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71.
Over a two year period, postpartum suckled Hereford and Angus Cows (n=213) were administered two injections of PGF(2)alpha (25 mg/injection) and divided into three groups. No additional treatments were administered to cows in Group I and calves were allowed to nurse their dams ad libitum. In Group II, calves were removed for 48 hours beginning on the third day following the initial PGF(2)alpha injection. These cows were given a subcutaneous injection of 250 mug GnRH dissolved in 2% carboxymethylcellulose midway through the 48 hour period. In Group III, calves were allowed to nurse their dams for only one hour per day for the first 7 days after the initial PGF(2)alpha injection. In year 1, PGF(2)alpha was administered 14 days apart whereas in year 2, PGF(2)alpha was administered 11 days apart. Cows were artificially inseminated at 72 and 96 hours after the second injection of PGF(2)alpha. In year 1, the numbers of cows that conceived to the timed inseminations were similar (P > .10) for the three groups. In year 2, a higher percentage of cows in groups II (P < .10) and III (P < .05) conceived to the timed inseminations than in group I. Other reproductive performance parameters were similar (P > .10) between groups for both years 1 and 2. In summary, limited nursing and short term calf removal in conjunction with GnRH treatment may improve the pregnancy rate in cows administered PGF(2)alpha for ovulation control. 相似文献
72.
Maximum likelihood estimation by counting methods under polygenic and mixed models in human pedigrees.
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J Ott 《American journal of human genetics》1979,31(2):161-175
For pedigree data, the maximum likelihood estimates of the parameters in polygenic and mixed models are derived analytically although not in closed form but in terms of "counting equations" allowing an iterative solution. Likelihood computations, tests of significance, and tests of goodness of fit are presented. Accelerating the (linear) rate of convergence by a very simple method is demonstrated. 相似文献
73.
Among a consecutive series of 9,279 sternotomies performed during a period of 2(1/2) years, 61 (0.66%) patients developed significant wound complications. Of these, 58 (95.1%) survived. Sternal infection occurred in 36 patients (0.39%). Predisposing factors included chronic obstructive pulmonary disease, diabetes mellitus, obesity, closed chest massage, prolonged assisted ventilation, and excessive bleeding after operation. Positive end expiratory pressure (PEEP) did not, in itself, predispose to sternal dehiscence. Intermittent positive pressure breathing (IPPB) treatments caused excessive coughing, which may have increased the likelihood of dehiscence. Disposable drapes and expeditious surgery probably contributed to the low incidence of wound infection. Early diagnosis, surgical debridement, rewiring and primary closure with substernal drainage, without continuous antibiotic irrigation, resulted in satisfactory resolution in most patients. 相似文献
74.
Dissatisfaction with the hemodynamic characteristics of available porcine valves prompted a clinical trial of the Ionescu-Shiley percardial xenograft (ISPX) valve. Three hundred fifty-six ISPX valves were implanted consecutively in 326 patients. Operative mortality was 2.6% (2/75) for aortic valve replacement alone and 7.7% (12/155) for aortic valve replacements that included reoperations and combined procedures such as mitral commissurotomy, annuloplasty, and coronary artery bypass. Operative mortality for all patients who underwent mitral valve replacement was 9.5% (14/147). The mean peak systolic gradient pressure in the aortic position was 5.4 mm Hg overall and 4.27 mm Hg with the size 19 mm valve. There were no embolic episodes in patients who received the ISPX valve in the aortic position. The available data indicate that the rate of peripheral embolism with the ISPX valve compares favorably with that of porcine valves. Considering its hemodynamic advantage, if the longterm durability of the full-orifice Ionescu-Shiley pericardial xenograft valve continues to be confirmed by follow-up studies, it is our opinion that it is the biologic valve of choice. 相似文献
75.
