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1.
顺铂聚乳酸微球的药物释放特性及肝动脉栓塞研究 总被引:5,自引:0,他引:5
对顺铂聚乳酸微球进行了体外药物释放和家犬肝动脉栓塞研究。该微球粒径范围为50~200μm,平均粒径为115.76±35.94μm,顺铂含量为37.16%(W/W);体外药物释放机制符合Higuchi方程;肝动脉栓塞后8h,肝组织顺铂浓度高达21.55±12.18μg/g,明显高于肝动脉灌注顺铂组:3.16±0.09μg/g(P<0.05);肝动脉栓塞组的顺铂血浓峰值、各取血点浓度及曲线下面积AUC皆低于肝动脉灌注顺铂组。可望达到提高栓塞部位的药物疗效,降低全身毒副反应的作用。 相似文献
2.
PC Chamyal A Mehta SL Ojha JR Bhardwaj 《Indian journal of otolaryngology and head and neck surgery》1991,43(1):26-27
Primary tuberculous pathology in nasolpolypi is a rare condition. A case of bilateral ethmoidal polypi with tubercular lesion diagnosed on histopathologlcal examination is being reported and the available relevant literature has been reviewed. 相似文献
3.
A number of vitamin D3 metabolites inhibit benzodiazepine- and dimethyl sulfoxide-induced differentiation of Friend erythroleukemia cells. The inhibition is dose dependent and occurs at nM concentrations. The order of potency of these compounds is 1,25-dihydroxycholecalciferol greater than 1,25,26-trihydroxycholecalciferol greater than 1,24R,25-trihydroxycholecalciferol greater than 1 alpha-hydroxycholecalciferol greater than 24R,25-dihydroxycholecalciferol greater than 25S,26-dihydroxycholecalciferol. The inhibition is maximal when the vitamin D3 analogs are added together with the inducer, and becomes progressively decreased with delayed addition. These results suggest that the vitamin D3 metabolites may play a regulatory role in erythropoiesis. 相似文献
4.
Human and animal studies have implicated dopamine in appetite regulation, and family studies have shown that BMI has a strong genetic component. Dopamine availability is controlled largely by three enzymes: COMT, MAOA and MAOB, and by the dopamine transporter SLC6A3, and each gene has a well-characterized functional variant. Here we look at these four functional polymorphisms together, to investigate how heritable variation in dopamine levels influences the risk of obesity in a cohort of 1150, including 240 defined as obese (BMI ≥ 30). The COMT and SLC6A3 polymorphisms showed no association with either weight, BMI or obesity risk. We found, however, that both MAOA and MAOB show an excess of the low-activity genotypes in obese individuals ( MAOA: χ2 = 15.45, p = 0.004; MAOB: χ2 = 8.05, p = 0.018). Additionally, the MAOA genotype was significantly associated with both weight (p = 0.0005) and BMI (p = 0.001). When considered together, the 'at risk genotype' - low activity genotypes at both the MAOA and MAOB loci - shows a relative risk for obesity of 5.01. These results have not been replicated and, given the experience of complex trait genetics, warrant caution in interpretation. In implicating both the MAOA and MOAB variants, however, this study provides the first indication that dopamine availability (as opposed to other effects of MAOA) is involved in human obesity. It is therefore a priority to assess the associations in replication datasets. 相似文献
5.
6.
Usha Chinappen-Horsley Glen M Blake Ignac Fogelman Tim D Spector 《BMC musculoskeletal disorders》2007,8(1):113
Background
Skeletal ratios and bone lengths are widely used in anthropology and forensic pathology and hip axis length is a useful predictor of fracture. The aim of this study was to show that skeletal ratios, such as length of femur to height, could be accurately measured from a DXA (dual energy X-ray absorptiometry) image. 相似文献7.
BACKGROUND: Antileukotriene agents have been shown to be beneficial in chronic asthma. Although patients with cough variant asthma have cough with minimal wheezing and dyspnea, airway hyperresponsiveness from chronic inflammation is believed to be the underlying mechanism. OBJECTIVE: To evaluate the effectiveness of montelukast, a leukotriene receptor antagonist, in the treatment of cough variant asthma. METHODS: Fourteen patients with cough variant asthma participated in a randomized, double-blind, placebo-controlled trial with a 7- to 10-day baseline period and a 4-week treatment period with montelukast, 10 mg, or placebo daily. Inclusion criteria were (1) chronic cough with a duration of at least 4 weeks with minimal or no wheezing or dyspnea and (2) forced expiratory volume in 1 second of 50% to 85% of predicted and reversibility of 12% with use of an inhaled beta-agonist or forced expiratory volume in 1 second greater than 85% and positive methacholine challenge results. Patients fulfilled the minimum criteria for cough frequency and symptom scores for randomization. RESULTS: Eight patients received montelukast and 6 received placebo. The primary efficacy variable, mean percentage change from baseline in cough frequency, was significantly improved by the second week, and by the fourth week the mean percentage change from baseline was 75.7% for the treatment group and 20.7% for the placebo group. CONCLUSIONS: The leukotriene receptor antagonist montelukast seems to be effective in the treatment of cough variant asthma. Larger studies are recommended to confirm this effect. 相似文献
8.
