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1.
Photodynamic therapy (PDT) is based on the selective light activation of an exogenously given drug to patients. PDT acts mainly on cell membranes either of neovascular endothelial cells or of cancer cells leading to cancer cell death. Six drugs are now marketed based on clinical assays in various indications, which showed a clear cost efficiency as compared to other classical procedures. PDT is easy to handle and can be performed in medical installations fitting the conditions of health care in developing countries. Its cost effectiveness could represent an appropriate solution to the increasing number of cancers of various origin. However despite all the clinical results now available, PDT development remains slow. The reasons for this situation include cost of development, intellectual property, and competition between pharmaceutical companies.  相似文献   
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Surgery alone has long been the standard treatment for patients with operable non-small-cell lung cancer (NSCLC). However, despite complete resection, 5-year survival rates have been disappointing, with about 50% of patients eventually suffering relapse and death from disease. Randomized trials conducted in the 1980s hinted at a survival benefit for postoperative cisplatin-based regimens, but they were underpowered. A meta-analysis published in 1995 found a nonsignificant 13% reduction in the risk of death associated with cisplatin-based chemotherapy, with an increase of survival of 5% at 5 years. This led to renewed interest in adjuvant chemotherapy in resected NSCLC. Thousands of patients have been included in a new generation of randomized trials in the last 10 years. Most of these recent studies have now been reported and several have demonstrated a clear survival advantage for patients treated with platin-based adjuvant therapy. These results also suggest a greater benefit with modern two-drug regimens. In view of the most recent data, postoperative platin-based chemotherapy can now be considered the standard of care for completely resected NSCLC patients with good performance status.  相似文献   
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Proteases that reduce insulin-like growth factor binding protein-3 affinity for insulin-like growth factor-I have been found in various biological fluids from human beings and rats. The aim of this study was to assess the local and systemic role of insulin-like growth factor binding protein-3 proteases in the course of wound healing. Six rats had polyvinyl alcohol sponges implanted subcutaneously. Wound fluid and serum were collected 3 days after wounding. Gel filtration experiments showed that insulin-like growth factor-I was present as a 150 kDa complex in both serum and wound fluid. However, insulin-like growth factor binding protein-3 measured by Western ligand blotting was virtually absent in wound fluid. Co-incubation of serum and wound fluid resulted in an ethylenediamine tetraacetic acid-inhibitable degradation of serum insulin-like growth factor binding protein-3, suggesting the presence of an insulin-like growth factor binding protein-3 degrading activity in wound fluid. Incubation of ((125)I)-labeled insulin-like growth factor binding protein-3 in wound fluid and serum showed a rapid and time-dependent proteolysis of insulin-like growth factor binding protein-3 in wound fluid with metabolites similar to those generated by human term pregnant serum. No sign of insulin-like growth factor binding protein-3 degrading activity was observed in rat-serum. In conclusion, there is an insulin-like growth factor binding protein-3 proteolytic activity in wound fluid, and it is hypothesized that this activity results in a localized increase in insulin-like growth factor-I bioactivity.  相似文献   
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Whether peak bone mass is low among children with fractures remains uncertain. In a cohort of 125 girls followed over 8.5 years, 42 subjects reported 58 fractures. Among those, BMC gain at multiple sites and vertebral bone size at pubertal maturity were significantly decreased. Hence, childhood fractures may be markers of low peak bone mass acquisition and persistent skeletal fragility. INTRODUCTION: Fractures in childhood may result from a deficit in bone mass accrual during rapid longitudinal growth. Whether low bone mass persists beyond this period however remains unknown. MATERIALS AND METHODS: BMC at the spine, radius, hip, and femur diaphysis was prospectively measured over 8.5 years in 125 girls using DXA. Differences in bone