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1.
The aim of this experiment was to investigate the effects of dietary protein and energy on ovulation rate and embryo survival to day 8 of pregnancy, and the associated concentrations of progesterone in jugular, ovarian and uterine veins, in a Spanish breed of sheep. In mid-October, three groups of ewes were fed to provide 1.5 x (H; n = 9), 0.5 x (L; n = 12) or 0.5 x plus 7.44 g CP/MJ ME (LP; n = 8) energy requirements for maintenance of live weight from day -14 relative to a synchronized mating on day 0. A significant effect of nutrition on ovulation rate was observed (H: 2.22 +/- 0.16; L: 1.50 +/- 0.16; LP: 1.88 +/- 0.12 corpora lutea; P < 0.05). Mean LH and progesterone concentrations were affected by nutrition on day 7, L ewes showing the highest mean LH level (P < 0.01), while H ewes presented the lowest mean LH concentration and the highest mean plasma progesterone concentration (P < 0.01). Laparotomies were performed on six animals of each group on day 8 to determine the effect of nutrition on embryo development. A significantly higher percentage of embryos recovered from L and LP ewes presented an earlier stage of development (morulae or early blastocysts) (P < 0.001), while 100% embryos of H ewes were expanded blastocysts. The ratio expanded blastocysts/corpora lutea was significantly higher in H ewes (0.86) when compared with L and LP groups together (0.57; P < 0.05). Mean progesterone concentration in the ovarian vein was 800-fold higher than mean jugular venous levels with no differences between groups. Samples from ovarian veins contralateral to corpus luteum-bearing ovaries showed mean progesterone concentrations significantly lower than samples opposite to corpus luteum (ipsilateral: 1037.84 +/- 138.45; contralateral: 30.4 +/- 11.22 ng/ml; P < 0.001). Mean progesterone concentration in the uterine vein was approximately 30-fold higher than in jugular and similar in both uterine horns and treatments. No effect of nutrition on pregnancy rate was observed (H: 89%; L: 92%; LP: 100%). These results suggest that neither dietary energy nor protein are able to modify pregnancy rate or progesterone concentrations in ovarian and uterine veins eight days after mating. However, the delay in embryo development observed in the embryos collected from L and LP ewes may give rise to compromised embryo growth and development some days later.  相似文献   

2.
Growth of a mixed ruminal population taken from a sheep on a protein-free (all urea) purified diet was estimated by an in vitro fermentation technique including precipitation of microbial protein by trichloracetic acid. Volatile fatty acid production in vitro was determined, and the associated a denosine triphosphate was estimated as moles volatile fatty acids X 2.4. On this basis, the quantity of microbial protein synthesized per mole of adenosine triphosphate increased at higher microbial growth rates.  相似文献   

3.
The effect of Acetylsalicylic Acid (ASA, Aspirin) on the myocardial production of the inducible form of nitric oxide synthase (iNOS) and the oxidation products of nitric oxide (nitrite, NO-2 and nitrate, NO-3: NOx) were studied in the rabbit heart two days after ligation of a branch of the left circumflex coronary artery. ASA was administered intravenously as AspisolR, DL-Lysinmono(acetylsalicylate) which is soluble in water. Animals received a total dose of 250, 375, or 500 mg/kg of ASA in five divided doses intravenously. Significant inhibition of iNOS was noted in the infarcted portion of the myocardium at 375 and 500 mg/kg of ASA. The reduction in myocardial nitric oxide (NO) production was paralleled by a diminution in coronary arterial-venous difference of NOx, demonstrating that ASA inhibition extended also to the oxidation products of NO. ASA is an inhibitor of cyclooxygenase (COX). The inhibition of iNOS by ASA demonstrates the close relationship between COX and iNOS activity in the heart in situ. Whether activity of the infarcted heart is influenced by the diminution in the production of NO by ASA is not known.  相似文献   

4.
Effects of nitrate ions, nitrous acid, sulfur dioxide, and ferric ions on the corrosion of mild steel in unstirred, concentrated sulfuric acid were determined in laboratory tests. Nitrate and nitrous acid at levels up to 1000 ppm accelerate corrosion. At concentrations greater than 1000 ppm nitrate passivates the steel. Sulfur dioxide and ferric ions have no detectable influence on the corrosion. Reaction mechanisms are presented to explain the observed effects. The impact of nitrogen oxides on the storage and handling of sulfide smelter by-product acid is discussed.  相似文献   

