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31.
32.
Polybrominated diphenyl ethers (PBDEs) are a group of aromatic organic bromine compounds, which have been used in a broad array of polymeric materials (plastics, foams, resins, and adhesives) as brominated flame retardants. They are used in commercial and household products, including textiles, electronic equipment, airplanes, and automobiles, especially in China and the USA, because they are inexpensive with excellent flame-retardant effects[1]. During the past decade, over 14,000 tonnes of PBDEs have entered the market, and have become ubiquitous environmental contaminants[2].  相似文献   
33.
Han  Yuyi  Zhang  Xiaoqian  Zhou  Zhiyin  Yu  Mengxi  Wang  Qiuhong  Yao  Jin  Han  Yi 《International ophthalmology》2020,40(4):891-899
International Ophthalmology - The present study aims to determine hydrogen sulfide (H2S) concentrations of the aqueous humor from patients with diabetic retinopathy (DR) to compare its levels in...  相似文献   
34.
Acrylamide exposure impairs blood-cerebrospinal fluid barrier function   总被引:1,自引:0,他引:1  
Previous studies show that chronic acrylamide exposure leads to central and peripheral neu- ropathy. However, the underlying mechanisms remained unclear. In this study, we examined the permeability of the blood-cerebrospinal fluid barrier, and its ability to secrete transthyretin and transport leptin of rats exposed to acrylamide for 7, 14, 21 or 28 days. Transthyretin levels in cerebrospinal fluid began to decline on day 7 after acrylamide exposure. The sodium fluorescein level in cerebrospinal fluid was increased on day 14 after exposure. Evans blue concentration in cerebrospinal fluid was increased and the cerebrospinal fluid/serum leptin ratio was decreased on days 21 and 28 after exposure. In comparison, the cerebrospinal fluid/serum albumin ratio was increased on day 28 after exposure. Our findings show that acrylamide exposure damages the blood-cerebrospinal fluid barrier and impairs secretory and transport functions. These changes may underlie acrylamide-induced neurotoxicity.  相似文献   
35.
目的探讨术中x-线定位在经神经内镜下甲介型蝶窦垂体瘤手术的应用。方法回顾性分析6例甲介型蝶窦垂体瘤病人的临床资料,均采用神经内镜下垂体瘤切除结合术中X-线定位方法。结果术中X-线定位准确4例;2例发生纵向偏差,均纠正。肿瘤全切除5例,次全切除1例。术后激素水平正常,视力视野改善。出现暂时性尿崩1例,治疗后痊愈。无脑脊液鼻漏、垂体功能低下、蝶窦炎发生,无死亡病例。6例病人随访3年,均无复发。结论神经内镜技术结合术中X-线定位是一种治疗甲介型蝶窦垂体瘤的安全、有效方法。  相似文献   
36.
37.
PurposeThis study aimed to investigate the therapeutic effects and underlying mechanisms of locally delivered regulatory T cells (Tregs) on acute corneal wound healing after alkali burn.MethodsAfter corneal alkali burn, the mice were injected subconjunctivally with regulatory T cells (Tregs) isolated from syngeneic mice. The wound healing process was monitored by clinical manifestation, flow cytometry, and enzyme-linked immunosorbent assay (ELISA). As amphiregulin (Areg) was significantly upregulated, its reparative function in injured corneas was suggested. The hypothesis was further verified via loss- and gain-of-function experiments by administrating the antibody of Areg (anti-Areg) and recombinant Areg (rmAreg).ResultsSubconjunctivally injected Tregs rapidly migrated to injured corneas. The mice treated with Tregs showed prominently reduced corneal opacity, alleviated edema, and faster re-epithelialization compared with the control group. Mechanistically, Treg treatment led to suppressed infiltration of inflammatory cells, along with improved proliferation and inhibited apoptosis of corneal epithelial cells. Tregs expressed upregulated functional markers, including Areg. Expectantly, the levels of Areg in corneas were dramatically higher in the Treg injection group, in line with better corneal restoration. Additional experiments showed that the administration of anti-Areg blunted the reparative effect of Tregs, while exogenous Areg enhanced it. Treg-treated corneas also exhibited less neovascularization and fibrosis at a later reconstruction stage of corneal repair.ConclusionsThe findings showed that the subconjunctival injection of Tregs effectively promoted corneal wound healing by inhibiting excessive inflammation and enhancing epithelial regeneration, with an indispensable reparative role of Areg. Subsequent complications of corneal vascularization and fibrosis were therefore reduced.  相似文献   
38.
The aim of this study was to develop a tumour vaccine with the ability to induce and expand higher affinity cytotoxic T lymphocytes and stimulate an effective antitumour immune response. The hypothesis tested was that G422 glioblastoma cells modified with B7-1 and interferon (IFN)-gamma genes could serve as a tumour vaccine. It was found that therapeutic subcutaneous immunizations with this tumour vaccine significantly induced a cytotoxic T-cell response and prolonged the survival of female Kuming mice with intracerebral G422 tumour isografts. The data collectively suggested that G422 glioblastoma cells genetically modified with B7-1 and IFN-gamma genes could serve as a tumour vaccine.  相似文献   
39.

