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991.
El Sebaie OD Hussin AH Shalaby EE Mohamed MG Lbrahem MT 《The Journal of the Egyptian Public Health Association》2000,75(1-2):131-152
Fertile soil is the most important resource for food production. The agricultural area in Egypt is limited to 6 million faddans. This limited area has derived many farmers to use several types of chemical fertilizers, to enhance the fertility of the land and hence the productivity. Excessive application of chemical fertilizer lead to the build up of these residuals because they are superfluous. This will cause waste of money and also soil pollution. Ultimately, this would adversely affect the ecological system in the soil and surrounding environment, especially water bodies. Composting of organic solid wastes will address some of the problems of solid waste disposal and gives a beneficial product which may replace the expensive chemical fertilizers. Other organic compostable solid wastes could be utilized to produce this compost. Agricultural residues are cheap raw materials for such compost and are available in vast quantities as well. This compost can be used as a soil conditioner to improve soil characteristics and its productivity. Crop residues mixed with manure, may be co-composted to give a soil conditioner. Agricultural residues, about 106 million tons/year, may produce about 55 million tons/year of compost. Three co-composting were carried out at the experimental station of the Faculty of Agriculture in Abis. Two aerobic co-composting of winter and summer crop residues and one anaerobic co-composting inter rop esidue were produced. The development of the co-composting processes controlled by the temperature, moisture content, and chemical composition was studied. The aerobic co-composting of winter crop residues was found to be the best experiment as it complied with the standards of the Ministry of Agriculture Decree No. 100/1967. This co-compost is expected to be free from pathogenic microorganisms as the dominant temperature was almost about 50 degrees C from the 42nd day till the 101st day of the experiment. 相似文献
992.
Nader A. Morad MD PhD FCAP Mourad M. El-Said MD MRCOG 《The Australian & New Zealand journal of obstetrics & gynaecology》1993,33(2):211-213
Summary: This report describes only the third case of vaginal bleeding due to uterine myoma in a patient younger than 16 years of age with unusual histological features mimicking endolymphatic stromal myosis. 相似文献
993.
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995.
Pneumopericardium: a rare cause of cardiac tamponade in an infant on a positive pressure ventilation
Cardiac tamponade most commonly results from accumulation of blood, or other fluids, within the pericardial sac. However, rarely air tamponade can lead to tension pneumopericardium and death. Positive pressure ventilation in infants carries a risk of barotrauma and presents as pneumothorax, pneumomediastinum or rarely pneumopericardium. We present an infant with cardiac tamponade due to pneumopericardium to illustrate the classical signs and symptoms, and the management of this rare condition. 相似文献
996.
Abou El Hassan MA Touw DJ Wilhelm AJ Bast A van der Vijgh WJ 《International journal of pharmaceutics》2000,211(1-2):51-56
MonoHER is a semisynthetic flavonoid used successfully in modulating the cardiotoxic effect of doxorubicin but not its antitumor activity. The oral bioavailability of monoHER is <1%. Therefore, it should be prepared as an i.v. formulation for use in clinical trials. The solubility of monoHER in water is highly pH dependent. At pH=8.3 the drug precipitates 4 h after preparation. DMSO was tested for enhancing the solubility of monoHER in aqueous solutions. In all DMSO-based aqueous solutions monoHER recrystalized again at pH<8.3 and room temperature within 4 h after preparation. Moreover, the stability of monoHER was lower in a DMSO stock solution than after dilution with an aqueous solution. The stability of monoHER was tested in alkaline solutions (pH 8.3 and 9.5) using an HPLC-DAD procedure to detect all possible degradation products within 10 min after injection. Minor degradation occurred to monoHER in alkaline solutions when exposed to daylight or 1% H(2)O(2). MonoHER intensively degraded when exposed to a high temperature (80 degrees C). The stability of monoHER was almost the same in saline or 5% glucose when kept at room temperature and an alkaline pH of 8.3 and 9.5. Under shelf-life conditions the stability of monoHER in 5% glucose (pH 8.4), decreased with about 10% during 48 h after preparation. 相似文献
997.