5.
An experiment with a multiple Latin square design using 36 midlactation Friesian cows was carried out to determine the effect of fish meal or soybean meal in a supplement fed at two amounts (3.5 or 7 kg/d) with grass silage. The diets were also fed to four ruminally and duodenally cannulated cows to determine digestibility, ruminal fermentation, and nutrient flows. Dry matter intake, milk production, milk constituent yields, and concentrations of protein and lactose were significantly increased by the supplements when provided at 7 kg/d. The supplement containing fish meal increased milk production, protein and lactose yields, and milk protein concentration, but the increases were smaller than those obtained by increasing the amount of supplement fed. Neither the type nor the amount of supplement fed affected digestibility of dry matter or organic matter, and few significant effects on ruminal fermentation were observed. Supplements fed at the higher allowance significantly increased the flow of dry matter, organic matter, all nitrogenous components, and amino acids to the duodenum. The supplement containing fish meal significantly increased the duodenal flow of nonammonia nonmicrobial N and some amino acids. Results indicated that an increase in the concentration of supplement in the diet is more effective in increasing milk production, protein concentration and yield, and flow of amino acids to the duodenum than is increasing the concentration of ruminally undegradable protein in the supplement.  相似文献   

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Chronic haloperidol treatment caused significant decreases in the levels of synaptotagmin I and IV, synaptobrevin II, syntaxin 1A and Rab 3A mRNAs in the nucleus accumbens but not in the prefrontal cortex medial field, striatum, substantia nigra and ventral tegmental area. No significant changes in SNAP 25 and synaptophysin mRNA levels were observed in any brain region examined. The reduced expression of synaptic proteins may be related to haloperidol-induced depolarization block of mesolimbic dopamine neurons.  相似文献   

8.
We used the [15N]glycine single-dose urea end-product technique to measure whole-body protein turnover in six Holstein steers (250 +/- 18 kg). Steers were implanted with Revalor-S and continuously infused abomasally with water (4 L/d) or amino acids (AA; in 4 L/d water) in a crossover experiment (two 14-d periods). The AA infusion contained the following (g/d): lysine (5.3), methionine (3.3), threonine (3.2), tryptophan (1.0), histidine (2.1), and arginine (5.5). Steers were fed a diet containing 85% rolled corn, 10% prairie hay, and 1.1% urea (DM basis) at 2.16% of body weight. Nitrogen retention tended (P = .15) to increase with AA infusion, from 27.9 to 32.9 g N/d. Amino acid infusion numerically increased whole-body protein turnover from 168.6 to 183.2 g N/d, protein synthesis from 152.6 to 169.3 g N/ d, and protein degradation from 124.7 to 136.4 g N/d. Enhanced protein accretion may have resulted from a larger increase in protein synthesis than in degradation. The tendency for increased N retention is interpreted to suggest that the implanted, lightweight Holstein steers fed a corn-urea diet in our study were able to respond to AA supplementation, suggesting that at least one of the infused AA was limiting in the basal diet. Protein turnover data suggest that cattle, like other animals, may increase protein synthesis and protein degradation in response to supplementation with limiting AA. The [15N]glycine single-dose urea end-product technique for measuring whole-body protein turnover in cattle may be useful.  相似文献   

9.
The present experiments were undertaken to investigate the effects of environmental temperatures on growth, abdominal fat content, rate of muscle protein turnover, and heat production in tube-fed intact male broiler chickens. Plasma concentrations of thyroxine (T4), triiodothyronine (T3), and corticosterone (CTC) were also examined. Chicks (15 d old) were kept at different environmental temperatures (16, 19, 22, 25, 28, 31, and 34 degrees) and given the experimental diet (200 g crude protein/ kg, 13.57 MJ/kg metabolizable energy) by tube three times daily throughout the 12 d experimental period. In the hot conditions, except for 34 degrees, body-weight gain was significantly higher than in the cold conditions. Thus, food conversion ratios (food:gain ratios) were lower when the birds were exposed to the hot conditions other than 34 degrees. Likewise, abdominal fat content was significantly increased, and heat production was lower in the groups kept under the hot conditions other than 34 degrees. The rate of skeletal muscle protein turnover and plasma concentration of CTC were decreased when the birds were exposed to hot conditions other than 34 degrees, suggesting a role of CTC in the regulation of muscle protein turnover. Plasma concentrations of T4 and T3 were significantly decreased as environmental temperature increased. These results clearly show that plasma concentrations of thyroid hormones and CTC are associated with accelerated muscle protein turnover and heat production.  相似文献   

