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11.
Two oral liquid dosage forms of acetazolamide have been developed. Using the solubility profiles, polyethylene glycol 400 (7%, v/v) was used as the solubilizing agent and propylene glycol (53%, v/v) as the cosolvent to keep acetazolamide in solution. Because of the bitter taste of acetazolamide, sweetening agents (simple syrup, sorbitol solution, and artificial sweeteners) and flavors (raspberry, sweet, and menthol) were added to the final formulations. A buffer (either phosphate or citrate) solution was used to maintain a pH value of 4 (pH of maximum stability as reported earlier) to minimize hydrolysis. The final dosage forms were stable for at least 90 days at 37 degrees C (loss of potency of 5%). According to FDA guidelines, a tentative expiry date of 2 years at 25 degrees C is justifiable. 相似文献
12.
Levels of metals in hair of young children as an indicator of environmental pollution 总被引:1,自引:0,他引:1
In 1982 the levels of lead (Pb), cadmium (Cd), vanadium (V), copper (Cu), and selenium (Se) were determined in hair of 231 four- to five-year-old children. The objective was to explore the feasibility of using metal-in-hair levels in groups of children as an indicator of environmental pollution. The study was carried out in four areas, which were assumed to differ in ambient pollution by metals. A questionnaire on personal data, socioeconomic status, intake of beverages, and life-style was completed by the parents. The metal-in-hair levels covered a large range. The variables pertaining to location together with sex, presence of a garden, and drinking of coffee and/or tea explained 32% of the variance of Pb, 24% of the variance of Cd, and 21% of the variance of V. The total variance explained by all measured questionnaire items was at best 38%. The location was the most important factor. Cu and Se levels did not differ between the locations. 相似文献
13.
G. Biswas S. K. Ghosh S. Mukhopadhyay H. Bora 《Indian journal of otolaryngology and head and neck surgery》2002,54(3):193-195
Out of 36511 patients attending the ENT OHD of R. G,. Aur Medical Callege & Hospital. Kolkata, in one year 0.08% patients
were found tuning naspharyngeal mass. 30 cases of nasopharyngeal mass were studied. The peak incidence of nasopharyngeal mass
was in the age group between II to 20 years (40%). The incidence in males (73%) was more than females(27%). The maximum ineldence
was found among students (74%). Commonest ntuopharyngeal nuns teas antrochoanal polyp (30%). Next commlon masses were adenoids
(23%)Juvenile angwfibroma(20%) and nasophartngeal carcinoma (13%). Nasal obstruction was the main presenting symptom(83%)
followed by epistaxis (40%). 相似文献
14.
S. K. Das Chandan Kumar Ghosal B. K. Roychaudhuri P. R. Chatterjee 《Indian journal of otolaryngology and head and neck surgery》1991,43(2):80-81
Haemangioma of the maxillary sinus is rare. Clinical diagnosis is of utmost importance for its operative treatment and prevention of hazards. A case is reported for its rarity and some unusual features. 相似文献
15.
After the interaction of estrogen with the ligand binding domain (LBD) of mouse estrogen receptor‐α (mERα) and hormone‐responsive elements of target genes, many nuclear proteins are recruited to regulate the expression of specific genes. Because it is not known which brain proteins interact with LBD or whether these proteins vary with age and sex, we used pull‐down assay and far Western blotting to detect five nuclear proteins of 160, 140, 87, 60, and 46 kD in the mouse brain. These interacting proteins were identified as PELP1, RIP140, PGC1α, BAF60, and ADA3, respectively. The level of PELP1, RIP140, PGC1α, and BAF60 decreased drastically in old compared with adult male mice, whereas the ADA3 level showed no significant change. PELP1, PGC1α, and BAF60 levels were lower in old male compared with female mice. Thus we report the identification and interaction of five nuclear proteins with mERα‐LBD, indicating their role in estrogen signaling and brain functions during aging. © 2009 Wiley‐Liss, Inc. 相似文献
16.
17.
