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51.
OBJECTIVE: To test the hypothesis that maternal food fortification with omega-3 fatty acids and multiple micronutrients increases birth weight and gestation duration, as primary outcomes. DESIGN: Non-blinded, randomised controlled study. SETTING: Pregnant women received powdered milk during their health check-ups at 19 antenatal clinics and delivered at two maternity hospitals in Santiago, Chile. SUBJECT: Pregnant women were assigned to receive regular powdered milk (n = 477) or a milk product fortified with multiple micronutrients and omega-3 fatty acids (n = 495). RESULTS: Intention-to-treat analysis showed that mean birth weight was higher in the intervention group than in controls (65.4 g difference, 95% confidence interval (CI) 5-126 g; P = 0.03) and the incidence of very preterm birth (0.80 just for mean birth weight and birth length in the on-treatment analysis; birth length in that analysis had a difference of 0.57 cm (95% CI 0.19-0.96 cm; P = 0.003). CONCLUSIONS: The new intervention resulted in increased mean birth weight. Associations with gestation duration and most secondary outcomes need a larger sample size for confirmation.  相似文献   
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通过不同秧龄秧苗对水稻生育和米质的影响试验,结果表明:插秧秧龄越大株高增高,叶龄和有效穗数增加,但千粒重有降低的趋势。3.5和4.5叶龄插秧时每穗粒数最多、产量最高。插秧秧龄大,加工品质差,外观品质变坏,但食味品质提高。  相似文献   
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This is the first study to isolate, identify and characterize Streptococcus iniae as the causative disease agent in two tilapia (Oreochromis aureus) populations. The populations were geographically isolated, of distinct origins, and did not share water sources. Affected fish showed various external (e.g., exophthalmia and cachexia, among others) and internal (e.g., granulomatous septicaemia and interstitial nephritis, among others) signs. All internal organ samples produced pure cultures, two of which (one from each farm, termed S‐1 and S‐2) were subjected to biochemical, PCR and 16S rRNA sequencing (99.5% similarity) analyses, confirming S. iniae identification. The two isolates presented genetic homogeneity regardless of technique (i.e., RAPD, REP‐PCR and ERIC‐PCR analyses). Pathogenic potentials were assessed through intraperitoneal injection challenges in rainbow trout (Oncorhynchus mykiss) and zebrafish (Danio rerio). Rainbow trout mortalities were respectively 40% and 70% at 104 and 106 CFU per fish with the S‐1 isolate, while 100% mortality rates were recorded in zebrafish at 102 and 104 CFU per fish with the S‐2 isolate. The obtained data clearly indicate a relationship between intensified aquaculture activities in Mexico and new disease appearances. Future studies should establish clinical significances for the tilapia industry.  相似文献   
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  1. The spatial variation in community structure among 30 areas for the management and exploitation of benthic resources (AMEBRs) in central Chile was assessed from surveys conducted during the same spring–summer season. One hundred taxa identified in the subtidal surveys were grouped into 10 functional groups.
  2. The influence and relative importance of external factors over benthic associations were assessed through nonmetric multidimensional scaling (NMDS) and path analysis. Three main categories of external factors were considered: ‘terrain traits’ (e.g. coastline exposure), ‘surface-ocean conditions’ (e.g. sea surface temperature, SST), and ‘fishery-related variables’ (e.g. cumulative landings).
  3. The NMDS revealed a strong association between benthic community structure and both terrain and surface-ocean conditions (42% of variance explained by permutational multivariate analysis of variance), but not with fishery-related variables. Assemblages typical of rocky substrates were associated with larger seasonal fluctuations in SST and surface chlorophyll a. The presence of soft-bottom functional groups was associated with higher levels of surface fluorescence and larger seasonal fluctuations in a satellite-derived proxy for river-plume influence (nLw645).
