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81.
The green alga Botryococcus protuberans was isolated from its natural environment and its morphology under different cultural conditions was examined. The alga was characterized by a high starch content and reddish oil drops as the assimilatory products. Photosynthetic pigments, Chl a, Chl b, carotenoids and xanthophylls are present. Modification of environmental conditions in modified Chu-10 medium resulted in optimum growth of the alga. Fatty acid composition revealed palmitic acid being the major component, while lauric acid, myristic acid and stearic acid were found in less quantity.  相似文献   
82.
The paper deals with 45 species of 21 genera of fresh water blue green algae (BGA) from three different agro-climatic zones of Uttar Pradesh. Samples were collected from different habitats varying in physico-chemical properties. Out of 45 species, 13 species belonged to order Chroococcales, 31 to order Nostocales, while only 1 species belonged to order Stigonimatales i.e. Fischerella mucicola. The physico-chemical parameters like pH, temperature, dissolved oxygen, electrical conductivity, nitrate, nitrite and rainfall play an important role in the periodicity of BGA. A positive correlation was found between dissolved oxygen (DO) of different ponds and species diversity, except in the case of western region of Uttar Pradesh (Farukhabad and Mahoba districts) where a positive correlation was found in electrical conductivity and total dissolved solids.  相似文献   
83.
Arsenic (As) contamination of water and soil has become a subject of prime interest due to its direct effect on human health through drinking water and food. In present study two varieties (CSG-8962 and C-235) of chickpea, Cicer arietinum L., which is a major supplementary food in many parts of India and a valuable source of protein, has been selected to estimate the level of arsenate in root and shoot of five day old seedlings vis-à-vis effect of arsenate on seedling growth and induction of thiols including glutathione (GSH) and phytochelatins (PCs) and their homologues. Both varieties accumulated arsenate to similar levels and most of the metalloid was confined to roots, only about 2.5% was translocated to shoot. Plant growth was also not affected significantly in both the varieties. Arsenate exposure significantly induced the levels of thiols including PCs and homophytochelatins (hPCs). The induction of thiols was much higher in roots than shoots and was greater in var C-235 between the two tested ones. Thus, both varieties tolerated and detoxified arsenic through chelation with GSH, PCs and hPCs, primarily in roots, however var C-235 performed better  相似文献   
84.
Studies were conducted on population dynamics of Metaphire posthuma, Lampito mauritii and Dichogaster bolaui in cultivated pedoecosystem of desert region of Rajasthan. The populations of aclitellate and clitellate M. posthuma, L. mauritii and D. bolaui were maximum in rainy season and minimum in summer season. The abundant population of these worms were found during the months of July to October. The species M. posthuma breed throughout the year except in extreme summer but L. mauritii breed twice in a year in the field. However, D. bolaui breed once in a year. Among these earthworm species D. bolaui with relative density of 44.2% was the most dominant species in cultivated land while L. mauritii and M. posthuma contributed 33.3% and 22.5% of density, respectively. The total population of earthworms showed significant positive correlation with different soil nutrients.  相似文献   
85.
The effects of sublethal concentration of fenvalerate on DNA, RNA, RNA/DNA ratio and protein contents were estimated in gill and kidney tissues of an air breathing fish, Clarias batrachus. Fenvalerate reduced the DNA content in gill, whereas it did not produce any significant effect on DNA in kidney. This tissue-specific change in DNA content may be due to differential effects of fenvalerate or its metabolite(s) on synthesis and/degradation of DNA in gill and kidney cells of the fish. RNA and protein contents declined substantially in both the tissues in response to fenvalerate treatment. However, RNA/DNA ratio remains unchanged. It indicates that decrease in protein content in response to fenvalerate treatment might have been brought about by reduce rate of translation of messenger (mRNA) without a decrease in concentration of ribosomes.  相似文献   
86.
Ali MB  Tripathi RD  Rai UN  Pal A  Singh SP 《Chemosphere》1999,39(12):2171-2182
Lake Nainital is the sole source of drinking water for the local people and even to majority of tourists. In background of lake utility and its importance at national level, such study is essential which is focused on toxic metal pollution and current nutrient status of the lake and their magnification by algae and macrophytes. Study has shown that lake water is rich in nutrients which supports growth of many aquatic macrophytes and algal blooms. Besides, water is contaminated with metals like Cr, Cu, Fe, Mn, Ni, Pb and Zn. Concentration of some of them like Fe, Pb and Ni were higher than the recommended maximum permissible limits. Concentration of these metals were also found high in lake sediments. The level of metals amongst various components of lake varied considerably in different season. Plants and algae growing therein accumulated appreciable amount of metals and water roots of Salix being more efficient than others. High metal removing potential of these plants may be significant for biomonitoring studies and could be a useful phytoremediation technology to restore water quality by harvesting submerged and floating biomass inhabiting littoral zone of the lake.  相似文献   
87.
Vajpayee P  Tripathi RD  Rai UN  Ali MB  Singh SN 《Chemosphere》2000,41(7):1075-1082
Plants of Nymphaea alba L. grown at various levels of chromium (VI) ranging from 1 to 200 microM accumulated chromium in concentration and duration-dependent manner. At all Cr levels, chromium accumulation by various plant tissues followed the order roots > leaves > rhizomes. Approximately 93% of total chromium present in the medium was accumulated by plants at lowest conentration (1 microM) used in the experiment. Chromium-induced toxicity appears at 1 microM chromium resulting in the build-up of delta-aminolevulinic acid (ALA) and reduced activities of delta-aminolevulinic acid dehydratase (ALAD) and nitrate reductase (NR), total chlorophyll (Chl) and protein contents. Ch1a was more sensitive than Ch1b to chromium toxicity. It could be inferred that chromium toxicity is not located at the level of ALA synthesis, but, probably at the ALAD activity which was more severely affected during chlorophyll biosynthesis. Finally, impaired chlorophyll biosynthesis resulted in reduced total chlorophyll content.  相似文献   
88.
89.
In this study, Bacillus cereus isolate from tannery effluent was employed for orange II dye decolorization in simulated minimal salt broth and textile effluent. Most of the physicochemical parameters of textile effluent were above the permissible limits. The strain was highly tolerant to dye up to 500 mg l?1. Increasing dye concentration exerted inhibitory effect on the bacterial growth and decolorization. The maximum decolorization of initial 100 mg dye l?1 was achieved at optimum pH 8.0 and 33 °C under static culture conditions during 96-h incubation. Supplementation with optimized glucose (0.4 %, w/v) and ammonium sulfate (0.1 %, w/v) with 3.0 % B. cereus inoculum further enhanced dye decolorization to highest 68.5 % within 96-h incubation. A direct correlation was evident between bacterial growth and dye decolorization. Under above optimized conditions, 24.3 % decolorization of unsterilized real textile effluent by native microflora was achieved. The effluent decolorization enhanced substantially to 37.1 % with B. cereus augmentation and to 40.5 % when supplemented with glucose and ammonium sulfate without augmentation. The maximum decolorization of 52.5 % occurred when textile effluent was supplemented with optimized exogenous carbon and nitrogen sources along with B. cereus augmentation. Gas chromatography–mass spectrometry identified sulfanilic acid as orange II degradation product. Fourier transform infra red spectroscopy of metabolic products indicated the presence of amino and hydroxyl functional groups. This strain may be suitably employed for in situ decolorization of textile industrial effluent under broad environmental conditions.  相似文献   
90.

