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81.
Baclofen, a widely used antispastic agent, has been found to exist in two crystalline forms, the anhydrate and monohydrate. The aim of this study was (1) to identify and characterize these two solid phases of baclofen, and (2) to examine the processing-induced phase transformations associated with wet granulation of baclofen. Using multiple techniques (powder X-ray diffraction, thermal analysis, vibrational spectroscopy and water vapor sorption analysis), a structural relationship has been established between the anhydrate and monohydrate of baclofen. Thermal and variable-temperature powder X-ray diffraction data indicate that the monohydrate, which presumably belongs to the channel hydrate class, dehydrates at 60 degrees C with the formation of the anhydrate. Furthermore, the anhydrate to monohydrate transformation followed by optical microscopy was found to occur via a solvent-mediated route. During wet massing experiments, the critical moisture value for the hydrate formation under the conditions of the present study was identified using qualitative powder X-ray diffraction and Raman spectroscopy. Finally, the interconversion pathway between the two crystalline forms of baclofen was presented. The knowledge of this pathway provides better understanding and control of the solid state of baclofen during processing and storage.  相似文献   
82.
83.

Background

The aim of this study was to assess the role of middle cerebral artery peak systolic velocity (MCA-PSV), as measured by doppler ultrasound, in detecting foetal anaemia in Rh- isoimmunised pregnancies. Intra-uterine foetal blood transfusion was performed in such anaemic foetuses to tide over the crisis of foetal immaturity till considered fit for extra-uterine survival.

Methods

Rh-isoimmunised pregnancies reporting to a tertiary institute from 2003 to 2005, were screened by doppler ultrasound to estimate MCA-PSV to detect foetal anaemia. If the foetus developed MCA-PSV of more than 1.5 multiple of median (MoM) for the gestational age, foetal blood sampling through cordocentesis was performed to confirm foetal anaemia, followed by intrauterine foetal blood transfusion to all anaemic foetuses at the same sitting. Neonatal outcome was evaluated by recording gestational age at the time of delivery, duration of gestational time gained and need for blood transfusion in the neonatal period.

Results

A total of thirteen isoimmunised pregnancies were evaluated. Three pregnancies did not require in-utero foetal blood transfusion. Twenty-one intrauterine foetal blood transfusions were performed in the remaining ten patients. Five received blood transfusion in the neonatal period. Intra uterine foetal death occurred in one grossly hydropic foetus and favourable neonatal outcome was recorded in the rest.

Conclusion

The clinical outcome of these pregnancies justifies the use of doppler studies of MCA-PSV in detecting foetal anaemia and intra uterine foetal blood transfusion is the only hope of prolonging pregnancy and salvaging such foetuses.Key Words: Rh-isoimmunisation, Middle cerebral artery peak systolic velocity, Foetal anaemia, Foetal blood transfusion  相似文献   
84.
85.
目的:已有实验研究证明,移植骨髓来源内皮祖细胞可以促进球囊损伤后血管内皮的修复及抑制内膜的增生.那么移植骨髓来源内皮祖细胞对自体静脉移植术后静脉血管内皮修复和内膜增生是否起同样的作用?观察自体骨髓来源内皮祖细胞移植对自体静脉移植术后静脉桥血管再内皮化及内膜增生的作用。方法:实验于2007-01/08在北华大学附属医院内科实验室完成。实验室级别:P2级。①实验材料:6~8月龄雄性新西兰大白兔由解放军第二军医大学实验动物中心提供.体质量(2.5±0.5)kg,清洁级,实验过程中对动物处置符合动物伦理学标准。②实验方法:抽取成年兔骨髓分离制备骨髓单个核细胞,体外扩增法培养出骨髓来源内皮祖细胞.在培养第7天通过Ac-Dil-LDL、FITC-BS-1双染色及流式细胞仪检测CD34、CD133、FIK-1表达进行细胞鉴定,应用DAPI荧光染料体外标记培养7 d的骨髓来源内皮祖细胞、将成年新西兰大白兔23只随机分为细胞移植组(n=13)和对照组(n=10)进行自体左颈外静脉、颈总动脉移植术,在建模后第3天将DAPI标记的骨髓来源内皮祖细胞悬液经耳缘静脉植入细胞移植组动物体内,埘照组植入等量的PBS液③实验评估:细胞移植后4周.观察兔静脉移植段血管性及内膜厚度。结果:23只免均进入结果分析,无脱落:①通过体外扩增法培养的骨髓来源内皮组细胞,培养至7 d可见AC-Dil-LDI及FITC-BS-1双染色阳性细胞并表达CD34、CD133及FIK-1。②在呈绿荧光染色的血管内皮中可见有部分不均匀的散发蓝色荧光(DAPI标记细胞的细胞核)。③细胞移植组兔静脉血管内皮有DAPI标记的细胞.且内膜厚度明显低于对照组(P<0.05)结论:自体骨髓来源的内皮祖细胞移植可以促进损伤部位血管内皮的修复.并抑制内膜的过度增生。  相似文献   
86.
Structuring a safer donor-replacement program   总被引:1,自引:0,他引:1  
BACKGROUND: Replacement donors are more likely than volunteer donors to have positive or abnormal tests for transfusion-transmissible disease. In an effort to increase the donor pool, workers sought to identify a safer replacement-donor subgroup that may be acceptable for routine donations. STUDY DESIGN AND METHODS: In a retrospective review and cohort study, the replacement-donor effect was separated from the new- donor effect. The relative effect the replacement donor has on the risk of transfusion-transmissible diseases, donor retention, and frequency of returning donations was then quantified by comparison against the effect of repeat volunteer donors. RESULTS: The replacement donor had 3.1 times the risk and 0.72 times the donor retention rate and made 0.81 times as many returning donations as the repeat volunteer donor. The figures for the new-donor effect were similar. The two risks were additive, making a new replacement donor particularly hazardous. If replacement donations only from repeat replacement donors were considered, the donor risk and the number of donations per returning donor were made comparable to those for the general (combined) volunteer donor. CONCLUSION: The negative effect of the replacement donor is similar in magnitude to that of the new volunteer donor. A replacement-donation program targeting repeat replacement donors has an acceptable risk profile and may be a valuable adjunct to the collection of blood from general volunteer donors.  相似文献   
87.
88.
Objectives: To examine the effects of an individualized outdoor activity intervention carried out by volunteers on depressive symptoms among community-living older people with severe mobility limitations who have difficulties accessing the outdoors independently.