Purpose

Since its introduction, the Da Vinci surgical system for the treatment of gastroesophageal reflux disease (GERD) has been the subject of much controversy. Several prospective randomized controlled trials, conducted to assess its effectiveness and safety, have revealed differences. We performed this meta-analysis to evaluate the efficiency and safety of robotic Nissen fundoplication for GERD.

Methods

We performed a comprehensive search of PubMed, Embase, and OVID-MEDLINE, from 1950 to the present, with daily updates generated by a computer, to identify all published papers on robotic Nissen fundoplication for the treatment of GERD. The meta-analysis was performed by Review Manager Version 5.0. Differences of the overall effect were considered significant at P < 0.05 with a 95 % confidence interval (95 % CI).

Results

Five studies with a collective total of 160 patients were included. Apart from intra-operative and post-operative complications, which were excluded because of incomplete primary data, there were no significant differences in outcomes, including of total operation interval (P = 0.16), effective operation interval (P = 0.95), post-operative dysphagia (P = 0.94), intra-operative conversion (P = 0.94), re-operation (P = 0.43), hospital stay (P = 0.97) and in-hospital costs (P = 0.08).

Conclusions

As current data do not clarify the advantages of the Da Vinci surgical system in Nissen fundoplication for GERD, we believe that a large a multi-center controlled trial is warranted.  相似文献   
40.

Introduction

Plate fixation is the gold standard for the treatment of forearm fractures at present, and whether or not to remove the implant after bone union remains controversial. This study demonstrated some cases of refracture in adult forearm fractures after bone union and discussed the risk factors for decision-making regarding implant removal.

Methods

We reviewed patients with forearm diaphyseal fractures (including the radius, ulna, or both bones) who received open reduction and internal fixation (ORIF) from January 2008 to May 2011 in our institute. Fracture type was classified according to the AO/OTA system. All patients were fixed with a 3.5-mm dynamic compression plate. The patients were divided into two main groups: group A received implant removal after bone union, and group B retained the implant.

Results

There were 122 patients (170 bones) included in this study (40 females and 82 males). In group A, 7/51 patients (8/62 bones; 12.9 %) had refracture. As classified by the AO/OTA classification, one patient was classified as type A1, one patient as type A2, two patients as type A3, and three patients as type B3. All patients suffered refracture without high-energy trauma. In group B, the refracture rate was 2.77 %, and all were caused by high-energy trauma. Patients with refracture had a shorter time interval between ORIF and implant removal. The possible risk factors of refracture in this study included a wedge bone defect on plain film, implant removal performed after less than 18 months, and AO/OTA type B fracture.

Conclusion

The incidence of refracture was significantly lower in the group that retained the implant. Routine implant removal after bone union in adult forearm fractures is not recommended due to the higher refracture rate.  相似文献   
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