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排序方式: 共有481条查询结果,搜索用时 15 毫秒
91.
92.
Mortality associated with acute watery diarrhea, dysentery and persistent diarrhea in rural North India 总被引:1,自引:0,他引:1
Mortality associated with diarrhea was investigated in a longitudinally followed cohort of children under six years of age in rural North India. During the follow-up, 1663 episodes of diarrhea and 23 diarrhea related deaths were recorded in 1467 children followed up for 20 months. The case fatality rate was 0.56% for acute watery diarrhea, 4.27% for dysentery and 11.94% for non-dysenteric persistent diarrhea. Most of the episodes lasted less than a week; 5.2% became persistent (duration > 14 days). The case fatality rate was similar in episodes of one and two weeks'duration (0.64% and 0.8%) and increased to 13.95% for persistent episodes. Of the total 86 persistent episodes, 22.1% were dysenteric; the case fatality rate for such dysenteric persistent episodes was 21.1% and for watery persistent diarrhea 11.4%. Diarrheal attack rates were similar among different nutritional groups, but diarrheal case fatality rates progressively increased with increasing severity of malnutrition, these were 24 times higher in children with severe malnutrition (7.48%) compared to those normally nourished (0.31%). With availability and use of oral rehydration therapy, dysentery and persistent diarrhea emerge as major causes of diarrhea related mortality, with underlying malnutrition as a key associated factor. 相似文献
93.
The role of feeding breast milk, unmodified bovine milk or adapted infant formula during acute diarrhoea in protecting against or causing persistence of the episodes was investigated in a population-based case control study in an urban area of north India. After adjustment for confounding variables, exclusive breast-feeding was associated with an odds ratio of 0.06 (95% CI 0.002-2.1), a 16.5 times lower odds in favour of developing persistence of an episode. Infants fed unmodified bovine milk in addition to breast milk had an odds of 2.5 times (95% CI 1.0-9.9) in favour of developing persistence of acute diarrhoea ( p = 0.04). In infants receiving unmodified bovine milk and no breast milk, this odds ratio was 11.1 (95% CI 1.0-228.8) ( p = 0.05). This study indicates that promoting exclusive breastfeeding may reduce the persistence of diarrhoea over and above its effect in decreasing the incidence of acute diarrhoea. In urban areas of the developing countries where working mothers often use milk supplementation beyond the age of three months, our findings suggest that use of adapted spray dried formula may be safer than unmodified bovine milk with respect to the risk of developing persistent diarrhoea. 相似文献
94.
Cancers of the oral cavity, pharynx, and esophagus are now suspected to have common etiologic factors and have been grouped together as “upper aerodigestive” cancers. Since this grouping is of relatively recent origin there have been no epidemiological studies on this group among Armed Forces personnel. 114 cases of upper aerodigestive cancers and an equal number of controls were studied. The largest number of cases were in the age group of 40–49 years with male preponderance. Lower level of education, smoking, quid chewing, and alcohol use were found to be the major risk factors for these cancers. A dose response relationship was observed for smoking, quid chewing and alcohol intake.KEY WORDS: Neoplasms, Smoking, Quid chewing, Alcohol 相似文献
95.
Femoral head avascular necrosis: correlation of MR imaging, radiographic staging, radionuclide imaging, and clinical findings 总被引:39,自引:0,他引:39
Mitchell DG; Rao VM; Dalinka MK; Spritzer CE; Alavi A; Steinberg ME; Fallon M; Kressel HY 《Radiology》1987,162(3):709-715
