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71.
72.
J Wechsler R Willemze A van der Brule E Thomine P Joly O Verola Y Fonck P Souteyrand MH Delfau M Bagot P Gaulard 《Canadian Metallurgical Quarterly》1998,134(4):479-484
OBJECTIVE: The aim of this investigation was to report on the radiographic interpretation of the hard palate and nasal fossa floor in panoramic radiographs by studying different skulls, x-ray machines, and head positions in relationship to the Frankfort plane before and after ostectomy. STUDY DESIGN: Twenty dry human skulls were radiographed with three different panoramic x-ray machines in three different positions. Three of the skulls were submitted to different ostectomies. RESULTS: Multiple images of the hard palate and nasal fossa floor were present in 96.12% of the radiographs. Single images (3.88%) occurred only in the "chin up" position. CONCLUSIONS: The lower image represents the nasal fossa floor, especially its lateral and anterior limits. The upper images are double real images mainly formed by the junction of the nasal septum with the nasal fossa floor and possibly by posterior parts of the hard palate and nasal fossa floor. All images overlap in the "chin up" position becoming a single image. The most common shape of the anatomic landmark was wide angle "W" (58.33%). Other shapes present in positions "chin up" and "chin down" indicate patient positioning errors. The x-ray machines did not influence the results. 相似文献
73.
BJ van Vlijmen NJ Pearce M Berg? B Staels JW Yates AD Gribble BC Bond MH Hofker LM Havekes PH Groot 《Canadian Metallurgical Quarterly》1998,48(4):396-402
PURPOSE: We report an investigation into the distribution of proteoglycans (PGs) in normal, organ-cultured and dextran-treated human corneas. METHODS: Immunogold labeling was carried out at the electron microscope level to localize keratan sulphate (KS), chondroitin sulphate (CS), and heparan sulphate (HS) PGs. RESULTS: High levels of labeling for CS was found in the epithelium, endothelium, and keratocytes, with light labelling present in the basement membranes and the corneal stroma. Labeling for HS was present in the epithelium, endothelium, and keratocytes, with intense labeling present at the endothelium/Descemet's membrane interface and the epithelium/Bowman's layer interface. Large filaments were also observed in these regions in cuprolinic blue-stained specimens. Keratan sulphate was present at high levels in the stroma and the basement membranes with low levels present within the keratocytes, epithelium, and endothelium. The pattern of KS labeling along the collagen fibrils in the stroma sometimes showed evidence of periodicity. Organ-cultured corneas had extensive collagen-free "lakes," the interior of which immunolabeled positively for KS and showed staining with cuprolinic blue. The lakes were greatly reduced in the dextran-treated samples. CONCLUSION: This investigation determined the ultrastructural distribution of KS, CS, and HS PGs in human cornea and showed that organ culture is associated with a change in distribution of stromal PGs. 相似文献
74.
SM Wang J Zwaan PB Mullaney MH Jabak A Al-Awad AH Beggs EC Engle 《Canadian Metallurgical Quarterly》1998,63(2):517-525
The extraocular fibrosis syndromes are congenital ocular-motility disorders that arise from dysfunction of the oculomotor, trochlear, and abducens nerves and/or the muscles that they innervate. Each is marked by a specific form of restrictive paralytic ophthalmoplegia with or without ptosis. Individuals with the classic form of congenital fibrosis of the extraocular muscles (CFEOM1) are born with bilateral ptosis and a restrictive infraductive external ophthalmoplegia. We previously demonstrated that CFEOM1 is caused by an autosomal dominant locus on chromosome 12 and results from a developmental absence of the superior division of the oculomotor nerve. We now have mapped a variant of CFEOM, exotropic strabismus fixus ("CFEOM2"). Affected individuals are born with bilateral ptosis and restrictive ophthalmoplegia with the globes "frozen" in extreme abduction. This autosomal recessive disorder is present in members of three consanguineous Saudi Arabian families. Genetic analysis of 70 individuals (20 affected individuals) reveals linkage to markers on chromosome 11q13, with a combined LOD score of 12.3 at the single nonrecombinant marker, D11S1314. The 2.5-cM CFEOM2 critical region is flanked by D11S4196/D11S4162 and D11S4184/1369. Two of the three families share a common disease-associated haplotype, suggesting a founder effect for CFEOM2. We hypothesize that CFEOM2 results from an analogous developmental defect to CFEOM1, one that affects both the superior and inferior divisions of the oculomotor nerve and their corresponding alpha motoneurons and extraocular muscles. 相似文献
75.
