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1.
Of 153 clinical isolates of shigellae examined, 64.7% belonged toShigella flexneri, 18.9% toSh. sonnei, 11.8% toSh. boydii and 4.6% toSh. dysenteriae. Part of these isolates were resistant to sulfamethoxazole and streptomycin (88.2% each), ampicillin (66.70, tetracycline (63.40 and co-trimoxazole (43.10, with levels of resistance (MIC50 and MIC90) being invariably high. Resistance to three or more drugs (multidrug resistance) was seen in 77.8% of the isolates. All the 25 strains examined for transfer of resistance contained R-plasmids, both autotransferable and non-autotransferable (mobilized by transfer factor X). The frequency of transfer of different r-determinants varied from 2.7 · 10–8 to 1.4 · 10.  相似文献   
2.
Role of endogenous opioids and histamine in morphine induced emesis   总被引:1,自引:0,他引:1  
The role of opioid and histaminergic system in morphine induced emesis was investigated in dogs. Morphine (25 micrograms, icv) consistently evoked emesis with an average latency of 195 +/- 29 sec which was fully accounted for by an action on the chemoreceptor trigger zone (CTZ) as its ablation rendered animals refractory to vomiting. Intraventricular pretreatment with opioid antagonist naloxone, histamine H1 antagonist mepyramine and H2 antagonists metiamide and cimetidine afforded protection to icv morphine emesis. The CSF histamine concentration was significantly raised 5 min after icv morphine administration. The results suggest that both endogenous opioid and histamine are involved in morphine emesis. Naloxone in high doses (1600 micrograms, icv) elicited emesis which was not blocked by CTZ ablation confirming our earlier report.  相似文献   
3.
Mughees  Mohd  Chugh  Himanshu  Wajid  Saima 《Protoplasma》2020,257(2):345-352
Protoplasma - Vesicular trafficking between endoplasmic reticulum and Golgi plays a major role in the growth and proliferation of breast cancer cells. Various proteins regulate this ER-Golgi...  相似文献   
4.
Protein self-association is critical to many biological functions. However, atomic-level structural characterization of these assemblies has remained elusive. In this report we present insights into the mechanistic details of the process of self-association of the 136-residue GTPase effector domain (GED) of the endocytic protein dynamin into a megadalton-sized soluble mass. Our approach is based on NMR monitoring of regulated folding and association through Gdn-HCl titration. The results suggest the evolution of a sequence–self-association paradigm. Equally significantly, the study demonstrates an elegant bottom-up strategy that can render large protein self-assemblies accessible to NMR investigations that have remained difficult to date.  相似文献   
5.

Introduction

Although economic development is generally accompanied by improvements in the overall nutritional status of the country’s population the ‘nutritional transition’ often involves a shift to high energy diets and less exercise with negative consequences. This pilot study was done to examine if education of parents operates at the household level to influence dietary choices and the nutritional status of children in a small community of hospital workers.

Material and Methods

3 groups of persons with varying skill and education levels participated. Weighed food logs were used in all households to calculate ‘adult equivalent’ per-capita-consumption. Nutrients were calculated using nutrients calculator software. BMI was used to classify children as underweight, normal weight and overweight.

Results

128 individuals participated from 30 families included 47 children. 10 children (21%) were underweight, 29 (62%) were normal and 8 (17%) were overweight. Energy consumption was highest in families with overweight children 2692 +/-502 compared to 2259 +/-359 in families with normal weight and 2031+/-354 in the family of underweight children. These differences were statistically significant. 42% underweight children belonged to Class 1 at the lowest skill level and there were no overweight children in this group. Most of the overweight children belonged to Class 2. In Class 3 there were no underweight children and the majority was normal weight children.

Conclusion

Underweight children came from the poorer households. Per capita intake of the family as a whole correlated well with BMI in the children. There was increased obesity in middle income families belonging to Class 2—probably in families who move up the scale from deprivation. Nutritional status in children correlated mostly with maternal education status.  相似文献   
6.
The “marine world” is endowed with diverse life forms. The life under the oceans is bestowed with a unique gene pool and characteristics owing to extreme conditions such as high salt concentration and temperature variations. The marine biodiversity is an extremely rich resource for the development of a wide array of applications in food, pharmaceuticals, cosmetics. Various forms of traditional knowledge, including traditional medicinal knowledge, have been silently developing over the centuries, with the coastal tribes in nations across the globe. Unfortunately, marine traditional knowledge has been underestimated both commercially and legally. It has still not gained its due importance at the international platform for sustainable use and development. An attempt has been made in the present study to collate information on marine traditional knowledge based medicine. Recent trends of marine bioprospecting by various nations including India have been discussed, followed by the study of legal provisions dealing with marine bioprospecting that aim at conservation and sustainable use of marine biodiversity and associated traditional knowledge. Convention of Biological Diversity, United Nations Convention on the Law of the Seas and World Intellectual Property Organization are the major international legal instruments that discuss the concepts of Prior Informed Consent, access and benefit sharing with regard to biopiracy and provide guidelines and limits for conducting marine scientific research.  相似文献   
7.
The induction of conformationally restricted N-(aryl or heteroaryl)-3-azabicyclo[3.1.0]hexane derivatives at P2 region of compounds of 2-cyanopyrrolidine class was explored to develop novel DPP-IV inhibitors. The synthesis, structure–activity relationship, and selectivity against related proteases are delineated.  相似文献   
8.
9.
Activities of alcohol dehydrogenase, hexokinase, glucose-6-phosphate dehydrogenase, and 6-phosphogluconate dehydrogenase were significantly inhibited by cadmium in germinating pea (Pisum sativum L. cv. Bonneville) seeds. The effect was concentration dependent in the range of 0.25 to 1.0 mM CdCl2. The magnitude of detrimental effect on these enzymes was reduced during later stage of germination (9 d) largely because of fall in the activities of these enzymes in the control seeds germinated in water. In vitro, activities of hexokinase, glucose-6-phosphate dehydrogenase, and alcohol dehydrogenase were inhibited at 0.5 mM Cd2+ in the reaction mixture by 62, 67, and 36 %, respectively, however, 6-phosphogluconate dehydrogenase was insensitive to Cd2+. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
10.
The peptaibols are a large family of membrane-active peptides with considerable sequence homology, but with different biological properties and three-dimensional structures. They constitute a rich resource of naturally occurring 'mutants' which are potentially valuable for structure/function studies of ion channels. A searchable on-line database of sequences and structures of the peptaibols has been created at http://www.cryst.bbk.ac.uk/peptaibol, as a resource for the biological and structural community. In this paper, the contents and organization of the website are discussed as well as procedures for submission of new entries to the database. At present, more than 300 peptaibol sequences are stored in the database. Each sequence entry contains its full literature reference and information about its biological source. Tools are provided for searching for specific peptaibol sequences or groupings of sequences, and for locating peptaibols containing specified sequence motifs. In addition the website acts as a database for structural information. The coordinates of all currently available peptaibol x-ray and NMR structures are included and complemented, where appropriate. with molecular graphics illustrations. These include figures of model channel structures and comparisons between different peptaibol structures. The peptaibol database thus provides a tool for ready access to information and a means of investigating the sequences and structures of this class of polypeptides.  相似文献   
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