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71.
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We describe a 39-year-old man in whom progressive pulsatile proptosis developed 2 days after he suffered a head injury. Computed tomography revealed an isolated blow-in fracture of the orbital roof with herniation of the left frontal lobe into the orbit. Neurosurgical intervention to repair the orbital defect led to full recovery.  相似文献   
73.
Idiopathic perioptic neuritis is a term used to describe noninfectious inflammatory disorders of the optic nerve sheaths, the causes of which are unknown. In the following report, a 68-year-old woman with bilateral visual loss was found to have chronic inflammation with necrobiotic granulomas of her optic nerve sheaths. The patient, who had no systemic condition known to be associated with necrobiotic granuloma, lost vision from infarction of the optic nerve parenchyma and from compression due to thickened meninges. Although there are similarities between the inflammatory reaction in this case to the necrobiotic dermatoses, the pathogenesis of this condition remains obscure.  相似文献   
74.
PURPOSE: This study was designed to identify risk indicators for the prevalence at enrollment and incidence over 36 months of periodontal pathology and coronal caries experience affecting third molars in a community-based study of people over 65 years of age. SUBJECTS AND METHODS: Data from a subsample of 810 dentate subjects from the Piedmont 65+ Study were available for analyses. All visible teeth were examined. Periodontal probing measures were taken at 2 sites, mesiobuccal and buccal/facial. Clinical data on caries experience were collected by visual-tactile examination. At enrollment, 340 subjects had at least 1 visible third molar; all were examined for caries experience. Periodontal probing measures were available for 277 of these same subjects. The significance of the possible risk indicators for periodontal pathology and caries affecting third molars was determined by chi(2) tests. Statistical significance was set at .05. Logistic multivariable models were used to derive odds ratios and 95% confidence intervals. RESULTS: African-American subjects were more likely to have visible third molars (P < .01). Caucasian subjects were more likely to have third molar coronal caries experience (P < .01), as were subjects with greater than a high school education and those with a dental visit within 3 years (both P < .01). However, African American subjects were more likely to have periodontal pathology, CALs >/= 3 mm on third molars (P < .01), as were those who used tobacco (P < .01). None of the other risk indicators we studied were associated with progression of periodontal pathology or coronal caries experience on visible third molars. CONCLUSION: In this population study of senior adults, Caucasians and African Americans appear to have different levels of risk for caries experience and periodontal pathology affecting retained third molars.  相似文献   
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Background: The attempts to explain the unpredictability of extent of spinal block provided by plain local anesthetic solutions have resulted in many clinical reports; however, causes of this uncertainty are as yet unknown. Recently, normal values of the human cerebrospinal fluid densities have been studied showing important interindividual variations, especially between females and males. The current study was designed to evaluate as primary endpoint the influence of cerebrospinal fluid density values on the extent of spinal block with plain bupivacaine. The ancillary endpoints were search of factors explaining the interindividual differences in cerebrospinal fluid density values reported and determination of the relation between upper extent and regression of spinal anesthesia.

Methods: Sixty-four consecutive patients undergoing peripheral orthopedic surgery with spinal block were enrolled. Spinal anesthesia was performed in the lateral decubitus position with the operated side upward. Two milliliters of cerebrospinal fluid was sampled before injection of 3 ml plain bupivacaine 0.5%. The patient was immediately turned supine and remained in the horizontal position until the end of the study. Maximal sensory block level and time to sensory regression to L4 were determined for each patient enrolled. Cerebrospinal fluid and bupivacaine densities as well as cerebrospinal proteins, glucose, sodium, and chloride concentrations were measured.

Results: A highly significant correlation between cerebrospinal fluid density and maximal sensory block level was found (P = 0.0004). However, this correlation was poorly predictive (R2 = 0.37). Cerebrospinal fluid density, proteins, and glucose concentrations were significantly higher in men than in women: 1.000567 +/- 0.000091 versus 1.000501 +/- 0.000109 g/ml (P = 0.014), 0.46 +/- 0.18 versus 0.32 +/- 0.13 g/l (P = 0.001), and 3.27 +/- 0.7 versus 2.93 +/- 0.5 mm (P = 0.023), respectively. A highly significant (P = 0.0004) and predictive (R2 = 0.73) inverse correlation was found between maximal upper sensory extent and sensory regression to L4.  相似文献   

78.
S Brett  J M Orrell  J Swanson Beck    J Ivanyi 《Immunology》1992,76(1):129-132
Mice infected by intraperitoneal injection of Mycobacterium tuberculosis were studied over a 23-week period. They showed progressive infection in the lung (with increasing microbial count and granuloma size) whereas viable bacillary counts remained largely stationary in the spleen and in the liver. The influence of H-2 genes on the progression of the lung infection was studied in four congenic strains of animals with B10 and three congenic strains of animals with BALB backgrounds. H-2k mice had significantly higher bacterial counts in the lung than H-2b mice on both B10 and BALB backgrounds, BALB. K (H-2k) mice were also more susceptible than BALB/c (H-2d) mice. Results with recombinant strains showed that bacillary counts and granulomatous infiltration were lower in the B10 (KbAbE-Db) compared with B10.A(3R) (KbAbEbDd) strain and in B10.A(4R) (KkAkE-Db) compared with B10.BR (KkAkEkDk) mice. This resistance to the late expansion of tuberculous infection in the lungs may be associated with the lack of an expressed I-E molecular or with the expression of the Db molecule.  相似文献   
79.
OBJECTIVE: To describe pelvic sonographic findings in girls as old as 7 years, to compare prepubertal girls with girls who had isolated thelarche or central precocious puberty, and to verify the accuracy of sonographic variables for distinguishing prepubertal girls from girls with central precocious puberty. METHODS: Ninety-six prepubertal girls and 2 reference groups (8 girls with isolated thelarche and 8 with idiopathic central precocious puberty) were included. Ovaries were classified morphologically as homogeneous, paucicystic, macrocystic, multicystic, and having isolated cysts. Receiver operating characteristic curves were used to choose the best cutoff points. RESULTS: Chronologic and bone age were correlated with uterine length, area, and volume and ovarian volume in prepubertal girls (P < .0001). Ovarian morphologic characteristics in prepubertal girls differed significantly from those of the reference groups (P < .0001). The best cutoff points were uterine length of 4.0 cm, uterine area of 4.5 cm2, uterine volume of 3.0 cm3, and ovarian volume of 1.0 cm3. CONCLUSIONS: Uterine and ovarian growth are proportional to age in prepubertal girls. Mean ovarian volume greater than 1 cm3 showed 100% sensitivity and specificity for discriminating between prepubertal girls and girls with central precocious puberty. Microcysts are common in prepubertal girls, but the presence of 6 or more follicles up to 10 mm in diameter may suggest central precocious puberty in girls younger than 8 years.  相似文献   
80.
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