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101.
Galectins, beta-galactoside-binding lectins, are extensively distributed in the animal kingdom and share some basic molecular properties. Galectin-3, a member of this family, is generally associated with differentiation, morphogenesis, and metastasis. In this study, galectin-3 was isolated from ovine placental cotyledons round the middle of the gestation period by lactose extraction followed by affinity chromatography on lactosyl-agarose, and separated from galectin-1 by size exclusion chromatography on a Superose 12 column. Under native conditions this lectin behaved as a monomer with an apparent molecular weight of approximately 29,000 and an isoelectric point of 9.0. The partial amino acid sequence of the peptides obtained by tryptic digestion of this protein followed by HPLC separation showed striking homology with other members of the galectin-3 subfamily. Furthermore, ovine placental galectin-3 exhibited specific mitogenic activity toward rat spleen mononuclear cells. Besides, this protein strongly reacted with a rabbit antiserum raised against a chicken galectin. Results obtained by Western blot analysis showed that its expression was greatly decreased in term placenta with respect to the middle of the gestation period, suggesting a regulated expression throughout development.   相似文献   
102.
In the present study, bee colonies were smoked with tobacco smoke in order to evaluate the monthly changes in the numbers of worker bees, the infestation rates of worker bees and queens with bee lice, and the annual average honey production per colony. In July of each year, 12 colonies were smoked with tobacco smoke; the remaining hives not smoked with tobacco smoke served as the control. The results indicated that the applications of tobacco smoke during July gave rise to an impressive reduction in the Braula infestation rate on workers (below 1.8%) and reduced the amount of bee lice on the queen to zero throughout the 2–3 months following smoke treatment. In the colonies not treated with smoke, the Braula infestation rates on worker bees started to increase in May and continued to increase constantly during the rest of year, reaching maximum infestation rates of 28.2% and 33.8% in December, with an average of 15 and 17 lice per queen in November in the first and second years, respectively. Worker bee populations peaked in April and July of each year in both treatments. The average honey production per colony was significantly higher in the colonies treated with smoke than those that were not for the first and second years. In conclusion, early summer months may be the crucial time to smoke the colonies with tobacco smoke in order to keep bee lice at low levels for the remaining seasons.  相似文献   
103.

Background

HTLV-I infection has been linked to lung pathology and HTLV-II has been associated with an increased incidence of pneumonia and acute bronchitis. However it is unknown whether HTLV-I or -II infection alters pulmonary function.

Methods

We performed pulmonary function testing on HTLV-I, HTLV-II and HTLV seronegative subjects from the HTLV outcomes study (HOST), including vital capacity (VC), forced expiratory volume in one second (FEV1), and diffusing lung capacity for carbon monoxide (DLCO) corrected for hemoglobin and lung volume. Multivariable analysis adjusted for differences in age, gender, race/ethnicity, height and smoking history.

Results

Mean (standard deviation) pulmonary function values among the 257 subjects were as follows: FVC = 3.74 (0.89) L, FEV1 = 2.93 (0.67) L, DLCOcorr = 23.82 (5.89) ml/min/mmHg, alveolar ventilation (VA) = 5.25 (1.20) L and DLCOcorr/VA = 4.54 (0.87) ml/min/mmHg/L. There were no differences in FVC, FEV1 and DLCOcorr/VA by HTLV status. For DLCOcorr, HTLV-I and HTLV-II subjects had slightly lower values than seronegatives, but neither difference was statistically significant after adjustment for confounding.

