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51.
Bellew Supriya G. MD Lee Catherine BS † Weiss Margaret A. MD ‡ Weiss Robert A. MD ‡ 《Dermatologic surgery》2005,31(S3):1218-1222
Background. Facial acne scarring has been treated with multiple methods with varying degrees of improvement. Although the 1,320 nm neodymium:yttrium-aluminum-garnet (Nd:YAG) laser has been widely used to improve photoaging, studies analyzing its effects on atrophic acne scarring are limited.
Objective. To evaluate the efficacy of a dynamic cryogen-cooled 1,320 nm Nd:YAG laser for the treatment of atrophic facial acne scars in a larger cohort of patients with long-term follow-up.
Methods. Twenty-nine patients (skin phototypes I–IV) with facial acne scarring received a mean of 5.5 (range 2–17) treatments with a 1,320 nm Nd:YAG laser. Objective physician assessment scores of improvement were determined by side-by-side comparison of preoperative and postoperative photographs at a range of 1 to 27 months (mean 10.4 months) postoperatively. Subjective patient self-assessment scores of improvement were also obtained.
Results. Acne scarring was significantly improved by both physician and patient assessment scores. Mean improvement was 2.8 ( p < .05 ) on a 0- to 4-point scale by physician assessment and 5.4 ( p < .05 ) on a 0- to 10-point scale by patient assessment. No significant complications were observed.
Conclusions. Nonablative laser skin resurfacing with a 1,320 nm Nd:YAG laser can effectively improve the appearance of facial acne scars with minimal adverse sequelae. 相似文献
Objective. To evaluate the efficacy of a dynamic cryogen-cooled 1,320 nm Nd:YAG laser for the treatment of atrophic facial acne scars in a larger cohort of patients with long-term follow-up.
Methods. Twenty-nine patients (skin phototypes I–IV) with facial acne scarring received a mean of 5.5 (range 2–17) treatments with a 1,320 nm Nd:YAG laser. Objective physician assessment scores of improvement were determined by side-by-side comparison of preoperative and postoperative photographs at a range of 1 to 27 months (mean 10.4 months) postoperatively. Subjective patient self-assessment scores of improvement were also obtained.
Results. Acne scarring was significantly improved by both physician and patient assessment scores. Mean improvement was 2.8 ( p < .05 ) on a 0- to 4-point scale by physician assessment and 5.4 ( p < .05 ) on a 0- to 10-point scale by patient assessment. No significant complications were observed.
Conclusions. Nonablative laser skin resurfacing with a 1,320 nm Nd:YAG laser can effectively improve the appearance of facial acne scars with minimal adverse sequelae. 相似文献
52.
Margaret J Bowers Nick J Orr Si Dempsey H Denis Alexander 《Blood coagulation & fibrinolysis》2006,17(5):409-411
We present a case of Bernard Soulier syndrome in a 9-year-old boy caused by a novel genetic mutation. This child was shown to be homozygous for a single nucleotide deletion (c.1077delG) in the GP1BA gene not previously reported. Clinically, the boy has become refractory to platelet transfusions with both allo-antibodies and iso-antibodies and a massive transfusion requirement for ongoing haemorrhage. We describe the critical role that the blood product transfusion continues to play in the management of Bernard Soulier syndrome and discuss therapeutic options in these patients. 相似文献
53.