10.
Cannulated steers were used to determine the effects of supplemental soybean meal, heated soybean meal, fish meal, and a combination of fish meal, heated soybean meal, and corn gluten meal on intraruminal protein degradation and absorption of AA from the small intestine. Organic matter digestion in the reticulo-rumen was greater in steers fed diets supplemented with soybean meal, but whole tract digestibility was not affected by protein source. Total and bacterial CP flows to the abomasum were lower in steers fed diets supplemented with fish meal than in steers fed diets supplemented with heated soybean meal or the combination supplement. Dietary CP flow was 33.5% higher in steers fed diets supplemented with heated soybean meal than in steers fed diets supplemented with soybean meal, fish meal, or the combination supplement. Less essential and nonessential AA flowed to the abomasum and were absorbed from the small intestine of steers receiving diets supplemented with soybean meal. Digestibility of small intestine AA was 21.9% lower in steers receiving the soybean meal treatment. Abomasal flows of Met and Thr and absorption of Lys, Met, and Thr were increased in steers fed diets containing heated soybean meal, fish meal, and the combination supplement. These results suggest that the supply of AA deficient in microbial CP (Lys, Met, and Thr) can be increased and that absorbed AA balance can be changed markedly by selection of rumen escape protein supplements.  相似文献   

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13.
All available beta-blockers are effective in the treatment of high blood pressure. Differences in the pharmacokinetics are important as they can have an impact on their clinical use. Betaxolol, a beta-1-selective blocker has a long biological half-life which can control the blood pressure and pulse rate for 24 hours. The authors investigated 20 patients with mild and medium severe hypertension by out-patient monitoring of the blood pressure. Treatment was focused on influencing the morning rise of blood pressure and pulse rate. The results confirm the effectiveness of betaxolol (Lokren) in the administered dose of 10-20 mg once per day. A favourable response was obtained in 75% when checked by a sphygmomanometer. The morning readings of blood pressure at 5, 6 and 7 o'clock following treatment did not exceed 90 mmHg diastolic pressure. It was also found that there is a statistically significant difference in the effect exerted on pressure and pulse rate in daytime, while the difference at nighttime is not significant. This mild reduction on blood pressure and pulse rate during the night is an advantage in particular in elderly patients. Lokren treatment did not have any serious side-effects it did not affect laboratory values or ECG with the exception of the pulse rate.  相似文献   

14.
Erythrocyte C3b receptors (E-CR1) were assayed by ELISA in 16 patients with acute viral hepatitis. In 13 patients with hepatitis type A, type B, or type non-A non-B, the E-CR1 level was significantly lower in the acute phase than in healthy controls, and recovered in the convalescent phase. The E-CR1 levels in 3 patients with non-A, non-B hepatitis remained below the mean level of the healthy controls. These findings suggest that the E-CR1 level fluctuates in acute viral hepatitis, and that it continues to be reduced in some patients with non-A non-B acute hepatitis.  相似文献   

15.
We report the histological, immunohistochemical and ultrastructural findings of an exophytic cutaneous tumor composed of a mixture of typical basal cell carcinoma (BCC) and malignant fibrous histiocytoma. Nine previously reported carcinosarcomas of the skin are reviewed. We prefer the term "sarcomatoid carcinoma" for this rare neoplasm. Only the BCC showed a positive immunoreaction to cytokeratin; the sarcomatous component was negative, but it did express vimentin, and, focally, smooth-muscle-specific actin and KP1 (CD68). Both components showed p53 immunostaining.  相似文献   

16.
Fourteen isolates of Treponema hyodysenteriae and 11 isolates of T innocens from eight different countries were evaluated in the CF1 strain female mouse for virulence. Mice were fasted for 24 hours and inoculated intragastrically with 1 ml of culture for two consecutive days. Mice were killed and necropsied at 12 to 15 days after inoculation. Caecitis was detected in mice from each of the groups receiving T hyodysenteriae (67 per cent) but not in mice receiving T innocens or sterile broth. Lesions consisted of hyperaemia, mucosal oedema, catarrhal inflammation and occasional haemorrhage. These studies suggest that the CF1 mouse may be an inexpensive in vivo means of differentiating T hyodysenteriae from T innocens.  相似文献   

