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71.
STEVEN Q. WANG MD JEFF T. COUNTERS MPH MARY E. FLOR RN BRIAN D. ZELICKSON MD 《Dermatologic surgery》2006,32(2):249-255
BACKGROUND: The 1,450 nm laser has been effective in treating acne. Microdermabrasion may help treat acne and reduce skin barriers to increase the delivery rate of topical anesthetics. OBJECTIVES: To evaluate the efficacy, safety, and pain associated with the treatment of inflammatory facial acne with the 1,450 nm laser alone versus microdermabrasion plus the 1,450 nm laser. METHODS: Twenty patients with facial acne were treated with the 1,450 nm laser alone and microdermabrasion plus the 1,450 nm laser in a randomized, split-face trial. RESULTS: Laser alone and microdermabrasion plus laser significantly reduced the total number of acne lesions. Mean reductions of 53.5% and 55.6% were found after three treatments for laser alone and microdermabrasion plus laser, respectively. Clinical improvement was maintained 12 weeks after the last treatment. Mean pain scores were 5.3 6 1.5 for microdermabrasion plus laser and 5.2 6 1.5 for laser alone. There was no statistical difference between treatment levels for efficacy or pain. There was an average 10% increase in sequential pain as the laser treatment progressed. CONCLUSION: The 1,450 nm laser is effective, well tolerated, and safe for treating facial acne. This small pilot study did not demonstrate increased clinical efficacy or decreased associated pain with the addition of microdermabrasion to treatment with the 1,450 nm laser. A larger study may be needed to demonstrate any additional benefit. 相似文献
72.
Comparative Short-Term Effects of Methyl Tertiary Butyl Ether and Unleaded Gasoline Vapor in Female B6C3F1 Mice 总被引:4,自引:3,他引:1
MOSER GLENDA J.; WONG BRIAN A.; WOLF DOUGLAS C.; MOSS OWEN R.; GOLDSWORTHY THOMAS L. 《Toxicological sciences》1996,31(2):173-183
PS-6 unleaded gasoline (UG) and methyl tert-butyl ether (MTBE),an UG additive, with long-term exposure at high concentrationsincreased liver tumors selectively in female mice. PS-6 UG isa liver tumor promoter in N-nitrosodiethylamine-initiated femalemice and produces short-term effects potentially relevant toits tumor promoting ability. The new formulation of UG (91-01)and MTBE were evaluated for similar short-term effects in mouseliver. Mice were exposed to 7814 ppm MTBE, 2014 ppm 91-01 UG,or 2028 ppm PS-6 UG vapor for 3 or 21 days, 6 hr/day, 5 days/week.Relative liver weights increased and uterine weights decreasedin MTBE-, 91-01 UG-, and PS-6 UG-exposed mice. Because the decreasein relative uterine weight is suggestive of hormonal modulation,we evaluated the effects of MTBE, 91- 01 UG, and PS-6 UG invivo on hepatic 17-ß estradiol metabolism in vitro.Gavage treatment with either blend of UG and with MTBE increasedestrogen metabolism in isolated mouse hepatocytes. Hepatic microsomalP450 activity was assessed by 7-pentoxyresorufin-O-dealkylase(PROD) and 7-ethoxyresorufin-O-deethylase (EROD) activities.Similar increases in P450 content and PROD and EROD activitieswere observed in all exposed mice as compared to controls. Nohepatoxicity was observed in any treatment group. The hepaticlabeling index, as measured by the incorporation of 5-bromo-2'-deoxyuridine,was increased in all exposed mice at 3 days but not 21 days,indicating that MTBE and 91-01 UG are also hepatic mitogens.These data demonstrate that a newer blend of UG and the UG additiveMTBE elicit short-term effects similar to those of PS-6 UG.Given that these effects are potentially related to tumor promotionand the general lack of genotoxic activity, MTBE and 91-01 UGmay exhibit tumor promoting activity similar to that seen withPS-6 UG. Since the liver is under multihormonal control, theincrease in hepatic estrogen metabolism and uterine effectssupport a potential role for endocrine modulations in both MTBE-and UG-induced hepatocarcinogenesis. 相似文献
73.
74.
NICHOLAS JOHNSON Lecturer VALERIE A. JOHNSON Research Fellow JOHN FISHER Lecturer BRIAN JOBBINGS Senior Design Engineer JEFFREY BANNISTER Medical Physicist RICHARD J. LILFORD Professor of Gynaecology 《BJOG : an international journal of obstetrics and gynaecology》1991,98(1):36-41
Summary. Continuous fetal monitoring was achieved with a fetal scalp pulse oximetry sensor in 86 labours. The average recorded fetal oxygen saturation in early labour (cervical dilatation < 5 cm) was 68% (SD 13%). At the end of labour (cervical dilatation ≥ 9 cm) the recorded mean oxygen saturation was 58% (SD 17%). The largest range of readings during a single labour was 81%-11% but this drop was associated with cord compression. The average SD during 1 h of normal labour was 10%. A second group of 40 fetuses was monitored during induction of labour before and after elective amniotomy. Oxygen saturation did not appear to change after amniotomy (mean change −0.4%, SD 1.2%) and there was no difference between mean antenatal or early intrapartum readings. We excluded the amniochorionic membranes as a possible source of data corruption by measuring their in vitro absorption spectra and confirming that they do not preferentially absorb light of either 660 or 940 nm wavelength. Non-invasive pulse oximetry can be used to monitor the fetus before and during labour. 相似文献
75.
