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11.
Marie-Paule Roth Hlne Coppin Patrick Descoins Jean-Bernard Ruidavets Anne Cambon-Thomsen Michel Clanet 《Journal of neuroimmunology》1991,34(2-3):215-222
The polymorphism at the HLA-DPB1 locus has been characterized in a large number of patients with multiple sclerosis (n = 112) and in healthy controls (n = 115). Both patients and controls lived in the southwest of France (in the Pyrénées Atlantiques) and had similar ethnic background. The typing procedure involved the selective amplification of the second exon of the DPB1 locus by polymerase chain reaction, followed by hybridization of the amplified DNA with 14 sequence-specific oligonucleotide probes. Individual alleles were identified by the pattern of hybridization of the different probes. The distribution of the DPB1 alleles was not significantly different in multiple sclerosis patients and controls (p = 0.11). This does not corroborate the reported association of multiple sclerosis with the primed lymphocyte typing (PLT)-defined DPw4 specificity and is not in favour of a role played by polymorphic residues of the DP molecule in susceptibility to multiple sclerosis. 相似文献
12.
M. Laurin Council Jennifer M. Gardner Cynthia Helms Ying Liu Lynn A. Cornelius Anne M. Bowcock 《Experimental dermatology》2009,18(5):485-487
Abstract: The risks of developing malignant melanoma (MM) include ultraviolet irradiation and genetic factors. To examine the contribution of rare and common variation within known MM genes in sporadic US MM patients, coding regions of known MM susceptibility genes [cyclin-dependent kinase inhibitor 2A ( CDKN2A ), cyclin-dependent kinase 4, melanocortin 1 receptor ( MC1R ) and tyrosinase ( TYR )] were resequenced in 109–135 MM cases. The significance of variants was examined by comparing their frequencies in 390 cancer-free controls. Potential deleterious mutations in CDKN2A were found in two patients and two others had variants of unknown significance. Cases were more likely than controls to harbour the MC1R 'R' variants known or predicted to alter its function ( P = 0.002), particularly the R160W variant ( P = 0.0035). The associated TYR R402Q variant (rs1126809*A) was found in 29% of cases, similar to what has been described previously. One MM patient with a family history of MM, who had developed other skin cancers, was homozygous for a novel TYR variant (P406L) of unknown significance. Hence, rare variants in TYR may be important risk factors for skin cancer. 相似文献
13.
Skoug John W. Borin Marie T. Fleishaker Joseph C. Cooper Anne M. 《Pharmaceutical research》1991,8(12):1482-1488
The mechanism of release from sustained-release adinazolam mesylate tablets was assessed by the Higuchi equation and by analysis of drug release profiles through 60% released using the Peppas equation. Computed values of the diffusional exponent, n, ranged from 0.59 to 0.66. Values of n in this range are consistent with a mixed mechanism of release, with diffusion of drug through the hydrated polymer matrix and relaxation of this matrix being the principal processes controlling release. The rate of in vitro drug release was increased for half tablets relative to whole tablets and is attributed to an increase in the surface to volume ratio of half tablets of about 16%. This increase in surface-to-volume ratio of half tablets was reflected by an increase in the constant, k, from the Peppas equation of 20–23% and by an increase in the slope of Higuchi plots of 12–18% for four lots of tablets. In vivo/in vitro relationships from two bioavailability studies were thoroughly evaluated. Using either a linear or a quadratic relationship, an in vivo/in vitro correlation exists for sustained-release adinazolam mesylate tablets. 相似文献
14.
15.
Najat C Daw Wayne L Furman Clinton F Stewart Lisa C Iacono Mark Krailo Mark L Bernstein Janet E Dancey Rose Anne Speights Susan M Blaney James M Croop Gregory H Reaman Peter C Adamson 《Journal of clinical oncology》2005,23(25):6172-6180
PURPOSE: Epidermal growth factor receptor is expressed in pediatric malignant solid tumors. We conducted a phase I trial of gefitinib, an epidermal growth factor receptor tyrosine kinase inhibitor, in children with refractory solid tumors. PATIENTS AND METHODS: Gefitinib (150, 300, 400, or 500 mg/m2) was administered orally to cohorts of three to six patients once daily continuously until disease progression or significant toxicity. Pharmacokinetic studies were performed during course one (day 1 through 28). RESULTS: Of the 25 enrolled patients, 19 (median age, 15 years) were fully evaluable for toxicity and received 54 courses. Dose-limiting toxicity was rash in two patients treated with 500 mg/m2 and elevated ALT and AST in one patient treated with 400 mg/m2. The maximum-tolerated dose was 400 mg/m2/d. The most frequent non-dose-limiting toxicities were grade 1 or 2 dry skin, anemia, diarrhea, nausea, and vomiting. One patient with Ewing's sarcoma had a partial response. Disease stabilized for 8 to > or = 60 weeks in two patients with Wilms' tumor and two with brainstem glioma (one exophytic). At 400 mg/m2, the median peak gefitinib plasma concentration was 2.2 microg/mL (range, 1.2 to 3.6 microg/mL) and occurred at a median of 2.3 hours (range, 2.0 to 8.3 hours) after drug administration. The median apparent clearance and median half-life were 14.8 L/h/m2 (range, 3.8 to 24.8 L/h/m2) and 11.7 hours (range, 5.6 to 22.8 hours), respectively. Gefitinib systemic exposures were comparable with those associated with antitumor activity in adults. CONCLUSION: Oral gefitinib is well tolerated in children. Development of the drug in combination with cytotoxic chemotherapy will be pursued. 相似文献
16.