The virD operon of Agrobacterium tumefaciens Ti plasmid encodes a DNA-relaxing enzyme. 总被引:15,自引:3,他引:12 下载免费PDF全文
J Ghai A Das 《Proceedings of the National Academy of Sciences of the United States of America》1989,86(9):3109-3113
The virD locus of Agrobacterium tumefaciens Ti plasmid encodes functions necessary for endonucleolytic cleavage of transferred DNA (T-DNA) prior to its transfer to plant cells. For the overproduction of the VIRD proteins in Escherichia coli a tac-virD operon fusion was constructed. A significant increase in the accumulation of VIRD proteins was observed in a lon protease-deficient E. coli host. The presence of an overlapping open reading frame (ORF) upstream of the VIRD1 coding sequence had a negative effect on VIRD1 production. A preparation containing VIRD proteins catalyzes the conversion of supercoiled (form I) DNA to relaxed (form IV) DNA. This activity is similar to that of a DNA topoisomerase. The relaxation activity lacks DNA sequence specificity, requires magnesium ion, and has no requirement for an energy source. Studies with plasmids that had lost defined DNA segments encompassing various virD coding regions showed that VIRD1 is the DNA-relaxing enzyme. In a density gradient centrifugation experiment, the DNA-relaxing activity sedimented as a 21-kDa polypeptide. Earlier studies of Jayaswal et al. [Jayaswal, R., Veluthambi, K., Gelvin, S. & Slightom, J. (1987) (J. Bacteriol. 169, 5035-5045] have shown that in E. coli VIRD2 alone is not sufficient for endonucleolytic cleavage of T-DNA and requires VIRD1 for its activity. 相似文献
18.
Rohini Ghosh C G Nicholas Mascie-Taylor Lyliane Rosetta 《American journal of human biology》2006,18(5):630-638
A 27-month longitudinal study of 140 Bangladeshi mothers living in three tea gardens examined the effect of maternal factors (mother's age, number of live births, birth interval, and mother's work status) and sex of the infant on the duration and bout frequency of breastfeeding over 8-hr daytime periods. Prolonged breastfeeding of the infant was observed, but there was a sharp decline in duration of breastfeeding over the first 6 months, followed by a more gradual diminution thereafter. The feeding bouts showed a different pattern, with a more gradual decline over time. Housewives consistently showed a greater duration and bout frequency than women in paid employment as tea-pluckers. Over the first 6 months, primigravid mothers breastfed more frequently, but not thereafter. Older mothers (>35 years of age) breastfed with higher frequency during the first 2 months, but thereafter, the bout frequency decreased with increasing age of the infant. Over the 27-month study, maternal work status was the main factor associated with the duration and frequency of breastfeeding, with significantly higher frequency and duration among housewives. However, in the first 6 months after birth, there was very little difference in frequency or duration of breastfeeding between tea-workers and housewives, indicating that working mothers probably adjusted their time to breastfeed their infants before going, or after coming back, from work. 相似文献
19.
R. Das Gupta P. P. Chakravorty A. Kaviraj 《Bulletin of environmental contamination and toxicology》2010,85(1):83-86
The 96 h LC50 values of six insecticides were determined on a non-target epigeic earthworm Perionyx excavatus under laboratory conditions. Cypermethrin was found most toxic to P. excavatus (LC50-0.008 mg/kg), followed by endosulfan (LC50-0.03 mg/kg), carbaryl (LC50-6.07 mg/kg), chlorpyrifos (LC50-7.3 mg/kg), aldicarb (LC50-10.63 mg/kg) and monocrotophos (LC50-13.04 mg/kg). When these LC50 values were compared with their respective recommended agricultural doses, aldicarb and carbaryl appeared more dangerous
than other pesticides because of their lower LC50 values than their respective recommended agricultural dose. Mean lethal time to cause 50% mortality at recommended agricultural
dose (LT50) also indicated that aldicarb achieved the fastest LT50 (26 h) followed by endosulfan (38 h) and carbaryl (44 h) indicating the danger of these pesticides to P. excavatus. 相似文献
20.