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121.
ER Smith GM Pesti RI Bakalli GO Ware JF Menten 《Canadian Metallurgical Quarterly》1998,77(11):1678-1687
An experiment was conducted to quantify genetic differences in response to dietary protein level of male vs female broilers. Broilers (1 d old) from a "high-yield" strain cross (Ross x Ross 208) and a "fast-growing" strain cross (Peterson x Arbor Acres) were placed on fresh pine shavings in floor pens. From Day 0 to 18, all birds were fed a 23% CP starter diet. During Days 18 to 53 male birds were fed either a 16, 18, 20, 22, 24, or 26% CP diet (3,200 kcal ME/kg) and female birds were fed the 16, 20, or 24% CP diet. Significant differences (P < 0.05) were noted in the performance of the different strains. Ross x Ross 208 male birds had a higher body weight (3.37 vs 3.16 kg), higher feed intake (7.08 vs 6.78 kg), higher breast yield (31.76 vs 29.25%), higher carcass yield (73.90 vs 71.85%), and a lower adjusted feed conversion ratio (FCR; 2.10 vs 2.16 g:g) than Peterson x Arbor Acres males at 53 d of age. As compared to Peterson x Arbor Acres females, Ross x Ross 208 female broilers also had a higher body weight (2.68 vs 2.55 kg), higher breast meat yield (33.61 vs 30.80%), higher carcass yield (75.31 vs 73.91%), and lower adjusted FCR (1.97 vs 2.04 g:g). Qualitative differences in the response of these strains were confirmed and better qualitative data is presented that can be used to predict the important output parameters from the import inputs in broiler production. 相似文献
122.
AJ Bogdanove JF Kim Z Wei P Kolchinsky AO Charkowski AK Conlin A Collmer SV Beer 《Canadian Metallurgical Quarterly》1998,95(3):1325-1330
The "disease-specific" (dsp) region next to the hrp gene cluster of Erwinia amylovora is required for pathogenicity but not for elicitation of the hypersensitive reaction. A 6.6-kb apparent operon, dspEF, was found responsible for this phenotype. The operon contains genes dspE and dspF and is positively regulated by hrpL. A BLAST search revealed similarity in the dspE gene to a partial sequence of the avrE locus of Pseudomonas syringae pathovar tomato. The entire avrE locus was sequenced. Homologs of dspE and dspF were found in juxtaposed operons and were designated avrE and avrF. Introduced on a plasmid, the dspEF locus rendered P. syringae pv. glycinea race 4 avirulent on soybean. An E. amylovora dspE mutant, however, elicited a hypersensitive reaction in soybean. The avrE locus in trans restored pathogenicity to dspE strains of E. amylovora, although restored strains were low in virulence. DspE and AvrE are large (198 kDa and 195 kDa) and hydrophilic. DspF and AvrF are small (16 kDa and 14 kDa) and acidic with predicted amphipathic alpha helices in their C termini; they resemble chaperones for virulence factors secreted by type III secretion systems of animal pathogens. 相似文献
123.
SH Selesnick MT Abraham JF Carew 《Canadian Metallurgical Quarterly》1996,17(5):793-805; discussion 806-9
Anterior rerouting of the intratemporal facial nerve in the infratemporal fossa approach is employed to access to the jugular bulb, hypotympanum, and lateral skull base, whereas posterior rerouting of the facial nerve, as employed in the transcochlear craniotomy, is most frequently used for surgery of the posterior fossa, cerebellopontine angle, prepontine region, and petrous apex. Facial nerve rerouting may lead to facial paresis or paralysis. This review of the literature is intended to define the physiologic "cost" of these procedures, so that the neurotologic surgeon can determine if the morbidity incurred in these techniques is worth the resultant exposure. Inconsistencies in reporting facial function places into question the validity of some of the cumulative data reported. Postoperatively, grades I-II facial nerve function was seen in 91% of patients undergoing short anterior rerouting, 74% of patients undergoing long anterior rerouting, and 26% of patients undergoing posterior complete rerouting. Although facial nerve rerouting allows unhindered exposure to previously inaccessible regions, it is achieved at the cost of facial nerve function. Facial nerve dysfunction increases with the length of facial nerve rerouted. 相似文献
124.
Entering the field in qualitative field research: a rite of passage into a complex practice world 下载免费PDF全文
The concept of ‘the field’ is significant in ethnographic research as well as qualitative research methods more generally. However, how a field researcher enters the field is usually taken for granted after gaining access to the field. We suggest that entrance is a distinct phase of fieldwork that differs from negotiating access. Entrance is not a trivial event; rather, it is a rite of passage into a complex practice world and marks a critical field moment. Drawing on our ethnography and insights from hermeneutics and anthropology, we show that a practical understanding of the field represents a fusion of horizons where a fieldworker is thrown. The concept of thrownness highlights the fact that the fieldworkers' own historicity and prejudices affect their entrance into the field; hence, entrance into the field orientates an ethnographer in the field and influences the entire period of fieldwork that follows. Our theorizing is intended as a contribution towards advancing the discussion of qualitative research methods. 相似文献
125.
The syndrome of parainfectious encephalomyelitis evolves from an antecedent infection. Several etiologic agents have been associated with this complication, although the pathogenesis in each instance may prove to be more uniform. Considerable evidence suggests that the syndrome is mediated immunologically. The seven cases reported here were clinically similar, although the infectious etiologies were diverse. Leptospirosis antedated the neurologic syndrome in two cases, and a "viral" illness preceded the other five cases. The evolution of the syndrome was slowly progressive in each case, and six patients had prominent involvement of rhombencephalic structures. The progressive course was reversed rapidly with eventual full recovery in each instance after initiation of corticosteroid therapy. Our experience with these cases coupled with a review of the literature suggests that corticosteroid therapy should be considered in the subacute or chronic cases of parainfectious encephalomyelitis. 相似文献
126.
