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21.
Purpose To develop a calorimetry-based model for estimating the time-dependence of molecular mobility during the isothermal relaxation of amorphous organic compounds below their glass transition temperature (T g).Methods The time-dependent enthalpy relaxation times of amorphous sorbitol, indomethacin, trehalose and sucrose were estimated based on the nonlinear Adam‐Gibbs equation. Fragility was determined from the scanning rate dependence of T g. Time evolution of the fictive temperature was determined from T g, the heat capacity of the amorphous and crystalline forms, and from the enthalpy relaxation data.Results Relaxation time changes significantly upon annealing for all compounds studied. The magnitude of the increase in relaxation time does not depend on any one parameter but on four parameters: T g, fragility, and the crystal–liquid and glass–liquid heat capacity differences. The obtained mobility data for indomethacin and sucrose, both stored at T g−16 K, correlated much better with their different crystallization tendencies than did the Kohlrausch‐Williams‐Watts (KWW) equation.Conclusions The observed changes in relaxation time help explain and address the limitations of the KWW approach. Due consideration of the time-dependence of molecular mobility upon storage is a key element for improving the understanding necessary for stabilizing amorphous formulations.  相似文献   
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背景:阿德福韦双酯(ADV) 是一种有效治疗野生型和耐拉米夫定乙肝病毒(HBV)的核苷酸类药物。在使用核苷酸类药物治疗慢性乙肝时,当治疗时间为 48、96、144周时,耐ADV变异体出现的累积发生率分别为0、 0.8-3%和0-5.9%。目的:研究67例对拉米夫定耐药且接受ADV治疗的慢性乙肝患者耐ADV病毒变异体的表型和基因型特点。方法:HBV DNA含量采用实时定量PCR技术。ADV变异体检测采用基质辅助激光解吸电离/飞行时间质谱为基础的基因分型  相似文献   
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The immunoglobulin G subclass responses to cytomegalovirus (CMV) after red cell (RBC) transfusion were studied in 26 seropositive surgery patients and 34 transfused seropositive oncology patients. Also included as controls were 18 surgical patients who received no RBCs during surgery. None of the 78 patients studied had IgG2 to CMV before or after transfusion. The absence of a total IgG response to CMV after transfusion could not be attributed to preexisting deficiencies in one or more subclasses, because all 78 patients had similar levels of IgG1, IgG3, and IgG4 to CMV before transfusion. Discriminant analysis was used for statistical evaluation of the combined CMV subclass responses in each patient and the individual subclass responses. Individual patients responded to CMV antigens with an increase in concentration in any of the three subclasses or any combination of the subclasses, excluding IgG2. IgG subclass analysis showed that 10 of 27 patients who did not respond with at least a fourfold total IgG titer rise had a significant increase in IgG subclass antibodies to CMV. Three of 33 patients with at least a fourfold total IgG titer rise lacked a subclass response. These results suggest that the measurement of IgG subclasses may be a sensitive indicator of immune response to CMV.  相似文献   
25.
In the community, acute hypoglycaemia is commonly caused by therapies for diabetes mellitus or the excessive consumption of alcohol. Although most episodes do not require admission to hospital, little information is available on the causes and outcome of those that do. We retrospectively surveyed adult patients admitted to a large urban teaching hospital with acute hypoglycaemia in a 12-month period, identifying 56 admissions of 51 patients. Forty-one had diabetes mellitus, 33 (80%) of whom were receiving treatment with insulin. The others had hypoglycaemia induced by excessive consumption of alcohol or by deliberate self-poisoning with insulin. A history of psychiatric illness and/or chronic alcoholism was common. Neurological manifestations of hypoglycaemia were the principal reason for admission, observed on 50 occasions (89%), and 11 events (20%) had precipitated convulsions. Although many patients (59%) had received treatment for hypoglycaemia before admission, hypoglycaemia recurred in 16% of patients in hospital. Four patients (7%) died following admission, but in only one case was this the direct result of hypoglycaemia. However, within 15 months of the index hypoglycaemia event, a further six patients (11%) had died, mostly of causes unrelated to hypoglycaemia. Patients who require hospital admission for treatment of hypoglycaemia have a high incidence of neurological manifestations, a high rate of mental illness and other medical disorders, and may represent a high-risk subgroup with a poor long-term prognosis.   相似文献   
26.

Background  

Many adjuvant trials have been undertaken in an attempt to reduce the risk of recurrence among patients who undergo surgical resection for locally advanced renal cancer. However, no clear benefit has been identified to date. This systematic review was conducted to examine the exact role of adjuvant therapy in renal cancer setting.  相似文献   
27.
