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431.
Aquillochin, isolated from the whole plant of Aquilaria agallocha, has been shown to be a coumarinolignan, and a structure has been proposed on the basis of chemical and physical studies.  相似文献   
432.
Abstract

A comprehensive study was conducted from a semi-arid part of Yavtmal District, Maharashtra, India through combination approaches of geochemical modeling and its health consequences. The groundwater quality assessment shows that 55% of groundwater samples have the concentration of fluoride above the desirable limit. The high Na+/Ca+ ratio (>1.0) suggest the occurrence of cation exchange, which is further supported by Scholler’ chloro-alkaline indices. The geochemical modeling reveals that the existence of CaCO3 precipitation and CaF2 in groundwater. Simulation analysis indicates the dissolution of calcite, gypsum, and albite and precipitation of dolomite, fluorite, halite, and K-feldspar along with cation exchange as the main water–rock interactions influencing the groundwater chemistry. This is further significantly supported by pollution index of groundwater (PIG). PIG indicates about 18% of total samples fall in very high pollution zone, 3% in high pollution zone, 8% in moderate pollution zone, 24% in low pollution zone, and remaining (47%) express insignificant pollution. The 28% of subject studied have skeletal fluorosis varying from mild to severe type. In different pollution zones, the affected persons by dental fluorosis are varying from 15% to 41%. A proper monitoring and treatment are required for high fluoride water before its use for drinking and cooking.  相似文献   
433.
Area postrema is rich in angiotensin II receptors and intravenous (iv) administration of angiotensin II has been reported to elicit emesis. However, in the present study intracerebroventricular (icv) administration of angiotensin II up to a dose of 10 micrograms failed to elicit emesis. It is suggested that presence of a cerebrospinal fluid-brain barrier in area postrema most probably prevents access of icv angiotensin II to its receptors which are otherwise accessible on iv administration.  相似文献   
434.
Ten strains ofRhizobium sp. with multiple antibiotic resistance markers were used for competitive and ef ficiency studies with mung bean var. ML 5. All the strains showed significant increase in grain yield and so also for nitrogenase activity except MO 5. Nitrogenase activity correlated very well with grain yeild. The compatibility of strains varied from 17 to 50%. The intrinsic multiple antibiotic markers for strain identification were found to be stable after passing through soil and host conditions and could be used for ecological studies. It was further revealed that the overall efficiency of a strain is the combined effect of characters like compatability, competitiveness and inherent capacity to fix nitrogen.  相似文献   
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Vocal fold (VF) activity in sustained phonation captured through simultaneous visual observations via direct method (high speed digital imaging: HSDI) and via indirect electroglottographic (EGG) method in normal population were submitted to contrastive analysis. The quantitative parameters used to describe the dynamic properties of the VF vibration included open/closed quotients, and indices that we defined as harmonic ratios. Our analysis also included a Nyquist plot approach that we introduced previously. Results indicate that EGG tracings delivered useful results for the analysis of normal voices and derived a reasonably accurate open quotient value in comparison to the visual analysis. Moreover, recognizable Nyquist plot patterns were obtained for EGG tracings although not identical to that obtained from the HSDI-derived glottal area waveform. Therefore ipso-facto we evaluate the usefulness of EGG compared to visual data in describing specific voice characteristics of normal speakers.  相似文献   
437.
The retrogradely perfused medial plantar artery flap was used in a leprosy patient with a plantar ulcer over the heads of the second and third metatarsals. The flap is based on the anastomosis of the medial plantar artery with the branch of the first plantar metatarsal artery, which supplies the medial side of the great toe. This design provides reconstruction with like local tissues while not distorting the weight-bearing pattern of the foot.  相似文献   
438.
The biological mechanisms that link the development of depression to metabolic disorders such as obesity and diabetes remain ambiguous. In the present study the potential of a selective cyclooxygenase inhibitor celecoxib (15 mg/kg p.o.) was investigated in depression associated with obesity in mice. Behavioral tests used to assess depressive-like behavior were sucrose preference test, forced swim test (FST), tail suspension test (TST) and elevated plus maze (EPM). The basal locomotor score in obese mice was not altered. Furthermore, estimation of biochemical parameters was performed for plasma glucose, total cholesterol, triglycerides and total proteins. Escitalopram (10 mg/kg p.o.) served as reference standard drug. In the results, chronic treatment with celecoxib for 28 days significantly attenuated the behavioral alterations as indicated by increased the sucrose consumption, reduced the immobility time in FST and TST, increased the percent open arm time and entries in EPM in obese mice. In the biochemical parameters celecoxib significantly reversed the increased plasma glucose, total cholesterol, triglycerides and total proteins in obese mice. In conclusion, celecoxib exhibited potential antidepressant-like effect in depression associated with obesity, which to some extent is mediated by reversing the altered plasma glucose in obese mice.  相似文献   
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