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71.
PURPOSE: To compare the preclinical and clinical pharmacokinetic properties of paclitaxel formulated as a Cremophor-free, albumin-bound nanoparticle (ABI-007) and formulated in Cremophor-ethanol (Taxol). EXPERIMENTAL DESIGN: ABI-007 and Taxol were given i.v. to Harlan Sprague-Dawley male rats to determine pharmacokinetic and drug disposition. Paclitaxel pharmacokinetic properties also were assessed in 27 patients with advanced solid tumors who were randomly assigned to treatment with ABI-007 (260 mg/m(2), 30 minutes; n = 14) or Taxol (175 mg/m(2), 3 hours; n = 13), with cycles repeated every 3 weeks. RESULTS: The volume of distribution at steady state and clearance for paclitaxel formulated as Cremophor-free nanoparticle ABI-007 were significantly greater than those for paclitaxel formulated with Cremophor (Taxol) in rats. Fecal excretion was the main elimination pathway with both formulations. Consistent with the preclinical data, paclitaxel clearance and volume of distribution were significantly higher for ABI-007 than for Taxol in humans [21.13 versus 14.76 L/h/m(2) (P = 0.048) and 663.8 versus 433.4 L/m(2) (P = 0.040), respectively]. CONCLUSIONS: Paclitaxel formulated as ABI-007 differs from paclitaxel formulated as Taxol, with a higher plasma clearance and a larger volume of distribution. This finding is consistent with the absence of paclitaxel-sequestering Cremophor micelles after administration of ABI-007. This unique property of ABI-007 could be important for its therapeutic effectiveness.  相似文献   
72.
PURPOSE: The epidermal growth factor receptor (EGFR) and cyclin D1 are overexpressed in lung carcinogenesis. The rexinoid, bexarotene, represses cyclin D1 and EGFR expression in vitro. It was hypothesized that combining bexarotene with the EGFR inhibitor, erlotinib, would augment clinical activity. PATIENTS AND METHODS: In vitro studies and a phase I clinical trial were performed. Twenty-four patients with advanced aerodigestive tract cancers were enrolled; 79% had non-small-cell lung cancer (NSCLC). The primary objective was to determine the maximum-tolerated dose. Clinical activity was a secondary objective. RESULTS: Combining erlotinib with bexarotene enhanced growth suppression in vitro compared with each single-agent treatment. This cooperatively repressed cyclin D1 expression. Clinically, the most frequent toxicities were mild hypertriglyceridemia and skin rash. Two serious treatment-related adverse events occurred (creatine phosphokinase elevation attributed to antilipid therapy and a case of generalized pain). Five objective responses (four partial and one minor) were observed in NSCLC patients. Responses were observed in males and smokers. EGFR sequence analyses did not reveal activating mutations in tumors from assessable responding patients. Median time to progression was 2.0 months; overall survival time was 14.1 months; and 1-year survival rate was 73.8%. CONCLUSION: The recommended phase II doses are erlotinib 150 mg/d and bexarotene 400 mg/m2/d orally. These agents can be administered in combination at the recommended single-agent doses without added toxicity. Overall survival and clinical features of responding patients differ from prior reports of single-agent erlotinib treatment. These findings are encouraging and warrant further investigation of this regimen.  相似文献   
73.
