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131.
Linking long-term dietary patterns with gut microbial enterotypes   总被引:1,自引:0,他引:1  
Diet strongly affects human health, partly by modulating gut microbiome composition. We used diet inventories and 16S rDNA sequencing to characterize fecal samples from 98 individuals. Fecal communities clustered into enterotypes distinguished primarily by levels of Bacteroides and Prevotella. Enterotypes were strongly associated with long-term diets, particularly protein and animal fat (Bacteroides) versus carbohydrates (Prevotella). A controlled-feeding study of 10 subjects showed that microbiome composition changed detectably within 24 hours of initiating a high-fat/low-fiber or low-fat/high-fiber diet, but that enterotype identity remained stable during the 10-day study. Thus, alternative enterotype states are associated with long-term diet.  相似文献   
132.
Patellar fixation is a common cause of lameness in horses and has been successfully treated by injection of the patellar ligaments with counterirritants. To investigate the effects of this treatment, the medial and middle patellar ligaments of 10 ponies were injected with an oil-based iodine counterirritant solution and then examined morphologically. Vacuoles of counterirritant were present in the paratenon and endotenon of the ligaments and caused severe necrosis and inflammation. At 1 day after injection, there was a marked neutrophilic infiltration which progressed to a lymphocytic infiltrate by 3 days. By 7 days, fibroplasia was present and became more organized with time. Disrupted collagen fibers and numerous, large, pale fibroblasts were present in the fasciculi, but neutrophilic infiltration was absent. The fibrous response in the fasciculi was similar to that present in the paratenon and endotenon. At 28 days, the drug was still present as lipid vacuoles in the paratenon and endotenon, and the damaged fasciculi had not regained their normal appearance. The clinical effect of this treatment was attributed to the change in size and shape of the patellar ligaments resulting from the inflammatory response.  相似文献   
133.
ACUTE LAMINITIS has long been attributed to factors or events that precede the onset of laminitis. Between 1759 and 1907 the overconsumption of grain, inflammation of the feet, suppression of perspiration (anhydrosis), excessive rest, excessive bleeding, road concussion, poor shoeing, unilateral weight bearing, sudden environmental temperature changes, prolonged standing (in the cold and aboard ships), diarrhea, and postpartum complications were all designated as causes. Today, commonly listed etiologic factors include ingestion of large amounts of grain, cold water, lush grass, or black walnut shavings, repeated concussion, endometritis or other severe infections, colic, exhaustion, stress, drug toxicities, and endocrine dysfunctions. At Texas A&M University (Table 1) the factors recorded as the cause presume a causal relationship between some preceding event and the acute laminitis. Logically, any event that precedes laminitis might be a cause, but etiologic validity depends on the definition of "cause" and the role that coincidence might have in the appearance of the disease.  相似文献   
134.
Preparations of the herb, goldenseal, have been used in an attempt to thwart detection of morphine in urine of human addicts and racing horses. To assess the potential of goldenseal to interfere with equine drug detection, horses were dosed with morphine (0.1 mg/kg IV) and, in one experimental series, also with goldenseal (60 mg/kg, p.o.). Goldenseal resulted in significant increases in urine volume, specific gravity and acidity. A significant decrease in total morphine excreted occurred 5–6 hours after dosing. It was concluded that with inclusion of an efficient hydrolysis step in the analysis, goldenseal was unlikely to interfere with urine tests for morphine, even if water loading was included in the dosing regimen.  相似文献   
135.
The ability of an immunomodulator, mycobacterial cell wall extract (MCWE), to clear uterine infection in susceptible mares after an experimental challenge withStreptococcus zooepidemicus was evaluated. Thirty mares susceptible to endometritis, based on the presence of uterine fluid during both diestrus and estrus, were selected from a herd of 896 and inoculated with a live culture of 5 × 106 CFU of S. zooepidemicus on day 1 of estrus. Twenty-four hours later, mares were evaluated by ultrasonography, bacteriology, exfoliative cytology, and uterine biopsy to confirm infection. Forty-eight hours after inoculation, and on confirmation of uterine infection, mares were randomly assigned to one of four unbalanced experimental treatments to receive 1500 μg MCWE IU (n = 10) or IV (n = 10), or placebo IU (n = 5) or IV (n = 5). Mares were examined at ovulation and 7 days post-ovulation for uterine fluid via transrectal ultrasonography and for bacteriology, exfoliative cytology, and uterine biopsy. Efficacy was based on the ability of the mare to clear endometritis as determined by negative bacteriology and reduced numbers of polymorphonuclear cells (PMNs) on uterine biopsy. Because no statistical difference was detected between routes of administration on day 7 post-ovulation, the data sets were combined and re-analyzed to evaluate overall efficacy. Endometritis was observed in all placebo-treated mares 7 days post-ovulation, whereas treatment with MCWE resulted in the elimination of endometritis in 35% of the mares by the time of ovulation, and 70% of the mares by 7 days post-ovulation. Treatment with MCWE, compared with the placebo group, resulted in a significant decrease in the number of mares positive for endometritis at ovulation based on exfoliative cytology and bacteriology (P < .01) and at 7 days post-ovulation based on biopsy, exfoliative cytology, and bacteriology (P < .001). Results indicate that MCWE was an effective treatment for the elimination of endometritis caused by S. zooepidemicus in mares.  相似文献   
136.
