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51.
  目的 为规范化种植盐生肉苁蓉药材的质量研究提供基础研究资料。 方法 选择 RP-HPLC 建立盐生肉苁蓉补肾助阳功能特征成分的指纹图谱,并进行栽培品与野生品、不同生长期、不同药用部位指纹图谱的比较研究,采用计算机辅助相似度评价软件分析了相似度。 结果 种植基地药材的指纹图谱具有较高的相似度,其化学组成相似,相对比例也基本稳定。不同生长期和不同部位药材的指纹图谱也具有较好的一致性,但特征峰的含量存在明显差异。 结论 利用 RP-HPLC 指纹图谱可以较为全面地反映盐生肉苁蓉补肾助阳功能整体特征成分的内在质量,方法重现性好。  相似文献   
52.
新疆石榴皮化学成分研究   总被引:6,自引:0,他引:6  
目的:研究新疆石榴皮(Punica granatum)的化学成分.方法:采用薄层色谱、硅胶柱色谱、MCI-gel CHP20P、Sephadex LH-20凝胶柱色谱等方法进行分离纯化,使用波谱分析技术和理化常数对照等方法对得到的化合物进行结构鉴定.结果:分离得到了10个化合物,分别为:没食子酸(1)、没食子甲酯(2)、鞣花酸(3)、(+)-儿茶素(4)、异槲皮苷(5)、D-甘露醇(6)、熊果酸(7)、齐墩果酸(8)、β-谷甾醇(9)、胡萝卜苷(10).结论:化合物1~10均、为首次从该植物中分离得到.  相似文献   
53.

Background

Biliopancreatic diversion with duodenal switch (DS) is known to be superior in weight loss to other bariatric procedures, but with the disadvantage of increased complication rates. Single-anastomosis duodenal-ileal bypass (SADI-S) is reported to have similar weight loss with lower complication rates compared with traditional DS.

Objectives

The aim of this study was to compare weight loss and complication rate between SADI-S and double-anastomosis DS at a single institution.

Setting

Academic hospital, United States.

Methods

A retrospective chart review was performed on 185 patients who underwent laparoscopic or robot-assisted laparoscopic DS between March 1, 2015 and December 10, 2017. A total of 111 patients had SADI-S, and 74 patients underwent double-anastomosis DS.

Results

Baseline patient characteristics were comparable between the 2 groups. The mean preoperative body mass index was 56.3 kg/m2 and 54.4 kg/m2 in SADI-S and double-anastomosis DS patients, respectively. Thirteen (11.7%) and 4 (5.4%) patients were readmitted within 30 days after SADI-S and double-anastomosis DS, respectively (P?=?.16). Percentage of total weight loss was 22.0%, 38.5%, and 44.2% in the SADI-S group and 20.2%, 38.0%, and 48.4% in the double-anastomosis DS group at 6, 12, and 24 months, respectively. The majority of patients had vitamin A and E levels in the normal range. However, 40% to 60% of the patients had low levels of vitamin D after the procedure.

