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101.
The rate of disappearance of levamisole in milk from cows given levamisole hydrochloride drench, levamisole resinate in feed pellets, levamisole hydrochloride boluses, or levamisole phosphate injectable was determined. Each formulation was given as a single treatment to each of five cows at a rate equivalent to 8 mg of levamisole hydrochloride/kg of body weight. Levamisole hydrochloride residues in milk averaged .50, .55, .58, and .32 ppm at 12 hr after the administration of levamisole drench, feed, bolus, and injectable formulations. Levamisole hydrochloride residues were below .01 ppm in milk at 48 h after drench treatment and at 60 h after treatment with other three formulations. Toxicity symptoms were not observed in any cows following treatment.  相似文献   
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Success in the use of custom-fabricated Silastic implants in patients with facial contour defects led us to utilize this method in reconstructing mandibular defects. However, mandibular reconstruction with alloplastic material is quite difficult because of the presence of continous stress and motion in that region. The evolution in the use in the use of the mandibular implant from the commercially available one to the K-wire reinforced, prefabricated, silicone implant was largely dependent on the availability of silicone and the ultimate result obtained. In the past few years, about 30 subdermal implants were inserted. Some of those implants were placed immediately into patients undergoing resection for tumor. The implant was prefabricated prior to surgery from x-ray measurements of the anticipated segment to be resected; it was then used to reconstruct the defect prior to the final closure of the operative wound. Other implants were manufactured 6-18 months after resection for tumor or for deformity as a result of trauma. The implants were used to reconstruct the facial defects and to correct the funtional abnormality, such as drooling or deviation of the affected side by the unstable mandibular segment. Patients with severe congenital malformation have soft tissue deficiency in association with their bony malformation. Therefore, implants in such conditions were doomed to failure. Patient selection is the key to successful implantation.  相似文献   
104.
Addition of amethopterin to medium before inoculation inhibited DNA synthesis and induced microcycle sporogenesis in Bacillus brevis spp. AG4. Synthesis of RNA and proteins occurred at a considerably reduced rate.  相似文献   
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Angiotensin converting enzyme (ACE) and leucine aminopeptidase (LAP) regulate fetally and maternally generated peptides in the placenta. In this study, ACE-like activity was found to be decreased and LAP-like activity increased with increasing days of gestation in rat placental tissues forming the fetal:maternal interface. Membrane-associated ACE-like and LAP-like activities in the placenta of smokers were also found to be significantly higher than their respective activities in placenta of nonsmokers. Our collective findings suggest that gestational and environmentally-induced changes in placental peptidase activities may account for variable peptide hormone and/or therapeutic peptide metabolism in the placenta.  相似文献   
107.
Zinc levels in seminal plasma were measured. The study was done on 122, random selected males from infertile couples. The atomic absorption spectrophotometer was used. Sperm density of ejaculate was also determined. These parameters were compared in subgroups: normospermic and oligospermic and in classes of variable oligospermic severity. Semen serum zinc levels in normospermic men was significantly increased as compared to oligospermic men. There were no significant differences in zinc levels between the different classes of oligospermia.  相似文献   
108.
Researchers investigated the effects of three different previewing interventions on the oral reading rates of 12 junior and senior high school students with learning disabilities. Under fast-rate listening previewing (FRLP), students were instructed to follow silently as experimenters read from a text at an average rate that was 77.7% faster than the students' current oral reading rate. During slow-rate listening previewing (SRLP), students followed along as experimenters read at an average rate that was 22.5% faster than the students' reading rate. Students were instructed to read passages silently under silent previewing (SP). Immediately following each previewing intervention, students read the same passage aloud. The number of words read correctly per minute and the number of errors per minute served as dependent variables. The results showed statistically significant decreases in error rates under SRLP and SP. The results also showed that SRLP resulted in statistically significantly fewer errors per minute than FRLP. These results suggest that orally reading while students follow along at a rate much higher than their current reading rates may not be as beneficial as reading aloud at slower rates.  相似文献   
109.
This study aimed to evaluate intake, body growth, and the development of the rumen, mammary gland, and immune system in Holstein Friesian calves reared for 100 d on the commercially available feed FiberStart (conserved alfalfa, Medicago sativa; Fiber Fresh Feeds Ltd., Reporoa, New Zealand) and fed calf milk replacer (CMR) for either 56 or 91 d. Eighty calves (40 bulls and 40 heifer calves) were reared indoors in groups (n = 5 of the same sex/pen). All calves were fed 4 L of CMR/d (175 g/L of CMR) in 2 feeds/d for the first 10 d and then 1 feed/d until d 49 or 84. The calves were gradually weaned by d 56 (earlier weaned; n = 8 pens) and d 91 (later weaned; n = 8 pens). All calves were fed FiberStart ad libitum as the only solid feed source from d 1 to 100 of the study. Irrespective of treatment, all calves had similar body weights at d 0 (40.9 ± 3.0 kg) and d 49 (74.2 ± 5.1 kg) of the study. Calf sex had no effect on intake, growth, blood, and immune system parameters. Earlier-weaned calves consumed 18% more solid feed dry matter but had 16% lower body weight gain (28.9 vs. 38.5 kg, respectively) from d 56 to 100 relative to later-weaned calves, resulting in different body weight at 100 d (104 vs. 121 ± 1.3 kg). Although earlier-weaned calves could compensate for the loss of CMR dry matter and crude protein intake from d 56 to 100 by increasing forage intake, they were unable to compensate for the loss of energy from the CMR by increasing solid feed consumption. Plasma β-hydroxybutyrate concentrations were 52% greater in earlier-weaned calves than in later-weaned calves at d 84, indicating greater metabolic activity of the rumen wall. The duration of CMR feeding had no influence on humoral or cell-mediated immune functions of the calves, as evidenced by a lack of effect on antivaccine antibody responses as well as on immune gene expression. Earlier- versus later-weaned heifer calves had 5% lower mammary gland mass, indicating that greater energy supply increased mammary mass. The results of this experiment demonstrate the ability to artificially rear dairy calves on a conserved alfalfa as the only solid feed. Furthermore, earlier weaning off CMR promotes solid feed intake and an associated increase in blood β-hydroxybutyrate, an indicator of rumen development, but increasing the duration of CMR feeding improves growth and mammary gland mass by d 100. The implications of these findings on lifetime growth, health, and milk production in dairy heifers warrant further investigation.  相似文献   
110.
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