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Background: The long‐term success rates achieved in dental implantology suggest that flexibility might well exist within the various implant systems to a degree that an altered protocol (ie, one‐stage surgery and immediate or early loading) can be performed under controlled conditions. However, before variations of the protocol can be considered for general use, they must be subjected to critical analysis, particularly with respect to the predictability of osseointegration, alteration of soft tissue barrier, and relative change in bone height around the implants. Purpose: The aim of this prospective multicenter study was to evaluate implant survival and periimplant conditions around endosseous implants placed in a one‐stage surgical procedure and early loading. Materials and Methods: A total of 170 implants were placed in 40 patients with mandibular edentulism and were functionally loaded within 6 weeks with overdentures (n = 30) or fixed prostheses (n = 10). All patients and prosthetic constructions were evaluated according to a standardized protocol during 3 years of follow‐up. Cumulative implant survival rates were calculated, and implant loss in relation to implant size and bone quality and quantity were evaluated. Furthermore, the protocol included assessment of clinical (plaque and bleeding scores, prosthesis stability) and radiographic parameters. Results: Over a period of 3 years, the implant survival rate was 93% for both implants and prostheses (fixed or removable). No implants were lost after the first year of loading. The periimplant tissues were in a healthy condition. Mean marginal bone resorption from the time of loading to the 3‐year follow‐up was 0.41 mm (SD 0.52). Conclusions: From this study it may be concluded that early loading results in good implant survival and proper periimplant health in edentulous mandibles.  相似文献   
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Exocrine pancreatic insufficiency (EPI) is a well-studied syndrome in domestic animals. EPI occurs when severe progressive loss of tubulo-acinar tissue from atrophy or inflammatory destruction results in insufficient secretion of digestive enzymes and clinical signs of malabsorption. However, the literature on EPI in birds is limited. The syndrome has been previously described in several cases where the diagnosis was based on clinical signs due to malabsorption-like light-coloured voluminous faeces, voracious appetite, coprophagia and weight loss, and on the response to treatment with pancreatic enzyme formulas. To enable a more scientific approach to the diagnosis of pancreatic functional disorders in pigeons, reference values of plasma amylase (382 to 556 IU/l), lipase (0 to 5 IU/l), and faecal activities of amylase (13 to 16 IU/l) and trypsin (11 to 14 IU/l) were determined in 24 adult pigeons. A case of EPI in a racing pigeon (Columba livia domestica) is reported, based on the clinical signs and the measurement of faecal amylase and trypsin activity.  相似文献   
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OBJECTIVE: To examine the dose effect of maternal milk on neonatal morbidity of very low-birth-weight (<1.5 kg) infants. DESIGN: Prospective observational study. SETTING: An urban tertiary care neonatal intensive care unit and follow-up clinic. POPULATION: One hundred nineteen singleton very low-birth-weight infants admitted from January 1, 1997, to February 14, 1999 (mean birth weight, 1056 g; mean gestational age, 28 weeks; 57% male; and 43% white). METHODS: A comparison of the effect on neonatal outcomes of daily graded doses (1-24, 25-49, and > or = 50 mL/kg of body weight) of maternal milk through week 4 of life vs a reference group receiving no maternal milk. MAIN OUTCOME MEASURES: Neonatal outcomes examined included rates of sepsis after age 5 days, retinopathy of prematurity, chronic lung disease, necrotizing enterocolitis, jaundice, duration of ventilator dependence, and length of hospital stay. RESULTS: Seventy-nine infants (66%) received maternal milk, of whom 32 received at least 50 mL/kg per day through week 4 of life. Poisson regression analysis adjusting for birth weight, sex, and ethnicity revealed that the mean number of episodes of sepsis for infants receiving at least 50 mL/kg per day was lower by a factor of 0.27 (95% confidence interval, 0.08-0.95) compared with infants receiving no maternal milk. There was no effect of maternal milk on other neonatal outcomes. CONCLUSIONS: A daily threshold amount of at least 50 mL/kg of maternal milk through week 4 of life is needed to decrease the rate of sepsis in very low-birth-weight infants, but maternal milk does not affect other neonatal morbidities.  相似文献   
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Using dissociated rat dorsal root ganglion (DRG) neurons, we have explored the ability of nerve growth factor (NGF) to acutely (within minutes) sensitize responses of nociceptors to capsaicin or noxious heat during postnatal development. While robust sensitization of noxious heat or capsaicin responses by NGF is observed in adult DRG neurons, responses to such stimuli in trkA-positive neurons from early postnatal animals are not sensitized by NGF. Neurons acquire sensitivity to the hyperalgesic effects of NGF between postnatal days 4 and 10 (P4-P10). In contrast to NGF, bradykinin sensitizes responses to noxious heat in both adult and neonatal DRG neurons. These observations suggest a developmental switch in signal transduction cascades linking trkA receptors to hyperalgesia during postnatal development and differences in the signaling pathways mediating bradykinin- and NGF-induced sensitization.  相似文献   
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The authors examined the relationship of preinjury interpersonal resources and stressors to parental adaptation following pediatric traumatic brain injury (TBI) and orthopedic injury. Parents of children with severe TBI (n = 53), moderate TBI (n = 56), and orthopedic injuries (n = 80) were assessed soon after injury, 6 and 12 months after the initial evaluation, and at an extended follow-up with a mean of 4 years postinjury. General linear model analyses provide support for both main and moderating effects of stressors and resources on parental adjustment. Support from friends and spouse was associated with less psychological distress, whereas family and spouse stressors were associated with greater distress. The results also reveal a marked decline in injury-related stress over follow-up for families in the severe TBI group who reported a combination of high stressors and high resources. The decline suggests that interpersonal resources attenuated long-term family burden because of severe TBI. The findings are discussed in terms of their implications for intervention following TBI.  相似文献   
90.
Hematophagous Diptera landing on a horse were removed by vacuum, and their numbers were related to a paired carbon dioxide-baited suction trap at three locations in southern California where West Nile virus activity was high during the preceding year. Insects collected from the horse included mosquitoes (nine species), biting midges (Culicoides sonorensis Wirth & Jones), and black flies (Simulium bivittatum Malloch). Mosquitoes were predominantly collected from the head, crest, withers, neck, chest, and shoulders of the horse, whereas biting midges and black flies were predominantly collected from the ventral midline of the horse. Culex erythrothorax Dyar was by far the most abundant mosquito species collected overall. Frequency of engorgement for mosquitoes captured from the horse ranged by species from zero to 58.3%, with Culex pipiens quinquefasciatus Say having the lowest value (16.7% or one of six mosquitoes) of species that fed on the horse. The number of insects captured at the horse and paired CO2-baited suction trap was not different for Anopheles franciscanus McCracken, Culex tarsalis Coquillett, and S. bivittatum. Cx. p. quinquefasciatus was captured in greater numbers in the CO2-baited suction trap, whereas Anopheles hermsi Barr & Guptavanji, Cx. erythrothorax, Culiseta inornata (Williston), and Culiseta particeps (Adams) were captured in greater numbers from the horse. The horse biting rate was very low for Cx. p. quinquefasciatus, intermediate for Cx. tarsalis, and very high for Cx. erythrothorax. Both Cx. tarsalis and Cx. erythrothorax should be considered likely epizootic vectors of West Nile virus to horses in rural southern California.  相似文献   
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