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41.
Saw palmetto supplements are one of the most commonly consumed supplements by men with prostate cancer and/or benign prostatic hyperplasia (BPH). Some studies have found significant improvements in BPH and lower urinary tract symptoms (LUTS) with saw palmetto supplementation, whereas others found no benefits. The variation in the efficacy in these trials may be a result of differences in the putative active components, fatty acids and phytosterols, of the saw palmetto supplements. To this end, we quantified the major fatty acids (laurate, myristate, palmitate, stearate, oleate, linoleate) and phytosterols (campesterol, stigmasterol, β-sitosterol) in 20 commercially available saw palmetto supplements using GC-FID and GC-MS, respectively. Samples were classified into liquids, powders, dried berries, and tinctures. Liquid saw palmetto supplements contained significantly higher (p < 0.05) concentrations of total fatty acids (908.5 mg/g), individual fatty acids, total phytosterols (2.04 mg/g), and individual phytosterols, than the other supplement categories. Powders contained significantly higher (p < 0.05) concentrations of total fatty acids than tinctures, which contain negligible amounts of fatty acids (46.3 mg/g) and phytosterols (0.10 mg/g). Our findings suggest that liquid saw palmetto supplements may be the best choice for individuals who want to take a saw palmetto supplement with the highest concentrations of both fatty acids and phytosterols.  相似文献   
42.
Context and objective: Viperid venom-induced chronic local-toxicity continues even after anti-snake venom treatment. Therefore, traditional antidote Albizia lebbeck L. (Fabaceae) seed extract was tested against Echis carinatus S. (Viperidae) venom (ECV)-induced local toxicity to evaluate its complementary remedy.

Materials and methods: Soxhlet extraction of A. lebbeck seeds was performed with the increasing polarity of solvents (n-hexane to water); the extract was screened for phytochemicals (alkaloids, anthraquinones, flavonoids, glycosides, phenolics, saponins, steroids and tannins). In preliminary in vitro analysis, A. lebbeck methanolic extract (ALME) demonstrated significant inhibition of ECV proteases, the major enzyme–toxin responsible for local- toxicity. Therefore, in vitro neutralizing potential of ALME was further evaluated against hyaluronidases and phospholipase A2 (1:1–1:100 w/w). In addition, alleviation of ECV induced characteristic local- toxicity [haemorrhage (i.d.) and myotoxicity (i.m.)] was determined in mice.

Results: ALME contained high concentrations of phenolics and flavonoids and demonstrated significant in vitro inhibition of ECV protease (IC50?=?36.32?μg, p?<?0.0001) and hyaluronidase (IC50?=?91.95?μg, p?<?0.0001) at 1:100 w/w. ALME significantly neutralized ECV induced haemorrhage (ED50?=?26.37?μg, p?<?0.0001) and myotoxicity by significantly reducing serum creatinine kinase (ED50?=?37.5?μg, p?<?0.0001) and lactate dehydrogenase (ED50?=?31.44?μg, p?=?0.0021) levels at 1:50 w/w.

Discussion and conclusion: ALME demonstrated significant neutralization of ECV enzymes that contribute in local tissue damage and haemostatic alterations. The study scientifically supports the anecdotal use of A. lebbeck in complementary medicine and identifies ALME as principle fraction responsible for antivenom properties.  相似文献   
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44.
Benign prostate hyperplasia (BPH) is a common condition affecting older men, with an incidence that is age‐dependent. Histological BPH, which typically develops after the age of 40 years, ranges in prevalence from >50% at 60 years to as high as 90% by 85 years of age. Typical symptoms include increased frequency of urination, nocturia, urgency, hesitancy, and weak urine stream. Conventional medicines used for the treatment of BPH include alpha blockers and 5‐alpha reductase inhibitors. This articles review the mode of action, the efficacy, and the safety, including herb‐drug interactions of the most common botanicals (Serenoa repens, Pygeum africanum, Urtica dioica, and Cucurbita pepo) and nutraceuticals (isoflavones, lycopene, selenium, and β‐Sitosterol) in controlling the lower urinary tract symptoms associated to BPH. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
45.

Background

The Dynamic Hip Screw is well established for the treatment of femoral neck fractures. However, cut-out occurs in 1–6% of all cases. This study compared the biomechanical performance of a helical shaped implant (DHS-Blade) to the Dynamic Hip Screw in an unstable femoral neck fracture model.

Methods

Ten pairs of human cadaveric femora were either instrumented with a DHS-Blade or a Dynamic Hip Screw. Osteotomies were created using a custom-made saw-guide. Cyclic loading was performed by introducing in vivo measured load-trajectories to the femoral head. Starting at 1500 N, the load was stepwise increased until failure of the construct. Radiographs were taken in 5000 cycles increments to identify onset of femoral head migration with respect to the implant. A survival analysis was performed on the cycles to onset of migration. A paired t-test was carried out on the displacements of the femoral head relative to the shaft as determined by optical motion tracking.

