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971.
The response of the late second-instar male nymphs of the mealybug species (Hemiptera, Pseudococcidae), Planococcus citri (Risso), Planococcus ficus (Signoret), Pseudococcus cryptus Hempel Nipaecoccus viridis (Newstead), to their conspecific and heterospecific female pheromone was studied. Males that exhibited the typical appearance of late-second-instar nymphs were tested. The male behavior was monitored soon after their exposure to the tested female sex pheromone in glass Petri dish arenas. Male nymph behavior toward the pheromone source was characterized based on their aggregation on the disks in the arena. Males of all four tested mealybug species were attracted to their conspecific female pheromone. By contrast, almost no interceptions of male nymphs with disks impregnated with a heterospecific female pheromone were observed. The mode of attraction of each of male nymphs of P. ficus, among most of the tested individuals (>80%), to the conspecific female sex pheromone, (S)-lavandulyl senecioate and or (S)-lavandulyl isovalerate, was the same as the mode of attraction latter on as adult. We suggest that by being attracted to the conspecific pheromone these males may direct themselves to a suitable pupation site near conspecific non-sibling mature females, thus preventing inbreeding. The repellency of heterospecific sex pheromone to males that are looking for a pupation site suggests that the latter try to avoid close contact with heterospecific females.  相似文献   
972.
Human rotavirus-specific CD4(+) and CD8(+) T-cell responses in peripheral blood lymphocytes were studied using a flow cytometric assay that detects the intracellular accumulation of cytokines after short-term in vitro antigen stimulation. The frequencies of virus-specific T cells that secrete gamma interferon and interleukin-13 (IL-13) were determined in adults and children during the acute or convalescent phase of rotavirus-induced diarrhea, in asymptomatically infected adults and laboratory workers who worked with human stool samples containing rotavirus, and in healthy adults. Significantly higher frequencies of rotavirus-specific interferon gamma-secreting CD8(+) and CD4(+) T cells, but not IL-13-secreting T cells, were detected in symptomatically infected adults and exposed laboratory workers than in healthy adults and children with acute rotavirus diarrhea. The levels of rotavirus-specific T cells returned to levels found in healthy adults by 32 days after the onset of rotavirus diarrhea in most adult subjects. Children with rotavirus diarrhea had undetectable or very low levels of CD4(+) and CD8(+) T cells that secrete gamma interferon. Adult cytomegalovirus-seropositive individuals had frequencies of cytomegalovirus-specific T cells that secrete gamma interferon that were approximately 20 times the level of rotavirus-specific T cells. This result suggests that rotavirus is a relatively poor inducer of circulating memory T cells that secrete gamma interferon. The frequencies of gamma interferon-secreting CD4(+) and CD8(+) T cells and the frequencies of IL-13-secreting CD4(+) T cells responding to the T-cell superantigen staphylococcal enterotoxin B (SEB) were lower in children than in adults. In both adults and children, the frequencies of CD4(+) cells secreting gamma interferon in response to SEB were higher than the frequencies of cells secreting IL-13.  相似文献   
973.
Objective: Our objective was to test the effect of biliopancreatic diversion (BDP) in adiponectin multimerization. Adiponectin, the major protein secreted by adipose tissue, circulates in plasma in different isoforms. The most clinically relevant oligomers are high‐molecular weight (HMW) multimers and low‐molecular weight (LMW) trimers. Contrasting data on the effect of weight loss on adiponectin isoforms have been reported. Research Methods and Procedures: We measured total plasma adiponectin and HMW and LMW adiponectin oligomers (by Western blot analysis) before and 1 month after BPD, in 18 severely obese subjects. Results: One month after BPD, body weight decreased ~11%. Total adiponectin showed significant increase after BPD. In addition, we found a significant increase in HMW (percentage) adiponectin oligomers. We found a significant inverse correlation between HMW (percentage) and BMI before and after BPD. Homeostasis model of assessment‐insulin resistance decreased significantly after the BPD, without any significant correlation with total serum adiponectin and adiponectin oligomers. Discussion: A moderate weight loss after BPD increases total and HMW adiponectin oligomers. The significant correlation between BMI and HMW (percentage) adiponectin oligomers but not between BMI and total adiponectin might indicate a role of body fat mass in regulation of adiponectin multimerization. These data suggest that HMW oligomers represent a very sensitive parameter to short‐term BMI changes after BPD.  相似文献   
974.
This study was focused on obtaining the complete gene sequence of the toxR gene in V. harveyi by using toxR-targeted PCR to amplify 5' and 3' regions flanking the 576-bp Vibrio harveyi (NBRC 15634) toxR gene fragment previously amplified using degenerate PCR. To obtain the 5' flanking sequences, a forward PCR primer (VhtoxRpv) was designed based on known sequences upstream of toxR in V. parahaemolyticus and V. vulnificus. The reverse primer (VctoxR2R) was based on the sequence of the 576-bp Vibrio harveyi toxR fragment. The resulting 750-bp amplicon was sequenced, providing the 5' sequences of the V. harveyi (NBRC 15634) toxR gene. The 3' flanking region was amplified using a primer pair toxRS1 and toxRS2 based on V. parahaemolyticus and V. vulnificus toxR and toxS, resulting in a 900-bp amplicon that contained the remaining 3' sequences of the V. harveyi NBRC 15634 toxR. This paper reports, for the first time, a complete 882-bp nucleotide sequence for toxR in Vibrio harveyi. Sequence analysis and alignment revealed that the complete toxR gene in V. harveyi shares 87% sequence similarity with toxR of V. parahaemolyticus, 84% similarity with V. fluvialis, 83% with V. vulnificus and partial sequence of V. campbellii. The phylogenetic trees revealed wider divergence in toxR compared to 16S rRNA genes, so that V. harveyi could easily be distinguished from V. campbellii and V. parahaemolyticus.  相似文献   
975.