Background

Congenital cytomegalovirus (cCMV) is the most common congenital infection worldwide. cCMV can lead to severe long-term sequelae, including neurological impairment and developmental delay. We performed a systematic review of clinical practice guidelines containing recommendations concerning serological screening for CMV during pregnancy.

Method

We performed a search of MEDLINE, Turning Research into Practice (TRIP) database and the grey literature for clinical practice guidelines or consensus statements published in the English language from Jan 2010 to June 2022. The quality of the included guidelines was assessed using the Appraisal of Guidelines for Research and Evaluation (AGREE) II instrument. Textual synthesis was used to summarise and compare the recommendations on CMV serological screening in pregnancy.

Results

Eleven guidelines and two consensus statements were included. None recommended universal serological screening for CMV in pregnant women; five recommended screening for high-risk women (those with frequent contact with young children). The overall quality of the guidelines varied; most were medium or low.

Conclusions

Although clinical practice guidelines do not actively recommend routine serological screening in pregnancy, most did not meet standard processes for development and predated the emerging data on valaciclovir as a potential intervention. Existing recommendations are underpinned by limited, low-level evidence, exposing the lack of robust data in this area of practice. Further high-level evidence and methodologically robust guidelines are needed to guide clinical practice in this rapidly changing field.  相似文献   
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