated. Opioid receptors were detected, quantified, and characterized in homogenates from capsule/synovium and periosteum using radioligand binding assays. Receptor binding of the nonselective opioid [3H]naloxone to tissue homogenates was stereospecific and saturable, showing similar characteristics to that of brain tissue, although with lower binding capacities. By immunohistochemistry, the neuronal occurrence of four different enkephalins was demonstrated in synovium, bone marrow, periosteum, and juxta-articular bone, whereas no neuronal dynorphin immunoreactivity was detected. Double-staining studies disclosed that enkephalins coexisted with substance P in primary afferent fibers. The applied techniques can be used to assess changes in the distribution of endogenous opioids and their receptors in joint tissues in conditions associated with pain and inflammation. The endogenous opioid system now demonstrated might be targeted and exploited therapeutically to obtain peripheral control of symptoms in joint disorders. 相似文献
27.
28.
Rapid production of Candida albicans chlamydospores in liquid media under various incubation conditions. 总被引:1,自引:0,他引:1
Zavalza-Stiker Alicia Ortiz-Saldivar Blanca García-Hernández Mariana Castillo-Casanova Magdalena Bonifaz Alexandro 《Nippon Ishinkin Gakkai Zasshi》2006,47(3):231-234
The production of chlamydospores is a diagnostic tool used to identify Candida albicans; these structures also represent a model for morphogenetic research. The time required to produce them with standard methods is 48-72 hours in rice meal agar and tensoactive agents. This time can be shorted using liquid media such as cornmeal broth (CMB) and dairy supplements. Five media were tested: CMB plus 1% Tween-80, CMB plus 5% milk, CMB plus 5% milk serum, milk serum, and milk serum plus 1% Tween-80, under different incubation conditions: at 28 degrees C and 37 degrees C in a metabolic bath stirring at 150 rpm, and at 28 degrees C in a culture stove. The reading time points were established at 8 and 16 hours. The best results were obtained at 16 hours with CMB plus 5% milk under incubation at 28 degrees C and stirring at 150 rpm. The next most efficient methods were CMB plus 5% milk serum and CMB plus 1% Tween-80, under the same incubation conditions. The other media were ineffective in producing chlamydospores. The absence of stirring at 28 degrees C prevented the formation of chlamydospores within the set time points, and incubation at 37 degrees C decreased their production. This paper reports that the time to form C. albicans chlamydospores can be reduced. 相似文献
29.
30.
Shamil D. Akhmedov M.D. Euvgenily V. Krivoschekov M.D. Mariana V. Pekarskaya M.D. Alexander L. Krylov M.D. Zhanna V. Vesnina M.D. Vladimir I. Chernov M.D. Alexander M. Chernyavskiy M.D. Yuriy Y. Vechersky M.D. Rostislav S. Karpov M.D. Edward A. Nechaev M.D. Vikenty V. Pekarski M.D. 《Journal of cardiac surgery》1995,10(5):573-579
Thirty-five cardiomyoplasty procedures were performed in five patients with dilated and 30 patients with ischemic cardiomyopathies. Russian-made cardiomyostimulators (CMS) were implanted in these patients. Twenty-one patients underwent a one-step procedure using a left thoracotomy for cardiomyoplasty, while in 14 patients, a two-step procedure that included a mid-line sternotomy was carried out. During the average follow-up period of 9 ± 2.1 months, studies were carried out that showed in survivors improved clinical functional status and decreased heart failure symptoms. Evidence of revascularization of the ischemic myocardium from the latissimus dorsi muscle (LDM) wrap was obtained by angiography and radioactive scintigraphy. In five patients, the CMS had to be removed due to complications, and in all these patients, their clinical functional status deteriorated following the cessation of cardiomyostimulation. 相似文献