Background

The potential role of DSS in CVD prevention remains unclear as only a few studies report on patient outcomes for cardiovascular disease.

Methods and Results

A systematic review and meta-analysis of randomised controlled trials and observational studies was done using Medline, Embase, Cochrane Library, PubMed, Amed, CINAHL, Web of Science, Scopus databases; reference lists of relevant studies to 30 July 2011; and email contact with experts. The primary outcome was prevention of cardiovascular disorders (myocardial infarction, stroke, coronary heart disease, peripheral vascular disorders and heart failure) and management of hypertension owing to decision support systems, clinical decision supports systems, computerized decision support systems, clinical decision making tools and medical decision making (interventions). From 4116 references ten studies met our inclusion criteria (including 16,312 participants). Five papers reported outcomes on blood pressure management, one paper on heart failure, two papers each on stroke, and coronary heart disease. The pooled estimate for CDSS versus control group differences in SBP (mm of Hg) was - 0.99 (95% CI −3.02 to 1.04 mm of Hg; I2 = 0; p = 0.851).

Conclusions

DSS show an insignificant benefit in the management and control of hypertension (insignificant reduction of SBP). The paucity of well-designed studies on patient related outcomes is a major hindrance that restricts interpretation for evaluating the role of DSS in secondary prevention. Future studies on DSS should (1) evaluate both physician performance and patient outcome measures (2) integrate into the routine clinical workflow with a provision for decision support at the point of care.  相似文献   
976.
Unsaturated lipids when exposed to air at room temperature undergo a slow autoxidation. When fullerene C60 was dissolved in selected lipids (ethyl oleate, ethyl linoleate, linseed oil and castor oil) the spectrophotometric analysis shows that the oxidation is concentrated to C60 which is converted to an epoxide C60O. Thus, fullerene C60 displays antioxidant activity not only when dissolved in unsaturated lipids but also, more generally, when dissolved in unsaturated solvents subjected to autoxidation like, for example, in cyclohexene. The behaviour of C60 in ethyl oleate has been compared with that of the known antioxidant TMPPD (N,N′,N,N,′-tetramethyl-p-phenylenediamine) in ethyl oleate. The mechanism of the antioxidant action of C60 in lipids has been proposed. The kinetics of C60 oxidation in lipids was determined spectrophotometrically both at room temperature in the dark and under UV irradiation. The oxidized products derived from C60 photo-oxidation in lipids have been identified.  相似文献   
977.
The occurrence of a species in habitats of varying quality connected through migration can only be understood by detailed investigation of itsdemography. In the Chihuahuan Desert, the common shrub Flourensia cernua is found in both productive and unproductive areas. In the former, both growing and senescent populations are regularly found, while in the latter a low density scattered population persists indefinitely. While precipitation (and its annual stochastic variation) is the same in both habitats, their geomorphological differences produce a sharp difference in the availability of the limiting resource, water. This produces different population dynamics in F. cernua, but also radically different plant communities. Counterintuitively, the low‐resource habitat (LR) supports a scattered, slightly increasing or stable population that coexists with its neighbors and acts as exporter of seeds (source population). In contrast, the high‐resource habitat (HR) allows sporadic recruitment of locally dense patches that tend towards extinction (sink population). The latter is accounted for by the increasing dominance of the grass Pleuraphys mutica. The different dynamics and regulatory mechanisms in each habitat allow the species to occupy a wider distribution than it would have in their absence. The higher abundance of F. cernua in the sink habitat, together with its consequences on community composition and dynamics, questions the idea proposed in the literature that a sink population lives outside its fundamental niche. The study provides support to the notion that the ecological niche of a species cannot be completely characterized by its requirements (e.g. as they relate to physiology), but must also include the complex demographic responses to a spatially and temporally variable environment, which may often include substandard conditions. For the niche concept to retain its usefulness, it must incorporate the demographic response of populations to spatially and temporallyvariable resource supply.  相似文献   
978.
