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231.
Patrick W. Slater D. Bradley Welling Joseph H. Goodman Michael E. Miner 《The Laryngoscope》1998,108(9):1408-1412
Objective: The purpose of the study was to demonstrate the utility of the middle fossa transpetrosal approach with anterior petrosectomy for difficult-to-access petroclival and pontine lesions. Study Design: Retrospective case review in academic tertiary referral center. Methods: Patients for inclusion had pontine and prepontine lesions of the petroclival region. Middle fossa transpetrosal approach with anterior petrosectomy with excision or biopsy of the lesion was performed. The main outcome measure was postoperative neurologic status including motor and cranial nerve function. Results: No patient experienced neuromuscular compromise or cranial nerve deficits as a direct result of the surgical procedure. Complications consisted of a subdural temporal lobe hemorrhage and one case of cerebrospinal fluid rhinorrhea. Conclusions: The middle fossa transpetrosal approach with anterior petrosectomy was utilized for five patients with petroclival or pontine tumors. In this small series, it served well to spare cranial nerves and allowed avoidance of serious vascular injury. To our knowledge, this is the first reported use of this procedure for pontine venous angiomas. 相似文献
232.
Oberyszyn TM; Conti CJ; Ross MS; Oberyszyn AS; Tober KL; Rackoff AI; Robertson FM 《Carcinogenesis》1998,19(3):445-455
The beta2 integrin (CD 18/CD 11 a, b, c) family of proteins mediate
adherence of leukocytes to vascular endothelium and the associated ligand,
intercellular adhesion molecule-1 (ICAM-1; CD 54), interacts with beta2
integrin proteins to allow transendothelial migration of leukocytes into
sites of inflammation. The present study examines the function of these
proteins in a murine model of acute cutaneous inflammation induced
following topical application of 12-O- tetradecanoylphorbol-13-acetate
(TPA) to the dorsal epidermis of SENCAR mice and in a model of skin
multistage carcinogenesis. At 24 h following topical application of TPA to
the dorsal epidermis of mice, dermal leukocytes expressed higher levels of
beta2 integrin protein compared with the lower levels of beta2 integrin
protein expression by peripheral blood leukocytes. ICAM-1 protein was
localized to epidermal keratinocytes and vascular endothelium in
TPA-treated skin and to proliferating papilloma cells. Intravenous (i.v.)
injection of either 50 microg anti-beta2 integrin antibody alone or in
combination with anti-ICAM-1 antibody significantly inhibited both
TPA-stimulated neutrophil infiltration into the dermis (P < 0.001) and
myeloperoxidase (MPO) activity (P < 0.03 anti-beta2 integrin antibody; P
< 0.01 anti- beta2 integrin + ICAM-1 adhesion molecule antibodies), but
had no effect on TPA-induced epidermal hyperplasia. In addition, injection
of either anti-ICAM-1 adhesion molecule antibody alone (P < 0.004) or in
combination with anti-beta2 integrin antibody (P < 0.001) significantly
inhibited TPA-induced production of 7,8-dihydroxy-2'-deoxyguanosine (8-
OHdG) immunoreactive proteins by epidermal keratinocytes. Beta2
integrin/ICAM-1 adhesion molecules work in concert to regulate migration,
retention and functional activation of leukocytes within the dermis during
TPA-induced skin inflammation and within stromal tissue of papillomas that
form during multi-stage carcinogenesis. Agents that inhibit these
receptor/ligand interactions may be useful in defining the roles of
specific cell populations in cutaneous inflammation and multistage
carcinogenesis and may also have potential as anti-promoting and
anti-progression agents.
相似文献
233.
234.