To better correlate the appearance of avascular necrosis (AVN) of the femoral head on magnetic resonance (MR) images with the stage of disease, MR images of 56 proved AVN lesions were compared with staging from corresponding radiographs (n = 56), Tc-99m scans (n = 41), and grade of symptoms (n = 28). Fractures complicating AVN were seen in 28 (50%) of 56 radiographs (radiographic stages III-V). With long repetition (TR) and echo delay (TE) times, a characteristic "double line sign" consisting of high signal intensity inside a low-intensity peripheral rim was seen in 45 lesions (80%). The central region within the rim was isointense with marrow fat on both short and long TR and TE images in 20 (71%) of 28 lesions uncomplicated by fracture (stages I-II) but in only four (14%) of 28 stage III-V lesions (P less than .001). Symptoms were least severe in lesions isointense with fat and most severe in lesions with low-signal central regions at short and long TRs and TEs. The peripheral double line sign on long TR/TE images may add specificity to the diagnosis of AVN by MR imaging. A chronologic pattern of central MR signal features is presented which may allow staging of AVN by MR imaging. 相似文献
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Dercksen MW; Gerritsen WR; Rodenhuis S; Dirkson MK; Slaper-Cortenbach IC; Schaasberg WP; Pinedo HM; von dem Borne AE; van der Schoot CE 《Blood》1995,85(11):3313-3319
Adhesion molecules play a role in the migration of hematopoietic progenitor cells and regulation of hematopoiesis. To study whether the mobilization process is associated with changes in expression of adhesion molecules, the expression of CD31, CD44, L-selectin, sialyl Lewisx, beta 1 integrins very late antigen 4 (VLA-4) and VLA-5, and beta 2 integrins lymphocyte function-associated 1 and Mac-1 was measured on either bone marrow (BM) CD34+ cells or on peripheral blood CD34+ cells mobilized with a combination of granulocyte colony- stimulating factor (G-CSF) and chemotherapy. beta 1 integrin VLA-4 was expressed at a significantly lower concentration on peripheral blood progenitor cells than on BM CD34+ cells, procured either during steady- state hematopoiesis or at the time of leukocytapheresis. No differences in the level of expression were found for the other adhesion molecules. To obtain insight in which adhesion molecules may participate in the homing of peripheral blood stem cells (PBSCs), the number of CD34+ cells expressing these adhesion molecules present in leukocytapheresis material was quantified and correlated with hematopoietic recovery after intensive chemotherapy in 27 patients. The number of CD34+ cells in the subset defined by L-selectin expression correlated significantly better with time to platelet recovery after PBSC transplantation (r = - .86) than did the total number of CD34+ cells (r = -.55). Statistical analysis of the relationship between the number of CD34+L-selectin+ cells and platelet recovery resulted in a threshold value for rapid platelet recovery of 2.1 x 10(6) CD34+ L-selectin+ cells/kg. A rapid platelet recovery (< or = 14 days) was observed in 13 of 15 patients who received > or = 2.1 x 10(6) CD34+ L-selectin+ cells/kg (median, 11 days; range, 7 to 16 days), whereas 10 of 12 patients who received less double positive cells had a relative slow platelet recovery (median, 20 days; range, 13 to 37 days). The L-selectin+ subpopulation of CD34+ cells also correlated better with time to neutrophil recovery (r = - .70) than did the total number of reinfused CD34+ cells (r = -.51). However, this latter difference failed to reach statistical significance. This study suggests that L-selectin is involved in the homing of CD34+ cells after PBSC transplantation. 相似文献
99.
目的:应用电生理检测指标评价碱性成纤维细胞生长因子复合缓释降解膜对周围神经再生的影响。方法:实验于2005-03/11在沈阳医学院奉天医院实验室完成。①实验材料:碱性成纤维细胞生长因子复合缓释降解膜:主要成分为碱性成纤维细胞生长因子、维生素C抑制剂、明胶、壳聚糖。②实验分组:大耳白兔60只,按随机数字表法分为实验组和对照组,每组30只。异体正中神经制备:每组兔分6次取正中神经,每次取5只兔的正中神经,分别切除双侧正中神经各2.5cm,用受体动物血浆浸泡20min、-196℃液氮冷存21d、室温下复温。手术方法:麻醉后暴露双侧上臂正中神经主干,在相应一致神经部位切除2.5cm,用复温后的异体正中神经缝接。实验组神经缝接处包裹碱性成纤维细胞生长因子复合缓释降解膜,对照组不包膜。③实验评估:术后8,13,26周采用Keypoint肌电诱发电位仪测定运动神经传导速度和复合肌肉动作电位波幅。采用Luzex-F图像分析仪测定移植神经近段和远段的锇酸髓鞘染色横断面标本上有髓神经纤维数量。结果:①运动神经传导速度:术后8,13,26周实验组运动神经传导速度明显快于对照组[分别为(21.62±2.81),(13.16±1.81)m/s;(40.83±3.66),(21.71±2.40)m/s;(50.41±4.84),(31.96±3.17)m/s],两组间差异有非常显著性意义(t=3.51,3.69,3.88,P<0.001)。②复合肌肉动作电位波幅:术后8,13,26周实验组复合肌肉动作电位波幅则明显高于对照组[分别为(1.47±0.16),(0.83±0.07)mV;(4.82±1.27),(2.66±0.31)mV;(14.55±4.16),(8.63±3.36)mV],两组间差异有显著性意义(t=2.34,2.48,2.66,P<0.05)。③有髓神经纤维数量:实验组术后13周神经近段和远段有髓神经纤维比例为2.5∶1,术后26周比例为1.2∶1;而对照组相应时间点有髓神经纤维比例分别为7.2∶1和2.2∶1。结论:神经传导速度和复合肌肉动作电位波幅检测结果提示碱性成纤维细胞生长因子复合缓释降解膜有促进周围神经再生的作用。 相似文献
100.