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91.
Luciana Butini Oliveira Wagner Marcenes Thiago Machado Ardenghi Aubrey Sheiham Marcelo Bönecker 《Dental traumatology》2007,23(2):76-81
Abstract – The main objective of this study was to assess the epidemiology of traumatic dental injuries (TDI) to the primary teeth of preschool children and second, to investigate whether TDI were related to anterior open bite and, third, whether TDI are related to socio-economic circumstances in an urban Brazilian population. A clinical examination was performed during the National Day of Children's Vaccination. TDI were classified according to the modified classification proposed by Ellis. In addition to those criteria the presence of tooth discoloration was recorded. An interview was carried out with mothers or guardians. The data collected included mother's level of education and living conditions. The prevalence of TDI was 9.4%. The maxillary central incisors were the most affected teeth. Most children with a TDI experienced traumatic injuries to one tooth (6.3%), while 2.8% had two and 0.4% had three traumatized teeth. The most common crown fracture was in enamel only (68.8%), followed by crown fracture of enamel and dentin (13.8%). Missing teeth following trauma occurred in 10.9% of those with TDI. The prevalence of tooth discoloration was 5.1%. Children with anterior open bite had twice the level the level of TDI compared to those with normal occlusions ( P = 0.001). Socio-economic factors were not statistically significantly associated with the occurrence of TDI. The prevalence of dental injuries in Brazilian preschool children was low. Children with anterior open bite experienced more dental injuries. Neither of the indicators of socio-economic status was related to the prevalence of TDI. 相似文献
92.
Female Djungarian hamsters (Phodopus sungorus) have proportionately more adipose tissue in superficial depots than males of similar age and body composition. In both sexes, the proportion in superficial depots increases with increasing fatness. This species may be useful as a model for human obesity because it becomes as obese as modern humans without genetic, surgical or dietary manipulation and the sex differences in adipose tissue distribution resemble those of humans. 相似文献
93.
94.
D J Ballard D S Strogatz E H Wagner D S Siscovick S A James D G Kleinbaum C A Williams L M Cutchin M A Ibrahim 《American journal of preventive medicine》1986,2(5):278-284
As part of the Edgecombe County High Blood Pressure Control Program, a medical record review was conducted within a multispecialty private group practice in the county. The purposes of the review were to assess the relationship between the process of medical care and blood pressure control and to explore the variation in level and impact of medical care by race and sex. At the end of a three-year period, 41 percent of 628 hypertensive patients from the practice had uncontrolled diastolic blood pressure (DBP), as defined by Hypertension Detection and Follow-up Program criteria. The percentage of uncontrolled hypertensives ranged from 53 percent for black men to 34 percent for white women. Hypertensive patients whose physicians were more aggressive in their use of antihypertensive drug therapy were more likely to be controlled. The effect of the level of physician drug aggressiveness tended to be more pronounced for blacks than for whites. Differences by race in exposure to and efficacy of aggressive drug treatment may influence racial variation in blood pressure control. 相似文献
95.
96.
Phrenic and cervical sympathetic nerve responses to hypercapnia were examined before and after anesthesia in twelve midcollicularly decerebrated, vagotomized, glomectomized, paralyzed and ventilated cats. We measured responses of integrated phrenic and cervical sympathetic nerve activities to increases in end-tidal PCO2 (PETCO2) from apneic threshold to approximately 30 torr above threshold. All cats were studied first in the unanesthetized state. Six cats were then restudied after a quarter of a usual dose of chloralose/urethane (10 mg/kg and 62.5 mg/kg, respectively) and then after half the usual dose of chloralose/urethane (20 mg/kg and 125 mg/kg). The other six animals were restudied after quarter of a standard dose of pentobarbital (9 mg/kg), after half the standard dose (18 mg/kg) and then after the full (35 mg/kg) dose. Both anesthetic agents led to significant increases in apneic thresholds for both phrenic and sympathetic nerve activities. These agents also caused dose-dependent decreases in peak, tonic and respiratory-related sympathetic nerve activities. Peak (tidal) phrenic nerve activities, in comparison, were much less affected by the anesthetic agents. CO2 response curves showed that both of these anesthetic agents depressed, at any given level of PETCO2, respiratory-related sympathetic nerve responses more than the responses found in the phrenic nerve. We conclude that the relations between peak, tonic (i.e. between phasic bursts) and respiratory-related sympathetic nerve activities and phrenic nerve activity can be altered by anesthesia. 相似文献
97.
98.
99.
Caroline Richmond 《Canadian Medical Association journal》1991,144(4):411-412
100.
D. Caroline Blanchard Jon K. Shepherd R. J. Rodgers Robert J. Blanchard 《Psychopharmacology》1992,106(4):531-539
The Proxemics/Activity test and the Eat/Drink test, two components of the Anxiety/Defense Test Battery, were developed to measure defensive reactions to situations associated with a natural predator (cat). In the present studies the behavioral effects of 8-OH-DPAT treatment (0.01–1.0 mg/kg, SC) were entirely consistent with anxiety/fear reduction. These effects included an increase in time spent near the cat compartment, and a complimentary decrease in time spent farthest from this compartment, together with an increase in transits and locomote behavior. 8-OH-DPAT (1.0 mg/kg) also increased eat frequencies and durations (highly preferred food) both during and following cat presentation, without influencing drinking. This finding is discussed with reference to previous findings with 8-OH-DPAT in studies assessing both food intake and anxiolysis. Interestingly, 8-OH-DPAT was more potent in a majority of its effects in female subjects, a finding consistent with recent neurochemical data. These findings provide important behavioral evidence for a sexual differentiation in 5-HT function, and support the case for greater emphasis on female subjects in animal models of anxiety.Supported by NIH MH42803 and RCMI Grants RR03061 and RR01825 相似文献