beta-N-Acetylhexosaminidase was purified from the extract of cabbage by sequential steps of ammonium sulfate fractionation, chromatofocusing, DEAE-Sepharose CL-6B ion exchange chromatography and Sephacryl S-200 HR gel filtration. By these steps, the purity of the enzyme increased by 256 fold with a recovery of 8%. The purified enzyme was homogeneous as examined by native PAGE. It showed an optimal pH of 4, an optimal temperature of 60 degrees C and a Km of 0.94 mM for hydrolysis of pNp-beta-GlcNAc. The molecular mass of the enzyme determined from filtration through Sephacryl S-200 was 150 kDa. Three subunits with molecular mass of 64, 57 and 51 kDa were observed as determined by SDS-PAGE. NBS (0.025 mM), DEPC (3 mM) and WRK (30 mM) significantly inhibited the activity of the enzyme. The enzyme also showed activity toward pNp-beta-GalNAc, N,N'-diacetylchitobiose, N,N',N"-triacetylchitotriose and N,N',N",N"'-tetraacetyl chitotetraose but showed no activity toward pNp-alpha-GlcNAc, chitin and ethylene glycol chitin. 相似文献
76.
MH Seegenschmiedt L Keilholz A Stecken A Katalinic R Sauer 《Canadian Metallurgical Quarterly》1996,172(7):376-383
BACKGROUND: In a retrospective study the efficacy of orthovoltage radiotherapy for refractory painful plantar heel spur was analyzed for 3 different radiation dose concepts. PATIENTS AND METHODS: From 1.1 1984 through 1.3.1994, 182 patients with refractory painful heel symptoms and radiologically proven plantar heel spur received radiotherapy. A total of 141 patients and 170 heels (due to double-sided symptoms) were completely documented in long-term follow-up. Clearly defined semi-quantitative criteria (9-point score) were used to analyze heel pain and ankle function prior to RT, 6 to 12 weeks post-radiation, and at last follow-up. The treatment outcome, i.e. (un)favourable response, of 3 radiation dose concepts were compared: Group A (n = 72 heels) received 12 Gy total radiation dose in 3 fractions per week and 2 series (6 x 1 Gy per series) separated by 6 weeks; group B (n = 98 heels) received 3 Gy total radiation dose in 10 fractions of 0.3 Gy (n = 50) or 5 Gy (10 x 0.5 Gy) (n = 48) with conventional fractionation in 1 series. RESULTS: Radiotherapy was very effective: at last follow-up 67% (group A) and 71% (group B) remained completely free of pain. The rate of "complete pain relief" (i.e. free of any pain symptoms) was not different between the 3 radiation concepts. However, significant differences were observed with regard to "incomplete or insufficient pain relief", i.e. a subjective pain relief of less than 80%, a delayed pain relief after more than 4 weeks or a relapse of pain symptoms in long-term follow-up. More favourable results were achieved in patients receiving 5 Gy or 12 Gy total dose, while patients with 3 Gy total dose had significantly worse results. Prognostic factors for "complete pain relief" were short duration of pain symptoms and acute pain symptoms prior to radiotherapy; with regard to "in-complete or insufficient pain relief" the total dose was found to be a prognostic parameter. CONCLUSIONS: Patients with refractory heel pain can yield a high response to radiotherapy even after failing various conventional treatments previously. Thus, radiotherapy should not be solely regarded as a last resort due to its low costs and high efficacy at low radiation doses. 相似文献
77.
