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991.
FB Demirkazik O Ba?kan U Ayding?z T Tacal P Firat 《Canadian Metallurgical Quarterly》1996,69(823):678-680
An extremely rare case of metastatic squamous cell skin carcinoma to the breast is reported with imaging features. Ultrasonography and magnetic resonance imaging revealed well circumscribed, complex solid masses with papillary fronds projecting into cystic centres. 相似文献
992.
BACKGROUND: Airway obstruction after anesthesia may be caused or exaggerated by residual neuromuscular block, with loss of muscle support for collapsible upper airway structures. METHODS: Six male volunteers were studied before treatment, during stable partial neuromuscular block with vecuronium at a mean train-of-four (TOF) ratio of 50% (95% CI, 36-61%), and after reversal by neostigmine. Catheter-mounted transducers were placed in the pharynx and esophagus to estimate, respectively, the upper airway resistance, and the work of breathing (calculated as the time integral of the inspiratory pressure developed by the respiratory muscles, esophageal pressure time product) during quiet breathing, during breathing 5% carbon dioxide, and while breathing with an inspiratory resistor. Breathing with pressure at the airway opening held at pressures from -5 to 40 cm H2O were also tested to assess airway collapsibility. RESULTS: Although breathing through a resistor increased upper airway resistance from 1.2 (0.67, 1.72) cm H2O x l(-1) x s to 2.5 (1.32, 3.38) cm H2O x l(-1) x s, and carbon dioxide stimulation reduced resistance to 0.8 (0.46, 1.33) cm H2O x l(-1) x s, no effect of partial neuromuscular block (mean TOF ratio, 52%) on upper airway properties could be shown. CONCLUSIONS: Neuromuscular block with a TOF ratio of 50% can be present yet clinically difficult to detect in patients recovering from anesthesia. This degree of block has no effect on airway patency in volunteers, even during challenge. Airway obstruction during recovery from anesthesia thus is more likely to be caused by residual effects of general anesthetic agents or centrally acting analgesics, either alone or perhaps in concert with residual neuromuscular block. 相似文献
993.
ML Grayson GW Gibbons GM Habershaw DV Freeman FB Pomposelli BI Rosenblum E Levin AW Karchmer 《Canadian Metallurgical Quarterly》1994,18(5):683-693
In a double-blind randomized trial, imipenem/cilastatin (I/C; 500 mg every 6 hours) and ampicillin/sulbactam (A/S; 3 g every 6 hours) were compared in regard to their efficacy for initial empirical and definitive parenteral treatment of limb-threatening pedal infection in diabetic patients. The major endpoints of treatment were cure (resolution of soft-tissue infection), failure (inadequate improvement, necessitating a change in antibiotic therapy), and eradication (clearance of all pathogens from the wound and any bone cultures). Patients in the two treatment groups were similar in regard to the severity of diabetes; presence of neuropathy and peripheral vascular disease; site and severity of infection; pathogen isolated; and frequency of osteomyelitis (associated with 68% of the 48 A/S-treated infections and 56% of the 48 I/C-treated infections). After 5 days of empirical treatment, improvement was noted in 94% of the A/S and 98% of the I/C recipients. At the end of definitive treatment (days' duration [mean +/- SD]: 13 +/- 6.5 [A/S], 14.8 +/- 8.6 [I/C]), outcomes were similar: cure, 81% (A/S) vs. 85% (I/C); failure, 17% (A/S) vs. 13% (I/C); and eradication, 67% (A/S) vs. 75% (I/C). Treatment failures were associated with the presence of antibiotic-resistant pathogens and possible nosocomial acquisition of infections. The number of adverse events among patients in the two treatment groups was similar: 7 in the A/S group (4 had diarrhea and 3 had rash) and 9 in the I/C group (5 had diarrhea, 2 had severe nausea, 1 had rash, and 1 had seizure). Efficacy of A/S and I/C is similar for initial empirical and definitive treatment of limb-threatening pedal infection in patients with diabetes. 相似文献
994.