Conclusions

SADI-S and double-anastomosis DS are comparable in terms of weight loss and complication rate. However, close nutritional follow-up is warranted for both procedures.  相似文献   
54.
55.
BACKGROUND: Systematic analysis of the influence of diet on the initiation and progression of prostate cancer is often difficult in human populations, for which dietary variables overlap a diversity of genetic backgrounds and social behaviors. Animal models that emulate human prostate cancer allow experimental analysis of the mechanisms of action of nutritional agents that show anti-prostate cancer activity. METHODS: We have used an orthotopic implant model to characterize the in vivo response of androgen-sensitive LNCaP prostate tumors to three well-characterized soy dietary supplements: isoflavone depleted soy protein, soy phytochemical concentrate (SPC), and genistin. RESULTS: In male SCID mice orthotopically implanted with the androgen-sensitive human prostate cell line LNCaP, dietary supplements of soy protein, genistin, and SPC reduced primary tumor weight by 42% (P = 0.07), 57% (P < 0.05) and 70% (P < 0.005), respectively. All three soy supplements significantly increased tumor apoptosis and decrease microvessel density, with no significant change in tumor proliferation. Each supplement produced a distinct serum androgen response, with genistin producing the greatest decrease in total serum testosterone and dihydrotestosterone (DHT) (P < 0.05) and the greatest increase in testosterone to DHT ratio (P < 0.05) and soy protein the greatest decrease in bioactive androgen (P < 0.05). Only SPC significantly inhibited metastases to lymph nodes and lungs, and only SPC produced a significant increase in tumor p53 expression. CONCLUSION: Taken together, these data suggest that the anti-prostate cancer activity of dietary soy protein, soy phytochemicals, and genistin use different molecular pathways. In addition, we have demonstrated that this animal model can be used in the design of dietary strategies for prostate cancer prevention and therapy.  相似文献   
56.
A series of novel compounds have been designed that are potent inhibitors of poly(ADP-ribose) polymerase-1 (PARP-1), and the activity and physical properties have been characterized. The new structural classes, 3,4,5,6-tetrahydro-1H-azepino[5,4,3-cd]indol-6-ones and 3,4-dihydropyrrolo[4,3,2-de]isoquinolin-5-(1H)-ones, have conformationally locked benzamide cores that specifically interact with the PARP-1 protein. The compounds have been evaluated with in vitro cellular assays that measure the ability of the PARP-1 inhibitors to enhance the effect of cytotoxic agents against cancer cell lines.  相似文献   
57.
Growth factors, including nerve growth factor (NGF), have been hypothesized to play a role in resistance to chemotherapeutic agent-induced apoptosis. Induction by NGF of resistance to apoptosis is primarily thought to be the result of its binding to its high-affinity receptor, TrkA. The low-affinity NGF receptor, p75, has long been thought merely to facilitate NGF binding to TrkA. However, we have previously shown that the binding of NGF to its low-affinity receptor, p75, protects neuroblastoma cells that do not express TrkA against apoptosis induced by enediyne chemotherapeutic agents. In cells that express both receptors, it is not clear what determines which receptor is responsible for the protective effect of NGF. We now show that, in enediyne-treated SH-SY5Y neuroblastoma transfectants with native levels of p75 and a low TrkA/p75 ratio (1/100), the anti-apoptotic effect of NGF requires binding to p75. In contrast, in transfectants with native levels of p75 and a high TrkA/p75 ratio (100/100), NGF treatment prevents enediyne-induced apoptosis by a mechanism independent of p75 binding. Treatment of low TrkA/p75 ratio cells with NGF results in activation and nuclear translocation of NF-kappaB and tyrosine phosphorylation of TrkA. Analogous treatment of high TrkA/p75 ratio cells results only in phosphorylation of TrkA even though nuclear factor (NF)-kappaB signaling is not inactive and can be initiated by other ligands. The ratio of TrkA/p75 in cells that express both receptors probably contributes to the determination of which of the two known roles of p75 (i.e., TrkA independent or TrkA facilitatory) are responsible for NGF-mediated protection from enediyne-induced apoptosis.  相似文献   
58.
Rogers J  Strohmeyer R  Kovelowski CJ  Li R 《Glia》2002,40(2):260-269
There is now abundant evidence that brain microglia, when activated, have the lineage, receptors, and synthetic capacity to participate in both potentially neurotoxic inflammatory responses and potentially beneficial phagocytic responses. Amyloid beta peptide (Abeta) forms highly insoluble, beta-pleated aggregates that are widely deposited in the Alzheimer's disease (AD) cortex and limbic system. Aggregated Abeta also activates the classical and alternative complement cascades. These properties make Abeta an excellent target for microglial phagocytosis, a view supported by multiple reports, through well established mechanisms of phagocyte clearance.  相似文献   
59.
Solitary fibrous tumors (SFT) of the pleura are a rare neoplasm, with benign biological behaviour. Recurrences are rare, and no distant metastases are described in the literature. SFT can secrete hormone-like substances, responsible for paraneoplastic syndromes. The authors describe a case of severe hypoglycaemia due to insulin-like growth factor II (IGF-2)'s secretion by a giant SFT of the pleura. Hypoglycaemia was controlled by the resection of the tumor. Diagnosis and surgical management of these neoplasms are also discussed.  相似文献   
60.
BACKGROUND: This study aims to evaluate the efficacy of video-assisted thoracoscopic surgery (VATS) pleurodesis in the treatment of spontaneous pneumothorax with particular reference to the postoperative period and the rate of recurrence after pleural abrasion. METHODS: One hundred and thirty-three patients who underwent VATS management of primary spontaneous pneumothorax were retrospectively reviewed. They were 113 males and 20 females with median age of 26 (range 12-37). Among these patients, 114 underwent VATS for recurrent pneumothorax and 19 for persistent air-leakage at the first episode. During surgical procedure, in 78% of cases, parenchymal blebs were identified and resected by stapler resection. All patients were submitted to pleural abrasion. RESULTS: No intra- or postoperative deaths occurred. Postoperative complications were persistent air-leak for more than 7 days in 6 patients (4.3%) bleeding in 3 patients (2.2%). The median chest-tube duration and hospital stay were 2 (range 2-11) and 3 (range 3-12) days, respectively. Median follow-up period of 53 (range 6-96) months was complete for all patients. Five episodes of recurrent pneumothorax were encountered and 4 of them, because of major entity, required re-do VATS with stapler resection and pleural abrasion: their postoperative period and residual follow-up was uneventful. CONCLUSIONS: The goal in the surgical management of spontaneous pneumothorax, which often affects "apparently healthy" young patients, is to secure the less recurrence rate with no mortality and quite null morbidity and functional impairment. VATS stapler resection and pleural abrasion is a safe procedure allowing a good management of the disease with low complication rate, short chest-drain duration, hospital stay and recurrence rate quite similar to those referred for other procedures such as pleural poudrage or limited pleurectomy.  相似文献   
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