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991.
The moisture sorption and desorption profiles of four different viscosity grades of (hydroxypropyl)methylcellulose (HPMC) 2208 (HPMC K100, HPMC K4M, HPMC K15M, and HPMC K100M) of different particle size fractions were analyzed according to the Young and Nelson equations. These equations describe three locations of the sorbed moisture: monolayer adsorption, externally adsorbed moisture, and internally absorbed moisture. The effects of particle size and viscosity grade of HPMC on the three locations of moisture showed that an increase in particle size generally resulted in a reduction in the amount of internal absorption and an increase in the amount of external adsorption. These changes were more apparent for HPMC K100 and HPMC K4M than for the higher viscosity grades. The lowest values of internally absorbed moisture were obtained for HPMC K100M. Changes in tensile strengths, mean yield pressures, and elastic recoveries of HPMC K4M tablets were explained in terms of the changes produced in the internally absorbed moisture and the externally adsorbed moisture. The amounts of nonfreezing and freezing water in samples exposed to moisture were determined from melting endotherms obtained by differential scanning calorimetry. Increases in the water:HPMC ratio resulted in increases in the enthalpies of water melting for the four viscosity grades of HPMC for the < 45 and 250-350 microns particle size fractions. The amount of nonfreezable water was unaffected by change in viscosity grade or particle size. 相似文献
992.
We report a 15-year-old girl with a 10-year-old history of typical skin features of dermatomyositis (DM) without evidence of muscle involvement. Amyopathic dermatomyositis (ADM) is defined by the presence of biopsy confirmed classic cutaneous findings of dermatomyositis in the absence of any clinical or laboratory signs of muscle disease for at least 2 years after onset of skin pathology. To exclude muscle involvement muscle enzymes should be normal; moreover additional use of magnetic resonance imaging and muscle ultrasound is currently being proposed. It is as yet undetermined, whether early aggressive immunosuppressive treatment of ADM might prevent the development of myositis at a later date or influence the course of the skin disease. In a paediatric patient with ADM we advocate a more expectant attitude with careful and regular monitoring for possible development of muscle disease. 相似文献
993.
994.
STUDY DESIGN: A case of severe postoperative angioedema after excision of cervical osteophyte is presented. Emergent tracheostomy was required. OBJECTIVES: To discuss the etiologies, diagnosis, and management of this unusual cause of acute respiratory distress after an anterior cervical spinous procedure. SUMMARY OF BACKGROUND DATA: To our knowledge, angioedema as a complication of cervical spine surgery has not been reported previously. The patient had no history of angioedema, was not receiving an acetyl choline esterase inhibitor, and had a normal C1-esterase-inhibitor level. METHODS: The patient was a 61-year-old man with ankylosing spondylitis who, because of progressive dysphagia and choking episodes, underwent excision of a large C3-C4 osteophyte and anterior cervical discectomy and fusion. While in the postanesthesia care unit, the patient experienced massive edema of the tongue and neck, with associated difficulty breathing. Reexploration of the wound revealed a small (30 cc) hematoma, which was removed with no obvious benefit to the patient, who ultimately required a tracheotomy. RESULTS: The patient was managed with intravenous corticosteroids. The tracheotomy tube was removed without incident after 7 days. The patient noted decreased neck pain and dramatic improvement in his ability to swallow postoperatively. He has had no further incidents of angioedema, to date. CONCLUSION: Angioedema should be considered in the differential diagnosis in patients with upper extremity respiratory obstruction after anterior surgery of the cervical spine. 相似文献
995.
996.
The boundary element method is well adjusted to the numerical resolution of thermal diffusion problems existing in complex volumes such as teeth. This technique is used to determine the temperatures in the bulk and on the surface of a tooth illuminated by a CO2 laser beam. The parameters taken into account in calculations include power absorbed by the tooth, laser irradiation time, and diameter of the beam on the tooth. In each case, a very fast and short heating period is observed on the tooth surface; then, the temperature decreases slowly. Inside the tooth, temperature variations are small or nonexistent. Temperature increases due to a laser beam remain concentrated at the impact region. Results are in reasonable agreement with experimental results. 相似文献
997.