Phospho-akt expression is associated with a favorable outcome in non-small cell lung cancer. 总被引:3,自引:0,他引:3
Amit Shah William A Swain Donna Richardson John Edwards Duncan J Stewart Catherine M Richardson Daniel E B Swinson Dipika Patel J Louise Jones Kenneth J O'Byrne 《Clinical cancer research》2005,11(8):2930-2936
Akt, a Serine/Threonine protein kinase, mediates growth factor-associated cell survival. Constitutive activation of Akt (phosphorylated Akt, P-Akt) has been observed in several human cancers, including lung cancer and may be associated with poor prognosis and chemotherapy and radiotherapy resistance. The clinical relevance of P-Akt in non-small cell lung cancer (NSCLC) is not well described. In the present study, we examined 82 surgically resected snap-frozen and paraffin-embedded stage I to IIIA NSCLC samples for P-Akt and Akt by Western blotting and for P-Akt by immunohistochemistry. P-Akt protein levels above the median, measured using reproducible semiquantitative band densitometry, correlated with a favorable outcome (P = 0.007). Multivariate analysis identified P-Akt as a significant independent favorable prognostic factor (P = 0.004). Although associated with a favorable prognosis, high P-Akt levels correlated with high tumor grade (P = 0.02). Adenocarcinomas were associated with low P-Akt levels (P = 0.039). Akt was not associated with either outcome or clinicopathologic variables.Cytoplasmic (CP-Akt) and nuclear (NP-Akt) P-Akt tumor cell staining was detected in 96% and 42% of cases, respectively. Both CP-Akt and NP-Akt correlated with well-differentiated tumors (P = 0.008 and 0.017, respectively). NP-Akt also correlated with nodal metastases (P = 0.022) and squamous histology (P = 0.037).These results suggest P-Akt expression is a favorable prognostic factor in NSCLC. Immunolocalization of P-Akt, however, may be relevant as NP-Akt was associated with nodal metastases, a known poor prognostic feature in this disease. P-Akt may be a potential novel therapeutic target for the management of NSCLC. 相似文献
54.
ABSTRACT: Background: Most women will sustain some degree of trauma to the genital tract after vaginal birth. This study aimed to examine the association between maternal position at birth and perineal outcome in women who had a midwife‐attended, spontaneous vaginal birth and an uncomplicated pregnancy at term. Methods: Data from 3,756 births in a major public tertiary teaching hospital were eligible for analysis. The need for sutures in perineal trauma was evaluated and compared for each major factor studied (maternal age, first vaginal delivery, induction of labor, not occipitoanterior, use of regional anesthesia, deflexed head and newborn birthweight >3,500 g). Birth positions were compared against each other. Subgroup analysis determined whether birth positions mattered more or less in each of the major factors studied. The chi‐square test was used to compare categorical variables. Results: Most women (65.9%) gave birth in the semi‐recumbent position. Of the 1,679 women (44.5%) who required perineal suturing, semi‐recumbent position was associated with the need for perineal sutures, whereas all‐fours was associated with reduced need for sutures; these associations were more marked in first vaginal births and newborn birth weight over 3,500 g. When regional anesthesia was used, semi‐recumbent position was associated with a need for suturing, and lateral position associated with a reduced need for suturing. The four major factors significantly related to perineal trauma included first vaginal birth, use of regional anesthesia, deflexed head, and newborn weight more than 3,500 g. Conclusions: Women should be given the choice to give birth in whatever position they find comfortable. Maternity practitioners have a responsibility to inform women of the likelihood of perineal trauma in the preferred birth position. Ongoing audit of all clinicians attending births is encouraged to further determine effects of maternal birth position and perineal trauma, to investigate women's perception of comfortable positioning at birth, and to measure changes to midwifery practice resulting from this study. 相似文献
55.
56.
Genotype determining low catechol-O-methyltransferase activity as a risk factor for obsessive-compulsive disorder 下载免费PDF全文
Maria Karayiorgou Margaret Altemus Brandi L. Galke David Goldman Dennis L. Murphy Jurg Ott Joseph A. Gogos 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(9):4572-4575
In the present study, we address the role of the gene for catechol-O-methyltransferase (COMT), a key modulator of dopaminergic and noradrenergic neurotransmission, in the genetic predisposition to obsessive-compulsive disorder (OCD). We show that a common functional allele of this gene, which results in a 3- to 4-fold reduction in enzyme activity, is significantly associated in a recessive manner with susceptibility to OCD, particularly in males. This association is further supported by psychiatric evaluation of patients who carry microdeletions encompassing the comt gene. The mechanism underlying this sex-selective association remains to be defined and may include a sexual dimorphism in COMT activity, although close linkage with a nearby disease susceptibility locus cannot be excluded at this point. 相似文献
57.
58.
