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991.
BACKGROUND: Lasers and light sources are now used worldwide for permanent or prolonged hair removal. Patients now prefer lasers and light sources for hair removal because of their noninvasiveness and fewer reported side effects. OBJECTIVE: To study and report on leukotrichia that developed following application of intense pulsed light (IPL). METHODS: From February 9, 2001 to February 14, 2002 a total of 821 patients were treated for unwanted hair. The system used was a noncoherent IPL system, with a 650 nm flashlamp filter; the parameters used varied with different Fitzpatrick skin types. The patients were treated monthly, with the rate of hair loss, measured by hair counts, and possible side effects recorded. RESULTS: Twenty-nine of 821 patients treated developed leukotrichia. Thirteen patients had no white or gray hairs before IPL therapy; the remaining 16 patients, who had few white hairs before treatment reported accelerated development of new white hairs starting after the first or second IPL therapy. Restoration of hair color occurred in 9 patients and the remaining 20 patients had no improvement or worsening of the condition within the next 2-6 months. CONCLUSION: Temporary or permanent leukotrichia may develop following IPL and laser hair removal therapy. This finding may be explained by the difference in the thermal relaxation times of melanocytes and germinative cells. The light absorbed and the heat produced by melanin may be sufficient enough to destroy or impair the function of melanocytes but insufficient to damage the hair follicle cells.  相似文献   
992.
INTRODUCTION: Accessory pathways (AP) exhibiting Mahaim physiology are amenable to radiofrequency (RF) catheter ablation. The recording of an AP potential is an excellent guide for selection of ablation site. The purpose of this study is to determine whether the pathway potential is always a fast potential. METHODS: Ten patients (six females, mean age, 30 +/- 12 years) with preexcited tachycardias involving a Mahaim pathway underwent electrophysiological study and subsequent attempts at RF ablation. Mahaim potentials (M-potential) recorded at the site of successful ablation were reviewed and classified by at least two reviewers. RESULTS: In all patients, Mahaim pathways were characterized as atriofascicular types. The M-potential was fast in seven patients (group one), and slow in the remaining patients (group two). All group two patients had a history of prior failed ablation. Atrial electrograms were recorded closer to the QRS onset in group one. Atrium to fast M-potential (42 +/- 15 ms) was shorter than atrium to slow M-potential (83 +/- 12 ms, P = 0.03) but M-potentials were recorded with similar distance before local ventricular electrogram (P = NS). Ablation was successful in all patients with mean of 2.9 +/- 1.4 RF applications per patient. Ablation data were similar between the two groups (P = NS). No complications occurred. During 12 months of follow-up, no recurrence was observed. CONCLUSION: Our results illustrated that the activation potential of Mahaim pathways is not always a fast potential. One-third of Mahaim pathways can be mapped and ablated when the slow type of M-potential was used as a target for ablation. We also confirmed high efficacy of catheter ablation of Mahaim pathways guided by activation potentials.  相似文献   
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Blepharochalasis--a case report   总被引:1,自引:0,他引:1  
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995.
In order to determine the clinical and laboratory features of X-linked agammaglobulinemia, the records of 33 male patients with XLA were reviewed during 22 years (1980-2002) in the Iranian referral center of primary immunodeficiency disorders. The patients' ages ranged from 20 to 360 months (median 113 months). The median age at the onset of the disease was 8 months and the median age of diagnosis was 48 months, with a median diagnosis delay of 33 months. Almost all of the patients presented common infectious diseases, which were: pneumonia, otitis, diarrhea, sinusitis, and arthritis. During the course of illness, infections in the respiratory tract, gastrointestinal tract, central nervous system, and musculoskeletal system were seen in 93.9%, 75.8%, 33.3%, and 21.2% of XLA patients, respectively. The most common complications of these patients were chronic infections in 75.8% of them, including: chronic otitis media, chronic sinusitis, chronic diarrhea, and bronchiectasis.  相似文献   
996.
An increasing rate of addiction is being witnessed nowadays as a social issue that affects families as the most fundamental social institution and leads to divorce. Therefore, the aim of the present study was to investigate addiction pathology and demonstrate a paradigmatic model of addiction in the families on the verge of breakdown. To do so, in a qualitative design and based on the content analysis approach, 18 families that had been referred to family courts were selected through purposive sampling method and were studied through semi-structured interviews. In addition, some interviews were conducted with judges and attorneys to confirm and complete the data. The data analysis was conducted according to the conventional content method and the results were presented in a paradigmatic model, including context, causes, strategy and consequences. The results of the present study emphasize the importance of recognizing factors associated with addiction pathology in a paradigmatic model by which more comprehensive programs can be designed for harm reduction and addiction prevention.  相似文献   
997.
Purpose Renal ischemia/reperfusion (I/R) injury is a common clinical problem associated with significant mortality and morbidity. One newly described strategy to reduce this damage is remote perconditioning (RPEC), in which short-time ischemia of a limb during renal ischemia reduces the I/R-induced kidney injury. This study aimed to assess whether RPEC confer protection through changes in pro-inflammatory mediators. Methods Rats were subjected to right nephrectomy and randomized into: sham (no intervention), I/R (subjected to 45-min left renal ischemia) and RPEC group (subjected to four cycles of 5-min I/R of the femoral artery administered during renal ischemia). After 24-h, blood, urine, and kidney samples were collected. Biochemical indicators of renal dysfunction were measured in the cases of Neutrophil gelatinase-associated lipocalin (NGAL), and N-acetyl-B-diglucosaminidase (NAG) activity. Inflammatory cytokines [interleukin (IL)-6 and tumor necrosis factor-alpha, TNF-α] expression in the renal tissues as well as Periodic acid-Schiff stained histological sections were evaluated. Results I/R resulted in renal dysfunction, as evidenced by higher renal NGAL expression and urinary NAG activities. This was accompanied by increased TNF-α and IL-6 expressions as well as histological changes in this group. However, RPEC improved renal histology and function compared with the I/R group. Furthermore, the RPEC group showed decreases in TNF-α and IL-6 expression. Conclusions These results suggest that RPEC reduces the dysfunction and injury associated with I/R of the kidney. This technique reduced the pro-inflammatory cytokine in the kidney. RPEC could be a promising strategy against I/R-induced acute kidney injury partly by down-regulation of inflammatory mediators.  相似文献   
998.
Objective: 18α-Glycyrrhetinic acid (18α-GA), a bioactive component of Glycyrrhiza glabra, has been shown in vitro immunomodulatory effects on dendritic cells (DCs). The aim of the present study is to evaluate the in vivo effect of 18α-GA on DCs and T cell responses.