Understanding the minimum clinically important difference: a review of concepts and methods. 总被引:2,自引:0,他引:2
Anne G Copay Brian R Subach Steven D Glassman David W Polly Thomas C Schuler 《The spine journal》2007,7(5):541-546
BACKGROUND CONTEXT: The effectiveness of spinal surgery as a treatment option is currently evaluated through the assessment of patient-reported outcomes (PROs). The minimum clinically important difference (MCID) represents the smallest improvement considered worthwhile by a patient. The concept of an MCID is offered as the new standard for determining effectiveness of a given treatment and describing patient satisfaction in reference to that treatment. PURPOSE: Our goal is to review the various definitions of MCID and the methods available to determine MCID. STUDY DESIGN: The primary means of determining the MCID for a specific treatment are divided into anchor-based and distribution-based methods. Each method is further subdivided and examined in detail. METHODS: The overall limitations of the MCID concept are first identified. The basic assumptions, statistical biases, and shortcomings of each method are examined in detail. RESULTS: Each method of determining the MCID has specific shortcomings. Three general limitations in the accurate determination of an MCID have been identified: the multiplicity of MCID determinations, the loss of the patient's perspective, and the relationship between pretreatment baseline and posttreatment change scores. CONCLUSIONS: An ideal means of determining the MCID for a given intervention is yet to be determined. It is possible to develop a useful method provided that the assumptions and methodology are initially declared. Our efforts toward the establishment of a MCID will rely on the establishment of specific external criteria based on the symptoms of the patient and treatment intervention being evaluated. 相似文献
17.
Acta Endoscopica - C’est un test de sélection. C’est un outil important de communication et d’information, c’est dire si elle doit être connue, comprise et bien... 相似文献
18.
Annie Mathieu Stéphanie Mazza Dominique Petit Anne Décary Jessica Massicotte-Marquez Jacques Malo Jacques Montplaisir 《Clinical neurophysiology》2007,118(7):1538-1544
OBJECTIVE: The aim of this study was to determine whether EEG slowing is more pronounced in older than younger OSAS patients and to verify whether this cortical slowing is correlated to daytime performance, respiratory perturbation and sleep fragmentation. METHODS: Twelve young OSAS patients (mean age 38.2+/-2.0 y) and 13 older OSAS patients (mean age 62.2+/-1.9 y) along with 13 young controls (mean age 35.8+/-2.0 y) and 14 older controls (mean age 60.2+/-2.0 y) underwent a polysomnographic evaluation followed by a waking EEG recording. As a global index of cortical slowing, a ratio of slow-to-fast frequencies was calculated in all cortical regions. Daytime performance was assessed using the four choice reaction time test. RESULTS: Differences in waking EEG and in daytime performance were analyzed by ANOVAs with Group and Age as factors. Waking EEG did not yield a Group by Age interaction. OSAS patients had higher ratios across all regions than controls. Similarly, daytime performance revealed no Group by Age interaction. However, OSAS patients showed more lapses than controls and older subjects were slower than younger subjects. CONCLUSIONS: Our results indicate that age does not interact with OSAS to worsen the severity of cortical slowing, but age can add to the OSAS effect to worsen daytime performance deficits in OSAS patients. SIGNIFICANCE: The daytime performance deficits observed particularly in elderly OSAS patients warrant a careful clinical assessment of these patients to prevent accidents and injuries. 相似文献
19.
Sylvia J T Jansen Wilma Otten Anne M Stiggelbout 《Journal of clinical oncology》2004,22(15):3181-3190
PURPOSE: Many studies have determined cancer patients' preferences for adjuvant therapy, for example, by asking patients the extent of benefit they would need in order to accept the therapy. However, little is known about the determinants that influence these preferences. Our research goal was to explore which determinants underlie patients' preferences by means of a literature review. METHODS: PubMed searches were conducted to identify studies in which cancer patients' preferences for adjuvant therapy had been elicited by means of a treatment preference instrument. Twenty-three papers were evaluated with regard to reported relationships between preferences and potential determinants. A total of 40 determinants were recorded and classified into one of seven categories: (1) treatment-related determinants, (2) sociodemographic characteristics and current quality of life, (3) clinical characteristics, (4) measurement instrument-related determinants, (5) time-related determinants, (6) cognitive/affective determinants, and (7) specialist-related determinants. Results: The benefit and toxicity of treatment, experience of the treatment, and having dependents (eg, children) living at home were important determinants of patients' preferences. Furthermore, qualitative data suggested that cognitive/affective and specialist-related determinants might have a large impact on patients' treatment preferences. CONCLUSION: Our results show that patients' preferences cannot fully be explained on the basis of treatment-related determinants and patient and clinical characteristics. More research is needed in the area of cognitive/affective and specialist-related determinants because of the lack of quantitative results. Furthermore, we recommend carrying out larger studies in which the (internal) relationships between determinants and preferences are assessed in the context of a cognitive cost-benefit model. 相似文献
20.
Anne?Helene?Garde ?se?Marie?Hansen Johnni?Hansen 《International archives of occupational and environmental health》2009,82(10):1219-1228