MH Wansbrough-Jones E Frimpong B Cant K Harris MR Evans CG Teo 《Canadian Metallurgical Quarterly》1998,92(5):496-499
BACKGROUND: Short stature is one of the features of Turner syndrome and a form of presentation of monosymptomatic celiac disease. METHODS: The recognition of celiac disease in two antiendomysium antibody-positive Turner syndrome girls who did not respond to growth hormone treatment led us to perform as a screening for celiac disease IgA and IgG antigliadin antibodies and antiendomysium antibodies determination in other 35 Turner syndrome patients. Intestinal biopsy was proposed to the antiendomysium antibodies-positive girls; in the former, subtotal villous atrophy was found; in the latter, one parent's consent for intestinal biopsy was not obtained. RESULTS: The prevalence of celiac disease in Turner syndrome patients observed in the present study (8.1 if we consider 3 villous atrophy, 10.8 if we consider 4 antiendomysium antibody-positive) is quite high and seems to indicate that the association of these two disorders could not be coincidental. As to the clinical picture, celiac disease appeared atypical in one case, typical in another one and as a silent form in the third case. Of the 3 cases with villous atrophy on gluten-free diet growth hormone therapy was not effective in two girls, who were older than 16 years, while in the younger patient, detected by the screening, a significant increment of height velocity and height Standard Deviation Score for Chronological Age according to Turner references was observed. CONCLUSIONS: This study suggests that celiac disease can be associated with Turner syndrome and even responsible for a failure of growth hormone therapy. Therefore we propose to perform in Turner syndrome patients antiendomysium antibody determination as a screening followed by intestinal biopsy in positive cases. This would be advisable at least before starting growth hormone treatment. 相似文献
998.
JW Ramos TK Kojima PE Hughes CA Fenczik MH Ginsberg 《Canadian Metallurgical Quarterly》1998,273(51):33897-33900
Increased integrin ligand binding affinity (activation) is triggered by intracellular signaling events. A Ras-initiated mitogen-activated protein kinase pathway suppresses integrin activation in fibroblasts. We used expression cloning to isolate cDNAs that prevent Ras suppression of integrin activation. Here, we report that PEA-15, a small death effector domain (DED)-containing protein, blocks Ras suppression. PEA-15 does not block the capacity of Ras to activate the ERK mitogen-activated protein kinase pathway. Instead, it inhibits suppression via a pathway blocked by a dominant-negative form of the distinct small GTPase, R-Ras. Heretofore, all known DEDs functioned in the regulation of apoptosis. In contrast, the DED of PEA-15 is essential for its capacity to reverse suppression of integrin activation. Thus, certain DED-containing proteins can regulate integrin activation as opposed to apoptotic protease cascades. 相似文献
999.
Our objectives were to determine the reproducibility, or interobserver agreement, of transvaginal sonographic imaging of the uterus in patients with abnormal uterine bleeding and to identify the effect of observer experience. Transvaginal ultrasound findings of 235 patients with abnormal uterine bleeding were recorded systematically on videotape. Recordings were reviewed by three observers who had different levels of experience, and who were asked to judge the endometrium/uterine cavity and myometrium separately as being normal, abnormal or inconclusive, according to predefined criteria. Reproducibility was expressed by the observed rates of interobserver agreement and by kappa statistics. The differences in agreement between observer pairs were analyzed by means of McNemar's chi 2 test. The observed rates of agreement for the judgement of the endometrium/uterine cavity varied from 0.85 to 0.89, with a kappa value ranging from 0.70 to 0.78 between observers. The judgment of the myometrium resulted in agreement rates of 0.86-0.91 and kappa values of 0.67-0.80. Although the effect of experience was evident, the differences in agreement between observers were not significant (p > 0.01). The reproducibility of the results of transvaginal sonography of the uterus in patients with abnormal uterine bleeding was good. Observations of the endometrium/ uterine cavity with a normal appearance were the most highly reproducible, with the smallest effect of observer experience. This may reduce the need for invasive diagnostic procedures in patients with abnormal uterine bleeding. 相似文献
1000.
MH Johnson 《Canadian Metallurgical Quarterly》1998,8(1):119-141
Conventional computed tomography (CT) and magnetic resonance (MR) angiography provide excellent vascular images; however, every radiologist interpreting routine cross-sectional imaging of the head and neck must recognize normal and abnormal vascular structures. Knowledge of the normal cross-sectional appearance of vessels can help to define spacial anatomy and provide for recognition of abnormal vessels. Intracranially, the major arterial branches of the Circle of Willis are routinely visualized on MR and CT, as are the dural venous sinuses and major tributaries to the deep and superficial venous system. Using a combination of CT and MR images, we demonstrate the normal cross-sectional vascular anatomy of the head and neck and the important anatomic relationships key to accurate imaging analysis. 相似文献