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61.
Three different lasers were compared under the same conditions for their effectiveness at producing photodynamic damage to normal colon following sensitization with aluminium sulphonated phthalocyanine (AlSPc). One laser was an argon ion pumped continuous wave (CW) dye laser and the other two were pulsed at 10 kHz (copper vapour laser pumped dye laser, and 5 Hz (flashlamp pumped dye laser). The CW and 10 kHz laser were equally effective at producing damage. The 5 Hz laser failed to produce a photodynamic effect, although occasionally caused a photomechanical effect when the laser fibre was placed touching the colonic mucosa. Quantitative analysis suggests that the high energy pulses of the flashlamp pumped dye laser saturate AlSPc, so very little of the available energy can be used to produce a photodynamic effect, in contrast to the two other lasers which do not produce saturation conditions.  相似文献   
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BACKGROUND: The long-term prognosis of diabetic patients with multivessel coronary artery disease (CAD) treated by surgical or percutaneous coronary revascularization is significantly worse as compared to non-diabetics. Lower rates of complete revascularization may be one factor that influences the poor long-term outcome in the diabetic population. Our study assessed the impact of complete revascularization on the long-term prognosis in diabetic patients with CAD treated by percutaneous coronary intervention (PCI). The study included 658 consecutive diabetic patients (mean age, 60.9+/-10.1 years) who underwent PCI. Multivessel disease was present in 352 patients (53.5%). Revascularization was complete in 94 (26.7%) and incomplete in 258 (73.3%) patients with multivessel disease. Reasons for incomplete revascularization included angioplasty of only the culprit lesion (43.4%); small vessel size (22.8%); moderate lesion, defined as diameter stenosis 50-69% (18.6%); chronic total occlusion of the non-intervened vessel (6.6%); and others (8.5%). Overall survival rate at 5 years was 87.4%. Patients who underwent complete revascularization had a 94.5% survival rate, compared to 83.0% for those with incomplete revascularization (p<0.001). Similarly, the rates of myocardial infarction-free survival were significantly higher in patients with complete versus incomplete revascularization (92.9% versus 79.9%, respectively). Incomplete revascularization was the most powerful independent predictor of mortality at follow-up (relative risk 95% confidence interval, 1.54-7.69; p=0.003). Our data suggest that complete myocardial revascularization may improve the long-term prognosis after PCI of diabetic patients with multivessel CAD.  相似文献   
63.
Infection with the human immunodeficiency virus type 1 (HIV-1) results in decreased cell-mediated immunity, which includes decreased delayed hypersensitivity to skin test antigens. HIV-1 seropositivity and skin test reactivity to purified protein derivative (PPD) were determined among 2042 healthy Haitian adults with normal chest radiographs. Among HIV-1-seropositive individuals, 52.3% (146/279) had PPD reactions greater than or equal to 10 mm compared with 67.2% (1184/1763) of the seronegative adults (P less than .001). However, the percentage of HIV-1-seropositive individuals with PPD reactions greater than or equal to 5 mm was similar to the percentage of seronegative adults with PPD reactions greater than or equal to 10 mm (180/279 [64.5%] vs. 1184/1763 [67.2%]). Assuming that the rate of prior infection with Mycobacterium tuberculosis was similar for HIV-1-seronegative and -seropositive populations, these data provide support for the recent recommendations to use induration of greater than or equal to 5 mm as evidence of past infection with M. tuberculosis in HIV-1 seropositive adults.  相似文献   
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INTRODUCTION: The effect of pelvic radiotherapy on anorectal function is not clearly documented and is investigated in this prospective study. METHODS: Thirty-one males (median age, 70 years) with carcinoma of the prostate (n = 28) and bladder (n = 3) completed proctitis/incontinence symptom score questionnaires and anorectal physiology studies before and six weeks after pelvic radiotherapy. At six months after completion of radiotherapy, 25 of these patients were studied again. The results were expressed as medians and ranges and compared by the Mann-Whitney U test (2-tailed). RESULTS: Six weeks and six months after treatment, respectively, the proctitis symptom scores (0 (0-4) vs. 2 (0-7) (P < 0.001) vs. 2 (0-5) (P < 0.001)) and the incontinence symptom scores (0 (0-5) vs. 4 (0-11) (P < 0.001) vs. 3 (0-14) (P < 0.001)) increased. Urgency, frequency of defecation, anorectal pain, incontinence to liquid stool and to flatus, and alteration in lifestyle were significant symptoms after treatment. The following measurements decreased: anal canal resting pressure (83 (35-137) vs. 79 (26-152) (P = NS) vs. 71 (29-97) (P < 0.01) cm H2O), the squeeze increment (152 (51-135) vs. 162 (63-321) (P = NS) vs. 108 (45-296) (P < 0.042) cm H2O), and the maximum tolerated rectal volume (245 (115-450) vs. 194 (112-344) (P < 0.05) vs. 200 (109-350) (P < 0.138) ml). The rectal electrosensory threshold increased (20 (5.4-44) vs. 22 (9-50.5) (P < 0.134) vs. 31.5 (13.6-76) (P < 0.001) mA). CONCLUSIONS: Anorectal symptoms at six weeks after pelvic radiotherapy are related to reduced rectal capacity and compounded at six months by diminished internal and external sphincter function and rectal mucosal sensitivity.  相似文献   
67.