War is a complex social situation due to the interplay of multiple factors. Economical and political ones are of utmost importance, but human attitudes and motivations must be also taken into account. Being desirable to modify human transactions in such a way that they do not interfere with the basic right of everyone to a condition of physical and mental well-being, war must be abolished. The author contends that an understanding of behaviour through Psychology can be helpful in that aim. Aggression is considered the principal psychological cause of war. It is worth while to differentiate between aggression as an instrument for attaining a special end, and as pure hostility. Only in the first form, it is held here, does it play an important role in war. Psychogists must deal also with a wide range of states of mind that can be "served" by aggression: feelings of inferiority or insecurity, fear, greed, projections, compensations, rationalizations, etc. Scientific approach is not the only one Physiology brings to war prevention. It is equally important the wide dissemination of its conclusions among the general public. Information on the dynamics that prompt people to decide war would make it easier to control. This applies not only to political or military leaders, but also to civil populations. Concerning those two possible contributions of psychologists, scientific and educative, it is suggested the extensive use of psychodramatic techniques. Their richness lie in the lifelike experiences they convey to the participants, and particular aptitude to promote changes of attitudes. Investigation and information on the psychological processes related to war should be undertaken by international organizations of social scientists, acting simultaneously in several countries. Some of the initial steps they could further: 1) that prevention of war be a current subject matter in psychological courses; 2) that the World Health Organization take interest in this subject; 3) that psychologists participate in international political and economical bodies in order to clarify the psychological factors leading to war. 相似文献
127.
J Kachelhoffer C Mendel J Dauchel D Hohmatter JF Grenier 《Canadian Metallurgical Quarterly》1976,21(11):957-962
The effects of VIP on intestinal motility were studied on isolated canine jejunal loops ex vivo perfused at normothermia, under pulsatile flow with heparinized, oxygenated and nonrecirculated canine whole blood, by means of an intraluminal balloon. VIP was administered intraarterially either by 1 min injections or by long-time infusions. The results showed that for arterial concentrations of the polypeptide ranging between 25 pg/ml and 300-500 pg/ml a fast but short-lasting relaxant effect was observed. For higher concentrations VIP usually produced a biphasic response: The relaxant effect is followed by an increase of the basal muscular tone often accompanied, for concentrations higher than about 25 ng/ml, by a marked and transient increase in amplitude of the intestinal rhythmic contractions. During long-time infusions a biphasic response was also observed but both effects were of short duration. A cholingeric origin of the secondary contracting phase was expected but could not be demonstrated because, at blood concentrations at which atropine affected the biphasic response, not only was the contractile effect abolished but also the initial relaxing phase. It is suggested that the secondary contraction may be a "rebound excitation" of myogenic nature or a result of noncholingeric excitatory fiber stimulations. The short-lasting relaxant effect observed under the present experimental conditions, even during long-time infusion of the polypeptide, fails to argue for an important physiological role of VIP as an hormonal inhibitor of intestinal motility. The biphasic response, however, might have a physiological significance in so far as the aboral propulsion of the intestinal content requires a muscular inhibition which rapidly changes to contraction. 相似文献
128.
A randomized controlled trial of home care: clinical outcome for five surgical procedures 总被引:1,自引:0,他引:1
The clinical function of patients receiving home care after five surgical procedures was assessed. Hospital patients who normally would have received minimal nursing care at the end of their hospital stay were randomly assigned to an experimental home-care group or a control group who were discharged from hospital after the normal length of stay. Comprisons of "untoward events" (discomfort, infection, delayed healing, or complications) are reported for the two groups in five surgical categories (varicose vein stripping, herniorrhaphy, cholecystectomy, anal and rectal operations and abdominal hysterectomy) where the home-care program operated efficientyl. No apparent differences in the rates of untoward events were noted between hospital and home-care groups. It is concluded that home care should be considered for reasons other than clinical function, such as socio-economic functioning, the wishes of the patient, or more efficient use of hospital space. 相似文献
129.
Tobacco use is prevalent among youth with alcohol and other drug problems, yet this issue has received limited research and clinical attention. This study reports on a controlled evaluation of a cigarette smoking intervention with 54 adolescents in treatment for substance abuse, ages 13-18 (22% female). Participants were assessed at 4 time points. A greater proportion of participants in the treatment condition (n = 26) reported cessation attempts and point abstinence than did control participants (n = 28) at all time points. However, significant differences were found only for point abstinence at a 3-month follow-up. These findings provide initial support for the efficacy of a smoking cessation intervention delivered in the context of adolescent substance abuse treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
130.
Muller Jeff M.; Brunelli Susan A; Moore Holly; Myers Michael M.; Shair Harry N. 《Canadian Metallurgical Quarterly》2005,119(5):1384
Although dopamine is necessary for mammalian adult pair-bond formation and maternal behavior, its function in infant social behavior and attachment has been less thoroughly explored. The vocalization rate of an isolated rat pup is influenced by recent social contact. Interactions with the dam potentiate vocalization rate. Interactions with littermates or adult males do not. Systemic administration of the D2-family agonist quinpirole specifically blocked maternal potentiation at doses that did not alter vocalization rate in an isolation prior to dam contact. This result was not explained by quinpirole's effects on body temperature or locomotion. The results are consistent with a role for dopamine in infant social behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献