J Huston DA Nichols PH Luetmer CH Rydberg BD Lewis FB Meyer RD Brown CD Schleck 《Canadian Metallurgical Quarterly》1998,19(2):309-315
This study describes a HPLC method to determine the concentrations of acetylsalicylic acid (ASA) and salicylic acid (SA) in human stratum corneum and in plasma. The stratum corneum layers for ASA/SA analysis were removed from three patients with postherpetic hyperalgesia treated with topical and oral aspirin. Blood samples were also collected from the same patients. Tape strippings were placed in acetonitrile and sonicated for 15 min. After centrifuging, aliquots of the supernatant were injected into the chromatograph. ASA and SA from plasma samples were extracted on Isolute C8 columns. Due to interfering peaks in the tape samples, HPLC conditions were slightly different for tape and plasma samples. ASA and SA were separated on a LiChrospher 100 RP-18 column at 1 ml/min using a water-phosphate buffer (pH 2.5)-acetonitrile mobile phase (35:40:25, v/v/v). A linear response to quantities of ASA from 0.1 to 100 microg/cm2 and of SA from 0.1 to 5 microg/cm2 in tape and to quantities of ASA 0.1 to 2 microg/ml and 1 to 50 microg/ml was obtained and the recovery from tape and plasma samples was over 98%. The method is sensitive (0.1 microg/cm2) and specific enough to allow the determination of the drugs in the skin not only after topical but also after oral administration. A good sensitivity was also obtained in plasma (0.1 microg/ml) allowing study of the kinetics of ASA and SA in plasma after oral administration. Concentrations of ASA after topical administration were 100-200 times higher than after oral administration. Plasma levels of ASA and SA after oral administration were similar to those previously found. No ASA or SA were detected in plasma after topical ASA administration. 相似文献
995.
Atkins G.R. Zhen Hua Wang McKenzie D.R. Sceats M.G. Poole S.B. Simmons H.W. 《Lightwave Technology, Journal of》1993,11(11):1793-1801
Cathodoluminescence spectra of germanosilicate and silicate glass in modified chemical vapor deposition (MCVD) and vapor-phase axial deposition (VAD) preforms are presented, and the influence of co-doping with phosphorus, boron, and fluorine on the peaks associated with the E' and the so-called drawing-induced defects are studied. A simple reaction scheme is developed which illustrates that these defects can be controlled by the electron donor (P) and scavenger (B,F) properties of the co-dopant 相似文献
996.
LM Sancho MS Paschoalini A Fernandez C Higutchi FB Jatene 《Canadian Metallurgical Quarterly》1997,52(5):254-257
The authors analysed a group of patients with lung abscesses that received surgical treatment, as well as the characteristics of their evolution. Seventeen patients with lung abscesses which underwent surgical therapy from 1984 to 1995 were analysed. The group was composed of 12 male and 5 female. The age varied from 25 to 78 years (mean-50.1 years). The etiologies were: post-pneumonic, tuberculosis, foreign-body, empyema. Two types of surgical procedures were performed: pulmonary resection and transthoracic drainage. The indication of surgery was based on the failure of clinical treatment, massive hemoptysis, pleural empyema and residual cavity wider than 2 cm after 6 weeks of clinical treatment. The patients with poor clinical conditions were selected to transthoracic drainage, the less invasive procedure. Most patients had a satisfactory post-operative evolution (58.9%). Five patients had complications (29.4%) as empyema and air leak for more than three weeks and two patients died (11.9%). Regarding the surgical technics, the pulmonary resection (lobectomy and segmentectomy) showed no morbidity and mortality. The usage of external chest tube drainage of the abscess had a morbidity of 40% and mortality of 20%. In conclusion, the complicated lung abscess is still a surgical pathology and the best approach seems to be the resection of the pulmonary segment affected. The drainage has specific indication, mainly in patients with deteriorating condition, but this procedure has high mortality and morbidity rates. 相似文献
997.
AJ Czaja F Cassani M Cataleta P Valentini FB Bianchi 《Canadian Metallurgical Quarterly》1997,42(8):1688-1696
To determine the significance of antinuclear antibodies and their patterns of indirect immunofluorescence in type 1 autoimmune hepatitis, sera from 99 patients were evaluated. Patients with antinuclear antibodies had a lower frequency of liver transplantation (6% vs 22%, P = 0.04) than seronegative patients. They were also more commonly HLA-DR4-positive than seronegative patients (56% vs 30%, P = 0.05) and normal subjects (56% vs 30%, P = 0.004). The 42 patients with antinuclear antibodies and a diffuse pattern of indirect immunofluorescence had higher serum titers of ANA (serum titers > or = 1:500, 71% vs 14%, P < 0.0001) and SMA (serum titers > or = 1:500, 69% vs 27%, P = 0.003) than the 22 patients with antinuclear antibodies and a speckled pattern. These patients, however, were otherwise not distinguished by clinical features and treatment response. Patients with a speckled pattern had A1-B8-DR3 more frequently than patients with a diffuse pattern (65% vs 23%, P = 0.005) and normal subjects (65% vs 13%, P < 0.0001), but they had no other salient features. We conclude that patients with antinuclear antibodies have a better long-term prognosis than seronegative patients, and they have HLA-DR4 more commonly. The patterns of indirect immunofluorescence associated with ANA positivity have no practical clinical implications. 相似文献
998.
