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141.
Diarrhoea is a common gastrointestinal disorder which is a state of fluid and ion loss from the gut. Cauvery-100, an Ayurvedic formulation has been used in this study for the treatment of diarrhoea. Diarrhoea was induced in experimental rats by oral administration of castor oil. The increased gastrointestinal motility in diarrhoea was brought back to near normal levels on the treatment of Cauvery-100. The activities of the enzymes alkaline phosphatase, total ATPase and Na+,K(+)-ATPase were decreased in the diarrhoeal group and was brought back to near normal levels in the treated group. The serum levels of sodium and potassium were decreased in the diarrhoeal group and brought back to normal levels in the treated group. Prior treatment of the drug Cauvery-100 did not induce diarrhoea on administration of castor oil, suggesting the protective influence of the drug on the gastrointestinal tract.  相似文献   
142.
Here we introduce diffusion molecular retention (DMR) tumor targeting, a technique that employs PEG-fluorochrome shielded probes that, after a peritumoral (PT) injection, undergo slow vascular uptake and extensive interstitial diffusion, with tumor retention only through integrin molecular recognition. To demonstrate DMR, RGD (integrin binding) and RAD (control) probes were synthesized bearing DOTA (for 111 In3+), a NIR fluorochrome, and 5 kDa PEG that endows probes with a protein-like volume of 25 kDa and decreases non-specific interactions. With a GFP-BT-20 breast carcinoma model, tumor targeting by the DMR or IV methods was assessed by surface fluorescence, biodistribution of [111In] RGD and [111In] RAD probes, and whole animal SPECT. After a PT injection, both probes rapidly diffused through the normal and tumor interstitium, with retention of the RGD probe due to integrin interactions. With PT injection and the [111In] RGD probe, SPECT indicated a highly tumor specific uptake at 24 h post injection, with 352%ID/g tumor obtained by DMR (vs 4.14%ID/g by IV). The high efficiency molecular targeting of DMR employed low probe doses (e.g. 25 ng as RGD peptide), which minimizes toxicity risks and facilitates clinical translation. DMR applications include the delivery of fluorochromes for intraoperative tumor margin delineation, the delivery of radioisotopes (e.g. toxic, short range alpha emitters) for radiotherapy, or the delivery of photosensitizers to tumors accessible to light.  相似文献   
143.
144.
This report describes three cases of infant adoption in red howler monkeys (Alouatta seniculus) of Venezuela. In one case, a lactating female adopted her infant granddaughter after the infant's mother disappeared and the infant survived for the next 25 months. In the second case, an adult female adopted her infant granddaughter for nine days while the infant's mother was still a group member. In the third case, a nulliparous female temporarily adopted an infant from a neighboring group. The details and the possible reasons for these adoption are described.  相似文献   
145.
Mycoplasma genitalium is one of the smallest organisms capable of self‐replication and its sequence is considered a starting point for understanding the minimal genome required for life. MG289, a putative phosphonate substrate binding protein, is considered to be one of these essential genes. The crystal structure of MG289 has been solved at 1.95 Å resolution. The structurally identified thiamine binding region reveals possible mechanisms for ligand promiscuity. MG289 was determined to be an extracytoplasmic thiamine binding lipoprotein. Computational analysis, size exclusion chromatography, and small angle X‐ray scattering indicates that MG289 homodimerizes in a concentration‐dependant manner. Comparisons to the thiamine pyrophosphate binding homolog Cypl reveal insights into the metabolic differences between mycoplasmal species including identifying possible kinases for cofactor phosphorylation and describing the mechanism of thiamine transport into the cell. These results provide a baseline to build our understanding of the minimal metabolic requirements of a living organism. Proteins 2011. © 2010 Wiley‐Liss, Inc.  相似文献   
146.
This paper presents data on the impact of biotic pressure in terms of grazing by livestock and wood cutting by humans on the plant community in the Nilgiri Biosphere Reserve of India. Grass, and herbaceous plant biomass, number of cattle dung piles, number of woody stems available and damaged by human activities and weed biomass were assessed at different proximity along transects radiating from village-forest boundary to forest interior to measure the ecological impact of livestock grazing and fire wood collection. The grass biomass was positively correlated to overgrazing indicating the adverse effect on natural vegetation by cattle. Woodcutting was intense along the forest boundary and significantly declined as distance increased. Similarly, weed biomass and number of thorny species declined positively with proximity from village-forest boundary and the weed biomass was significantly higher in the pastoral sites compared to residential sites. The results suggest that human impact adversely affects natural vegetation and promotes weed proliferation in forest areas adjoining human settlements in the ecologically important Nilgiri Biosphere Reserve. Continued anthropogenic pressure could cause reduction in fodder availability to large herbivores like elephants, which in turn leads to an increase in human–elephant conflict.  相似文献   
147.