Bolontrade MF; Stern MC; Binder RL; Zenklusen JC; Gimenez-Conti IB; Conti CJ 《Carcinogenesis》1998,19(12):2107-2113
In this study we have analyzed the vascular response induced in the two-
stage carcinogenesis model in SENCAR mice. The role of angiogenesis has not
been explored in this model, which is the paradigm of multistage
carcinogenesis and a model for neoplastic lesions derived from exophytic
premalignant lesions (e.g. colon carcinoma, bladder papilloma). We
investigated if angiogenesis is involved in the formation of papillomas and
in the progression from papilloma to carcinoma. To this end we analyzed the
vasculature of normal and hyperplastic skin, focal epidermal hyperplasias
that are precursors of papillomas, papillomas at different stages and
squamous cell carcinomas. We also analyzed the vascularization of
papillomas induced in two strains of mice that differ in their
susceptibility to malignant progression. We show here that angiogenesis is
turned on in the earliest stages of papilloma formation. In late stages,
regardless of state of progression, the predominant response is an increase
in the size of blood vessels. Thus, in the SENCAR mouse model,
representative of exophytic tumors, the angiogenesis switch is a very early
event, probably mechanistically related to the development of the primarily
exophytic lesions. Therefore, the density of blood vessels cannot be used
as a predictor of malignant progression in this model.
相似文献
235.
236.
OBJECTIVE: To test a quality improvement approach called COPE (Client-Oriented, Provider-Efficient services), for use in strengthening health systems and supporting Integrated Management of Child Health (IMCI) efforts. DESIGN: Pre- and post-intervention observations of client/provider interactions, facility audits, staff and client surveys, and focus groups to evaluate differences between eight COPE intervention and eight matched non-intervention facilities after a 15-month intervention in 2001. SETTING: Primary care clinics in Guinea and Kenya. STUDY PARTICIPANTS: Health care providers and child caregivers. INTERVENTIONS: Over 15 months, the intervention supported four COPE exercises at each intervention site, supported supervisor training in quality management, and organized minimal training in topics selected by site staff as areas where training was needed. MAIN OUTCOME MEASURES: Differences in staff's and child caregiver's knowledge, attitudes, and practices; differences in the quality of services provided. RESULTS: On almost every quality indicator (over 65 indicators), whether reported by staff, observed by evaluators, or reported by clients, the intervention sites performed statistically significantly better than control sites. INTERVENTION: sites were cleaner and more pleasant, with more respect and information for clients, and more privacy. Staff had better personal communication skills, better diagnostic skills, and prescribing practices and gave better home care instructions to carers. Clients in intervention sites were more informed and more satisfied, and their children had better immunization coverage than those in control sites. CONCLUSION: COPE is a simple process, yet our study confirms that it can have a very dramatic effect on the quality of services. This study demonstrated how all areas of quality can be addressed by empowering health care providers to take action by using COPE. We suggest that COPE can complement Integrated Management of Childhood Illness (IMCI) training and can help to achieve better health for children. 相似文献
237.
PURPOSE: To identify children with isoametropic amblyopia due to moderate to high hyperopia and evaluate associated findings and visual acuity outcome. METHODS: Charts from two university's pediatric ophthalmology clinics were reviewed retrospectively. Healthy children with > or = +4.5 D spherical equivalent who did not have anisometropia > or = 1.5 D were selected for data collection. The charts of qualifying children with bilateral amblyopia (visual acuity of 20/40 or less) were further analyzed. RESULTS: Identified were 418 children with the above set of criteria for hyperopia; 36 of these children had isoametropic amblyopia (bilateral amblyopia). This gives an estimated prevalence of isoametropic amblyopia of 8.6% in children with at least 4.5 D of hyperopia in one or both eyes. The children with isoametropic amblyopia presented at a later age (5 years, 1 month) than the overall group of hyperopes (3 years, 5 months). Strabismus was less prevalent in this group (64%) than in the entire population of children with high hyperopia (81%). These children's amblyopia responded well to treatment with glasses, and patching in 13 (36%) cases. Surgical intervention for residual strabismus was necessary in very few cases (2 of 36, 5.5%). CONCLUSION: Children with hyperopia > or = 4.5 D have an increased risk of amblyopia and strabismus that further threatens their future visual function. Isoametropic amblyopia is a real risk in these children. Based on these results, hyperopic correction should be prescribed for children with > or = 4.5 D of hyperopia even if no strabismus or fixation preference is detected, to reduce this risk. Screening programs should also be in place to identify these children at an early age. 相似文献
238.
