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991.
二十世纪初 ,广为普及的现代药物只有一个 :乙酰水杨酸 (阿司匹林 )。二十世纪四十年代 ,人类发现第一种抗菌素、第一种批量生产的抗疟药和第一种抗痨药。五、六十年代 ,很快研制出口服避孕药 ,治疗糖尿病的药 ,及治疗精神疾病、各种感染疾病、心血管疾病和癌症的药物。到七十年代 ,几乎每大类疾病都能找到有效药物 ,尽管这些药物的效果不很理想。但全球约有一半的人口似乎依然生活在十九世纪。他们由于贫穷 ,得不到、买不起现代药物 ;因用法不当而不能正确发挥药物疗效。1 975年 ,世界卫生大会提出“基本药物”和“国家药品政策”的概念 ,…  相似文献   
992.

Purpose

We sought to analyse clinical and oncological outcomes of patients after guided resection of periacetabular tumours and endoprosthetic reconstruction of the remaining defect.

Methods

From 1988 to 2008, we treated 56 consecutive patients (mean age 52.5 years, 41.1 % women). Patients were followed up either until death or February 2011 (mean follow up 5.5 years, range 0.1–22.5, standard deviation ± 5.3). Kaplan–Meier analysis was used to estimate survival rates.

Results

Disease-specific survival was 59.9 % at five years and 49.7 % at ten and 20 years, respectively. Wide resection margins were achieved in 38 patients, whereas 11 patients underwent marginal and seven intralesional resection. Survival was significantly better in patients with wide or marginal resection than in patients with intralesional resection (p = 0.022). Survival for patients with secondary tumours was significantly worse than for patients with primary tumours (p = 0.003). In 29 patients (51.8 %), at least one reoperation was necessary, resulting in a revision-free survival of 50.5 % at five years, 41.1 % at ten years and 30.6 % at 20 years. Implant survival was 77.0 % at five years, 68.6 % at ten years and 51.8 % at 20 years. A total of 35 patients (62.5 %) experienced one or more complications after surgery. Ten of 56 patients (17.9 %) experienced local recurrence after a mean of 8.9 months. The mean postoperative Musculoskeletal Tumor Society (MSTS) score was 18.1 (60.1 %).

Conclusion

The surgical approach assessed in this study simplifies the process of tumour resection and prosthesis implantation and leads to acceptable clinical and oncological outcomes.  相似文献   
993.

Background

Prostate-specific antigen (PSA) testing has limited accuracy for the early detection of prostate cancer (PCa).

Objective

To assess the value added by percentage of free to total PSA (%fPSA), prostate cancer antigen 3 (PCA3), and a kallikrein panel (4k-panel) to the European Randomised Study of Screening for Prostate Cancer (ERSPC) multivariable prediction models: risk calculator (RC) 4, including transrectal ultrasound, and RC 4 plus digital rectal examination (4+DRE) for prescreened men.

Design, setting, and participants

Participants were invited for rescreening between October 2007 and February 2009 within the Dutch part of the ERSPC study. Biopsies were taken in men with a PSA level ≥3.0 ng/ml or a PCA3 score ≥10. Additional analyses of the 4k-panel were done on serum samples.

Outcome measurements and statistical analysis

Outcome was defined as PCa detectable by sextant biopsy. Receiver operating characteristic curve and decision curve analyses were performed to compare the predictive capabilities of %fPSA, PCA3, 4k-panel, the ERSPC RCs, and their combinations in logistic regression models.

Results and limitations

PCa was detected in 119 of 708 men. The %fPSA did not perform better univariately or added to the RCs compared with the RCs alone. In 202 men with an elevated PSA, the 4k-panel discriminated better than PCA3 when modelled univariately (area under the curve [AUC]: 0.78 vs 0.62; p = 0.01). The multivariable models with PCA3 or the 4k-panel were equivalent (AUC: 0.80 for RC 4+DRE). In the total population, PCA3 discriminated better than the 4k-panel (univariate AUC: 0.63 vs 0.56; p = 0.05). There was no statistically significant difference between the multivariable model with PCA3 (AUC: 0.73) versus the model with the 4k-panel (AUC: 0.71; p = 0.18). The multivariable model with PCA3 performed better than the reference model (0.73 vs 0.70; p = 0.02). Decision curves confirmed these patterns, although numbers were small.

Conclusions

Both PCA3 and, to a lesser extent, a 4k-panel have added value to the DRE-based ERSPC RC in detecting PCa in prescreened men.