DA Nichols RD Brown KR Thielen FB Meyer JL Atkinson DG Piepgras 《Canadian Metallurgical Quarterly》1997,87(3):374-380
The murine interleukin-7 (IL-7) gene was disrupted to examine the role of IL-7 in the lymphoid system. Expansion of lymphoid cells is sharply curtailed in IL-7-deficient mice. This is evident in a dramatic reduction but not elimination of lymphoid cells in the thymus, bone marrow and spleen. The few thymocytes present express CD4 and/or CD8 markers associated with T-cell maturation. Similarly, a limited number of B cells detected in the bone marrow rearrange and express immunoglobulin genes. Small but distinct populations of B and T cells are found in the spleens of IL-7-deficient mice. Thus the signal transmitted by IL-7 plays a central role in the expansion of lymphocytes while it is not absolutely required for their maturation. A transgene that directs expression of IL-7 to lymphoid cells was found to restore the numbers of thymocytes, bone marrow B-cell progenitors and splenic lymphocytes of IL-7-deficient mice to approximately normal levels. This genetic complementation confirms that the lymphoid defect is specifically due to the absence of IL-7 and demonstrates that the expansion of lymphoid cells in an organism is regulated by their exposure to IL-7. 相似文献
999.
A Campbell I Chanal W Czarlewski FB Michel J Bousquet 《Canadian Metallurgical Quarterly》1997,52(10):1022-1025
ICAM-1, a transmembrane glycoprotein promoting adhesion in immunologic and inflammatory reactions, was found to be increased on nasal epithelial cells of patients with allergic rhinitis. Loratadine, an H1-blocker, was found to reduce in vitro the expression of ICAM-1 on nasal epithelial cells. A double-blind, parallel-group study was carried out during the pollen season to compare the effect of two H1-blockers, cetirizine (10 mg OD) and loratadine (10 mg OD), on the release of soluble ICAM-1 in nasal secretions. A group of untreated patients was used as a control group. sICAM-1 was measured by enzyme immunoassay before and after 2 weeks of treatment. Symptoms were significantly decreased in the actively treated groups. sICAM-1 levels were unchanged in the control group but were significantly reduced in the two treated groups (P < 0.015, Wilcoxon's W test). This study shows that two H1-blockers, loratadine and cetirizine, have a similar effect on sICAM-1 released in nasal secretions during the pollen season. 相似文献
1000.
SG Grossi FB Skrepcinski T DeCaro DC Robertson AW Ho RG Dunford RJ Genco 《Canadian Metallurgical Quarterly》1997,68(8):713-719
Periodontal disease is a common infection-induced inflammatory disease among individuals suffering from diabetes mellitus. The purpose of this study was to assess the effects of treatment of periodontal disease on the level of metabolic control of diabetes. A total of 113 Native Americans (81 females and 32 males) suffering from periodontal disease and non-insulin dependent diabetes mellitus (NIDDM) were randomized into 5 treatment groups. Periodontal treatment included ultrasonic scaling and curettage combined with one of the following antimicrobial regimens: 1) topical water and systemic doxycycline, 100 mg for 2 weeks; 2) topical 0.12% chlorhexidine (CHX) and systemic doxycycline, 100 mg for 2 weeks; 3) topical povidone-iodine and systemic doxycycline, 100 mg for 2 weeks; 4) topical 0.12% CHX and placebo; and 5) topical water and placebo (control group). Assessments were performed prior to and at 3 and 6 months after treatment and included probing depth (PD), clinical attachment level (CAL), detection of Porphyromonas gingivalis in subgingival plaque and determination of serum glucose and glycated hemoglobin (HbA1c). After treatment all study groups showed clinical and microbial improvement. The doxycycline-treated groups showed the greatest reduction in probing depth and subgingival Porphyromonas gingivalis compared to the control group. In addition, all 3 groups receiving systemic doxycycline showed, at 3 months, significant reductions (P < or = 0.04) in mean HbA1c reaching nearly 10% from the pretreatment value. Effective treatment of periodontal infection and reduction of periodontal inflammation is associated with a reduction in level of glycated hemoglobin. Control of periodontal infections should thus be an important part of the overall management of diabetes mellitus patients. 相似文献