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101.
Present study was designed to examine daily and seasonal variability in the innate immune responses of splenocytes in the fresh water snake, Natrix piscator. Animals were mildly anesthetized and spleen was aseptically isolated and processed for macrophage phagocytosis, NBT reduction, nitrite production, splenocyte proliferation and serum lysozyme activity. Samples were collected at seven time points, viz., 0000, 0400, 0800, 1200, 1600, 2000 and 0000 h during three different seasons, namely summer, winter and spring. Cosinor analysis revealed that percent phagocytosis had a significant 24-h rhythm during summer and spring seasons. The peaks of rhythms in NBT reduction and nitrite release occurred in the morning hours at 10.88 h and 8.31 h, respectively, in winter. A significant 24-h rhythm was also observed in lysozyme concentration and splenocyte proliferation (both Basal and Concanavalin A stimulated) in all three seasons. A significant phase shift in splenocyte proliferation was obtained with a trend of delayed phase shift from winter to spring and from spring to summer. Of the nine variables, significant annual (seasonal) rhythms were detected in almost all variables, excluding phagocytic and splenosomatic indices. All rhythmic variables, except spleen cellularity, exhibited tightly synchronized peaks coinciding with the progressive and recrudescence phases of annual reproductive cycle. It is concluded that the snake synchronizes its daily and seasonal immune activity with the corresponding external time cues. The enhancement of immune function coinciding with one of its crucial reproductive phases might be helping it to cope with the seasonal stressors, including abundance of pathogens, which would otherwise jeopardize the successful reproduction and eventual survival of the species.  相似文献   
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103.
The present study was aimed at examining the putative thyroid or androgen dependency of the roles of melatonin/the pineal in the regulation of serum cholesterol in a freshwater catfish, Clarias batrachus . During four different phases of the annual gonadal cycle melatonin-treated or pinealectomized fishes received either iopanoic acid or cyproterone acetate or vehicle in the early morning or late afternoon. The results indicate that the effects of melatonin on serum cholesterol appear to be thyroid and testis independent during the preparatory and late postspawning phases. In contrast, the effect of pinealectomy is brought about mainly by way of the thyroid and/or the testis.  相似文献   
104.
Tannase an industrially important enzyme was produced by Aspergillus aculeatus DBF9 through a solid-state fermentation (SSF). The organism produced good amount of enzyme and gallic acid in wheat bran among the solid substrate used in SSF. Maximum enzyme and gallic acid production occurred in 5% tannic acid after 72 h. Eighty percent initial substrate moisture and 30 degrees C temperature was found suitable for tannase production.  相似文献   
105.
A series of 2-arylidene-1-indanones, 1, had been shown previously to display cytotoxic properties towards Molt 4/C8, CEM and L1210 cells. In the present study, two series of analogues of 1 were prepared namely various 2-arylidene-1,3-indandiones, 2, and chalcones, 3. In general, the potencies of compounds 2 and 3 were greater than the analogues bearing the same aryl substituents in series 1. Molecular modeling was undertaken in order to seek explanations for the variation in bioactivities.  相似文献   
106.
The International Union for Conservation of Nature (IUCN) Red List categories and criteria were applied to small-sized spore-producing plants with high dispersal capacities (bryophytes). The application of some of the IUCN criteria to bryophytes in small and highly environmental diverse islands implies several problems. The criteria applicability increases when the occupancy area is reduced. However, for common species restricted to a single type of vegetation belt, the use of the IUCN criteria is problematic because of inapplicable and/or misleading thresholds. We adapted the IUCN criteria by modifying the occupancy and occurrence area sizes and by specifying the location. This approach allowed us to establish the first Red List for the bryophyte species in the Canaries, which comprises 105 species (67 mosses and 38 liverworts); among them, 7 are critically endangered, 20 are endangered and 78 are vulnerable. Twenty-six species were classified as near-threatened, 245 were considered to be at low risk and 125 were data deficient (DD). Among the DD ones, 19 corresponded to newly reported species (DD-n) and 40 had no records during the last 30?years (DD-va). Our findings show that the freshwater habitats as well as the habitats in the most restricted cloud forests (with Erica platycodon) contain the majority of the threatened species, followed by other types of laurel forests and high mountain habitats.  相似文献   
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108.
In vitro propagation of rose--a review   总被引:1,自引:0,他引:1  
In vitro propagation of rose has played a very important role in rapid multiplication of cultivars with desirable traits and production of healthy and disease-free plants. During the last several years, different approaches have been made for in vitro propagation of rose. Micropropagation using apical buds or nodal segments and understanding the specific requirements at different stages has been comprehensively covered in literature. New challenges for refinements of protocols for high rate of shoot multiplication and development of cost effective methods has gained importance in the recent past. Importance of liquid static culture for shoot proliferation and root induction for rose is also discussed in the present review. Further, the development of protocol for in vitro plant regeneration which is considered as most important step for successful implementation of various biotechnological techniques used for plant improvement programmes has been adequately addressed in literature. In rose, there are several reports which indicate rapid regeneration and multiplication through organogenesis or somatic embryogenesis. On the whole, the present review gives a consolidated account of in vitro propagation in rose.  相似文献   
109.

