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61.
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The Brunei–Indonesia–Malaysia–Philippines East Asia Growth Area (BIMP-EAGA) is located within the Coral Triangle, known to have the world’s richest biodiversity in marine flora and fauna. This region lies within the 10° N and 10° S of the Equator where natural populations of both Kappaphycus and Eucheuma grow luxuriantly and abundantly. It is in this same region where commercial cultivation of Kappaphycus and Eucheuma began in the Philippines around the mid-1960s. Commercial farming of Kappaphycus (which was originally called Eucheuma) was successful in the Philippines from the early 1970s, after which the technology was transferred to Indonesia and Malaysia in the late 1970s. No seaweed cultivation has been reported in Brunei. At present, carrageenophytes are cultivated in sub-tropical to tropical countries circumferentially around the globe within the 10° N and S of the Equator. However, their combined production is still low as compared to Indonesia, the Philippines, and Malaysia. Notably, few improvements in farming techniques have been made since its first introduction. Some of the major improvements were the introduction of deep-water farming using hanging long lines, multiple rafts, and spider webs in the Philippines; the use of short and long ‘loops’, instead of plastic ‘tie-tie’ in Indonesia; and mechanization in harvesting and use of solar “greenhouse” drying in Malaysia. Commercial cultivation of tropical red seaweeds in the BIMP-EAGA region is dominated by Kappaphycus and Eucheuma (carrageenophytes) and Gracilaria (agarophytes) and the area became the major region for the production of carageenophytes and agarophytes globally. In particular, Indonesia is a major center for the production of Gracilaria. There is an increasing demand for other agarophytes/carrageenophytes in the international market such as Gelidium spp., Pterocladia spp., Porphyroglossum sp., and Ptilophora sp. for paper and ethanol production in Indonesia and Malaysia, and Halymenia for phycoerythrin pigments in the Philippines currently pursued in an experimental stage. A summary of the present status, problems, sustainability, and challenges for the cultivation of tropical red seaweeds in the BIMP-EAGA region are discussed in this paper.  相似文献   
63.
Telocytes (Tcs) are cells with telopodes (Tps), which are very long cellular extensions with alternating thin segments (podomers) and dilated bead‐like thick regions known as podoms. Tcs are a distinct category of interstitial cells and have been identified in many mammalian organs including heart, lung and kidney. The present study investigates the existence, ultrastructure, distribution and contacts of Tcs with surrounding cells in the uterus (shell gland) of the oviduct of the Chinese soft‐shelled turtle, Pelodiscus sinensis. Samples from the uterine segment of the oviduct were examined by transmission electron microscopy. Tcs were mainly located in the lamina propria beneath the simple columnar epithelium of the uterus and were situated close to nerve endings, capillaries, collagen fibres and secretory glands. The complete morphology of Tcs and Tps was clearly observed and our data confirmed the existence of Tcs in the uterus of the Chinese soft‐shelled turtle Pelodiscus sinensis. Our results suggest these cells contribute to the function of the secretory glands and contraction of the uterus.  相似文献   
64.
This article puts forward the hypothesis that the Low Density Lipid Receptor (LDLR) is one of the molecules that is involved in the clearance of amyloid proteins in the brain and that it may play a role in Alzheimer’s Disease (AD) via its up-regulation by statins. The hypothesis is built on the following observations: a-statins (which have been shown to increase LDLR in astrocytes, see below) have a beneficial role in AD, b-defects in the LDL receptor gene are found in AD, c-molecules with similar structure to the LDLR have been shown to clear amyloid protein from the brain.  相似文献   
65.
The voltage-gated Kv2.1 channel is composed of four identical subunits folded around the central pore and does not inactivate appreciably during short depolarizing pulses. To study voltage-induced relative molecular rearrangements of the channel, Kv2.1 subunits were genetically fused with enhanced cyan fluorescent protein and/or enhanced yellow fluorescent protein, expressed in COS1 cells, and investigated using fluorescence resonance energy transfer (FRET) microscopy combined with patch clamp. Fusion of fluorophores to either or both termini of the Kv2.1 monomer did not significantly affect the gating properties of the channel. FRET between the N- and C-terminal tags fused to the same or different Kv2.1 monomers decreased upon activation of the channel by depolarization from -80 to +60 mV, suggesting voltage-gated relative rearrangement between the termini. Because FRET between the Kv2.1 N- or C-terminal tags and the membrane-trapped EYFP(N)-PH pleckstrin homology domains did not change on depolarization, voltage-gated relative movements between the Kv2.1 termini occurred in a plane parallel to the plasma membrane, within a distance of 1-10 nm. FRET between the N-terminal tags did not change upon depolarization, indicating that the N termini do not rearrange relative to each other, but they could either move cooperatively with the Kv2.1 tetramer or not move at all. No FRET was detected between the C-terminal tags. Assuming their randomized orientation in the symmetrically arranged Kv2.1 subunits, C termini may move outwards in order to produce relative rearrangements between N and C termini upon depolarization.  相似文献   
66.