Oestradiol skin delivery from ultradeformable liposomes: refinement of surfactant concentration 总被引:8,自引:0,他引:8
The aims of this study were to refine ultradeformable liposomes for oestradiol skin delivery and to evaluate Span 80 and Tween 80 as edge activators compared with sodium cholate. Vesicles containing phosphatidylcholine (PC) mixed with edge activators and oestradiol were prepared. Entrapment efficiency and vesicle size were determined. Interactions between activators and vesicles were investigated using differential scanning calorimetry. Transepidermal permeation of oestradiol from vesicles was studied compared to saturated aqueous control in vitro. The maximum flux (J(max)) and its time (T(max)) were calculated from the flux curves and skin deposition was assessed. The compositions of refined formulations were predicted, liposomes prepared, and tested against control. Entrapment efficiency depended on PC concentration with some contribution from sodium cholate and Tween 80. Vesicle sizes ranged from 124 to 135 nm. Edge activators interacted with lipid bilayers and disrupted packing. The refined edge activator concentrations in PC vesicles were 14.0, 13.3 and 15.5% w/w for sodium cholate, Span 80 and Tween 80, respectively; they increased J(max) by 18, 16 and 15-fold and skin deposition by 8, 7 and 8-fold compared with control. Ultradeformable vesicles thus improved skin delivery of oestradiol compared to control and Span 80 and Tween 80 were equivalent to sodium cholate as edge-activators. 相似文献
998.
Indirect determination of captopril by AAS 总被引:2,自引:0,他引:2
El Reis MA Abou Attia FM Kenawy IM 《Journal of pharmaceutical and biomedical analysis》2000,23(2-3):249-254
An indirect method is described for the determination of captopril (KPL) in pharmaceutical preparations by atomic absorption spectrometry (AAS). The procedure is based on the complexation of KPL with an excess of Pd(II) ion. The unreacted Pd(II) was resoluted on a cationic ion-exchanger resin, while Pd(II)-KPL sequestrate was not retained. The effluent Pd(II) sequestrade was measured by AAS. The absorbance is found to increase linearly with increasing KPL concentration, because the amount of Pd(II) is related to the concentration of KPL, which is corroborate by the calculated correlation coefficient value of 0.9939. The system obeys Beer's law for 1-40 microg ml(-1), S.D. was found to be 0.039 (n = 5). The Pd(II)-KPL complex was obtained in the solid phase. Characterization of the complex was performed by elemental analysis, TG, conductance measurements and IR, 1H-NMR spectroscopy. 相似文献
999.
This study, an analysis of variable prognostic factors affecting the treatment outcome for patients with oligodendroglioma, included a retrospective analysis of the medical charts of patients diagnosed with oligodendroglioma treated at our institution between 1975 and 1997. The endpoints analyzed were the progression-free survival (PFS), as well as the overall survival. The factors analyzed included extent of surgery, postoperative radiotherapy, pathologic grade, performance status, age, and sex. Of a total of 37 cases, 19 were male and 18 were female. The median age at diagnosis was 30 years. The most common presenting symptoms were headache (78%), seizures (43%), motor symptoms (38%), and to a lesser extent behavioral changes (16%). The median duration of symptoms was 9 months. The most common location on computed tomography or magnetic resonance imaging scans was the frontal region (43%). Low grade tumors (grades I and II) were found in 60% of patients, and the remaining 40% had high grade tumors (grades III and IV). Eight patients had complete surgical excision, whereas 27 patients had partial excision, and two patients had biopsy only. The operative mortality rate was 14%. There were 24 patients who received postoperative radiotherapy, and only 3 patients received adjuvant chemotherapy. The median postoperative radiation dose was 5,580 cGy. With a median follow-up of 7 years, the 5-year PFS and overall survival for the whole group were 58% and 67%, respectively. The pathologic grade of the tumor was the only prognostic factor significantly affecting both PFS and overall survival. The 5-year PFS for patients with low grade tumors was 79% in comparison to 32% for patients with high grade tumors (p < 0.01). Patients with good performance status at initial presentation (performance status of 1 and 2) had a higher 5-year PFS in comparison to those with poor performance status (62% vs. 38%, respectively); however, this difference did not reach statistical significance. Similarly, patients who were subjected to complete surgical excision had a marginally higher PFS in comparison to those who had biopsy or partial excision (75% vs. 53%). There was no difference in the 5-year PFS between patients who received postoperative irradiation versus those who did not (51% vs. 47%, respectively). Patients with high grade oligodendrogliomas have a relatively poor prognosis. The pathologic grade of the tumor was the single most important prognostic factor significantly affecting both the PFS and overall survival. A prospective randomized clinical trial is needed to address the impact of postoperative irradiation on PFS of those tumors. In view of the poor outcome for patients with high grade oligodendroglioma, the use of adjuvant systemic chemotherapy should be studied in future multicenter randomized trials. 相似文献
1000.