Conclusions

There was no difference in measured pulmonary function and diffusing capacity in generally healthy HTLV-I and HTLV-II subjects compared to seronegatives. These results suggest that previously described HTLV-associated abnormalities in bronchoalveolar cells and fluid may not affect pulmonary function.  相似文献   
104.
Flies (Diptera: Muscidae) that breed in faeces and other organic refuse (filth flies) have been implicated as vectors of pathogenic bacteria including Escherichia coli O157:H7, which cause haemorrhagic colitis in humans, and Campylobacter, which is the principal causative agent of human enteritis. The potential role of filth flies in the epidemiology of these pathogens in the United States was investigated by examining the prevalence of Campylobacter spp. and E. coli O157:H7 from two Arkansas turkey facilities. Polymerase chain reaction was conducted on DNA extractions of individual Musca domestica Linnaeus, Stomoxys calcitrans (Linnaeus), Hydrotaea aenescens (Wiedemann), Adia cinerella Fallen and turkey faecal samples using primers specific for E. coli H7, O157 and Campylobacter spp. Culturing verified that the flies were carrying viable Campylobacter spp. and E. coli O157:H7. Results from this study indicated that M. domestica, S. calcitrans, H. aenescens and Anthomyids are capable of carrying Campylobacter in North American poultry facilities and that the E. coli O157:H7 is carried by house flies and black dump flies associated with poultry. This PCR method provided a rapid and effective method to identify Campylobacter spp. and E. coli O157:H7 directly from individual filth flies.  相似文献   
105.
The long (4.6-kb) A+T region of Drosophila melanogaster mitochondrial DNA has been cloned and sequenced. The A+T region is organized in two large arrays of tandemly repeated DNA sequence elements, with nonrepetitive intervening and flanking sequences comprising only 22% of its length. The first repeat array consists of five repeats of 338-373 bp. The second consists of four intact 464-bp repeats and a fifth partial repeat of 137 bp. Three DNA sequence elements are found to be highly conserved in D. melanogaster and in several Drosophila species with short A+T regions. These include a 300-bp DNA sequence element that overlaps the DNA replication origin and two thymidylate stretches identified on opposite DNA strands. We conclude that the length heterogeneity observed in the A+T regulatory region in mitochondrial DNAs from the genus Drosophila results from the expansion (and contraction) of the number of repeated DNA sequence elements. We also propose that the 300-bp conserved DNA sequence element, in conjunction with another primary sequence determinant, perhaps the adjacent thymidylate stretch, functions in the regulation of mitochondrial DNA replication.   相似文献   
106.
Twenty-five years ago, Arctomecon humilis, a pollinator-dependent, endangered poppy globally restricted to the extreme northeastern Mojave Desert in southwestern Utah, was pollinated by native bee species and the European honey bee. Follow-up studies beginning in 2012 failed to find the two most important native bee pollinator species, one of which, Perdita meconis, is a strict poppy specialist. We had four objectives: (1) confirm the status of formerly important native bee pollinators; (2) determine the role of the Africanized honey bee which reportedly invaded southern Utah in 2008; (3) examine the effect of the ostensible change in pollinator fauna on fruit set in four populations; (4) describe the pollination proficiency of species that presently visit poppy flowers. For the fourth consecutive survey, P. meconis was absent; its local extinction in Utah now seems certain. Another previously important native pollinator, Eucera quadricincta, was very rare. Also uncommon was the European honey bee, having been largely replaced by Africanized honey bees which have become, in most populations, the prevalent pollinator. Africanized bees forage early in the day and quickly strip flowers of their copious pollen leaving little for native bees. We argue that the invasion of southern Utah by Africanized bees is the most likely cause of the severe disruption of the A. humilis pollination system. The ascension of the Africanized bee is also associated with reduced fruit set in all poppy populations, especially those where plants are sparse. Arctomecon humilis now appears to depend mostly on an invasive species for pollination.  相似文献   
107.