GARTH R. MCDONALD KENNETH J. GRAHAM BRIAN G. BARRATT-BOYES 《ANZ journal of surgery》1982,52(6):573-575
Two atypical patients with spontaneous aortocaval llstulae with a successful outcome, are presented. Lack of physician awareness is considered an important contributor to diagnostic delay. A finding at cardiac catheterization is described. Review of the Engligh literature shows that satisfactory results in the management of this condition can now be expected. 相似文献
76.
The vasopressin precursor in the rat hypothalamus has been studied, using trypsin to release desglycinamide vasopressin and coupling it to glycinamide (T&G treatment). The resulting amidated nonapeptide was detected and measured with a radioimmunoassay for vasopressin. The ?vasopressin” produced in this way had the full immunoreactivity of the authentic peptide but eluted from an hplc column 1 min earlier and appeared to have a larger molecular weight. It was found that T&G treatment generated vasopressin immunoreactivity in extracts of the supraoptic nucleus (SON) of the Brattleboro rat in just the same way as it did in normal animals. Furthermore, this procedure produced vasopressin immunoreactivity in those hplc fractions from Brattleboro SON extracts that corresponded with the elution time of vasopressin precursor. Similar amounts of ?vasopressin” could be generated from Brattleboro and normal SONs. These results support the suggestion that the Brattleboro SON synthesises an aberrant vasopressin precursor which is not processed by the cell. 相似文献
77.
BERNARD L. CROWE DAVID HAILEY GEOFFREY T. BENNESS IAN A. BURGESS JAMES ROCHE WILLIAM A. SORBY SUZANNE Le P. LANGLOIS DAVID J. DEWHURST DAVID R. HUNT BRIAN M. TRESS MAKHAN S. KHANGURE IAN G. McDONALD KENNETH J. SIDDLE MARK D. BENSON 《Journal of Medical Imaging and Radiation Oncology》1990,34(3):219-222
Audited cost data from two public hospital installations participating in a trial of the utilisation and efficacy of magnetic resonance imaging are presented. The data cover the period July 1987 to June 1988 when both installations had attained stable patterns of operation. One hospital operated a superconductive system and the other a resistive magnetic resonance imaging unit. Depreciation and salaries represented the major components of cost. 相似文献
78.
B. B. J. MAJEWSKI E. L. RHODES BRIAN WATSON 《Clinical and experimental dermatology》1981,6(6):583-590
Neutrophil mobility was investigated in thirteen cases of granuloma annulare and in twelve cases of necrobiosis lipoidica and found to be normal. Plasma from these patients did not inhibit the random or directed migration of neutrophils obtained from normal donors. The nature of the ‘in vivo’ defect of neutrophil migration previously reported in these conditions is at present unclear. 相似文献
79.
JEAN BOUSQUET FATMÉ DJOUKADAR BRIAN HEWITT BERNARD GUERIN FRANÇOIS-BERNARD MICHEL 《Clinical and experimental allergy》1985,15(1):29-35
Pollen extracts are stable in solutions containing 50% glycerol. The stability of Dermatophagoides pteronyssinus (Dp) extracts have not been determined. Two lyophilised extracts (Dp and cocksfoot pollen) were reconstituted in 50% glycerol and stored for up to 6 months at +4°C. Every day the extracts were placed at room temperature for 1 hr to mimic the natural use of allergen extracts by allergists. Every 2 months the extracts initially prepared were compared to freshly reconstituted extracts by means of prick skin tests in fifteen allergic patients. It was observed that cocksfoot pollen extract is stable but there appears a slight but significant (P > 0.05) decay in activity when the extract stored for up to 6 months was compared with a freshly prepared extract. On the other hand there is a significant (P > 0.01) decay in activity of the Dp extract after 2 months of storage. Dermatophagoides pteronyssinus and cocksfoot pollen extracts behave differently when stored. These findings have particular importance in the diagnosis and treatment of allergic disorders. 相似文献
80.
ANN F. DINGLE BRIAN BINGHAM RAMANI KRISHNAN JOHN G. GIBB CAROLE J. THOMPSON LIAM M. FLOOD 《Clinical otolaryngology》1993,18(5):415-418
Non-attendance by patients for elective surgery with insufficient time to find replacement leads to wasted theatre time and wasted resources. The introduction of pre-admission clinics at the North Riding Infirmary, Middlesbrough has alleviated this problem and has led to considerable financial savings. A 12 month prospective study has shown an increase in operations performed from 3738 to 3944. Financial savings have not been taken into consideration in this publication. 相似文献