S. A. Baxendale W. van Paesschen P. J. Thompson A. Connelly J. S. Duncan W. F. Harkness S. D. Shorvon 《Epilepsia》1998,39(2):158-166
Summary: Purpose: Quantitative MRI techniques provide an unparalleled opportunity to examine in vivo the relationship between the extent and laterality of hippocampal pathology and associated neuropsychological deficits. The purpose of this study was to examine the nature of the relationship between quantitative measures of hippocampal pathology and neuropsychological measures, using a multivariate approach. Methods: We examined the relationship between two MRI measures of hippocampal structure; hippocampal volumes (HCvol) and T2 relaxation times (HCT2), and memory performance, in 80 presurgical temporal lobe epilepsy patients. Results: As a group, patients with left hippocampal sclerosis (LHS) performed more poorly that those with right hippocampal sclerosis (RHS) on immediate and delayed prose recall. In the group as a whole, right hippocampal volume was significantly correlated with the delayed recall of a complex figure. None of the verbal memory test scores were significantly correlated with the right or left HCvol or HCT2 measures. However, stepwise multiple regression analyses indicated that up to a third of the variation in specific test scores could be explained by the quantitative MRI hippocampal measures in conjunction with chronological age, and age at onset of habitual epilepsy. Left hippocampal measures explained 24% of the variance in the story-recall tasks, while right hippocampal measures explained 18% of the variance in a design-learning task and 32% of the variance in a figure-recall task. Conclusions: Our results provide some support for the lateralised model of material specific memory deficits, but suggest that a number of demographic and epilepsy-related factors may interact with the extent and laterality of hippocampal pathology in shaping the nature of the associated neuropsychological deficit. 相似文献
59.
Physical status score and trends in anesthetic complications 总被引:4,自引:0,他引:4
Since deaths due to anesthesia have now become rare, emphasis in quality assurance of anesthetic care must focus on morbidity rather than only on mortality. To facilitate comparisons of outcomes, data from a large anesthesia follow-up program (N = 112,000 anesthetics) were used to evaluate the usefulness of the American Society of Anesthesiologists' Physical Status score (PS) as an independent predictor of nonfatal adverse anesthetic complications. For each patient, the anesthesiologist filled out a form containing information about the patient, the anesthetic, the operative procedure, and outcomes in the operating and recovery rooms. Postoperative complications were assessed by a designated anesthesia follow-up nurse. We calculated the PS-specific complication rate by dividing the number of complications to patients in each PS category by the number of anesthetics given to patients in the same category. We found that PS-specific complication rates increased with increasing PS scores for most complications sought. For intraoperative and recovery room complications, the PS-specific rates increased from 1978-80 and 1981-83 as compared to 1975-77. However, there was no increase over time in the rate of postoperative major complications. After adjusting for patient, anesthesia, and surgery-related variables by multiple logistic regression, the relative odds of having an intraoperative or postoperative major complication were increased for patients classified PS2, PS3 and PS4 & 5 as compared to PS1. However, those in higher PS categories were less likely to have a recovery room complication than PS1 patients.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
60.
Duncan W. Blake Roger G. Evans John Ludbrook Oscar U. Petring 《Clinical and experimental pharmacology & physiology》1994,21(5):383-396
1. Eight conscious rabbits were repeatedly subjected to progressive reduction in central blood volume by gradually inflating a thoracic inferior vena caval-cuff so cardiac index (CI) fell at a constant 8.5% of baseline/min. 2. Caval-cuff inflations were performed after 10 min exposure to 100, 21, 12–14 and 8–10% O2, with and without the addition of 3–4% CO2, in randomized order. 3. The haemodynamic response to progressive reduction in central blood volume was biphasic. In Phase I, systemic vascular conductance index (SVCI) fell linearly, supporting mean arterial pressure (MAP). When CI had fallen to a critical level, Phase II occurred in which SVCI rose abruptly, MAP plummeted and respiratory drive progressively increased. 4. During Phase I, there were independent linear relationships between Pao2 (but not Pao2) and the rates at which SVCI and MAP changed during the progressive fall of CI. The higher the level of Pao2, the greater was the rate of fall of SVCI and the less the rate of fall of MAP. 5. There was an inverted U-shaped effect of Pao2, on the level of CI at which Phase II occurred: (a) during hyperoxia (100% O2), Phase II occurred later than during normoxia (21% O2); and (b) across the normoxic and hypoxic gas mixtures (21–8% O2, with and without added CO2), there was an independent linear relationship between Pao2 (but not Pao2 or Pao2×Pao2) and the level of CI at which Phase II occurred. That is, the lower the level of Pao2, the later was the onset of Phase II. This interaction is best explained by an increased level of central sympathetic vasoconstrictor drive during hypoxia. 相似文献