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71.
Phytochemical and antimicrobial studies on Drynaria quercifolia   总被引:1,自引:0,他引:1  
Friedelin, epifriedelinol, beta-amyrin, beta-sitosterol, beta-sitosterol 3-beta-D-glucopyranoside, and naringin were isolated from the dried rhizome of Drynaria quercifolia. The methanol extract showed broad and concentration-dependent antibacterial activity.  相似文献   
72.
Fulzele DP  Satdive RK 《Fitoterapia》2005,76(7-8):643-648
The topoisomerase I-DNA inhibitor alkaloid camptothecin has been evaluated from the various parts of Nothapodytes foetida. The bark contained 0.27% dry wt of camptothecin and 0.11% dry wt 9-methoxycamptothecin followed by the root, stem, and leaves. Immature seeds contained higher concentrations of camptothecin (0.32% dry wt) and 9-methoxycamptothecin (0.16% dry wt) compared to mature seeds. Various parts of mature and immature seeds were analysed to determine the content of the major alkaloids. Zygotic embryos of immature seeds contained 0.11% dry wt of camptothecin and 0.04% dry wt of 9-methoxycamptothecin. The highest concentration of camptothecin (0.42% dry wt) and 9-methoxycamptothecin (0.18% dry wt) were accumulated in the cotyledons of immature seeds.  相似文献   
73.
Antihyperglycemic activity of Caralluma attenuata   总被引:1,自引:0,他引:1  
Extracts of Caralluma attenuata are screened for their antihyperglycemic activity. Ethanol, chloroform and butanol extracts were tested on glucose loaded and alloxan-induced diabetic rats. In both tests, the butanol extract, at the oral dose of 250 mg/kg, has shown statistically significant and considerable antihyperglycemic activity.  相似文献   
74.
Murthy  Ramesh  Goldfarb  Barry 《New Forests》2001,21(3):217-230
Two experiments were conducted to determine theeffect of handling, short-term storage, andinitial water stress on cutting water potential (W) and rooting of loblolly pine(Pinus taeda L.) stem cuttings. First,stock plants and cuttings were measured forW at predawn (04:00 a.m.) and earlymorning (09:00 a.m.). Cuttings were thensevered, wrapped in wet paper towels, andplaced in insulated containers for 2 or 7 h atapproximately 30 °C or for 21 h in coldstorage (4 °C). Water potentials ofcuttings were measured at the end of eachstorage period. Second, effects of initialwater stress on rooting performance of cuttingswere tested by withholding water from dormant(winter) and succulent (summer) cuttings forvarying periods of time. After each dryingtreatment, W was measured on asample of cuttings and the remainder of thecuttings were transferred to a greenhouse withintermittent mist for 12 weeks.Storage of cuttings for long periods (7 to 21h) of time under low vapor pressure deficitconditions resulted in less negative waterpotentials of the cuttings. Dormant cuttingsrooted at higher percentages, even after beingexposed to lower values of W Thelower values of W in dormantcuttings could be attributed to higher ambientvapor pressure deficit during the drying phase. Results suggest that subjecting cuttings tomoderate water stress for a short period oftime does not adversely affect the rooting ofcuttings. Cutting water potentials below –1.7MPa appeared to reduce rooting of succulentcuttings and water potentials below –2.0 MPaaffected rooting in dormant cuttings.  相似文献   
75.
76.
A study was conducted in 2008 to determine the prevalence of Anaplasma and Babesia infections in cattle in the Puntarenas Province of Costa Rica. Blood samples were taken from a total of 449 cattle during the month of March at 30 farms in the region of Espiritu Santu, Costa Rica. Commercially available enzyme-linked immunosorbent assays (ELISA) were used to determine presence of antibodies to Babesia bigemina and Anaplasma marginale, and real-time PCR was used to determine the presence of DNA from the disease-causing organisms. The ELISA results indicated that 87.5% of the cattle sampled were positive for antibodies to A. marginale, while 59.1% were positive for antibodies to B. bigemina. The real-time PCR results showed that 235 cattle were carrying A. marginale DNA (56.9%), 6 with B. bigemina DNA (1.34%), and 2 with B. bovis DNA (0.45%).  相似文献   
77.