This study examined attitudes to human papillomavirus (HPV) testing among a purposively selected sample of women from four ethnic groups: white British, African Caribbean, Pakistani and Indian. The design was qualitative, using focus group discussion to elicit women's attitudes towards HPV testing in the context of cervical cancer prevention. The findings indicate that although some women welcomed the possible introduction of HPV testing, they were not fully aware of the sexually transmitted nature of cervical cancer and expressed anxiety, confusion and stigma about HPV as a sexually transmitted infection. The term 'wart virus', often used by medical professionals to describe high-risk HPV to women, appeared to exacerbate stigma and confusion. Testing positive for HPV raised concerns about women's sexual relationships in terms of trust, fidelity, blame and protection, particularly for women in long-term monogamous relationships. Participation in HPV testing also had the potential to communicate messages of distrust, infidelity and promiscuity to women's partners, family and community. Concern about the current lack of available information about HPV was clearly expressed and public education about HPV was seen as necessary for the whole community, not only women. The management of HPV within cervical screening raises important questions about informed participation. Our findings suggest that HPV testing has the potential to cause psychosocial harm to women and their partners and families.  相似文献   
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Pituitary tumor apoplexy (PTA) classically comprises sudden-onset headache, loss of vision, ophthalmoparesis, and decreased consciousness. It typically results from hemorrhage and/or infarction within a pituitary adenoma. Presentation is heterologous, and optimal management is debated. The time course of recovery of cranial nerve deficits (CNDs) and headaches is not well established. In this study, a retrospective series of consecutive patients with PTA managed at a single academic institution over a 22-year period is presented. Headaches at the time of surgery were more severe in the early and subacute surgical cohort and improved significantly within 72 h postoperatively (p < 0.01). At one year, 90% of CNDs affecting cranial nerves (CNs) 3, 4, and 6 had recovered, with no differences between early (<4 d), subacute (4–14 d), and delayed (>14 d) time-to-surgery cohorts. Remarkably, half recovered within three days. In total, 56% of CN2 deficits recovered, with the early surgery cohort including more severe deficits and recovering at a lower rate (p = 0.01). No correlation of time-to-surgery and rapidity of recovery of CNDs was observed (p = 0.65, 0.72). Surgery for PTA is associated with rapid recovery of CNDs in the early, subacute, and delayed time frames, and with rapid headache improvement in the early and subacute time frames in 50% or more of patients.  相似文献   
76.
Purpose:To describe the clinical features and treatment outcomes in spontaneous uveal effusion syndrome (UES).Methods:A 10-year retrospective chart review of UES patients from a tertiary eye center was carried out. Optical coherence tomography (OCT), fundus fluorescein angiography, and ultrasound biomicroscopy (UBM) scans were performed. UES was managed based on presenting best-corrected visual acuity (BCVA), symptoms, and fundus findings. Patients with secondary causes of uveal effusion were excluded.Results:Twenty-five eyes of 16 patients were included. Of the 16 patients, 14 (88%) were male and 9 (56%) had bilateral disease. Fifteen of 25 affected eyes had nanophthalmos (axial length (AL) <20.5 mm) and 6 had hyperopia with AL >20.5 mm. The presenting mean distance BCVA was 0.74 ± 0.64 logMAR (mean Snellen: 20/100). Eleven eyes had exudative retinal detachment, and 4 also had exudative choroidal detachment (CD). Choroidal thickness (CT) was increased in 11 eyes on B-scan ultrasonography, and the mean CT was 1.74 ± 0.38 mm. Sub-retinal fluid (SRF) and retinal folds were the most common OCT findings. UBM findings included shallow angles, peripheral CD, and supra-ciliary effusion. A combination of local and systemic corticosteroids was used to successfully treat 12 eyes, 6 needed surgery, and 7 were observed. Partial sclerectomy with anterior chamber maintainer-assisted SRF drainage was the favored surgery. The median period of follow-up was 6.5 months (0.1–76 months), and the mean distance BCVA at the last follow-up was 0.58 ± 0.42 logMAR (mean Snellen: 20/80).Conclusion:UES can be suitably managed both medically and surgically based on clinical presentation.  相似文献   
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78.
The incidence of testicular cancer, cryptorchidism and defective spermatogenesis is increasing probably due to environmental and lifestyle-related factors. The aim of this review is to briefly describe and comment on the principal lifestyle factors. The recent findings that the electromagnetic waves following the use of the cell phone and the prolonged exposure to the noise stress cause relevant testicular dysfunction in man or animals reinforce the hypothesis of the importance of lifestyle-related factors.  相似文献   
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80.
Capecitabine has been more recognized for its cardiotoxicity with an incidence that varies widely. It demonstrates its toxicity in the forms of acute coronary syndrome, arrhythmias and, to a lesser extent, cardiomyopathy. There are several proposed theories including coronary vasospasm, endothelial injury, and oxidative stress. We present a case of capecitabine-induced cardiomyopathy in a patient with pancreatic cancer and mild coronary artery disease, and shed light on other cardio-toxic agents, their proposed mechanism of cardiotoxicity, and on cardiomyopathy in general.  相似文献   
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