Methods: Secondary analyses of the ‘Volunteering, Access to Outdoor Activities and Wellbeing in Older People’ (VOW) data (ISRCTN56847832). VOW was a randomized single blinded two-arm controlled trial conducted in Jyväskylä, Finland, in 2009–2011. At baseline, 121 people aged 67–92 years with severe mobility limitations were interviewed at home and randomized into either an intervention or waiting list control group. Volunteers (n = 47) had retired from regular work and were trained for the study. A volunteer assisted the participant in attending recreational out-of-home activities once a week for three months. Depressive symptoms were assessed using the Center for the Epidemiological Studies Depression Scale (CES-D).

Results: In the intervention group the CES-D score did not change during the intervention (from 15.1 ± standard error 0.9 to 15.1 ± 0.9), while in the control group it increased from 17.0 ± 1.3 to 19.1 ± 1.4 (intervention effect p = .096). Among the subgroups with minor depressive symptoms at baseline (CES-D score 16–20), the CES-D score decreased in the intervention group and increased in the control group (p = .025).

Conclusion: A three-month outdoor activity intervention may improve mood among older people with severe mobility limitations. More randomized controlled trials of the topic are needed.  相似文献   

89.
Snipes  RG; Ways  K; D'Amico  CN; Sivam  G; Gray  TK; Cohen  MS 《Blood》1987,70(5):1639-1644
U937 cells respond to a variety of stimuli with increased differentiation as manifested by reduced growth, increased adherence, increased expression of several surface receptors, and increased capacity for phagocytosis and formation of reactive oxygen intermediates. In the present study the effects of lymphocyte conditioned media, recombinant interferon-gamma (IFN-gamma), and 1 alpha,25-dihydroxyvitamin D3 (1,25(OH)2D3) on the ability to form reactive oxygen intermediates by U937 cells were measured by using the luminol-dependent luminescence (LDL) assay. Neither 1,25(OH)2D3 alone nor IFN-gamma alone enhanced competence for phorbol myristate acetate- stimulated LDL. Cells were capable of moderate LDL after exposure to lymphocyte conditioned media, and this was enhanced by 1,25(OH)2D3 (10(- 8) mol/L) and other vitamin D metabolites at higher concentrations. This effect was not secondary to accelerated production of myeloperoxidase, which is important in the LDL assay. Enhanced phorbol myristate acetate-stimulated phosphorylation of a 48-kd substrate was observed in 32P-labeled intact cells treated with 1,25(OH)2D3 alone or in combination with IFN-gamma. Treatment of cells with IFN-gamma or lymphocyte conditioned media did not alter phosphorylation. These results support the concept that 1,25(OH)2D3 plays a role in phagocyte differentiation and activation beyond the effects of lymphokines. Protein kinase C-mediated phosphorylation reactions may be necessary for the ability of U937 cells to reduce O2 and required for maximal activity under some conditions of incubation.  相似文献   
90.
BACKGROUND AND AIM: The clinical value of oesophageal histology in non-complicated gastro-oesophageal reflux disease (GORD) is controversial. Our aim was to explore the role of histology in preoperative diagnosis and postoperative follow-up in GORD. METHODS: From 40 patients 2 histopathologists graded and scored 191 oesophageal biopsies in a blinded manner to evaluate inter- and intraobserver variation pre- and postoperatively. Correlation between preoperative histology and objective clinical findings (endoscopy, esophageal 24-hour pH monitoring, and manometry) was calculated as well. RESULTS: Pathologist I interpreted 16 (50%) preoperative biopsies as normal, 5 (16%) with mild, 4 (12.5%) moderate, and 7 (21.9%) severe reflux changes. Pathologist II interpreted 11 (35.5%) preoperative biopsies as normal, 11 (35.5%) with mild, 6 (19.4%) moderate, and 3 (9.7%) severe reflux changes. In preoperative biopsies, interobserver variation was 33.8% and intraobserver variation 9.7%. A positive correlation was detectable between preoperative endoscopic and morphologic findings; no correlation existed between either acid reflux or LES pressure and oesophageal morphology. Normal pH monitoring and fundic wrap were noted postoperatively in all cases. In postoperative histology no significant differences according to pathologist I existed when compared with preoperative changes: 22 normal (69%), 7 mild (22%), 1 moderate (3.1%), and 2 severe (6.3%). Compared to preoperative analysis, pathologist II interpreted 24 (77%, p = 0.001) of the postoperative findings as normal, 1 (3%, p = 0.003) as mild, 4 (12.9%, n.s.) as moderate, and 2 (6.5% n.s.) as severe reflux changes. In postoperative biopsies interobserver variation was 21.1% and intraobserver variation 5.6%. CONCLUSION: The role of oesophageal histology in preoperative diagnosis and postoperative follow-up of GORD may be considered limited.  相似文献   
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