Determination of predictive biomarkers by immunohistochemistry (IHC) relies on antibodies with high selectivity. RNA in situ hybridization (RNA ISH) may be used to confirm IHC and may potentially replace it if suitable antibodies are not available or are insufficiently selective to discriminate closely related protein isoforms. We validated RNA ISH as specificity control for IHC and as a potential alternative method for selecting patients for treatment with MET inhibitors. MET, the HGF receptor, is encoded by the MET proto-oncogene that may be activated by mutation or amplification. MET expression and activity were tested in a panel of control cell lines. MET could be detected in formalin fixed paraffin, embedded (FFPE) samples by IHC and RNA ISH, and this was confirmed by sandwich immunoassays of fresh frozen samples. Gastric cancer cell lines with high MET expression and phosphorylation of tyrosine-1349 respond to the MET inhibitor, BAY-853474. High expression and phosphorylation of MET is a predictive biomarker for response to MET inhibitors. We then analyzed MET expression and activity in a matched set of FFPE vs. fresh frozen tumor samples consisting of 20 cases of gastric cancer. Two of 20 clinical samples investigated exhibited high MET expression with RNA ISH and IHC. Both cases were shown by sandwich immunoassays to exhibits strong functional activity. Expression levels and functional activity in these two cases were in a range that predicted response to treatment. Our findings indicate that owing to its high selectivity, RNA ISH can be used to confirm findings obtained by IHC and potentially may replace IHC for certain targets if no suitable antibodies are available. RNA ISH is a valid platform for testing predictive biomarkers for patient selection.  相似文献   
108.
不孕不育患者解脲脲原体菌株血清型别的检测   总被引:2,自引:0,他引:2  
本文以解脲脲原体标准菌株1-14型免疫家获得UU1-14型抗血清。用IDT法对48株自不孕不育患者分离的地方株作分型试验。结果在1.2.4.5.6.7.8和12血八个清型中出现强阳性反应,其中4型最多。另有4株混合型。对四种血清型无反应。  相似文献   
109.
Food waste is one of the major global challenges that have adverse socioeconomic and environmental impacts. Therefore, studying food waste utilization potentials and minimizing its negative consequences becomes imperative. This study aims to assess the technical and economic potentials of substituting corn with unconventional extruded dried Arabic Bread waste (EDABW) in broilers’ diets, in terms of broilers’ performance, carcass characteristic, economic net returns, and income over feed cost (IOFC). One hundred eighty unsexed one-day-old broiler birds of Ross breed were distributed randomly in six treatments (0, 20, 40, 60, 80, and 100% EDABW group) of isocaloric and isonitrogenous diets in a completely randomized design with six replicated (5 chicks/replicate). The investigated traits were broilers’ performance (live body weight, total feed intake, total feed conversion ratio, and total weight gain. Other traits such as carcass weight, abdominal fat, edible offal (liver, heart, and gizzard), eviscerated (breast muscles, drum and thigh muscles, and wings) were weighed and expressed based on a live body weight. Results showed that the 20% replacement level of corn with EDABW generated the highest increase in the live body weight and the eviscerated carcass at about 4.24% g and 4.90%, respectively. On the other hand, the economic analysis showed potential reductions in the broilers’ diet cost and the total broilers' production cost as the levels of corn substitution with by unconventional EDABW increased. The reductions were estimated at 5.1%, 6.3%, 8.4%, 9.3%, and 9.9% at substitution levels of 20%, 40%, 60%, 80%, and 100%, respectively as compared to the control diet. The results also showed a potential increase in the net economic returns of broiler meat as the increase in substitution levels ranged between 3.5–06.8% and 4.3–8.3% as compared to the control diets using the average retail and wholesale prices of broiler meats, respectively. In addition, the maximum IOFC was estimated potentially at a 20% substitution level of corn with EDABW. Conclusively, the study results show promising technical and economic potentials for unconventional EDABW in broilers’ diets that could lead to a thriving industry of unconventional broilers’ diets with high net economic returns and maximum IOFC.  相似文献   
110.
Isospora dawadimiensis n. sp. is described from the jerboa, Jaculus jaculus, from Dawadimi, Saudi Arabia. Sporulated oocysts of I. dawadimiensis n. sp. were ovoidal or nearly subspherical 22–26.5 times 20.5–22 μm (24.4 times 21.4 μm). Oocyst wall had one layer. Micropyle, oocyst residuum, and polar granule were absent. Sporocysts were ellipsoid 12–16.5 times 9–10.5 μm (14.6 times 9.9 μm). Sporocyst residuum was present. The sporocysts lack a Stieda body. Sporozoites 8–11 times 2–3 μm (10 times 2.6 μm) were sausage-shaped, slightly curved, and tapered at one end.  相似文献   
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