BackgroundLong-term efficacy and tolerability data are not yet available for patch formulations of dopamine agonists in restless legs syndrome.MethodsEfficacy and safety of rotigotine (0.5–4 mg/24 h), formulated as a once-daily transdermal system (patch), were investigated in an open extension (SP710) of a preceding 6-week placebo-controlled trial (SP709, 341 randomized patients) in patients with idiopathic restless legs syndrome. For efficacy assessment the international RLS severity scale (IRLS), the RLS-6 scales, the clinical global impressions (CGI) and the QoL-RLS questionnaire were administered. In addition, long-term tolerability and safety were assessed.ResultsOf 310 patients who finished the controlled trial, 295 (mean age 58 ± 10 years, 66% females) with a mean IRLS score of 27.8 ± 5.9 at baseline of SP709 were included. We report results after one year of this ongoing long-term trial. Two hundred twenty patients (retention rate = 74.6%) completed the 12-month follow-up period. The mean daily dose was 2.8 ± 1.2 mg/24 h with 4 mg/24 h (40.6%) being the most frequently applied dose; 14.8% were sufficiently treated with 0.5 or 1.0 mg/24 h. The IRLS total score improved by −17.4 ± 9.9 points between baseline and end of Year 1 (p < 0.001). The other measures of severity, sleep satisfaction and quality of life supported the efficacy of rotigotine (p < 0.001 for pre-post-comparisons of all efficacy variables). The tolerability was described as “good” or “very good” by 80.3% of all patients. The most common adverse events were application site reactions (40.0%), which led to withdrawal in 13.2%. Further relatively frequent adverse events were nausea (9.5%) and fatigue (6.4%). Two drug-related serious adverse events, nausea and syncope, required hospitalization. Symptoms of augmentation were not reported by the patients.ConclusionRotigotine provided a stable, clinically relevant improvement in all efficacy measures throughout one year of maintenance therapy. The transdermal patch was safe and generally well tolerated by the majority of patients. Comparable to any transdermal therapy, application site reactions were the main treatment complication.  相似文献   
28.
BACKGROUND: Continuous administration of a dopamine agonist could be used to treat patients with restless legs syndrome. Our aim was to investigate the efficacy of transdermal rotigotine in the treatment of idiopathic restless legs syndrome. METHODS: In this randomised, double-blind, placebo-controlled trial, 458 patients with moderate-to-severe idiopathic restless legs syndrome (average baseline International Restless Legs Syndrome Study Group severity rating scale [IRLS] sum score of 28.1) were randomly assigned to receive transdermal rotigotine 1 mg over 24 h (n=115), 2 mg over 24 h (n=112), or 3 mg over 24 h (n=114), or to receive placebo (n=117). Study medication was delivered via patches, applied once a day for 6 months. Randomisation was done with a computer-generated randomisation list, stratified by centre. Primary efficacy outcomes were absolute change from baseline to end of maintenance in IRLS sum score and in the clinical global impressions (CGI) item 1 score, assessed by analysis of covariance in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, number NCT00136045. FINDINGS: Efficacy analyses were done on 112 patients in the 1 mg group, 109 in the 2 mg group, 112 in the 3 mg group, and 114 in the placebo group. Mean change in IRLS sum score from baseline at the end of the maintenance phase was -13.7 (SE 0.9) in the 1 mg group, -16.2 (0.9) in the 2 mg group, -16.8 (0.9) in the 3 mg group, and -8.6 (0.9) in the placebo group (p<0.0001 for treatment difference vs placebo with each dose). Mean change in CGI item 1 score from baseline at the end of the maintenance phase was -2.09 (0.14) in the 1 mg group, -2.41 (0.14) in the 2 mg group, -2.55 (0.14) in the 3 mg group, and -1.34 (0.14) in the placebo group (p<0.0001 for treatment difference vs placebo with each dose). Skin reactions, mostly mild or moderate, were seen in 145 (43%) of 341 patients who received rotigotine and in two (2%) of 117 who received placebo. Ten patients had serious adverse event that were deemed to be related to rotigotine: elevation of liver enzymes (one patient), worsening of tinnitus (one patient), non-response to anticoagulation (one patient), electrocardiogram changes (one patient), and application-site reactions (six patients). No admissions to hospital were needed for the application-site reactions, and they all resolved within a short time of patch removal without any other therapeutic intervention. The rate of typical dopaminergic side-effects in patients who received rotigotine was low; no signs of augmentation were noted. INTERPRETATION: 24 h transdermal delivery of low-dose rotigotine could be used to relieve the night-time and daytime symptoms of restless legs syndrome. FUNDING: Schwarz Biosciences.  相似文献   
29.
Background Perceived age is important to women and is a primary driver for topical product use and facial cosmetic surgery. Changes in facial features and biophysical skin parameters with chronological age and their associations with perceived age have not been described in Asian populations. Objective To investigate the relationship between biophysical properties of the skin, visual features of skin ageing and perceived facial age in Chinese women. Methods Facial photographs were collected of 250 Chinese women, aged 25–70 years in Shanghai, China. The perceived facial age was determined and related to the chronological age for each participant and to a range of visual assessments of skin appearance and objective biophysical measurements of the skin. The profile of changes in these parameters with age was investigated together with the differences in those parameters for women judged to look younger than their chronological age and those judged to look older than their chronological age. Results Large discrepancies in perceived age (up to 29 years) were found in women of the same chronological age. Each objective skin measure and visual assessment parameter had a stronger correlation with perceived age than with chronological age. The strongest relationships to perceived age were for wrinkles and hyperpigmentation. Skin colour, hydration and trans‐epidermal water loss (TEWL) had weaker associations with perceived age. Women judged to look older than their chronological age had significantly higher scores than those judged to look younger for coarse wrinkles and hyperpigmentation across all age groups. The appearance differences between these groups were evident in composite facial images of the same average chronological age. Conclusions We have identified the skin attributes which differ with perceived age in Chinese women. Perceived age is a better measure of the biological age of facial skin than is chronological age in this population.  相似文献   
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