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61.
62.
It is universally accepted that lifestyle interventions are the first step towards a good overall, reproductive and sexual health. Cessation of unhealthy habits, such as tobacco, alcohol and drug use, poor nutrition and sedentary behavior, is suggested in order to preserve/improve fertility in humans. However, the possible risks of physical exercise per se or sports on male fertility are less known. Being “fit” does not only improve the sense of well-being, but also has beneficial effects on general health: in fact physical exercise is by all means a low-cost, high-efficacy method for preventing or treating several conditions, ranging from purely physical (diabetes and obesity) to psychological (depression and anxiety), highly influencing male reproduction. If male sexual and reproductive health could be positively affected by a proper physical activity, inadequate bouts of strength – both excessive intensity and duration of exercise training – are more likely to have detrimental effects. In addition, the illicit use of prohibited drugs (i.e. doping) has reached pandemic proportions, and their actions, unfortunately very often underestimated by both amateur and professional athletes, are known to disrupt at different levels and throughout various mechanisms the male hypothalamic-pituitary-gonadal axis, resulting in hypogonadism and infertility.  相似文献   
63.
Fifty-two stream segments were sampled from 16 August to 13 September in 1993 in the eastern Atlantic Rainforest of S?o Paulo State, southeastern Brazil (22°55′–25°00′S, 44°48′–48°03′W). Forty-two macroalgal subgeneric taxa were found and the most widespread species were Audouinella pygmaea (21% of sites), Compsopogon leptoclados and Microcoleus subtorulosus (19%). Macroalgal species number per sampling site ranged from 0 to six (2.6 ± 1.7) and was positively correlated to species abundance, whereas species cover ranged from 0 to 70% of the stream bed (15.5 ± 20.8%). No significant correlation was found among macroalgal species number and abundance with any physical or chemical variable analyzed. Most sites were dominated by one or few macroalgal species, mainly, Audouinella macrospora, C. leptoclados and M. subtorulosus. No significant difference was found between the frequency distribution of variables measured for streams and for total macroalgae but the most widespread species (A. pygmaea) differed significantly for current velocity, specific conductance, turbidity and pH. Overall means for macroalgal occurrence include the following values: temperature (% MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamiwaaaa!36CA!\[X\] = 19.9°C), current velocity (% MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamiwaaaa!36CA!\[X\] = 45 cm s−1), oxygen saturation (% MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamiwaaaa!36CA!\[X\] = 66%), specific conductance (% MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamiwaaaa!36CA!\[X\] = 59.6 μS cm−1), turbidity (% MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamiwaaaa!36CA!\[X\] = 5 NTU) and pH (% MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamiwaaaa!36CA!\[X\] = 7.1). This pattern of patchy distribution and dominance by few species has been suggested as typical of stream macroalgal communities and has been ascribed to the rapid fluctuation of physical and chemical conditions. Total macroalgal species richness as well as mean species number per sampling site were considerably lower than found in similar studies of other regions. The Intermediate Disturbance Hypothesis was applied to explain these results: the same factor (high precipitation) responsible for the maintainance of the high species diversity in the surrounding forest can be, paradoxically, a constraint to the development of a more diverse macroalgal flora in streams.  相似文献   
64.
We have designed and implemented on a personal computer a programfor identifying and quantifying the fragments present in a peptidemixture obtained by hydrolysing a polypeptide of known sequenceusing digesting agents. The qualitative data utilized by themain algorithm consist of the target sequence of the intactmolecule and the amino acid residues identified at each stepof the automatic sequence analysis of the unfractionated digestionmixture. In this way, the sequence of each fragment presentin the mixture is quickly reconstructed. Furthermore, if thequantitative data of the amino acid residues identified at eachstep of the sequence analysis are utilized, the program willcorrelate the sequence of each fragment to its amount. We furnishan example of the application intended for the rapid identificationand characterization of the extracellular proteinases producedby a basidiomycete fungus, utilizing the bovine insulin ß3-chainas target substrate. A variety of uses for the method are discussed.  相似文献   
65.
The resin of Boswellia freerana afforded in addition to the known 3β,20(S)-dihydroxydammar-24-ene, its 3-acetyl derivative and (20S)-protopanaxadiol, a new triterpene that was characterized as 3β-acetoxy-16(S),20(R)-dihydroxydammar-24-ene on the basis of chemical and physico-chemical evidence.  相似文献   
66.
The effect of altitude and season on abundance and diversity of the culturable heterotrophic bacterial and yeast community was examined at four forest sites in the Italian Alps along an altitude gradient (545–2000 m). Independently of altitude, bacteria isolated at 0 °C (psychrophiles) were less numerous than those recovered at 20 °C. In autumn, psychrophilic bacterial population increased with altitude. The 1194 bacterial strains were primarily affiliated with the classes Alpha-, Beta-, Gammaproteobacteria, Spingobacteriia and Flavobacteriia. Fifty-seven of 112 operational taxonomic units represented potential novel species. Strains isolated at 20 °C had a higher diversity and showed similarities in taxa composition and abundance, regardless of altitude or season, while strains isolated at 0 °C showed differences in community composition at lower and higher altitudes. In contrast to bacteria, yeast diversity was season-dependent: site- and altitude-specific effects on yeast diversity were only detected in spring. Isolation temperature affected the relative proportions of yeast genera. Isolations recovered 719 strains, belonging to the classes Dothideomycetes, Saccharomycetes, Tremellomycetes and Mycrobotryomycetes. The presence of few dominant bacterial OTUs and yeast species indicated a resilient microbial population that is not affected by season or altitude. Soil nutrient contents influenced significantly abundance and diversity of culturable bacteria, but not of culturable yeasts.  相似文献   
67.
Histone variants play a critical role in chromatin structure and epigenetic regulation. These “deviant” proteins have been historically considered as the evolutionary descendants of ancestral canonical histones, helping specialize the nucleosome structure during eukaryotic evolution. Such view is now challenged by 2 major observations: first, canonical histones present extremely unique features not shared with any other genes; second, histone variants are widespread across many eukaryotic groups. The present work further supports the ancestral nature of histone variants by providing the first in vivo characterization of a functional macroH2A histone (a variant long defined as a specific refinement of vertebrate chromatin) in a non-vertebrate organism (the mussel Mytilus) revealing its recruitment into heterochromatic fractions of actively proliferating tissues. Combined with in silico analyses of genomic data, these results provide evidence for the widespread presence of macroH2A in metazoan animals, as well as in the holozoan Capsaspora, supporting an evolutionary origin for this histone variant lineage before the radiation of Filozoans (including Filasterea, Choanoflagellata and Metazoa). Overall, the results presented in this work help configure a new evolutionary scenario in which histone variants, rather than modern “deviants” of canonical histones, would constitute ancient components of eukaryotic chromatin.  相似文献   
68.