Patient summary

We studied the added value of novel biomarkers to previously developed risk prediction models for prostate cancer. We found that inclusion of these biomarkers resulted in an increase in predictive ability.  相似文献   
994.
995.
996.

Background

Organ procurement and transplant activity from controlled donation after circulatory death (DCD) was evaluated over an 11-year period to determine whether this program influenced the transplant and donation after brain death (DBD) activities.

Material and Methods

Deceased donor (DD) procurement and transplant data were prospectively collected in a local database for retrospective review.

Results

There was an increasing trend in the potential and actual DCD numbers over time. DCD accounted for 21.9% of the DD pool over 11 years, representing 23.7% and 24.2% of the DD kidney and liver pool, respectively. The DBD retrieval and transplant activity increased during the same time period. Mean conversion rate turning potential into effective DCD donors was 47.3%. Mean DCD donor age was 54.6 years (range, 3–83). Donors ≥60 years old made up 44.1% of the DCD pool. Among referred donors, reasons for nondonation were medical contraindications (33.7%) and family refusals (19%). Mean organ yield per DCD donor was 2.3 organs. Mean total procurement warm ischemia time was 19.5 minutes (range, 6–39). In 2012, 17 DCD and 37 DBD procurements were performed in the Liege region, which has slightly >1 million inhabitants.

Conclusions

This DCD program implementation enlarged the DD pool and did not compromise the development of DBD programs. The potential DCD pool might be underused and seems to be a valuable organ donor source.  相似文献   
997.
998.
Several recent studies suggest that obesity may be a risk factor for fracture. The aim of this study was to investigate the association between body mass index (BMI) and future fracture risk at different skeletal sites. In prospective cohorts from more than 25 countries, baseline data on BMI were available in 398,610 women with an average age of 63 (range, 20–105) years and follow up of 2.2 million person‐years during which 30,280 osteoporotic fractures (6457 hip fractures) occurred. Femoral neck BMD was measured in 108,267 of these women. Obesity (BMI ≥ 30 kg/m2) was present in 22%. A majority of osteoporotic fractures (81%) and hip fractures (87%) arose in non‐obese women. Compared to a BMI of 25 kg/m2, the hazard ratio (HR) for osteoporotic fracture at a BMI of 35 kg/m2 was 0.87 (95% confidence interval [CI], 0.85–0.90). When adjusted for bone mineral density (BMD), however, the same comparison showed that the HR for osteoporotic fracture was increased (HR, 1.16; 95% CI, 1.09–1.23). Low BMI is a risk factor for hip and all osteoporotic fracture, but is a protective factor for lower leg fracture, whereas high BMI is a risk factor for upper arm (humerus and elbow) fracture. When adjusted for BMD, low BMI remained a risk factor for hip fracture but was protective for osteoporotic fracture, tibia and fibula fracture, distal forearm fracture, and upper arm fracture. When adjusted for BMD, high BMI remained a risk factor for upper arm fracture but was also a risk factor for all osteoporotic fractures. The association between BMI and fracture risk is complex, differs across skeletal sites, and is modified by the interaction between BMI and BMD. At a population level, high BMI remains a protective factor for most sites of fragility fracture. The contribution of increasing population rates of obesity to apparent decreases in fracture rates should be explored. © 2014 American Society for Bone and Mineral Research.  相似文献   
999.

Purpose

To determine the usefulness of acquiring extension radiographs for the evaluation of the degree of spondylolisthesis.

Methods

Routine radiographs of the lumbar spine were retrospectively evaluated in 87 patients (mean-age 63, range 32–86) by two independent radiologists. All patients received radiographs in standing neutral, flexion and extension position. Vertebral body depth, sagittal translational displacement and lordosis angle were measured and slip percentage (SP) was calculated on standing neutral, flexion and extension radiographs. Statistical analysis was performed with a two-sided t test. Inter- and intraobserver reliability was assessed using the kappa-coefficient.

Results

There was no statistically significant SP-difference between neutral standing and extension images. Ventral instability was diagnosed in 25–34 % (cut-off >8 % SP-difference) for neutral versus flexion comparison. The detection rate of flexion–extension radiographs representing the extremes of motion was lower with 15–22 %. Inter- and intraobserver reliability was good to excellent.

Conclusion

Slip percentage in routine standing extension radiography ultimately does not differ from that obtained in a static neutral standing view. Extension radiography may therefore be omitted in a routine work-up of ventral instability in lumbar spondylolisthesis.  相似文献   
1000.
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