Invasion of hepatocytes by sporozoites is essential for Plasmodium to initiate infection of the mammalian host. The parasite's subsequent intracellular differentiation in the liver is the first developmental step of its mammalian cycle. Despite their biological significance, surprisingly little is known of the signalling pathways required for sporozoite invasion. We report that sporozoite invasion of hepatocytes requires signalling through two second‐messengers – cGMP mediated by the parasite's cGMP‐dependent protein kinase (PKG), and Ca2+, mediated by the parasite's calcium‐dependent protein kinase 4 (CDPK4). Sporozoites expressing a mutated form of Plasmodium berghei PKG or carrying a deletion of the CDPK4 gene are defective in invasion of hepatocytes. Using specific and potent inhibitors of Plasmodium PKG and CDPK4, we demonstrate that PKG and CDPK4 are required for sporozoite motility, and that PKG regulates the secretion of TRAP, an adhesin that is essential for motility. Chemical inhibition of PKG decreases parasite egress from hepatocytes by inhibiting either the formation or release of merosomes. In contrast, genetic inhibition of CDPK4 does not significantly decrease the number of merosomes. By revealing the requirement for PKG and CDPK4 in Plasmodium sporozoite invasion, our work enables a better understanding of kinase pathways that act in different Plasmodium stages.  相似文献   
148.
A method of cultivating Brucella abortus S19 culture in bioreactor was attempted using three different media. Culture conditions in bioreactor were optimized by varying agitation and aeration parameters. Varying the aeration ranging from 0.5 vvm to 0.8 vvm and agitation rate ranging from 250 rpm to 400 rpm during bacterial growth was found to yield highest viable count within 48 hours of culture period. A count of > 1 x 10(11) CFU per ml within 48 to 60 hours post seeding was obtained consistently in all five consecutive batches (P > 0.05) with 6 x 10(11) CFU per ml being the maximum yield when the organism is grown in soyabean casein digest medium. B. abortus S19 maintained its smooth characteristics throughout its growth in bioreactor. The vaccine prepared with soyabean casein digest medium was found to be potent and safe with a protective index of 3.33 in mice. The vaccine was tested in 10 cattle calves of 3 to 13 months age and all the vaccinated animals were seropositive on 28, 60, 90, 120 and 150 days post-vaccination when analyzed by fluorescence polarization assay (FPA).  相似文献   
149.
A key characteristic of human language efficiency is that more frequently used words tend to be shorter in length—the ‘law of brevity’. To date, no test of this relationship between frequency of use and length has been carried out on non-human animal vocal communication. We show here that the vocal repertoire of the Formosan macaque (Macaca cyclopis) conforms to the pattern predicted by the law of brevity, with an inverse relationship found between call duration and rate of utterance. This finding provides evidence for coding efficiency in the vocal communication system of this species, and indicates commonality in the basic structure of the coding system between human language and vocal communication in this non-human primate.  相似文献   
150.
I studied the process of adult male replacement and social change in two one- male troops (B20 and B21) of hanuman langurs (Presbytis entellus)at Jodhpur, India. Male-male competition lasted for about 6 months before the successful takeover of one troop (B20). During that period, five adult males from three neighboring bands (AMB7, AMB9, and AMB10) and a resident male of a neighboring troop (B21) were involved in taking over the troop. The latter male also copulated with six females during his interim residency, which suggests that he may have opportunistically maximized his mating chances with females of a neighboring group. During an intertroop interaction, a 14-month-old female infant of the other troop (B21) was fatally attacked by an adult female of the first troop and the infant eventually died. The attacker may have taken advantage of the disorganization created by male-male competition, perhaps to eliminate a future food competitor. In addition, the first troop gained an additional feeding area from the other troop’s range; it included a sleeping site and a waterhole, indicating that territorial fights during social instability may have led to the expansion of the winner’s resource area.  相似文献   
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