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61.
62.
E A Reece H N Winn J P Hayslett J Coulehan M Wan J C Hobbins 《American journal of perinatology》1990,7(2):193-197
The effect of gestation on the rate of decline in renal function was studied in 11 pregnancies complicated by diabetic nephropathy. For each pregnancy, serum creatinine levels were available within 4 years before pregnancy, during pregnancy, and within 4 years after delivery. Although all of these patients were hypertensive and had increased proteinuria during pregnancy, the mean serum creatinine just prior to conception (1.3 +/- 0.5 mg/dl) and the last follow-up value (1.2 +/- 0.3 mg/dl) were not significantly different. When the inverse of serum creatinine (1/Scr) was used to estimate creatinine clearance, the renal function was either improved or remained stable in the majority of the pregnancies (7 of 11). The observed decline in renal function through the end of follow-up appeared to be consistent with the expected natural course of diabetic nephropathy in the absence of pregnancy. Furthermore, the slope for inverse serum creatinine before and after pregnancy was not significantly different. In conclusion, pregnancy in patients with mild to moderate diabetic nephropathy does not seem to accelerate the rate of decline in renal function. 相似文献
63.
MP Richardson TJ Williamson SW Lenton MJ Tarlow PT Rudd 《Archives of disease in childhood》1995,72(4):294-297
Transient evoked otoacoustic emissions (TEOAEs) are low amplitude sound waves produced by the healthy cochlea. They can be recorded with a microphone in the external ear. TEOAEs are abolished by hearing losses of 30 dB or more. The feasibility of using TEOAEs as a screening test for hearing loss in children was studied. TEOAE recordings were attempted in 56 children attending an audiology clinic. Recordings were possible from both ears in 52 children; of these 104 ears, 32 had hearing deficits of 30 dB or more. Hearing status was compared with the results of six TEOAE screening criteria. All criteria had a sensitivity of 1.00. Four standard TEOAE criteria yielded specificities of 0.46-0.58. Two new criteria derived from analysis of limited frequencies from the TEOAE waveform gave specificities of 0.76 and 0.82. It can be concluded that, when appropriate pass/fail criteria are employed, TEOAEs are a feasible screening test in children. 相似文献
64.
Open-loop accommodation in emmetropia and myopia 总被引:1,自引:0,他引:1
PURPOSE: To investigate the influence of method of measurement and refractive error on the open-loop accommodation response. METHODS: Open-loop accommodation was measured in darkness (dark accommodation, DA) and using a pinhole pupil (pinhole accommodation, PA) in emmetropic subjects (EMMs, n = 63), subjects with late-onset myopia (LOMs, n = 50) and subjects with early onset myopia (EOMs, n = 51). Further a control experiment examined the differences between DA and bright-field accommodation (BA) conditions in a subset of subjects. All measurements of open-loop accommodation were carried out monocularly using a Canon R1 infra-red optometer in static recording mode. All myopic subjects were fully corrected using soft contact lenses. RESULTS: A significant variation (p < 0.001) in open-loop accommodation was found between DA and PA, but no variation in open-loop level was observed between the three refractive groups. There was no interaction between these two factors. No significant difference was found between the BA level and DA level in any of the refractive groups. CONCLUSIONS: Open-loop accommodation response positions vary according to the experimental conditions employed during measurement. No refractive group differences in the open-loop response were apparent. 相似文献
65.
H N Winn J F Setaro M Mazor E A Reece H R Black J C Hobbins 《American journal of obstetrics and gynecology》1988,159(5):1135-1136
Maternal cardiovascular complications have been attributed to the dramatic hemodynamic changes associated with labor and delivery in patients with Takayasu's arteritis. The role of central hemodynamic monitoring in the management of a pregnant patient with severe Takayasu's arteritis is discussed. 相似文献
66.
G. O. Atkinson Jr. J. B. Wyly B. B. Gay Jr. T. I. Ball K. J. Winn 《Pediatric radiology》1988,18(1):28-31
Idiopathic fibrosing pancreatitis is a chronic process of unknown etiology characterized by extensive infiltration of the
pancreatic parenchyma by fibrous tissue [1, 2]. This disease process is uncommon in the pediatric patient and is consequently
rarely considered in the differential diagnosis of abdominal pain and jaundice in the child. The sonographic demonstration
of a dilated biliary tree and common bile duct compressed by an enlarged pancreas may be the first suggestion of this entity.
Two patients with idiopathic fibrosing pancreatitis and obstructive jaundice are reported with a review of the clinical, radiographic,
and pathologic findings. 相似文献
67.
OBJECTIVE AND IMPORTANCE: We describe a unique case of multiple bilateral cervical root injuries without ligamentous or bony injury secondary to a sandblast accident. CLINICAL PRESENTATION: A 19-year-old man sustained a sandblast injury to his face, neck, chest, and upper extremities, with immediate loss of motor and sensory function occurring in both of his upper extremities. Cervical spine x-rays, computed tomography, and magnetic resonance imaging demonstrated no fracture, soft tissue abnormality, or malalignment. The restriction of deficits to the patient's upper extremities suggested a central cervical spinal cord injury, bilateral brachial injuries, or a conversion disorder. INTERVENTION: Cervical computed tomographic myelography revealed multiple bilateral nerve root injuries. CONCLUSION: This case report is unique in the literature in that it describes a patient with multiple cervical nerve root injuries secondary to sandblast injury without ligamentous or bony injury. Although magnetic resonance imaging remains the diagnostic modality of choice in patients with acute spinal cord injury, it is deficient in demonstrating cervical root injury in the acute setting. In this setting, computed tomographic myelography is superior. 相似文献
68.
OBJECTIVE: To determine the vaginal-rectal colonization rate with group A streptococci in late pregnancy. METHODS: All patients delivering at a northern New England hospital over a 38 month period had 35-37 week vaginal-rectal swabs cultured for group A and group B streptococci, using selective media and slide agglutination. RESULTS: Six thousand nine hundred forty-four screening cultures were obtained. Among these 1,393 were positive for group B streptococci and 2 for group A streptococci, yielding colonization rates of 20.1% and 0.03%, respectively. CONCLUSIONS: Vaginal-rectal colonization with group A streptococci is rare, arguing against the need for establishing group A streptococcal screening programs in pregnancy. An approach for managing this uncommon finding is presented. 相似文献
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