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991.
In the present study, isolation of Moraxella bovis was done from the microbiological examination of frozen semen straws from clinically healthy twelve Jersey and one Jersey-cross bull supplied by a semen laboratory. The organism was identified on the basis of colonial morphology and biochemical characteristics. Further, viable cell count of the bacterium was studied in detail in the semen sample.  相似文献   
992.
We describe, for the first time, hydrogel-forming microneedle arrays prepared from “super swelling” polymeric compositions. We produced a microneedle formulation with enhanced swelling capabilities from aqueous blends containing 20% w/w Gantrez S-97, 7.5% w/w PEG 10,000 and 3% w/w Na2CO3 and utilised a drug reservoir of a lyophilised wafer-like design. These microneedle-lyophilised wafer compositions were robust and effectively penetrated skin, swelling extensively, but being removed intact. In in vitro delivery experiments across excised neonatal porcine skin, approximately 44 mg of the model high dose small molecule drug ibuprofen sodium was delivered in 24 h, equating to 37% of the loading in the lyophilised reservoir. The super swelling microneedles delivered approximately 1.24 mg of the model protein ovalbumin over 24 h, equivalent to a delivery efficiency of approximately 49%. The integrated microneedle-lyophilised wafer delivery system produced a progressive increase in plasma concentrations of ibuprofen sodium in rats over 6 h, with a maximal concentration of approximately 179 µg/ml achieved in this time. The plasma concentration had fallen to 71±6.7 µg/ml by 24 h. Ovalbumin levels peaked in rat plasma after only 1 hour at 42.36±17.01 ng/ml. Ovalbumin plasma levels then remained almost constant up to 6 h, dropping somewhat at 24 h, when 23.61±4.84 ng/ml was detected. This work represents a significant advancement on conventional microneedle systems, which are presently only suitable for bolus delivery of very potent drugs and vaccines. Once fully developed, such technology may greatly expand the range of drugs that can be delivered transdermally, to the benefit of patients and industry. Accordingly, we are currently progressing towards clinical evaluations with a range of candidate molecules.  相似文献   
993.
994.
Persistent hyperglycaemia and scopolamine were used to inflict amnesia in rats. Chronic hyperglycaemia causes metabolic impairment, neuronal dysfunction and oxidative stress causing cognitive impairment. This study aimed to determine anti amnesic activities of vitamin D, epalrestat and their combination against diabetes and scopolamine induced cognitive dysfunction. A total of eighty-eight Wistar albino rats, eleven groups, and 8 rats/Gr., were used. Type 2 diabetes mellitus was induced in all groups, except Gr.1 which was treated with 2 ml normal saline. Gr. 2 to 11 by feeding high fat diet for 28 days followed by single dose streptozotocin 35 mg/kg i.p. Hyperglycemic rats were screened with blood sugar level > 200 mg/dL. Gr. 2 rats were treated with only streptozotocin and Gr. 3 to 6 were treated with streptozotocin and test drugs donepezil 1 mg/kg, vitamin D, 27 mcg/kg, epalrestat 57 mg/kg, vitamin D + epalrestat, per oral, respectively. Gr. 7 rats were treated with only streptozotocin + scopolamine and all others from Gr. 8 to 11 were treated with streptozotocin + scopolamine and donepezil, vitamin D, epalrestat, vitamin D + epalrestat respectively. The gold standard behavioural tests were conducted by using Morris water maze and passive avoidance paradigms after 30–60 min of inj. scopolamine, 0.5 mg/kg, intra-peritoneal. Hippocampal tissue was taken for histopathological and biochemical evaluation. Rats treated with donepezil, vitamin D, epalrestat and vitamin D + epalrestat showed significant improvement in behavioural, biochemical and histopathological parameters as compared to streptozotocin and (streptozotocin + scopolamine) treated rats. This study underscores cognition enhancing abilities of vitamin D and epalrestat, and their combination in diabetic rats with and without scopolamine.  相似文献   
995.