Breeding soundness examinations of rams and bucks may be performed by veterinarians as a service for clients. A physical examination for breeding soudness includes a general examination for health with special consideration of the reproductive organs. Careful examination of the penis, prepuce, and testicles may reveal diseases or abnormalities which decrease reproductive potential. Rams with small or hypoplastic testicles are unsatisfactory potential breeders as testicle size is positively related to sperm production. Libido may be assessed during semen collection procedures or from observations of the owner. Semen quality may be evaluated using tests for motility, concentration, and morphology of spermatozoa. Rams may be declared satisfactory, questionable, or unsatisfactory potential breeders as a result of the examination. 相似文献
76.
A 3-year study was conducted on an existing, one-cell, facultative sewage lagoon having a total surface area of 3.6 ha and receiving a BOD5 loading rate of 44 kglhald (40 Iblald). The comparative experimental periods ran from July through November for 3 consecutive years. During the first period, water hyacinths completely covered the lagoon. The water hyacinth coverage was reduced to 33% of the total surface area the second year. The lagoon, free of all vascular aquatic plants the third year, was monitored for comparative purposes. The most significant improvement overall in the effluent quality occurred when water hyacinths covered the entire lagoon. During this period the effluent BOD5 and TSS were 23 and 6 mgll, respectively. Without water hyacinths, the effluent BOD5 and TSS were 52 and 77 mgll, respectively. The effluent total organic carbon concentration with water hyacinths averaged 40 mgll, and without water hyacinths, 72 mgll. A discussion of the results from this 3-year study is presented in this paper along with associated problems that were observed when water hyacinths were introduced into the lagoon and altered its behavior from that of a normal facultative lagoon. 相似文献
77.
In 40 rats immobilized with gallamine evoked field potentials were elicited in the dorsal hippocampus by stimulation of the septal nuclei. Latency of the septohippocampal evoked potential (SHEP) elicited by stimulation of the medial septal nuclei, the variations of latencies and amplitudes with increasing stimulus intensities as well as the occurrence of frequency potentiation and post-tetanic potentiation allow the conclusion that the SHEP registered in the stratum granulare of dentate gyrus is mainly monosynaptically elicited. Nevertheless some data discussed in the paper point to the existence of a more complicated and not exclusively monosynaptic activation of granular cells caused by septal stimulation. 相似文献
78.
Claramma M. Chacko Rebecca S. Wappner Ira K. Brandt Henry L. Nadler 《Human genetics》1977,37(3):261-270
Summary A new variant of clinical galactosemia with two hitherto unidentified alleles on the transferase locus in one family is described. This new clinical variant of transferase has 25% of normal control activity in blood and in skin fibroblasts, and the patient accumulates galactose-1-phosphate in blood on an unrestricted galactose diet. Using starch gel electrophoresis on the hemolysate of the family members, a fast-moving transferase with mobility in between those of the normal control and of the Duarte variant is identified. This new allele is designated as
(fast-moving Chicago variant). In addition, a second new allele was documented in this family by studying the instability of the transferase enzyme in hemolysates of family members at 50°C for various time intervals. This new allele is designated as
(heat-labile Chicago variant). On the basis of the studies, the transferase genotype of this patients is thought to be a double heterozygote compound,
/GALTG. 相似文献
79.
80.
Harvey R. Herschman Dennis S. Passovoy Rebecca M. Pruss Aharon Aharonov 《Journal of cellular biochemistry》1978,8(3):263-268
The growth-promoting activities of fetal bovine serum, cortisol, phorbol myristate acetate, prostaglandin F2α, insulin, epidermal growth factor, and fibroblast growth factor were evaluated on four murine embryo cell lines (Swiss 3T3, Balb 3T3, M2, and C3H10T1/2). Each cell had an unique response spectrum to this collection of reported mitogens. Phorbol myristate acetate and prostaglandin F2α were active only on selected cell lines; cortisol was inactive on all four lines. Serum, epidermal growth factor, and fibroblast growth factor were able to stimulate cell division in all four lines, albeit to varying degrees for the different target cells. 相似文献