Background

Bartonellosis affects small Andean communities in Peru, Colombia and Ecuador. Research in this area has been limited.

Methods

Retrospective review of 191 cases of bartonellosis managed in Caraz District Hospital, Peru, during the last outbreak (2003).

Results

The majority of cases (65%) were 14 years old and younger. There was a peak in acute cases after the rainy season; chronic cases presented more constantly throughout the year. The sensitivity of blood smear against blood culture in acute disease was 25%. The most commonly used treatment for chronic disease was rifampicin; chloramphenicol was used to treat most acute cases. Complications arose in 6.8% and there were no deaths.

Conclusions

Diagnostic and treatment algorithms for acute and chronic bartonellosis have been developed without a strong evidence base. Preparation of ready-to-go operational research protocols for future outbreaks would strengthen the evidence base for diagnostic and treatment strategies and enhance opportunities for control.  相似文献   
69.
The reaction of yeast alcohol dehydrogenase with iodoacetate produces a loss of 90% of the enzymatic activity when 2.2–2.4 equivalents of carboxymethyl groups are incorporated. After CNBr cleavage of the 14C-carboxymethylated enzyme the more radioactive fragment was maleylated and digested with trypsin. A tryptic peptide, containing about 70% of initial radioactivity, was purified and sequenced. The cysteine found to be more reactive with iodoacetate in our experimental conditions is different from that found in previous works. It also appears to differ from the cysteine residues found to be reactive towards other thiol reagents.  相似文献   
70.
Ionization of the phenolic group of N-acetyltyrosynamide has been studied using second-derivative spectroscopy. At pH 12.5 the second-derivative spectrum of the model compound revealed the presence of derivative bands in a spectral region (between 250 and 270 nm) where interference coming from other ultraviolet-absorbing chromophores is negligible. One of these peaks (260-nm peak) has been employed for the determination of tyrosyl groups in mixtures containing the aromatic amino acids.  相似文献   
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