Transgenesis in cattle has provided numerous opportunities for livestock production. The development of nuclear transfer (NT) technology has improved the production of transgenic livestock. However, the isolation of pure colonies from a single transfection event remains laborious and can be a constraint in the production of transgenic livestock. We used 96-well cell culture plates to isolate cell lineages obtained from a single fibroblast transfected with the pCi-Neo plasmid. Since single mammalian cells do not grow well in fresh medium, we evaluated the use of conditioned medium. The neomycin phosphotransferase gene was detected in isolated colonies and NT embryos were produced from these cells. Multiplex-PCR assays were performed to detect the transfected fragment as well as autosomal satellite DNA in single NT embryos. This approach provided a reliable method for isolating transfected mammalian cells and for diagnosing the incorporation of desirable vectors in NT embryos. This method can reduce the time and cost of transgenic livestock production.  相似文献   
979.
Llama (Lama glama) and alpaca (Vicugna pacos) are the only large domesticated animals indigenous to the Americas. Pastoralism occupies a fundamental economic, social and religious role in Andean life. Today, camelid livestock are confined to the ecozone of the puna (above 3,500 masl), while their presence on the Pacific coast during pre-Hispanic times is attested by archaeological skeletal remains. This study aims to document herding practices on the northern Peruvian coast during the Early Intermediate Period (200 BC-600 AD) by gaining insights into diet, location of breeding and mobility of archaeological camelids from the funerary and ritual contexts of two Mochica sites, Uhle Platform in Huacas de Moche and El Brujo. The three first early years and the long-term life histories of the animals were documented by the combined bulk analysis of bone collagen (δ13Ccol and δ15Ncol) and bone structural carbonate (δ13Cbone and δ18Obone) and the serial analysis of structural carbonate of molar tooth enamel (δ13Cenamel and δ18Oenamel). Mochica camelids were bred in the low and/or middle valleys, unlike their modern counterparts, who are restricted to highland puna C3 pastures. Archaeological camelids had diverse and complex life histories, usually with substantial maize foddering. An ontogenetic switch in diet and possible residential mobility during the course of life were identified for some specimens. Although the inference of geographic origin from δ18Obone and δ18Oenamel values was limited because of the lack of understanding of the influence of environmental and biological factors, tooth enamel analysis has great potential for exploring camelid herding practices and Andean pastoralism. Our study suggested that Mochica herders adapted their practices to the difficult lowland environment and that herding practices were varied and not restricted to breeding at higher altitudes. The role of maize in different aspects of the economic life of the Mochicas is also underlined.  相似文献   
980.
The success of postnatal uterine morphogenesis dictates, in part, the embryotrophic potential and functional capacity of the adult uterus. The definitive role of Wnt7a in postnatal uterine development and adult function requires a conditional knockout, because global deletion disrupts müllerian duct patterning, specification, and cell fate in the fetus. The Wnt7a-null uterus appears to be posteriorized because of developmental defects in the embryo, as evidenced by the stratified luminal epithelium that is normally found in the vagina and the presence of short and uncoiled oviducts. To understand the biological role of WNT7A after birth and allow tissue-selective deletion of Wnt7a, we generated loxP-flanked exon 2 mice and conditionally deleted Wnt7a after birth in the uterus by crossing them with Pgr(Cre) mice. Morphological examination revealed no obvious differences in the vagina, cervix, oviduct, or ovary. The uteri of Wnt7a mutant mice contained no endometrial glands, whereas all other uterine cell types appeared to be normal. Postnatal differentiation of endometrial glands was observed in control mice, but not in mutant mice, between Postnatal Days 3 and 12. Expression of morphoregulatory genes, particularly Foxa2, Hoxa10, Hoxa11, Msx1, and Wnt16, was disrupted in the Wnt7a mutant uteri. Conditional Wnt7a mutant mice were not fertile. Although embryos were present in uteri of mutant mice on Day 3.5 of pregnancy, blastocyst implantation was not observed on Day 5.5. Furthermore, expression of several genes (Foxa2, Lif, Msx1, and Wnt16) was reduced or absent in adult Wnt7a-deleted uteri on Day 3.5 postmating. These results indicate that WNT7A plays a critical role in postnatal uterine gland morphogenesis and function, which are important for blastocyst implantation and fertility in the adult uterus.  相似文献   
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