IntroductionRelapse of leprosy among patients released from treatment (RFT) is an indicator of the success of anti-leprosy treatment. Due to inadequate follow-up, relapse in leprosy patients after RFT is not systematically documented in India. Relapsed leprosy patients pose a risk in the transmission of leprosy bacilli. We determined the incidence of relapse and deformity among the patients RFT from the leprosy control programme in four districts in South India.MethodsWe conducted two follow-up surveys in 2012 and 2014 among the leprosy patients RFT between 2005 and 2010. We assessed them for any symptoms or signs of relapse, persistence and deformity. We collected slit skin samples (SSS) for smear examination. We calculated overall incidence of relapse and deformity per 1000 person-years (PY) with 95% confidence intervals (CI) and cumulative risk of relapse.ResultsOverall, we identified 69 relapse events, 58 and 11, during the first and second follow-up surveys, respectively. The incidence of relapse was 5.42 per 1000 PY, which declined over the years after RFT. The cumulative risk of relapse was 2.24%. The rate of deformity among the relapsed patients was 30.9%. The overall incidence of deformity was 1.65 per 1000 person years. The duration of M. leprae detection in smears ranged between 2.38 and 7.67 years.ConclusionsLow relapse and deformity rates in leprosy RFT patients are indicative of treatment effectiveness. However, a higher proportion of detection of deformity among relapsed cases is a cause for concern. Periodic follow-up of RFT patients for up to 3 years to detect relapses early and ensure appropriate treatment will minimize the development of deformity among relapsed patients.  相似文献   
996.
997.
Measuring cell concentration is of fundamental importance in many biochemical processes. However, this measurement is very difficult to make when solid particles are present along with the cells. This review examines strategies that have been used to estimate cell concentration in the presence of solid particles.  相似文献   
998.
Callus cultures derived from internodal segments of two cultivars of carnation susceptible to Fusarium oxysporum f.sp. dianthi were successfully used for in vitro selection for resistance to this pathogenic fungus. Resistant lines were selected by culturing calli on growth medium containing various concentrations of the culture filtrate of F. oxysporum f.sp. dianthi. Resistant calli obtained after two cycles (25 days/cycle) of selection were used for plant regeneration. About 32% of the plants regenerated from the resistant calli had acquired considerable resistance against the pathogen in the field. No phenotypic variation was observed in the selected regenerates.  相似文献   
999.
The thermophilic bacterium Alcaligenes faecalis isolated from the crude oil contaminated soil of Upper Assam, India. The isolated bacterium was first screened for the ability to produce biosurfactant. The strain growing at 42 °C could produce higher amount of biosurfactant in medium supplemented with 2% (v/v) diesel as sole source of carbon and energy. Biochemical characterizations including FT-IR and MS studies suggested the biosurfactant to be glycolipid. Tensiometric studies revealed that the biosurfactant produced by the bacterial strain could decrease the surface tension (??) at air-water interface from 71.6 to 32.3 mNm−1 after 96 h of growth on hydrocarbon and possessed a low critical micelle concentration (CMC) value of approximately 38 mgl−1, indicating high surface activity. The culture supernatant containing the biosurfactant was found to be functionally stable at varying pH (2-12), temperature (100 and 121 °C) and salinity (1-6% NaCl, w/v) conditions. Both the culture broth and the cell free supernatant exhibited high emulsifying activity against the different hydrocarbons and the crude oil components. The increase in cell surface hydrophobicity and glycolipid production by the strain suggested the existence of biosurfactant enhanced interfacial uptake of the hydrocarbons. Moreover, the partially purified biosurfactant exhibited antimicrobial activity by inhibiting the growth of several bacterial and fungal species. The strain represented a new class of biosurfactant producers and could be a potential candidate for the production of glycolipid biosurfactant which could be useful in a variety of biotechnological and industrial processes, particularly in the oil industry.  相似文献   
1000.
Identification of the diverse sources of resistance is an important issue among the breeders for developing pest and disease free hybrids, to reduce the inoculum load, to prolong the life of inbred lines/hybrids and to reduce the cost of cultivation. Molecular diversity analysis was carried out among 23 maize inbred lines with respect to post flowering stalk rot and pink borer. Forty six SSR markers were employed among eight post flowering stalk rot (PFSR) and seven pink borer resistant lines along with eight other inbred lines to identify diverse resistant sources for developing resistant heterotic combinations to above pests and diseases. Number of alleles per SSR marker ranged from 2 to 9 averaging 4.11. The polymorphism information content (PIC) ranged from 0.272 to 0.839 with an average of 0.568. Discrimination rate (DR) of the markers ranged from 0.095 to 0.861 with a mean of 0.618. Number of alleles was highly correlated with PIC and DR. The pair-wise genetic dissimilarity values ranged from 0.05 to 0.84 with an overall mean of 0.64. Un-weighted neighbour joining clustering put 23 genotypes in two main clusters, which were further subdivided into 5 and 6 sub-clusters, respectively. We obtained 56 rare and 26 unique alleles in specific inbred lines, which can be used for identification of these lines. The present study has revealed considerable diversity among inbred lines differing for resistance against PFSR and pink borer; and provided ample scope for selection of parents for utilization in heterosis breeding  相似文献   
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