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101.
Hypoxic and low-temperature effects on the thermal regulation and the content of catecholamines (epinephrine--E and norepinephrine--NE) in mice have been compared. Continuous and repeated hypoxia brought about a significant drop of the rodent body temperature and heat content. Found was a significant elevation of catecholamines in the pituitary and adrenal tissues, and blood plasma with E prevalence after the continuous exposure. Repeated stimulus resulted in a more pronounced effect. Exception was the adrenal tissue where enhanced E and NE secretion into blood was noted. The uninterrupted and repeated cold conditions were also responsible for heat release. Continuous exposure to low temperature increased NE and decreased insignificantly E in blood and adrenal. Multiple stimulation increased sharply catecholamines concentration in blood plasma with the dominance of epinephrine in the pituitary gland, and norepinephrine in the adrenal.  相似文献   
102.
103.
Mating speed of flies which have been aged either in the light, in the dark or in a light-and-dark cycle was measured using two strains, Rochester (R) and Salvador (S), of Drosophila mercatorum. A significant difference in mating tendency depending on the condition of pretreatment was found between R and S strains, while both strains showed a similar pattern of the diurnal rhythm in the light-and-dark cycle. Compared under the same conditions, S flies usually showed a higher mating speed than R flies. Mating speed seems to be affected by at least two different genetic systems. One of them is the genetic system determining absolute speed of mating. Another is the genetic system determining sensitivity to the environmental conditions. There may be considerable differentiation in both systems between R and S strains.  相似文献   
104.
The present study was undertaken to determine the conditions under which acute periods of hemorrhagic shock induce bacterial translocation. Rats (at least six per group) were anesthetized intraperitoneally with the barbiturate, pentobarbital (50 or 65 mg/kg), or the inhalation anesthetic methoxyflurane. Following anesthesia, the femoral artery was catheterized, from which blood was withdrawn to maintain a mean arterial blood pressure of 30 mmHg for 30, 60, or 90 min, followed by reinfusion of shed blood. Instrumented, but nonshocked animals served as controls. Rats were sacrificed at 0, 2, or 24 hr postshock, and quantitative bacterial cultures of the mesenteric lymph node complex (MLN), liver, and spleen were made. Within groups, the effects of heparinization were also determined. In pentobarbital-treated animals, regardless of the extent of heparinization, consistent translocation to both MLN and distant organs occurred when shock was prolonged for 90 min, and assessment of translocation was made 24 hr after reinfusion of shed blood. Furthermore, a mortality rate of approximately 30% was found in rats subjected to this protocol. The magnitude of translocation was less consistent, and did not differ from that in sham shock controls, under other conditions of shock and evaluation. In rats anesthetized with methoxyflurane, no mortality occurred, and no statistical significance between the incidence or degree of translocation in shocked animals vs. sham shock controls could be demonstrated, regardless of the shock protocol. In additional studies, effects of these anesthetics on intestinal morphology and superior mesenteric arterial (SMA) flow in the context of hemorrhagic shock were assessed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
105.
Little is known about the effects of a parent's brain injury and subsequent disabilities on the children in the family. This study examines 24 families in which one parent is brain injured. In each family the children were born before the parent's injury and still lived at home at the time of interview. Reports of the uninjured parent indicate that most of the children experienced some degree of negative behavioural change after the parent's injury. In 10 of the families, significant and problematic changes occurred. Types of problems included poor relationship with the injured parent, acting-out behaviour and emotional problems. Correlates of poor outcomes for the children were: (1) injured parent's gender, (2) compromised parenting performance of the injured parent, (3) compromised parenting performance of the uninjured parent and (4) depression in the uninjured parent. This study points to the importance of recognizing traumatic brain injury as a major family stressor.  相似文献   
106.
Examination of 400 patients with occupational bronchial asthma helped to identify various clinical and pathogenetic variants of the disease in accordance with independent and combined occupational allergens and irritants. The authors evaluated diagnostic value of endonasal tests with occupational allergen, rhinocytologic tests and some specific allergologic blood tests in vitro.  相似文献   
107.
Recently, mu-, delta- and kappa-opioid receptors have been cloned and relatively well-characterized. In addition to three major opioid receptor types, more extensive studies have suggested the possible existence of other opioid receptor types that can be classified as non-mu, non-delta and non-kappa. Based upon anatomical and binding studies in the brain, the sensitive site for an endogenous opioid peptide, beta-endorphin, has been postulated to account for the unique characteristics of the opioid receptor defined as a putative epsilon-opioid receptor. Many epsilon-opioid receptors are functionally coupled to G-proteins. The functional epsilon-opioid receptors in the brain are stimulated by bremazocine and etorphine as well as beta-endorphin, but not by selective mu-, delta- or kappa-opioid receptor agonists. Epsilon-opioid receptor agonists injected into the brain produce profound antinociception. The brain sites most sensitive to epsilon-agonist-induced antinociception are located in the caudal medial medulla such as the nucleus raphe obscures, nucleus raphe pallidus and the adjacent midline reticular formation. The stimulation of epsilon-opioid receptors in the brain facilitates the descending enkephalinergic pathway, which probably originates from the brainstem terminating at the spinal cord. The endogenous opioid Met-enkephalin, released in the spinal cord by activation of supraspinal epsilon-opioid receptors, stimulates spinal delta2-opioid receptors for the production of antinociception. It is noteworthy that the epsilon-opioid receptor-mediated pain control system is different from that of other opioid systems. Although there appears to be no epsilon-selective ligand currently available, these findings provide strong evidence for the existence of the putative epsilon-opioid receptor and its unique function in the brain.  相似文献   
108.
The medial nucleus of the amygdala (Me), bed nucleus of the stria terminalis (BNST), and medial preoptic area (MPOA) regulate copulation in the male hamster. The present study identified neuropeptide Y-immunoreactive (NPY-IR) neurons in the BNST and Me with the greatest concentration in the posteromedial and posteriordorsal subdivisions of these nuclei, respectively. NPY-IR filters are found in all three nuclei with dense plexi of NPY-IR varicosities in the most medial subdivisions. Substance P neurons are also densely concentrated in the posterior BNST and Me; however, no neurons contained both peptides. Thus, NPY and substance P neurons comprise two distinct populations within the BNST and Me of the hamster.  相似文献   
109.
110.
The case of a 40-year-old male patient with obstructive sleep apnea syndrome (OSAS) is reported, with emphasis on treatment with a dental appliance. This therapeutic approach, which has been focused on recent research, has as its objective, the posturing of the mandibule and, consequently, the tongue more anteriorly, thus in turn leading to an increase in the posterior oropharyngeal airway space (PAS). Cephalometry contributed determining in this case whereby enlargement limits were observed in the PAS with mandibular displacement. Clinical and polysomnographic controls showed subjective reduction of the excessive daytime sleepiness and objective decrease in apneas intensity to normal limits. Eight months follow-up evidenced the steady improvement.  相似文献   
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