  4. A path analysis model for hard-bottom communities reached a 49% goodness of fit (GOF), with the presence of epifaunal filter-feeders, grazers, predators, and scavengers being significantly correlated with leathery and corticated foliose algae, which in turn depend on the fraction of rocky substrate in the AMEBR; the fraction of rocky substrate is positively correlated with coastline exposure.
  5. The model for soft-bottom communities reached a 52% GOF with the presence of infaunal filter-feeders and epifaunal detritivores depending directly on SST and surface chlorophyll a. The fishery-related variables considered in the model had no apparent effect on the structure of either type of subtidal community.
  6. These results provide a hierarchy of physical–biological associations determining the functional composition of subtidal benthic communities in management areas along central Chile. This knowledge may improve future assessments of ecosystem response to changes in environmental conditions and management strategies.
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The effect of melatonin implants administered during non‐breeding season in Rasa Aragonesa rams on sperm motility parameters and other reproductive traits was assessed. In a first experiment, two Rasa Aragonesa rams were implanted (with melatonin group M), remaining other two males as control group (C). Semen of each group was collected from 1 May to 23 June, twice or three times a week, and motility parameters were assessed using a computer‐assisted sperm analysis system. Melatonin increased the percentage of progressive motile spermatozoa, particularly during 46–75 days after melatonin implantation (p < 0.01). In experiment 2, M and C in vitro fertilization ability had been determined by zona‐pellucida binding assays, using spermatozoa from experiment 1, obtained 60–70 days after melatonin was implanted. A significantly higher number of spermatozoa attached per oocyte was observed in frozen‐thawed immature ovine oocytes incubated with sperm from M animals than in those incubated with sperm from the C group (p < 0.01). Finally, a field assay (experiment 3) was performed. In this case, five Rasa Aragonesa rams were implanted with melatonin and three remained as control group. Sperm doses from those animals were used for artificial insemination of 2608 Rasa Aragonesa ewes from 39 different farms at non‐breeding season. Fertility, litter size and fecundity were studied. Semen from melatonin implanted rams seemed to increase both fertility and fecundity in ewes inseminated with spermatozoa obtained 46–60 days after implantation (p < 0.1). Thus, melatonin treatment in rams during non‐breeding season modifies sperm motility parameters and seems to improve the fertilization parameters obtained.  相似文献   
58.
It was suggested that the cryodamage to oocytes' DNA has been responsible for the compromised developmental competence of cryopreserved oocytes. Vitrification of bovine oocytes affected not only cellular components, but also nuclear material. A significant rate of DNA fragmentation was found in bovine frozen or vitrified oocytes analysed by Comet assay regardless of cryopreservation method. Our method of vitrification using droplet system after gentle pre-equilibration treatment is one of the most effective cryopreservation methods employed for bovine oocytes so far, making it possible to develop 30% blastocyst stage embryos. In this study, the extent of DNA damage in bovine oocytes vitrified using three vitrification methods (droplet system, Open Pulled Straw and traditional vitrification in 0.25 ml insemination straws) was compared using Comet assay. Vitrification in droplet system and Open Pull Straws vitrification did not result in detectable cryoinjuries of DNA of bovine oocytes. On the contrary, DNA fragmentation was found in four of 26 oocytes vitrified in 0.25 ml straws (15.4%, p   ≤ 0.05 in comparison with the other vitrification methods).  相似文献   
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An 8-year-old terrier cross and a 10-year-old German Shorthaired Pointer presented to the University Veterinary Centre, Sydney, for investigation of long-standing tenesmus and dyschezia. Both patients had an annular adenocarcinoma at the colorectal junction. Exploratory laparotomy was performed and the affected large intestinal segment was removed by resection and anastomosis. In both dogs, the caudal mesenteric artery was intimately associated with the mass, necessitating its ligation and transection. Postoperatively, there was no evidence of anastomosis breakdown in either case and both animals recovered well from surgery. The dogs were euthanased 8 and 10 months, respectively, after surgery because of clinical signs relating to metastatic disease.  相似文献   
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