Studies were conducted to examine the effects of the cyclicity and the presence of a dominant follicle (DF) in ovary on the recovery and in vitro growth of pre-antral follicles (PFs) in sheep and buffalo. Small pre-antral follicles (SPFs, 100–250 μm) and large pre-antral follicles (LPFs, 250–450 μm) were isolated from slaughterhouse ovaries in the breeding seasons by a mechanical and enzymatic method. The sheep and buffalo PFs were cultured in vitro for 6 and 15 days, respectively, and examined for their growth, survival and antrum formation rates and growth rates of oocytes in cultured pre-antral follicles. The follicles of the sheep and buffalo were recovered and cultured simultaneously within replicates. The recovery rates (number per ovary) of both SPFs and LPFs were significantly (p < 0.05) higher in cyclic ewes (SPFs: 22.0 ± 3.3 vs 12.1 ± 2.6 and LPFs: 16.0 ± 3.6 vs 9.2 ± 1.8) and buffaloes (SPFs: 9.2 ± 1.3 vs 4.1 ± 1.0 and LPFs: 10.3 ± 2.7 vs 5.4 ± 0.7) compared with those recovered from acyclic ones. Presence of a DF in ovary significantly (p < 0.05) reduced the recovery rates of LPFs in ewes (9.06 ± 2.7 vs 16.4 ± 3.8) but had no effect in buffalo. Cyclicity of animals or follicular dominance had no effects on in vitro growth, survival and antrum formation rates and growth rates of oocytes in cultured PFs of SPFs and LPFs in both sheep and buffalo. The in vitro growth, survival and antrum formation rates of LPFs and growth rates of oocytes in cultured LPFs were significantly (p < 0.05) higher than those observed in SPFs in both sheep and buffalo. The overall recovery and growth rates of the PFs were lower in buffaloes compared with ewes.  相似文献   
78.
Decolorization of six synthetic dyes and two raw textile effluents (A and B) by eight basidiomycetous fungi was investigated. Among eight basidiomycetous fungi, fungal isolate RCK-1 decolorized textile effluent A maximally (42%), while fungal isolate RCK-3 was found to decolorize more of Congo Red (69%), Xylidine Ponceau 2R (100%), Poly R-478 (96%), Indigo Carmine (99%), Lissamine Green B (90%), Toluidine Blue (57%) and textile effluent B (54%), than the rest of fungi. Percentage decolorization of all synthetic dyes and textile effluents by the new fungal isolates RCK-1 and RCK-3 was higher compared to the most widely studied simultaneous lignin degrader, Phanerochaete chrysosporium and selective lignin degrader, Pycnoporus cinnabarinus, when tested in liquid cultures. A statistically significant positive correlation between laccase production and decolorization of dyes and effluents was obtained as compared to other ligninolytic enzymes (lignin peroxidase and manganese peroxidase) production. This showed the importance of the differential contribution of the different ligninolytic enzymes towards the decolorization of the synthetic dyes and textile effluents. The substantially higher ligninolytic enzyme production by the fungal isolates RCK-1 and RCK-3 also suggested their potential use for textile effluent treatment and other possible biotechnological applications.  相似文献   
79.
The objective of this paper is to design a pilot plant electrochemical reactor and to prove the operational concept of the electrochemical production of ferrate in situ and its online application for sewage treatment. To that end, the first part of this paper focuses on the analysis of the main engineering aspects of the reactor and the electrochemical process that affect the ferrate production, using laboratory scale experiments such as the interelectrode gap, the space-time yield, the area/volume (A/V) ratio, the current efficiency, and the energy consumption. The second part focuses on the production of ferrate using a pilot plant scale to prove the operational concept of the electrochemical generation of ferrate in situ and its online application as a step towards its full scale application for water and wastewater treatment.  相似文献   
80.
The plasma concentrations and pharmacokinetics of the fluoroquinolone antimicrobial agent pefloxacin, following the administration of a single intravenous (10 mg/kg) or oral (20 mg/kg) dose, were investigated in healthy female goats. The antimicrobial activity in plasma was measured at predetermined times after drug administration by an agar well diffusion microbiological assay, using Escherichia coli (ATCC 25922) as the test organism. Concentrations of the drug 0.25 g/ml were maintained in plasma for up to 6 and 10 h after intravenous (IV) or oral administration of pefloxacin, respectively. The concentration–time data for pefloxacin in plasma after IV or oral administration conformed to two- and one-compartment open models, respectively. Plasma pefloxacin concentrations decreased rapidly during the initial phase after IV injection, with a distribution half-life (t 1/2 ) of 0.10±0.01 h. The terminal phase had a half-life (t 1/2 ) of 1.12±0.21 h. The volume of distribution at steady state (V dss), mean residence time (MRT) and total systemic clearance (ClB) of pefloxacin were 1.08±0.09 L/kg, 1.39±0.23 h and 821±88 (ml/h)/kg, respectively. Following oral administration of pefloxacin, the maximum concentration in the plasma (C max) was 2.22±0.48 g/ml and the interval from administration until maximum concentration (t max) was 2.3±0.7 h. The absorption half-life (t 1/2 ka), mean absorption time (MAT) and elimination half-life of pefloxacin were 0.82±0.40, 4.2±1.0 and 2.91±0.50 h, respectively. The oral bioavailability of pefloxacin was 42%±5.8%. On the basis of the pharmacokinetic data, a dosage regimen of 20 mg/kg, IV at 8 h intervals or orally twice daily, is suggested for treating infections caused by drug-sensitive pathogens in goats.  相似文献   
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