Dawn Hastreiter MD PhD ; Jeannie Chao BS ; QI Wang MD ; Richard M. Ozuna MD ; Myron Spector PhD 《Wound repair and regeneration》2004,12(4):430-438
That a contractile actin isoform has been found in cells of other cartilage tissues in healing and disease states prompted this investigation of the presence of alpha-smooth muscle actin (alpha-SMA) in pathological human intervertebral disc tissue. The presence of this isoform has been reported in human intervertebral disc specimens obtained at autopsy from subjects for whom there were no reported symptoms. An objective of this study was to evaluate the cell density and percentage of alpha-SMA-containing cells in pathological nucleus pulposus tissue obtained from lumbar disc surgery from 17 patients. Additionally, explants of nucleus pulposus material were cultured to determine how alpha-SMA expression changed with time in vitro. Seventy-six 5-mm diameter explants (approximately 2 mm thick) pooled from six lumbar surgeries were cultured for 1, 2, 4, or 6 weeks. Microtomed sections of paraffin-embedded specimens were stained with hematoxylin and eosin or a monoclonal antibody to alpha-SMA. Histologically, cells were categorized as to alpha-SMA phenotype (positive or negative), and the areal cell density was determined. The evaluation of the cultured nucleus pulposus explants also included documentation of the percentage of cells that were round or elongated and the percentage of the cells that were part of a group (group: >/= 2 cells). Every nucleus pulposus section exhibited the presence of alpha-SMA-containing cells, which accounted for approximately 24 percent of the cells in vivo. In vivo, the cell density was significantly higher in older individuals (p = 0.02). The average time for cell outgrowth from the explants was 8.6 days. Approximately 10-15 percent of the cells in the explants stained positive for alpha-SMA. The time in culture had no significant effect on any of the outcome measures except the percentage of alpha-SMA-containing cells that were round (p = 0.008), with values decreasing through 4 weeks and then slightly rising at 6 weeks. The role of alpha-SMA in intervertebral disc pathology warrants further investigation. 相似文献
9.
Incidence and prevalence of the sexual dysfunctions: A critical review of the empirical literature 总被引:11,自引:0,他引:11
The research which has assessed the incidence and prevalence of sexual dysfunctions is reviewed. Twenty-three studies are evaluated. Studies completed with community samples indicate a current prevalence of 5–10% for inhibited female orgasm, 4–9% for male erectile disorder, 4–10% for inhibited male orgasm, and 36–38% for premature ejaculation. Stable community estimates with regard to the current prevalence of female sexual arousal disorder, vaginismus, and dyspareunia are not available. Recent studies completed with clinical samples suggest an increase in the frequency of orgasmic and erectile dysfunction and a decrease in premature ejaculation as presenting problems. Desire disorders have increased as presenting problems in sex clinics, with recent data indicating that males outnumber females. Methodological limitations of these studies are identified and suggestions for future research are offered. 相似文献
10.
BACKGROUND: Many patients with asthma or chronic obstructive pulmonary diseaseuse their medication inhalers incorrectly. General practitioners,pharmacists and other health care providers do not always havethe opportunity to instruct patients in correct inhaler technique. OBJECTIVE: To find out whether the inhaler technique and respiratory symptomsof patients can be improved after instruction by practice assistants. METHODS: Single blind, randomized intervention study in which 48 patientswho had been using a dry powder inhaler for at least one monthtook part. Their inhaler technique was videotaped on two visitswith a two-week interval between visits. The inhaler techniqueon the videos was subsequently scored by two experts on ninecriteria. At both visits the patients completed a questionnaireabout their respiratory symptoms. After the first video, 25patients were randomly chosen to receive instruction from oneof six practice assistants who had followed a one evening courseabout inhaler instruction, and who had been issued an instruction-set. RESULTS: The patients who received instruction had a significantly greaterreduction in number of mistakes at the second visit than thepatients who did not (P = 0.01). The instructed patients alsoreported less dyspnoea at the second visit (P = 0.03). No effectof instruction was found on wheezing, cough and sputum production. CONCLUSION: The inhaler technique of patients can be improved significantlyby the instruction of patients by trained practice assistants,possibly resulting in less dyspnoea. Keywords. Administration-inhalation, obstructive lung diseases, airways symptoms, patient-education, general practice. 相似文献