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101.
The purpose of this article is to describe two cases of bilateral cleft lip and palate with natal/neonatal teeth. Clinical features, prevalence, possible complications, and treatment modalities are discussed. Two patients with cleft lip and palate and natal/neonatal teeth are described. The first patient was a 4-week-old infant with bilateral cleft lip and palate. On initial inspection an odontogenic vestige was noticed on the right lateral border of the premaxillary segment, bordering the cleft. The second patient was a newborn with a vestige on the right side of the premaxilla. At 20 days, another swelling representing a neonatal tooth on the left side was found. Because the teeth interfered with the fabrication and application of the nasoalveolar molding (NAM) appliance, they were removed from both patients. In the first patient, at 1 week after extraction, the NAM device was placed without difficulty. At 8 months, the infant had adapted well to the NAM device and nursed without problems. The second patient did not follow-up for the placement of the NAM device. In patients with cleft lip and palate with natal/neonatal teeth who require NAM, the tooth must be removed to facilitate the fabrication and placement of the device. Natal/neonatal teeth must be extracted with caution because the tooth buds of neighboring teeth may be damaged and remnants of the dental papillae may be left behind. Although general anesthesia is not always indicated for the removal of these teeth, in cases in which the premaxilla is loose, such as the current cases, general anesthesia is warranted.  相似文献   
102.
Hemodialysis patients are prone to deficiency of vitamin C, which constitutes the most abundant nonenzymatic antioxidant in blood. Because antioxidants are involved in the pathogenesis of atherosclerosis, the authors examined the association of total vitamin C plasma level with cardiovascular outcomes in such patients. One hundred thirty-eight consecutive maintenance hemodialysis patients (median age 61 yr, 90 males) were enrolled in a single-center study. At baseline, routine laboratory parameters were recorded, and predialysis total vitamin C plasma levels were measured by high-pressure liquid chromatography. Patients were prospectively followed-up for the occurrence of a primary composite endpoint consisting of fatal and nonfatal major adverse cardiovascular events (MACE) and for all-cause and cardiovascular mortality. MACE occurred in 35 patients (25%) over a period of median 30 mo, and 42 patients (30%) died [29 cardiovascular deaths (21% of total)]. Using Cox proportional hazards modeling, adjusted hazard ratios for the occurrence of MACE were 3.90 (95% confidence interval [CI]: 1.42 to 10.67; P = 0.008) and 3.03 (95% CI: 1.03 to 8.92; P = 0.044) for patients in the lower (<32 micromol/L) and middle (32 to 60 micromol/L) tertile of total vitamin C levels, compared with patients in the upper tertile (>60 micromol/L). Hazard ratios for cardiovascular death were 3.79 (95% CI: 1.23 to 11.66; P = 0.020) and 2.89 (95% CI: 0.89 to 9.37; P = 0.076). Total vitamin C levels were not independently associated with all-cause mortality. This study concludes that low total vitamin C plasma levels predict adverse cardiovascular outcomes among maintenance hemodialysis patients. Future studies should address the potential protective effect of an adequate vitamin C supplementation.  相似文献   
103.
BACKGROUND: Small, unrandomized studies have indicated that pharmacologically induced blood pressure elevation may improve function in ischemic stroke, presumably by improving blood flow to ischemic, but noninfarcted tissue (which may be indicated by diffusion-perfusion mismatch on MRI). We conducted a pilot, randomized trial to evaluate effects of pharmacologically induced blood pressure elevation on function and perfusion in acute stroke. METHODS: Consecutive series of patients with large diffusion-perfusion mismatch were randomly assigned to induced blood pressure elevation ('treated' patients, n = 9) or conventional management ('untreated' patients, n = 6). RESULTS: There were no significant differences between groups at baseline. NIH Stroke Scale (NIHSS) scores were lower (better) in treated versus untreated patients at day 3 (mean 5.6 vs. 12.3; p = 0.01) and week 6-8 (mean 2.8 vs. 9.7; p < 0.04). Treated (but not untreated) patients showed significant improvement from day 1 to day 3 in NIHSS score (from mean 10.2 to 5.6; p < 0.002), cognitive score (from mean 58.7 to 27.9% errors; p < 0.002), and volume of hypoperfused tissue (mean 132 to 58 ml; p < 0.02). High Pearson correlations between the mean arterial pressure (MAP) and accuracy on daily cognitive tests indicated that functional changes were due to changes in MAP. CONCLUSION: Results warrant a full-scale, double-blind clinical trial to evaluate the efficacy and risk of induced blood pressure elevation in selective patients with acute/subacute stroke.  相似文献   
104.
PURPOSE: In this research ACE activity (as a marker of epithelial injury) was studied in rats with gentamicin induced renal toxicity. METHODS: Male Sprague-Dawley rats were sacrificed 1, 3, 5, and 7 days after gentamicin injection, 100 mg/kg/day for 1, 3, 5, and 7 consecutive days. ACE activity was measured in serum, kidney and lung. These data were compared with normal saline-treated rats. Histological scoring of renal cortical pathology was performed on days 1, 3, 5, and 7. RESULTS: Treatment of rats with gentamicin resulted in renal damage evidenced by proteinuria, polyuria, and decreased creatinine clearance. The damage to the kidney proximal tubule was evident by (a) the histological analysis at light microscopy and (b) the augmentation in the urinary excretion of N-acetyl-beta-D-glucosaminidase (NAG). Kidney ACE activity decreased while lung and serum ACE activity didn't change until day 7. Lung ACE activity increased significantly on day 7. Kidney and serum ACE activity increased too. Blood pressure increased significantly on day 7. This corresponded well with the lung ACE activity increment. CONCLUSION: These data suggest that kidney ACE activity decreased significantly just one day after gentamicin administration and prior to kidney NAG decrease.  相似文献   
105.