Summary Two separate experiments were conducted in which sunflower lines were tested for their pollen production and hybridization performance.In the first experiment, lines derived from a common source were tested for their pollen production. In the second experiment, two standard varieties were tested for their combining ability.The tested lines differed significantly in their pollen production. It was further shown by correlation analysis that these differences were maintained over two seasons. It is concluded that the technique developed in the investigations can be used to advantage in selecting male and female parents in the breeding program.Experiments on mixed seed rates of two standard varieties failed to give yield data, and consequently, no definite conclusions may be drawn.Agriculture and industry are just beginning to recognize the sunflower as an important source of oil and other substances. Since this crop has not been intensively studied, future investigators should be quite effective in advancing its relative importance, both as to production and utilization.  相似文献   
137.
Conclusion The protest against Michurinism, from non-Russian countries, has been on three main grounds: that his scientific theories are unconvincing; that the intrusion of political influence into scientific controversy is unjustifiable; and that the treatment meted out to his defeated opponents has included imprisonment and death.Modern genetics has grown through the work ofCorrens, Goldschmidt, Muller, Darlington, Haldane and many others, and today many aspects of it are thoroughly permeated with physiological and dynamic thinking.Lysenko, however, still attacks it on the old lines, using arguments form the pregenetical days ofDarwin as well as those produced byMichurin, Timirtazey, etc. who first criticized it. Lysenko's claim that heredity can be altered by external influences either by submitting the organism to altered conditions, or by grafting one type of plant to another, when the stock and graft are said to influence each other's hereditary qualities, may be looked upon as a scientific novelty.Neither of these two parts is easy to accept.Graft hybridization is a problem with a long history. Nearly all alleged cases in the past have turned out to be misinterpretations; but there is no doubt that viruses and some proteins can be transmitted in this way and act and cause the observed results. It is possible though not yet acceptable as proven, thatLysenko is on to something in this obscure and not fully understood field. But even if this be so, there seems no reason whatever to believe that this results could overthrow classical genetics, though he might conceivably represent an addition, even quite an important addition, to it.Thus it becomes clear that the gap between Michurinites and Neo-Mendelists does not appear to be absolute, and may be further narrowed as reliable evidence becomes more readily available to both groups.  相似文献   
138.
Summary In view of a preliminary investigation of liquid-solid extraction by means of Ultra-sonic waves, the effects of 300, 500 and 2000 kHz insonation was tried, using 50° alcohol and vanilla beans.The experimental results were calculated on a 12 hours extraction base, with a 250 ml Kumagawa.Our experiments have shown that an extraction efficiency of 94%, after 12 min. insonation, can be obtained, but that this efficiency seemed, in our particular case, to be closely correlated with the moisture content of the sample.Besides, the classical extraction in a Kumagawa showed, that such acquired caracters, as increased percentage in vanillin and oleoresines obtained after an ultrasonic irradiation remained stable.
Zusammenfassung Ein Versuch wurde angestellt, Vanille-Extraktion mit Hilfe von Ultraschallwellen durchzuführen.Frequenzen von 300, 500 und 2000 kHz mit Intensitäten von 3,4–13 W/cm2 und Extraktionsdauer, von 3–12 Min., wurden dazu verwendet.Die erzielten Ergebnisse haben deutlich gezeigt, dass unter günstigen Versuchsbedingungen, nach 12 min. Beschallung 94% einer klassischen Extraktion von 12 Stunden mit dem Apparat nachKumagawa, erzielt werden kann.Es scheint jedoch, dass in diesem besonderen Falle die Wirksamkeit der Extraktion vom Feuchtigkeitsgehalt des Vanillenmusters abhängt.Von grossem Interesse ist der Befund, dass der erhöhte Vanillinund Oelsubstanzen-(Oleoresine) Gehalt, der beschallten Vanille-schoten, stabil ist.Hiermit werden neue und interessante Entwicklungsmöglichkeiten dieser neuen Wissenschaft in der Zukunft eröffnet.
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