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1.
Joseph B. MacInnis 《CMAJ》1966,95(5):191-200
Recent undersea experiments in the United States and France showed that divers can live and work effectively for many days from dwellings placed on the continental shelf to depths down to 432 feet. If prolonged exposure to the hostile underwater environment is to be tolerated successfully, existing physical, biological and equipment hazards must be recognized, prepared for and, when possible, circumvented.  相似文献   
2.
Using a human αB-crystallin genomic probe and human-mouse somatic cell hybrids, the human αB-gene was assigned to chromosome 11 and further corroborated by in situ hybridization to normal metaphase chromosomes. This assignment confirmed and regionally mapped the locus to q22.3–23.1.  相似文献   
3.
A number of different methods, involving direct DNA delivery are now available for plant transformation. Here we review the most recently developed technique which involves the mixing of silicon carbide whiskers with plant cells and plasmid DNA. Fertile transgenic plants have now been produced using whisker-mediated transformation, and this method can now be considered as a simple, inexpensive alternative for plant transformation. A brief review on transformation of animal cells andChlamydomonas using whiskers technology is also included.  相似文献   
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Climate change is redistributing marine and terrestrial species globally. Life‐history traits mediate the ability of species to cope with novel environmental conditions, and can be used to gauge the potential redistribution of taxa facing the challenges of a changing climate. However, it is unclear whether the same traits are important across different stages of range shifts (arrival, population increase, persistence). To test which life‐history traits most mediate the process of range extension, we used a 16‐year dataset of 35 range‐extending coral‐reef fish species and quantified the importance of various traits on the arrival time (earliness) and degree of persistence (prevalence and patchiness) at higher latitudes. We show that traits predisposing species to shift their range more rapidly (large body size, broad latitudinal range, long dispersal duration) did not drive the early stages of redistribution. Instead, we found that as diet breadth increased, the initial arrival and establishment (prevalence and patchiness) of climate migrant species in temperate locations occurred earlier. While the initial incursion of range‐shifting species depends on traits associated with dispersal potential, subsequent establishment hinges more on a species’ ability to exploit novel food resources locally. These results highlight that generalist species that can best adapt to novel food sources might be most successful in a future ocean.  相似文献   
6.
The International Plant Proteomics Organization (INPPO) is a non‐profit organization whose members are scientists involved or interested in plant proteomics. Since the publication of the first INPPO highlights in 2012, continued progress on many of the organization's mandates/goals has been achieved. Two major events are emphasized in this second INPPO highlights. First, the change of guard at the top, passing of the baton from Dominique Job, INPPO founding President to Ganesh Kumar Agrawal as the incoming President. Ganesh K. Agrawal, along with Dominique Job and Randeep Rakwal initiated the INPPO. Second, the most recent INPPO achievements and future targets, mainly the organization of first the INPPO World Congress in 2014, tentatively planned for Hamburg (Germany), are mentioned.  相似文献   
7.
While a suite of approaches have been developed to describe the scale, rate and spatial structure of exchange among populations, a lack of mechanistic understanding will invariably compromise predictions of population-level responses to ecosystem modification. In this study, we measured the energetics and sustained swimming capacity of giant Australian cuttlefish Sepia apama and combined these data with information on the life-history strategy, behaviour and circulation patterns experienced by the species to predict scales of connectivity throughout parts of their range. The swimming capacity of adult and juvenile S. apama was poor compared to most other cephalopods, with most individuals incapable of maintaining swimming above 15 cm s−1. Our estimate of optimal swimming speed (6–7 cm s−1) and dispersal potential were consistent with the observed fine-scale population structure of the species. By comparing observed and predicted population connectivity, we identified several mechanisms that are likely to have driven fine-scale population structure in this species, which will assist in the interpretation of future population declines.  相似文献   
8.

Background

Each year, thousands of pilgrims travel to the Janai Purnima festival in Gosainkunda, Nepal (4380 m), ascending rapidly and often without the aid of pharmaceutical prophylaxis.

Methods

During the 2012 Janai Purnima festival, 538 subjects were recruited in Dhunche (1950 m) before ascending to Gosainkunda. Through interviews, subjects provided demographic information, ratings of AMS symptoms (Lake Louise Scores; LLS), ascent profiles, and strategies for prophylaxis.

Results

In the 491 subjects (91% follow-up rate) who were assessed upon arrival at Gosainkunda, the incidence of AMS was 34.0%. AMS was more common in females than in males (RR = 1.57; 95% CI = 1.23, 2.00), and the AMS incidence was greater in subjects >35 years compared to subjects ≤35 years (RR = 1.63; 95% CI = 1.36, 1.95). There was a greater incidence of AMS in subjects who chose to use garlic as a prophylactic compared to those who did not (RR = 1.69; 95% CI = 1.26, 2.28). Although the LLS of brothers had a moderate correlation (intraclass correlation = 0.40, p = 0.023), sibling AMS status was a weak predictor of AMS.

Conclusions

The incidence of AMS upon reaching 4380 m was 34% in a large population of Nepalese pilgrims. Sex, age, and ascent rate were significant factors in the development of AMS, and traditional Nepalese remedies were ineffective in the prevention of AMS.  相似文献   
9.
Some mammals hibernate in response to harsh environments. Although hibernating mammals may metabolize proteins, the nitrogen metabolic pathways commonly activated during hibernation are not fully characterized. In contrast to the hypothesis of amino acid preservation, we found evidence of amino acid metabolism as three of five key enzymes, including phenylalanine hydroxylase (PAH), homogentisate 1,2-dioxygenase (HGD), fumarylacetoacetase (FAH), involved in phenylalanine and tyrosine catabolism were co-upregulated during hibernation in two distantly related species of bats, Myotis ricketti and Rhinolophus ferrumequinum. In addition, the levels of phenylalanine in the livers of these bats were significantly decreased during hibernation. Because phenylalanine and tyrosine are both glucogenic and ketogenic, these results indicate the role of this catabolic pathway in energy supply. Since any deficiency in the catabolism of these two amino acids can cause accumulations of toxic metabolites, these results also suggest the detoxification role of these enzymes during hibernation. A higher selective constraint on PAH, HPD, and HGD in hibernators than in non-hibernators was observed, and hibernators had more conserved amino acid residues in each of these enzymes than non-hibernators. These conserved amino acid residues are mostly located in positions critical for the structure and activity of the enzymes. Taken together, results of this work provide novel insights in nitrogen metabolism and removal of harmful metabolites during bat hibernation.  相似文献   
10.
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