PURPOSE: To evaluate a screening protocol for detection of individuals with a higher risk of chronic open angle glaucoma for which a complete glaucoma evaluation is indicated. PATIENTS AND METHODS: African Americans over 40 years of age in New Haven, CT. In the screening phase, volunteers filled out a questionnaire and underwent measurements of visual acuity, intraocular pressure (IOP) with a Tono-Pen and visual field with Frequency Doubling Technology. Participants were categorized into "glaucoma likely" or "unlikely," but all were encouraged to follow up with a free complete glaucoma exam, which included applanation tonometry, pachymetry, visual fields with a Humphrey Visual Field Analyzer, gonioscopy, and fundoscopy. Based on the latter exam, patients were categorized into "glaucoma likely" (suspects and confirmed glaucoma) or "unlikely" groups. RESULTS: One hundred eighty-four subjects completed both phases of the study and 76 of 93 patients (82%) who were classified as "glaucoma likely" in the final exam, were also classified as "glaucoma likely" in the screening. Adjusted analysis revealed family history of glaucoma in first degree relatives and screening IOP > 21 mm Hg to have statistically significant associations with the final impression of "glaucoma likely." A combination of these findings gave an overall sensitivity of 81.7% with a specificity of 55%. CONCLUSIONS: In the study population, the combination of an IOP > 21 mm Hg and history of glaucoma in a first degree relative allowed the identification of a significant percentage of individuals with a higher risk of chronic open angle glaucoma, for which a complete glaucoma examination is indicated.  相似文献   
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109.
In the past decade, potential pathogens, including Alcaligenes species, have been increasingly recovered from cystic fibrosis (CF) patients. Accurate identification of multiply antibiotic-resistant gram-negative bacilli is critical to understanding the epidemiology and clinical implications of emerging pathogens in CF. We examined the frequency of correct identification of Alcaligenes spp. by microbiology laboratories affiliated with American CF patient care centers. Selective media, an exotoxin A probe for Pseudomonas aeruginosa, and a commercial identification assay, API 20 NE, were used for identification. The activity of antimicrobial agents against these clinical isolates was determined. A total of 106 strains from 78 patients from 49 CF centers in 22 states were studied. Most (89%) were correctly identified by the referring laboratories as Alcaligenes xylosoxidans. However, 12 (11%) strains were misidentified; these were found to be P. aeruginosa (n = 10), Stenotrophomonas maltophilia (n = 1), and Burkholderia cepacia (n = 1). Minocycline, imipenem, meropenem, piperacillin, and piperacillin-tazobactam were the most active since 51, 59, 51, 50, and 55% of strains, respectively, were inhibited. High concentrations of colistin (100 and 200 microg/ml) inhibited 92% of strains. Chloramphenicol paired with minocycline and ciprofloxacin paired with either imipenem or meropenem were the most active combinations and inhibited 40 and 32%, respectively, of strains. Selective media and biochemical identification proved to be useful strategies for distinguishing A. xylosoxidans from other CF pathogens. Standards for processing CF specimens should be developed, and the optimal method for antimicrobial susceptibility testing of A. xylosoxidans should be determined.  相似文献   
110.
PURPOSE: To perform a mutation screening of TACSTD2 in 13 Iranian Gelatinous Drop-like Corneal Dystrophy (GDLD) pedigrees. To assess genotype-phenotype correlations. To determine intragenic SNP haplotypes associated with the mutations, so as to gain information on their origin. METHODS: The coding region of TACSTD2 was sequenced in the probands of 13 unrelated Iranian GDLD pedigrees. Variations were assessed in other available affected and unaffected family members and in unrelated normal control subjects by restriction fragment length polymorphism (RFLP). The variations were classified as being associated with disease if they segregated with the disease phenotype in the families, were not observed in 100 control individuals, disrupted protein expression, or affected conserved positions in the coded protein. Three intragenic single-nucleotide polymorphisms (SNPs) were used to define haplotypes associated with putative disease-causing mutations. RESULTS: The probands were each homozygous for one of four putative disease-causing variations observed in TACSTD2: C66X, F114C, L186P, and E227K. Three of these are novel. E227K was found in 10 of the Iranian patients. There were some phenotypic differences among different patients carrying this mutation-for example, with respect to age at onset. Genotyping of intragenic SNPs identified four haplotypes. C66X, F114C, and L186P were each associated with a haplotype common among control chromosomes, whereas all E227K alleles were associated with a haplotype not found among the control chromosomes. CONCLUSIONS: Although mutations in TACSTD2 among Iranian patients with GDLD were heterogeneous, E227K was found to be a common mutation. It is suggested that E227K may be a founder mutation in this population. Based on positions of known mutations in TACSTD2, significance of the thyroglobulin domain of the TACSTD2 protein in the pathogenesis of GDLD is suggested.  相似文献   
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