Background

Leprosy was eliminated as a public health problem (<1 case per 10,000) in India by December 2005. With this target in sight the need for a separate vertical programme was diminished. The second phase of the National Leprosy Eradication Programme was therefore initiated: decentralisation of the vertical programme, integration of leprosy services into the primary health care (PHC) system and development of a surveillance system to monitor programme performance.

Methodology/Principal Findings

To study the process of integration a qualitative analysis of issues and perceptions of patients and providers, and a review of leprosy records and registers to evaluate programme performance was carried out in the state of Orissa, India. Program performance indicators such as a low mean defaulter rate of 3.83% and a low-misdiagnosis rate of 4.45% demonstrated no detrimental effect of integration on program success. PHC staff were generally found to be highly knowledgeable of diagnosis and management of leprosy cases due to frequent training and a support network of leprosy experts. However in urban hospitals district-level leprosy experts had assumed leprosy activities. The aim was to aid busy PHC staff but it also compromised their leprosy knowledge and management capacity. Inadequate monitoring of a policy of ‘new case validation,’ in which MDT was not initiated until primary diagnosis had been verified by a leprosy expert, may have led to approximately 26% of suspect cases awaiting confirmation of diagnosis 1–8 months after their initial PHC visit.

Conclusions/Significance

This study highlights the need for effective monitoring and evaluation of the integration process. Inadequate monitoring could lead to a reduction in early diagnosis, a delay in initiation of MDT and an increase in disability rates. This in turn could reverse some of the programme''s achievements. These findings may help Andhra Pradesh and other states in India to improve their integration process and may also have implications for other disease elimination programmes such as polio and guinea worm (dracunculiasis) as they move closer to their elimination goals.  相似文献   
110.
Desulfomicrobium baculatum is the type species of the genus Desulfomicrobium, which is the type genus of the family Desulfomicrobiaceae. It is of phylogenetic interest because of the isolated location of the family Desulfomicrobiaceae within the order Desulfovibrionales. D. baculatum strain X(T) is a Gram-negative, motile, sulfate-reducing bacterium isolated from water-saturated manganese carbonate ore. It is strictly anaerobic and does not require NaCl for growth, although NaCl concentrations up to 6% (w/v) are tolerated. The metabolism is respiratory or fermentative. In the presence of sulfate, pyruvate and lactate are incompletely oxidized to acetate and CO(2). Here we describe the features of this organism, together with the complete genome sequence and annotation. This is the first completed genome sequence of a member of the deltaproteobacterial family Desulfomicrobiaceae, and this 3,942,657 bp long single replicon genome with its 3494 protein-coding and 72 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project.  相似文献   
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