Robert Sean Miller Robert A Jahrsdoerfer George T Hashisaki Bradley W Kesser 《Otology & neurotology》2006,27(2):189-192
OBJECTIVE: Salivary fistula is an uncommon and unreported yet meaningful complication associated with the repair of congenital aural atresia. The capsule of the parotid gland may be violated during two steps of the operation: the initial dissection around the glenoid fossa or while aligning the auricle with the bony canal at the end of the procedure. We present the first described series of patients with salivary fistula after repair of congenital aural atresia. STUDY DESIGN: Retrospective case review from 1985 to 2004. SETTING: Tertiary referral center. PATIENTS: We included all patients who were diagnosed with a salivary fistula after congenital aural atresia repair. MAIN OUTCOME MEASURE: The diagnosis of a salivary fistula or salivary tissue in the external auditory canal after atresia repair was based on one of the following criteria: 1) identification of a fistula tract or salivary tissue in the external auditory canal, 2) otorrhea positive for amylase, or 3) intermittent otorrhea associated with eating. RESULTS: Of 1,500 patients operated on for aural atresia, we identified 6 with salivary fistula after atresia repair. Salivary fistulas were diagnosed from 15 days to 10 years postoperatively, and the duration ranged from 6 months to 14 years. Treatment included observation, medical management, and surgical intervention. CONCLUSION: Salivary fistulas in the external auditory canal may present with granulation tissue, persistent crusting, or persistent otorrhea; it is therefore necessary to consider salivary fistula when managing these findings in postoperative congenital aural atresia patients. Salivary fistula secondary to repair of congenital aural atresia may be managed conservatively or surgically. 相似文献
239.
240.
Alexandre T Rotta Mário Eduardo G Viana Budi Wiryawan Guilherme A Sargentelli Mark S Dowhy Walter A Zin Bradley P Fuhrman 《Pediatric critical care medicine》2006,7(6):562-570
OBJECTIVE: To evaluate the independent and combined effects of high-frequency oscillatory ventilation (HFOV) and partial liquid ventilation (PLV) on gas exchange, pulmonary histopathology, inflammation, and oxidative tissue damage in an animal model of acute lung injury. DESIGN: Prospective, randomized animal study. SETTING: Research laboratory of a health sciences university. SUBJECTS: Fifty New Zealand White rabbits. INTERVENTIONS: Juvenile rabbits injured by lipopolysaccharide infusion and saline lung lavage were assigned to conventional ventilation (CMV), PLV, HFOV, or high-frequency partial liquid ventilation (HF-PLV) with a full or half dose (HF-PLV1/2) of perfluorochemical (PFC). Uninjured ventilated animals served as controls. Arterial blood gases were obtained every 30 mins during the 4-hr study. Histopathologic evaluation was performed using a lung injury scoring system. Oxidative lung injury was assessed by measuring malondialdehyde and 4-hydroxynonenal in lung homogenates. MEASUREMENTS AND MAIN RESULTS: HFOV, PLV, or a combination of both methods (HF-PLV) resulted in significantly improved oxygenation, more favorable lung histopathology, reduced neutrophil infiltration, and attenuated oxidative damage compared with CMV. HF-PLV with a full PFC dose did not provide any additional benefit compared with HFOV alone. HF-PLV1/2 was associated with decreased pulmonary leukostasis compared with HF-PLV. CONCLUSIONS: The combination of HFOV and PLV (HF-PLV) does not provide any additional benefit compared with HFOV or PLV alone in a combined model of lung injury when lung recruitment and volume optimization can be achieved. The use of a lower PFC dose (HF-PLV1/2) is associated with decreased pulmonary leukostasis compared with HF-PLV and deserves further study. 相似文献