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排序方式: 共有172条查询结果,搜索用时 31 毫秒
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In 1985 a ‘pulse immunization’ project was begunin southern Mozambique, to overcome the difficulties of deliveringimmunization services in rural areas. The project was closelymonitored in order to determine whether this strategy wouldbe appropriate on a national level. Major inputs were in trainingof both health workers and volunteers, and the development ofa system for communications and defaulter tracing via Mozambique'snetwork of grassroots organizations. By 1987 the project hadachieved 60% coverage of fully immunized children in safe ruralareas of the province, having reduced dropout rates betweenfirst and third doses of DPT/OPV from 49% to 11%. This paperdescribes the process of project development through situationanalysis, project design, implementation, monitoring and evaluation.Conclusions are drawn which may be relevant to other programmesin their attempts to accelerate immunization coverage in a sustainableway.  相似文献   
3.
We report a rare case of early-stage endometrial adenocarcinoma in a 22 year old nullipara with polycystic ovaries undergoing conservative treatment. Pretreatment evaluation including tumour grade, depth of myometrial invasion, tumour size, hormone receptor status and flow cytometric analysis indicated a favourable prognosis. The patient underwent repeat endometrial curettage and a 6 month period of therapy with megestrol acetate and tamoxifen. A combination contraceptive pill was then prescribed to ensure withdrawal of the menstrual cycle thereafter. Now, 1 year after the last curettage, there is no evidence of disease. During the treatment period, hysteroscopy allowed for a more precise approach in panoramically examining the tumour nest in the endometrial cavity, and the subsequent endometrial response to hormone therapy. Laparoscopy using bulldog clamps applied to the isthmic portion of the Fallopian tubes prevented i.p. spread of endometrial tissue from retrograde regurgitation during hysteroscopy. Laparoscopic ovarian electrocautery resulted in the reduction of abnormal hypervascularization on the surface of polycystic ovaries postoperatively but caused a peri-ovarian adhesion complication. It is interesting that this case posed a unique opportunity to demonstrate the tumour regression under the assistance of laparoscopy and hysteroscopy.   相似文献   
4.
FT Chew  DYT Goh  BC Ooi  R Saharom  JKS Hui  BW Lee 《Allergy》1999,54(4):320-329
BACKGROUND: Air-pollution levels have been shown to be associated with increased morbidity of respiratory diseases. METHODS: Data for ambient air-pollutant levels, meteorologic factors, and hospitalization or emergency room (ER) visits for acute asthma in Singapore children over a 5-year period (1990-4) were obtained and analyzed for associations by time-series methods. RESULTS: Throughout this period, the annual mean and 24-h mean levels for sulfur dioxide (SO2), nitrogen dioxide (NO2), and total suspended particles (TSP) and maximum 1-h daily average for ozone were generally within the air-quality guidelines established by the World Health Organization (WHO). However, positive correlation between levels of each of these pollutants and daily ER visits for asthma was observed in children aged 3-12 years, but not among adolescents and young adults (13-21 years old). The association with SO2 and TSP persisted after standardization for meteorologic and temporal variables. An adjusted increase in 2.9 ER visits for every 20 microg/m3 increase in atmospheric SO2 levels, lagged by 1 day, was observed on days when levels were above 68 microg/m3. With TSP, an adjusted increase of 5.80 ER visits for every 20 microg/m3 increase in its daily atmospheric levels, lagged by 1 day, was observed on days with levels above 73 microg/m3. Similar results were also obtained after controlling for autocorrelation by time-series analysis. CONCLUSIONS: These associations were observed even though the overall levels of all pollutants were generally within the air-quality guidelines established by the WHO. These findings suggest that asthmatic children are susceptible to increased levels of air pollutants, particularly SO2 and TSP, although the ambient levels are generally within "acceptable" ranges.  相似文献   
5.
Despite the well-known toxicity of aluminium in chronic renal failure, a solid database on its biokinetics has been difficult to establish. A highly sensitive method using (26)Al as tracer and accelerator mass spectrometry (AMS) for detection was used. No perturbing background and saturation effects were taken into account using a delta function input of aluminium in time. Aluminium absorption, distribution, speciation and excretion in six healthy volunteers and in two patients with chronic renal failure were investigated following administration of a single oral or i.v. dose of (26)Al. Serial samples of blood and urine were taken. In a speciation study, the time dependence of the binding of (26)Al to low-molecular weight molecules in serum was investigated. The measured data were compared and interpreted with simulations in an open compartmental model. Fractional absorption, distribution, excretion and time constants for the aluminium transport were determined. Typical intestinal absorption rates for AlCl(3) were found to be in the range of 10(-3). The ultrafiltrable percentage of aluminium in serum of one volunteer was estimated to be 5.6+/-0.8%. Differences between healthy volunteers and patients with chronic renal failure were deduced. The employed method using (26)Al and ams has proven to be highly sensitive for investigations of aluminium biokinetics at the ultra-trace element level. With the model, the measured values of (26)Al in serum and urine were used to precisely determine absorption, speciation, distribution, retention and excretion of aluminium in humans.  相似文献   
6.