mass and size between girls with and without fractures were analyzed using nonparametric tests. The contribution of genetic factors was evaluated by mother-daughter correlations and that of calcium intake by Cox proportional hazard models. RESULTS: Fifty-eight fractures occurred in 42 among 125 girls (cumulative incidence, 46.4%), one-half of all fractures affecting the forearm and wrist. Girls with and without fractures had similar age, height, weight. and calcium intake at all time-points. Before and during early puberty, BMC and width of the radius diaphysis was lower in the fracture compared with no-fracture group (p < 0.05), whereas aBMD and BMAD were similar in the two groups. At pubertal maturity (Tanner's stage 5, mean age +/- SD, 16.4 +/- 0.5 years), BMC at the ultradistal radius (UD Rad.), femur trochanter, and lumbar spine (LS), and LS projected bone area were all significantly lower in girls with fractures. Throughout puberty, BMC gain at these sites was also decreased in the fracture group (LS, -8.0%, p = 0.015; UD Rad., -12.0%, p = 0.004; trochanter, -8.4%, p = 0.05 versus no fractures). BMC was highly correlated between prepuberty and pubertal maturity (R = 0.54-0.81) and between mature daughters and their mothers (R = 0.32-0.46). Calcium intake was not related to fracture risk. CONCLUSIONS: Girls with fractures have decreased bone mass gain in the axial and appendicular skeleton and reduced vertebral bone size when reaching pubertal maturity. Taken together with the evidence of tracking and heritability for BMC, these observations indicate that childhood fractures may be markers for low peak bone mass and persistent bone fragility.  相似文献   
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Our aim was to develop and validate a new method to assess objectively and quantitatively the morphology of the nostrils after nasal or nasolabial surgery. We used digital analysis using specific mathematical algorithms to assess several geometric measurements, particularly of facial asymmetry, expressed in adimensional units. Forty-five patients with no facial anomalies (control group) were used initially to evaluate the method and to obtain variables for statistical reference. Thirty-five patients operated on for unilateral cleft lip and palate (cleft group) were then analysed and compared with the control group. Individual scores were obtained for each patient, computed, and correlated with those established by a lay panel. Statistical analysis showed good sensitivity and reliability (R>0.8).  相似文献   
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OBJECTIVE: Non-steroidal anti-inflammatory drugs (NSAIDs) are routinely used after coronary artery bypass surgery (CABG), yet their effects have seldom been evaluated in randomized controlled settings. The aim of this study was to examine the efficacy and safety of a commonly used NSAID, naproxen. We hypothesized that naproxen would reduce postoperative pain following CABG without increasing complications. METHODS: Patients (N=98) undergoing primary CABG were randomized to receive naproxen (500 mg q12hX5 doses via suppository started 1h after operation, followed by oral 250 mg q8hX6 doses) or placebo. Standard analgesic and anti-emetic regimens were available to both patient groups. Interventions were double-blinded. Primary end-points were postoperative pain measured before and after chest physiotherapy by visual analog scale and pulmonary slow vital capacity (SVC). RESULTS: Baseline characteristics were equivalent between the two groups. Over the first 4 postoperative days, naproxen decreased pain by 47+/-17% on average before chest physiotherapy (P=0.034), and 44+/-13% after chest physiotherapy (P=0.0092). Patients who received naproxen also had better preservation of SVC over the first 4 postoperative days (mean loss of SVC from baseline: 2.1+/-0.1 vs. 2.5+/-0.1l, naproxen vs. placebo, P=0.0032). This was concomitant with a lower white blood cell count observed in naproxen patients (9.2+/-0.3 vs. 12.7+/-1.5x10(9)/l, naproxen vs. placebo, P=0.03). Patients who received naproxen had more chest tube drainage after 4h postoperatively, but there was no difference in the incidence or amount of transfusions. There was no difference in medication use, length of stay, or in the incidence of atrial fibrillation, azotemia, and other complications. CONCLUSIONS: Naproxen is an effective and low-cost adjunct for optimization of pain control and lung recovery after CABG. Its use may result in increased chest tube drainage, but no apparent increase in other complications.  相似文献   
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