Advances in tuberculosis vaccine strategies   总被引:9,自引:0,他引:9  
Tuberculosis (TB), an ancient human scourge, is a growing health problem in the developing world. Approximately two million deaths each year are caused by TB, which is the leading cause of death in HIV-infected individuals. Clearly, an improved TB vaccine is desperately needed. Heterologous prime-boost regimens probably represent the best hope for an improved vaccine regimen to prevent TB. This first generation of new vaccines might also complement drug treatment regimens and be effective against reactivation of TB from the latent state, which would significantly enhance their usefulness.  相似文献   
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The beneficial effects of plant growth promoting fungi (PGPF) on plant growth and development are well documented. However, limited information is available on gibberellin (GA) production capacity of PGPF of endophytic origin. In current study, 11 fungal endophytes were isolated from cucumber roots and then screened on Waito-C rice, in order to identify plant growth promoting fungal strains. The fungal isolate GAH7 provided the maximum shoot length (11.3 cm) in comparison to control treatment (7.8 cm). In a separate experiment, bioassay of GAH7 significantly promoted growth attributes of cucumber. The GAH7 culture filtrate (CF) was found to contain physiologically active gibberellins in higher concentrations (GA1, 0.81 ng/ml; GA3, 4.34 ng/ml and GA4, 9.31 ng/ml) in conjunction with physiologically inactive GA9 (0.74 ng/ml), GA15 (0.97 ng/ml), GA19 (1.67 ng/ml) and GA20 (0.46 ng/ml). Isolate GAH7 produced higher amounts of GA3, GA4, GA9 and GA19 than wild type Fusarium fujikuroi, which was used as control for GA production. Gibberellins were analyzed through gas chromatograph/mass spectrometer (GC/MS) with selected ion monitoring (SIM). The fungal isolate GAH7 was later identified as a new strain of Phoma on the basis of sequence homology (99%) and phylogenetic analysis of 18S rDNA sequence.  相似文献   
69.
To assess comparative losses of Trianthema portulacastrum (HP) relative to other weeds, the experiment was set during consecutive summer seasons 2018 and 2019 at the Research Farm MNS-University of Agriculture, Multan, Pakistan. Experiment consisted three replications which were laid out under randomized complete block design. Experiment consisted of ten treatments viz: weeds free (whole season), HP free till 20 Days after emergence (DAE), HP free till 40 DAE, HP free till 60 DAE, all weeds free 20 DAE, all weeds free 40 DAE, all weeds free 60 DAE, weedy check (all weeds), weedy check except HP and weedy check containing only HP. During 2018 in all weeds weedy check, maximum HP relative density (33.33%) was observed while in 2019, plot where weeds were controlled from growing till 20 DAE showed (80%) relative density at 30 DAE. HP maximum frequency (66.67%, 77.78%) and relative frequency (66%, 100%) was recorded at 45 DAE in plots where HP was kept controlled till 20 DAE and all weeds kept controlled till 20 DAE, respectively. Maximum number of grains per cob (738, 700.68), 1000 grain weight (306.66, 271.51 g) and grain yield (6150, 8015 kg hec-1) were recorded in plots which were kept all weed free till 60 DAE. As the competition period of weeds increased over 40 DAE, it substantially reduced yield of maize. Keeping the plots HP free till 40 DAE in the maize fields with HP as the major dominating weed, likely increase in maize grain yield is up to 30% compared to the fields where HP left un attended throughout the growing season. However, if maize field is infested with a mix of weeds with more than one dominating weeds including HP, compared to weedy situation the whole season, 30% higher grain yield can be obtained if all weeds are kept controlled till 40 DAE. Hence it can be concluded that whether the farmers face heavy HP infestation only or the mix of weeds as dominating weeds, in either case farmer should control weeds within first 40 days in maize field for better grain yield.  相似文献   
70.
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