Slovick  FT; Abboud  CN; Brennan  JK; Lichtman  MA 《Blood》1985,66(5):1072-1079
The growth of human eosinophil progenitors (CFU-Eo) and the modulation of growth by hydrocortisone were studied as functions of the presence of lymphocytes and monocytes in marrow cells under study; and the source of colony-stimulating factors, specifically, media conditioned by macrophage-like cell line, GCT; phytohemagglutinin-stimulated mononuclear cells (PHA-LCM); or the T cell line, MO. CFU-Eo growth was greatest in marrow containing accessory cells as compared to marrow depleted of accessory cells; and in marrow treated with phytohemagglutinin-stimulated leukocyte conditioned media (PHA-LCM) or MO (T cell line)-conditioned medium (MO-CM) as compared with GCT cell- conditioned medium (GCT-CM). Hydrocortisone reproducibly inhibited eosinophil progenitor growth in unfractionated marrow stimulated by GCT- CM. This effect was abrogated by admixing irradiated mononuclear cells or T lymphocytes with the target marrow or by adding interleukin 1 or interleukin 2 (IL-1, IL-2). Inhibition by hydrocortisone did not occur when monocyte and T lymphocyte depleted marrow was studied. Unlike GCT- CM, MO-CM and PHA-LCM stimulated equal proportions of eosinophil progenitors in nondepleted and accessory cell-depleted marrow and demonstrated less hydrocortisone inhibition. However, both GCT-CM and PHA-LCM produced in the presence of hydrocortisone stimulated significantly fewer CFU-Eos in both unfractionated and accessory cell- depleted marrow target populations. These results indicate that the growth of CFU-Eo and inhibition of growth by hydrocortisone is a direct function of a monocyte-T cell interaction and probably is mediated through effects on the production/release of eosinophil colony stimulating factor (Eo-CSF).  相似文献   
7.
Schiffer  CA; Sanel  FT; Young  VB; Aisner  J 《Blood》1977,50(2):213-225
The effects of the cationic anesthetic agents tetracaine and lidocaine on granulocyte function, morphology, and adherence to nylon fibers were studied in an attempt to improve current methods of granulocyte collection by filtration leukapheresis (FL). When dissolved in acid- citrate-dextrose (ACD) plasma, these drugs significantly increased granulocyte elution from the fibers in a dose-related fashion. Granulocytes exposed to tetracaine and lidocaine remained more than 95% viable, retained normal bactericidal capacity after the drugs were washed from the cells, and had preserved membrane integrity, as evidenced by the normal ultrastructural appearance of tetracaine- exposed cells and an absence of leakage of lysozyme or lactic dehydrogenase. Granulocytes eluted with the anesthetic agents were rounded in shape with a reduction in the number of filopodial cytoplasmic projections and a relative absence of cytoplasmic vacuolization when compared to granulocytes eluted with ACD plasma alone. Dose-related inhibition of phagocytosis and adherence, which was largely reversible after washing the granulocytes, was noted. Greater than 95% of the lidocaine could be removed from the eluate with a single centrifugation and resuspension, indicating that granulocytes prepared by FL with anesthetic-enhanced elution could be potentially transfusable.  相似文献   
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Parkin and the glial cell line–derived neurotrophic factor (GDNF) receptor RET have both been independently linked to the dopaminergic neuron degeneration that underlies Parkinson’s disease (PD). In the present study, we demonstrate that there is genetic crosstalk between parkin and the receptor tyrosine kinase RET in two different mouse models of PD. Mice lacking both parkin and RET exhibited accelerated dopaminergic cell and axonal loss compared with parkin-deficient animals, which showed none, and RET-deficient mice, in which we found moderate degeneration. Transgenic expression of parkin protected the dopaminergic systems of aged RET-deficient mice. Downregulation of either parkin or RET in neuronal cells impaired mitochondrial function and morphology. Parkin expression restored mitochondrial function in GDNF/RET-deficient cells, while GDNF stimulation rescued mitochondrial defects in parkin-deficient cells. In both cases, improved mitochondrial function was the result of activation of the prosurvival NF-κB pathway, which was mediated by RET through the phosphoinositide-3-kinase (PI3K) pathway. Taken together, these observations indicate that parkin and the RET signaling cascade converge to control mitochondrial integrity and thereby properly maintain substantia nigra pars compacta dopaminergic neurons and their innervation in the striatum. The demonstration of crosstalk between parkin and RET highlights the interplay in the protein network that is altered in PD and suggests potential therapeutic targets and strategies to treat PD.  相似文献   
10.
The purpose of this study was to evaluate the effects of an 8-week program of hippotherapy on energy expenditure during walking; on the gait dimensions of stride length, velocity, and cadence; and on performance on the Gross Motor Function Measure (GMFM) in five children with spastic cerebral palsy (CP). A repeated-measures within-subjects design was used consisting of two baseline measurements taken 8 weeks apart, followed by an 8-week intervention period, then a posttest. After hippotherapy, all five children showed a significant decrease (Xr2;=7.6, P<0.05) in energy expenditure during walking and a significant increase (Xr2=7.6, P<0.05) in scores on Dimension E (Walking, Running, and Jumping) of the GMFM. A trend toward increased stride length and decreased cadence was observed. This study suggests that hippotherapy may improve energy expenditure during walking and gross motor function in children with CP.  相似文献   
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