17.
The effect of the thyroid hormone on the rate of brain protein synthesis in rats was studied. Experiments were conducted on three groups of rats given 6-propyl-2-thiouracil (PTU, a thyroid inhibitor) without a triiodothyronine (T3) treatment, those treated with PTU + T3, and those treated with neither PTU nor T3 (control). The fractional rates of protein synthesis in the brain, liver, and kidney of rats given PTU + T3 were significantly greater than those in rats given PTU alone. In the brain and kidney, the RNA activity [g of protein synthesized/(g of RNA.d)] were significantly correlated with the fractional rates of protein synthesis. In the liver and kidney, the RNA concentration (mg of RNA/g of protein) was related to the fractional rate of protein synthesis. These results suggest that the thyroid hormone treatment would be likely to increase the rate of protein synthesis in the brain of rats, and that the RNA activity is, at least partly, related to the fractional rate of brain protein synthesis.  相似文献   

18.
Evaluation of 12-month results of photorefractive keratectomies (PRK) performed in low myopic (0 to -6.0 D) and low hyperopic (0 to +6.0 D) eyes. Myopic and hyperopic PRK treatments with the Aesculap Meditec MEL 60 ArF excimer laser. Prospective study, 30 eyes per group. The change in best corrected visual acuity (VA), refraction required, uncorrected VA and the postoperative haze were compared at the 12th postoperative month. The average preoperative correction in the low myopic eyes (Group I) was -4.65 +/- 1.24 D, which decreased to -0.17 +/- 0.56 D during the follow-up. In mild hyperopic eyes (Group II) the preoperative refraction was +3.9 +/- 0.93 D and decreased to +1.23 +/- 1.59 D post-PRK. Comparing the pre- and postoperative average best corrected VA values, there was no statistical change in either group. In the low myopic group all eyes had a 20/40 or better uncorrected VA, in hyperopic eyes 11 had a VA of 20/40 or better, four had a worse uncorrected VA. In Group I, 86.6% of the eyes were within +/-1.0 D of the intended refraction at 12 months postoperatively. In Group II, 46.7% of the eyes were within +/-1.0 D of final refraction. There were no intergroup differences in subjective complaints, reepithelization and average postoperative haze. Both methods are able to alter the refractive power of the cornea toward emmetropia. The predictability of the method was to be found higher in cases of mild myopia than in mild hyperopia. The upper limit of myopia is above -6.0 D, but in hyperopia, with the present technical facilities, good postoperative results can be obtained only as far as +4.25 D of preoperative refractive error.  相似文献   

19.
In male rats, noncontact erections occur concomitantly with an increase in NO?- and NO?- in the paraventricular nucleus of the hypothalamus (PVN). In the present study, both responses were reduced by the blockade of PVN excitatory amino acid receptors by dizocilpine, (+)-MK-801(1 and 5 μg), but not by 6-cyano-7-nitro-quinoxaline-2,3-dione (5 μg) or (±)-2-amino-4-phosphono-butanoic acid (5 μg). Also ineffective when injected into the PVN were the dopamine antagonists SCH 23390 (5 μg), S(+)-raclopride (10 μg), and cis-flupenthixol (10 μg), and the oxytocin antagonist d(CH?)?Tyr(Me)2-Orn?-vasotocin (1 μg). However, when the last was given into the lateral ventricles, it reduced noncontact erections without modifying NO?- and NO?- increases. These results suggest that excitatory amino acid transmission increases in the PVN during noncontact erections. This may contribute to increased NO production in the PVN, and it may activate oxytocin neurons mediating this sexual response. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

20.
Spinal muscular atrophy (SMA) is a motor neuron disorder resulting from anterior horn cell death. Survival motor neuron ( SMN ) is the SMA-determining gene and is deleted or gene converted in >95% of SMA patients. The SMN protein has a role in spliceosomal snRNP biogenesis and has therefore been implicated indirectly in general cellular RNA processing due to its unique sub-nuclear localization within structures termed 'gems', which co-localize with spliceosomal factors within coiled bodies. In this report, direct SMN RNA-binding activity, in addition to ssDNA and dsDNA binding is demonstrated. The region of SMN encoded by exon 2 is necessary and sufficient to mediate its nucleic acid-binding activities. This domain is homologous to several nucleic acid-binding factors, including several high mobility group (HMG) proteins. Additionally, previously reported SMN missense mutations isolated from SMA patients demonstrated reduced RNA-binding activity, suggesting that nucleic acid binding is functionally significant.  相似文献   

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