Conventional radiographs are useful for visualising isthmic spondylolysis and play a key role in dynamic analysis. MRI evaluates degenerative changes in the adjacent discs and foraminal narrowing. CT scans are particularly suited to high-resolution depiction of osseous abnormalities.  相似文献   
68.
Interstitial pneumonitis is a well documented, rare complication of methotrexate (MTX). We describe a patient with rheumatoid arthritis (RA) taking MTX for more than 3 years who then developed severe interstitial pneumonitis after a third infliximab infusion. Other similar cases are reviewed. Infliximab may potentiate pulmonary toxicity of MTX.  相似文献   
69.
Background: Egyptian street youth use substances including tobacco, illicit drugs, and pharmaceutical drugs. To understand the circumstances, including adverse childhood experiences, that place adolescents at risk for engaging in substance use, we conducted in-depth interviews among a sample of Egyptian street children. Methods: From youth residing at or attending Caritas, a non-profit organization, which provides shelter and education to street youth, seven girls and twelve boys, aged 12–18 years, participated in open-ended, in-depth interviews. Results: Eight out of the 19 participants reported family history (early exposure) to substance use; and seven of them were initiated by either a family member (sibling), friend or coworker. Most of the participants reported a history of conflict with or abuse (verbal or physical) by their parents or siblings, or stressful situations at home; they used substance(s) to alleviate their stress. Few attended school, and some were forced to work and help their family. Conclusions: Among Egyptian youth, adverse childhood experiences, such as poverty, child abuse, and family substance use, challenge somewhat susceptible youths and lead them to the path of substance use and addiction. Prevention intervention should be multifaceted, culturally adaptable, and primarily targeting the social environment during childhood.  相似文献   
70.
Background Percutaneous coronary interventions (PCIs) in patients with multivessel coronary artery disease (CAD) may be staged or performed in a single session. No data exist about the relative safety and efficacy of these 2 strategies. Our aim was to compare short-term and long-term outcomes of patients with multivessel CAD who underwent PCI in 1 versus 2 sessions. Methods and Results The study included 264 consecutive patients who underwent treatment in our center during 1997 and 1998. PCI was conducted in a single session in 129 patients and was staged in 135 patients. The mean interval between the sessions in the staged group was 45.6 ± 22.3 days. The rates of major adverse cardiac events (MACEs) during in-hospital stay did not differ significantly between the staged (combined for both stages) and nonstaged groups (2.2% vs 4.6%; P = .28). A trend for lower event rates at 30-day (2.9% vs 6.9%; P = .13) and 1-year follow-up (26.1 vs 35.9; P = .08) favored the staged arm. Diameter stenosis ≥50% was found in 17% of patients in the staged group in the second session and was successfully retreated in most of them. No MACE occurred between the sessions. Multivariate analysis identified staging of the procedure as a single independent predictor of MACE at 1-year follow-up (P = .05). Conclusion Our results suggest that a practical staging strategy within 4 to 8 weeks is safe and allows for identification and treatment of potential excessive proliferative response in the previously intervened lesions during the second procedure. (Am Heart J 2002;143:1017-26.)  相似文献   
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