Since women with a first-degree relative with breast cancer are at increased risk for breast cancer, it is of special importance that they adhere to early detection programs. In this study, women with (389) and without (3295) a family history of breast cancer were compared with respect to risk perception, breast cancer anxiety, and early detection behavior. Special attention was paid to the role of knowing that family history is a breast cancer risk factor. It was found that 46% of "family history positives" did not know that their risk was increased by their family history. Still, family history positives had increased risk perception; our results suggest that this was partly caused by their knowing they belonged to a risk group and partly by their having experienced the disease at close range. Although family history positives had higher risk perceptions, no differences in early detection behavior were found. This could not be attributed to high anxiety levels. Implications for health education are discussed. 相似文献
78.
MA Bloomberg HS Jordan KO Angel MH Bailit KJ Goonan J Straus 《Canadian Metallurgical Quarterly》1993,19(12):586-595
This article describes a collaborative effort between a major health care purchaser, three area health maintenance organizations, and a state Medicaid agency to develop clinical indicators as the basis for a comparison database. Some of the difficulties in developing a "common yardstick" of quality and value are candidly discussed. 相似文献
79.
This study compared the effects of undiluted and 8% ethanol administered orally on gastrointestinal antioxidant components of male and female rats. Eight percent ethanol increased the activities of duodenal glutathione peroxide (29% in males, 14% in females) and superoxide dismutase in female gastric (24%) and male duodenal (15%) mucosa. This dose of ethanol also increased the glutathione content of gastric mucosa (12% in males, 13% in females). Undiluted ethanol decreased glutathione levels in gastric mucosa (22% in males, 11% in females) and increased glutathione peroxide activity in gastric mucosa (14% in males, 9% in females). Undiluted alcohol also produced decreases in the activity of glutathione reductase in stomach (14% in males, 9% in females) and duodenum (16% in males, 12% in females). Undiluted ethanol caused mucosal damage in the body of the stomach in both genders, accompanied by an increase in luminal pH and fluid accumulation in the stomach; these changes were absent in rats given 8% ethanol. The increase in gastrointestinal antioxidant capacity associated with the administration of 8% ethanol may be a factor in the reported cytoprotective effect of lower doses of ethanol. 相似文献
80.
MH Safir AE Gousse ES Rovner DA Ginsberg S Raz 《Canadian Metallurgical Quarterly》1999,161(2):587-594
PURPOSE: The 4-defect repair of grade 4 cystocele corrects discrete and severe deficiencies of vesicourethral support. We describe this technique used during pelvic reconstruction in 130 women. MATERIALS AND METHODS: During a 3-year period 130 patients (age range 35 to 96 years) underwent repair of grade 4 cystocele using the 4-defect repair technique. Cystocele repair had been performed in 60 patients (46%) and hysterectomy had been performed in 85 (65%). A "goalpost incision" is used in the vaginal wall to facilitate separation of the wall from underlying perivesical fascia, entry into the retropubic space, and exposure of the urethropelvic ligament, cardinal ligament and perivesical fascia. The 4 polypropylene sutures are used to provide an anterior vaginal wall sling which is modified to incorporate perivesical fascia and cardinal ligaments. Central defect repair is achieved by approximation of the cardinal ligaments and midline plication of the perivesical fascia over absorbable mesh. RESULTS: A total of 112 patients were available for followup which ranged from 6 to 42 months (mean 21). Repair of grade 4 cystocele was accompanied by other transvaginal repairs in 94 patients (83%), including rectocele repair in 81, hysterectomy in 22 and enterocele repair in 31. Of the patients 92% had excellent objective and subjective results for anatomical cystocele repair. Of the patients with preoperative stress urinary incontinence 90% had excellent or good subjective results. De novo urge incontinence was seen in 7% of patients. CONCLUSIONS: The 4-defect repair technique relies on anatomical restoration of 4 distinct deficiencies of pelvic support and is highly effective for relief of symptoms of grade 4 cystocele. 相似文献