Methods: 18α-GA was intraperitoneally administered to mice and splenic DCs were evaluated for expression of co-stimulatory molecules using flow cytometry. Isolated DCs were added to mixed lymphocyte reaction (MLR) and the proliferation of T cells was measured using BrdU assay. The level of IFN-γ in the MLR supernatant was determined by enzyme-linked immunosorbent assay. The in vivo effect of isolated DCs on antigen-specific delayed type hypersensitivity (DTH) response, and the number of regulatory T (Treg) cells in mice spleen by flow cytometry, were investigated.

Results: DCs isolated from 18α-GA-treated mice expressed lower levels of CD40 (p < 0.05) and MHC II (p < 0.01) compared to those of control group. In MLR assay isolated DCs decreased T cell proliferation to 83.54% ± 4.3% of control (p < 0.05). The level of IFN-γ in the MLR supernatant was declined to 25.2% ± 6.8% of control. In DTH test, DCs isolated from 18α-GA-treated mice significantly suppressed antigen-specific cell mediated immune response (3.3 ± 1 mm in test group versus 6.5 ± 1.2 mm in control group, ρ < 0.01). The percentage of Treg cells in spleen of 18α-GA-treated mice (6.37% ± 2.3%) was lower than that of control group (13.85% ± 0.4%, ρ < 0.05).

Conclusions: In vivo administration of 18α-GA resulted in inhibition of DCs maturation and T cell-mediated responses, the effects that may candidate this compound for its possible benefits in immune-mediated diseases.  相似文献   

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