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11.
We evaluated clinically, radiologically and surgically a series of 76 pituitary adenomas. All cases were assessed immunohistochemically and in 49 patients the PCNA monoclonal antibody was measured. The most frequent types found were the bihormonal adenomas, followed by prolactinomas and non secreting adenomas. The bihormonal adenomas, non secreting adenonas and the sub unit alfa producing adenomas were proportionally more invase as determined by radiological criteria (CTscan or MRI). In 59 patients a transphenoidal approach was used, six cases were operated on transcranially and in 11 patients we used a combination of both approach. Total resection were achieved in 32 cases, most of which were microadenomas, in 15 cases the resection was subtotal and partial in 29 cases. Diabetes insipidus was the most frequent endocrine complication. It was observed that secreting adenomas tend to be associated with an increased PCNA and invasive adenomas correlated with PCNA 3 and 4. An improvement in vision was observed in 85% of macroadenomas seen after a total, subtotal or partial resection.  相似文献   
12.
Nanotechnology experienced a great technological advance after the discovery of the graphene family (graphene – Gr, graphene oxide – GO, and reduced graphene oxide-rGO). Based on the excellent properties of these materials, it is possible to develop novel polymeric nanocomposites for several applications in our daily routine. One of the most prominent applications is for food packaging, offering nanocomposites with improved thermal, mechanical, anti-microbial, and barrier properties against gas and water vapor. This paper reviewed food packaging from its inception to the present day, with the development of more resistant and intelligent packaging. Herein, the most common combinations of polymeric matrices (derived from non-renewable and renewable sources) with Gr, GO, and rGO and their typical preparation methods are presented. Besides, the interactions present in these nanocomposites will be discussed in detail, and their final properties will be thoroughly analyzed as a function of the preparation technique and graphene family-matrix combinations.

Food packaging based on nanotechnology of polymeric nanocomposites of graphene and graphene oxide results in packaging with better thermal, mechanical, antimicrobial, electrical packaging, moisture barrier and gas properties.  相似文献   
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14.
The need for daily parenteral administration is an important limitation in the clinical use of pentavalent antimonial drugs against leishmaniasis. In this study, amphiphilic antimony(V) complexes were prepared from alkylmethylglucamides (L8 and L10, with carbon chain lengths of 8 and 10, respectively), and their potential for the oral treatment of visceral leishmaniasis (VL) was evaluated. Complexes of Sb and ligand at 1:3 (SbL8 and SbL10) were obtained from the reaction of antimony(V) with L8 and L10, as evidenced by elemental and electrospray ionization-tandem mass spectrometry (ESI-MS) analyses. Fluorescence probing of hydrophobic environment and negative-staining transmission electron microscopy showed that SbL8 forms kinetically stabilized nanoassemblies in water. Pharmacokinetic studies with mice in which the compound was administered by the oral route at 200 mg of Sb/kg of body weight indicated that the SbL8 complex promoted greater and more sustained Sb levels in serum and liver than the levels obtained for the conventional antimonial drug meglumine antimoniate (Glucantime [Glu]). The efficacy of SbL8 and SbL10 administered by the oral route was evaluated in BALB/c mice infected with Leishmania infantum after a daily dose of 200 mg of Sb/kg for 20 days. Both complexes promoted significant reduction in the liver and spleen parasite burdens in relation to those in the saline-treated control group. The extent of parasite suppression (>99.96%) was similar to that achieved after Glu given intraperitoneally at 80 mg of Sb/kg/day. As expected, there was no significant reduction in the parasitic load in the group treated orally with Glu at 200 mg of Sb/(kg day). In conclusion, amphiphilic antimony(V) complexes emerge as an innovative and promising strategy for the oral treatment of VL.  相似文献   
15.
不同剂量的荆防口服液对乙型溶血性链球菌等菌种有程度不同的抑菌作用,对大肠杆菌内毒素所致的家兔发热有明显的解热作用,对醋酸所致小鼠扭体疼痛反应有抑制作用,可使小鼠抗体滴度升高,腹腔巨噬细胞吞噬百分率及吞噬指数明显增强,对小鼠迟发型超敏反应无明显作用  相似文献   
16.
以实验性半乳糖性白内障大鼠血、房水、晶体中牛磺酸含量的变化研究了牛磺酸与白内障发病的关系。结果半乳糖性白内障大鼠血中牛磺酸含量在发病晚期明显下降。实验组较正常组减少68.17%;房水中牛磺酸含量第5,8,14天分别下降41.02%,48.30%,54.80%;晶体牛磺酸含量第5,8,14天分别下降76.91%,74.84%,85.13%。作者认为半乳糖性白内障的发病与机体血、房水、晶体中牛磺酸含量的减少有密切关系,且在白内障发病初期眼局部牛磺酸含量的减少尤为明显。  相似文献   
17.
目的探讨苯妥英钠(Diphenylhydantoin,DPH)在急性缺氧条件下的脑保护作用。方法给大鼠应用DPH,用荧光分光法检测其在低压舱模拟升空7.5km后1h、2h的脑匀浆单胺递质含量,同时观察脑细胞形态学改变。结果DPH实验组在缺氧1h及2h时脑多巴胺和5-羟色胺含量升高(P<0.05),而脑去甲肾上腺素在缺氧1h时降低(P<0.05),缺氧2h恢复正常。电镜形态学观察,低压缺氧条件下对照组大鼠脑细胞水肿,线粒体嵴严重缺失,细胞核明显变形;应用DPH的实验组细胞形态基本正常。结论给大鼠应用苯妥英钠后,在急性缺氧条件下,动物脑单胺递质含量的变化可能与缺氧适应或耐受的形成有关。  相似文献   
18.
本文报导了改良U型鲁氏棒张力带钢丝内固定治疗腰椎滑脱症32例。其中23例L5滑脱,6例L4滑脱,3例L3滑脱。26例滑脱为Ⅱ度,6例滑脱为Ⅲ度。手术后六个月,X线检查未见再滑脱  相似文献   
19.

Background

Postoperative pelvic abscesses in patients submitted to colorectal surgery are challenging. The surgical approach may be too risky, and image-guided drainage often is difficult due to the complex anatomy of the pelvis. This article describes novel access for drainage of a pelvic collection using a minimally invasive natural orifice approach.

Methods

A 37?year-old man presented with sepsis due to a pelvic abscess during the second postoperative week after a Hartmann procedure due to perforated rectal cancer. Percutaneous drainage was determined by computed tomography to be unsuccessful, and another operation was considered to be hazardous. Because the pelvic fluid was very close to the rectal stump, transrectal drainage was planned. The rectal stump was opened using transanal endoscopic microsurgery (TEM) instruments. The endoscope was advanced through the TEM working channel and the rectal stump opening, accessing the abdominal cavity and pelvic collection.

Results

The pelvic collection was endoscopically drained and the local cavity washed with saline through the scope channel. A Foley catheter was placed in the rectal stump. The patient’s recovery after the procedure was successful, without the need for further intervention.

Conclusions

Transrectal endoscopic drainage may be an option for selected cases of pelvic fluid collection in patients submitted to Hartmann’s procedure. The technique allows not only fluid drainage but also visualization of the local cavity, cleavage of multiloculated abscesses, and saline irrigation if necessary. The use of TEM instrumentation allows safe access to the peritoneal cavity.  相似文献   
20.
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