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91.
Aminophylline, a bronchodilator, was considered a suitable drug for targeting to the lung to treat emphysema. Factorial concept was utilized to optimize the size and drug loading of microspheres suitable for targeting. Aminophylline-loaded albumin microspheres were prepared by heat denaturation adjusting the manufacturing variables, namely albumin concentration, drug concentration, water-oil phase ratio and stirring rate at low and high levels. For two levels of the four variables the experimentation was performed in 16 batches. A good yield of well-defined microspheres of the size range, 2-30 microns, were obtained from all the batches. The drug loading was found maximum (36.33 per cent) in batch XV of microspheres prepared with low albumin concentration, high drug concentration, low water-oil phase ratio and low stirring rate. The least number (13 per cent) of microspheres of batch XV were below 7 microns and the remaining 87 per cent were above this size. Considering the payload and size, microspheres of batch XV were found suitable for targeting to the lung. 相似文献
92.
93.
M Noguchi T Kodama Y Shimosato T Koide T Naruke G Singh S L Katyal 《The American journal of surgical pathology》1986,10(2):134-139
A case of papillary adenoma of type 2 pneumocytes is reported. A 57-year-old man had an unusual coin lesion in the periphery of the right lung without any symptoms. When detected in a mass survey examination, it was approximately 1.5 cm in diameter, well circumscribed, and located in S4, involving the sixth-order bronchus of B4. Light-microscopic examination revealed cuboidal tumor cells arranged in a papillary pattern. Ultrastructurally, the cells had characteristic osmiophilic lamellar bodies. By immunoperoxidase staining, the tumor cells were shown to have intracytoplasmic surfactant apoproteins. The postoperative course was uneventful, and there is no evidence of disease 8 years later. 相似文献
94.
The relationship between stressful family life events and somatic complaints in 477 school children was studied. There was a significant association between life events and somatic complaints, with a general trend for somatic complaints to increase in almost direct proportion to the number of family life events. Overall occurrence of these nonspecific symptoms was more in girls. The somatic complaints were significantly more in children from nuclear families and of illiterate or poorly educated mothers. No significant association was observed between somatic complaints and number of children in the family or socio-economic status. Assessment of psychodevelopmental tasks and family environment during routine check up of children by the school health teams and their appropriate training in this field should be stressed upon. 相似文献
95.
M Tandon S Singh L Xu P Kumar L I Wiebe E E Knaus W P Gati M L Tempest 《Drug design and discovery》1992,9(1):79-91
The synthesis of the two diastereomers (9 and 10) of 5-(2,2-difluorocyclopropyl)-2'-deoxyuridine are described. Their antiviral and cytotoxic activities were determined, in comparison with (E)-5-(2-bromovinyl)-2'-deoxyuridine (BVDU) and 5-fluoro-2'-deoxyuridine (FDU), respectively. 5-[(1R)-2,2-Difluorocyclopropyl]-2'-deoxyuridine (10) was the most active antiviral agent against HSV-1 (IC50 = 5 micrograms/ml) relative to BVDU (IC50 = 0.082 micrograms/ml), and cytotoxic agent in the CCRF-CEM (IC50 = 230 microM) screen relative to FDU (IC50 = 4.7 x 10(-3) microM). The 5-[(1S)-2,2-difluorocyclopropyl] diastereomer was inactive in both screens. Partition coefficients (P) and affinity for the mouse erythrocyte nucleoside transporter (Ki) were not determinants of antiviral or cytotoxic activities. However, the (1R)-diastereomer (10) was more resistant to glycosidic bond cleavage by thymidine phosphorylase than the (1S)-diastereomer (9). 相似文献
96.
Earlobe reconstruction using a Limberg flap in six ears. 总被引:2,自引:0,他引:2
Many methods of earlobe reconstruction using one or two stages have been described. These have used (i) the superimposition of two flaps, (ii) a single flap lined with a skin graft or (iii) doubled-over single or bilobed flaps. We present a new method of earlobe reconstruction using a doubled-over Limberg flap, which we have used in six ears. This produces a good-looking earlobe, which needs defatting after 3-4 months and suffered minimal necrosis at the tip of the folded flap in three cases. There was no earlobe shrinkage on long-term follow-up. 相似文献
97.
H S Watson E O Singh M R Hermans K S Coffield G T Keegan 《The Journal of urology》1992,147(3):689-691
We report a case of eosinophilic cystitis that was responsive to prednisone but that recurred when the drug was withdrawn. The cause of eosinophilic cystitis remains an enigma but it probably represents a form of allergy. Investigation of etiology and therapeutic options are discussed. 相似文献
98.
Our data suggest that DOX resistance in P388/R-84 cells may result, at least in part, from reduced free radical formation by both suppression of flavin reductase(s) and overexpression of certain antioxidant enzymes such as GSH peroxidase and catalase. In addition, our results, in conjunction with other studies, indicate that flavin reductase(s) and antioxidant enzymes are differentially altered in cancer cells with acquired or de novo resistance to DOX. Further studies are needed, however, to elucidate the mechanism(s) by which the gene expression of these enzymes is regulated in drug-sensitive and -resistant cells. 相似文献
99.
A Singh P A Deuster B A Day D J Smith J E DeBolt T J Doubt 《Undersea biomedical research》1988,15(2):135-145
The nutritional status of 16 male, land-based U.S. Navy divers was assessed to collect baseline information for a cold water dive series. Diet records, blood samples, and 24-h urine collections were obtained and analyzed. The divers were deriving 17 +/- 1%, 40 +/- 2%, 32 +/- 2% of their calories from protein, carbohydrate, and fat, respectively. The remaining calories were furnished by alcohol (11 +/- 2%), an amount within the American Heart Association's guidelines. Crude fiber intake was low (3.7 +/- 0.4 g/d) whereas cholesterol (507 +/- 101 mg/d) and sodium intakes (4462 +/- 599 mg/d) were high. Mean intakes of vitamin B6 and folacin were below the Military Recommended Dietary Allowances. Mean blood concentrations and urinary excretion of minerals were normal but urinary sodium excretion was high. Results indicate that the divers' intakes of sodium and cholesterol were high, whereas intakes of complex carbohydrate and crude fiber were low. Whether these dietary patterns are suitable for extended dives, especially in cold water, remains to be determined. 相似文献
100.
Adsorption and movement of carbofuran (a systemic nematicide) were studied using two Indian soils (clay loam and silt loam) of alluvial origin. Equilibrium adsorption coefficient (K) values measured using a batch-slurry technique follows the order clay loam greater than silt loam soil. The distribution coefficients (Kd) for both the soils in batch adsorption as well as in columns were also calculated. Carbofuran movement in soil columns during water infiltration in both air-dried and water-saturated columns was estimated. The order was as anticipated from K and Kd values. A larger amount of water was needed for leaching the carbofuran to 152 cm in clay loam soil than in silt loam soil. Carbofuran appears to increase in drier soils and in finer textured soils. 相似文献