Findings

One hundred percent migrations occurred for the Dynamic Hip Screw compared to 50% for the DHS-Blade. The survival probability in terms of implant anchorage was found higher for the blade (P = 0.023). However, significant higher deformation of the repair construct was observed for the DHS-Blade (P = 0.004).

Interpretation

The study showed superior implant anchorage of the DHS-Blade compared to the DHS, which might reduce the cut-out risk. Nevertheless, the blade allowed higher deformation of the femur mainly resulting in shortening of the neck, which might be due to a systematic loss of fracture reduction.  相似文献   
46.
PURPOSE: To evaluate motion correction effect and image quality in the upper abdomen with the periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) (BLADE) and parallel imaging acquisition technique. MATERIALS AND METHODS: A total of 50 consecutive patients underwent abdominal MR imaging. Fat-saturated T2-weighted turbo spin-echo sequences were obtained by respiratory triggering. The subjects were examined with three different conditions of echo train length (ETL), blade width, and percent k-space coverage in the same scanning time: 19/30/100%, 30/30/100%, and 30/52/175%, which were designated as L/C(1), L/C(2), and L/C(3), respectively. The parallel imaging acquisition technique was used to either reduce ETL from 30 to 19 in L/C(1) or increase k-space coverage from 100% to 175% in L/C(3) compared with L/C(2). Motion and streak artifacts, and overall image quality were evaluated visually by two radiologists, independently. RESULTS: Motion and streak artifacts were mostly reduced in L/C(3) condition. The L/C(3) image also gave the best overall image quality compared with other conditions (P < 0.001). The inter-rater reliability for each evaluation agreed well. CONCLUSION: In upper abdominal BLADE MRI, it was possible to reduce image artifacts and obtain better image quality by increasing the k-space coverage with parallel imaging in the same scanning time.  相似文献   
47.
在腰椎手术术后稳定性的重建中,后路椎间植骨融合是一种较其它脊柱融合术更为理想的脊柱融合方法。然而目前常用的术式仍存在一些缺陷,如能自体取骨效果最好,但取骨增加了手术时间和手术并发症;异体骨移植和使用椎间融合器效果虽好,但增加医疗费用,同时异体骨移植还可能传播疾病。因此,我们尝试探求一种有效而且经济的手术方法——环锯加盖植骨法。  相似文献   
48.
In the field of spinal tumors, intralesional tumor cutting is sometimes inevitable. The purpose of this study was to compare the potential for tumor growth after intralesional cutting by T-saw, Gigli saw, and scalpel. Tumors, prepared by the subcutaneous injection of human HT 1080 fibrosarcoma cells in nude mice, were harvested and cut with a T-saw, Gigli saw, or scalpel. A 3-cm wound was created in the skin on the back in another group of nude mice. The cut surface of the tumor was rubbed for 10 s against the subcutaneous tissue in this second group of nude mice. In the same manner, the instrument used for tumor cutting was rubbed against the subcutaneous tissue in the 3-cm wound in the back of a third group of nude mice for 10 s. Other instruments used for tumor cutting were immediately washed in culture medium, and the total number of tumor cells was counted. Tumor blocks and single-cell suspensions prepared from tumor tissues of the same weight were inoculated and injected into a fourth group of nude mice. The incidence of tumor growth after the rubbing of the subcutaneous tissue with the tumor surface cut with a T-saw, Gigli saw, and scalpel was 16.7%, 50.0%, and 33.3%, respectively. The corresponding figures after the rubbing of the subcutaneous tissue with a T-saw, Gigli saw, and scalpel was 16.7%, 33.3%, and 33.3%, respectively. The mean numbers of tumor cells attached to the T-saw, Gigli saw, and scalpel were 1.88 × 105, 5.02 × 105, and 4.92 × 105, respectively. Finally, the incidence of tumor growth after the inoculation of tumor blocks and single-cell suspensions was 100% and 77.8%, respectively. These findings show that tumor recurrence is less likely after intralesional tumor cutting with a T-saw than after such cutting with a Gigli saw or scalpel. Received: January 25, 2001 / Accepted: April 16, 2001  相似文献   
49.
目的探讨肩胛骨骨折手术入路的选择及分析临床应用效果。方法从1997年7月—2009年1月对31例肩胛骨骨折患者采用三种不同的手术入路进行内固定,对比其临床适应证,分析治疗效果。结果 31例患者全部得到随访,按照Constant的评定标准:优22例,良6例,可3例,优良率为90.3%。结论肩胛骨骨折通过手术治疗可获得良好的疗效,不同的骨折类型应采用不同手术入路,可获得更好的治疗效果。  相似文献   
50.
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