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51.
目的:分析腹腔镜胆囊切除术中或术后发现意外胆囊癌的临床特点,探讨其诊治措施。方法:回顾性分析2008年1月~2012年12月在我院行腹腔镜胆囊切除术治疗发现的意外胆囊癌患者共计32例的临床资料和随访结果。结果:24例患者经术中快速冷冻病理证实,其中12例中转开腹行胆囊癌根治术;8例患者经术后病理证实,6例行二次开腹手术。Nevin I期4例,Nevin II期20例,Nevin III期5例,Nevin IV期2例,Nevin V期1例。32例患者均顺利出院,住院时间6~24d,平均住院时间(13.8±8.1)d。32例中有30例获得随访,2例失访,随访时间2~49个月,平均(24.2±14.6)个月。生存23例,死亡7例,分别死于术后2、3、5、12、14、18和32个月。术后有5例患者出现并发症,2例胆囊积液,2例切口感染和1例胆瘘,经对症治疗后好转。结论:加强对胆囊癌的警惕与认识,腹腔镜胆囊切除术中或术后发现意外胆囊癌后应根据具体情况,选择最佳手术方式治疗,提高根治切除率,延长患者生存期。  相似文献   
52.
Gallbladder cancer (GBC) is the leading malignancy of biliary system showing refractory chemoresistance to current first‐line drugs. Growing epidemiological evidences have established that the incidence of GBC exhibits significant gender predominance with females two‐threefold higher than males, suggesting oestrogen/oestrogen receptors (ERs) signalling might be a critical driver of tumorigenesis in gallbladder. This study aims to evaluate the antitumour activity of tamoxifen (TAM), a major agent of hormonal therapy for breast cancer, in preclinical GBC model. Quantitative real‐time PCR was used to investigate mRNA levels. Protein expression was measured by immunohistochemistry and Western blot. Glycolytic levels were measured by glucose consumption and lactic acid measurement. The antitumour activity of TAM alone or with cisplatin was examined with CCK8 assay, colony formation, flow cytometry and in vivo models. The results revealed that ERɑ expression was higher in GBC tissues and predicted poor clinical outcomes. TAM was showed effective against a variety of GBC cell lines. Mechanical investigations revealed that TAM enabled potent reactive oxygen species (ROS) production by reduced nuclear factor Nrf2 expression and its target genes, leading to the activation of AMPK, which subsequently induced impaired glycolysis and survival advantages. Notably, TAM was demonstrated to sensitize GBC cells to cisplatin (CDDP) both in vitro and in vivo. In agreement with these findings, elimination of oestrogens by ovariectomy in nude mice prevented CDDP resistance. In summary, these results provide basis for TAM treatment for GBC and shed novel light on the potential application of endocrine therapy for patients with GBC.  相似文献   
53.
Rac GTPase activating protein 1 (RACGAP1) has been characterized in the pathogenesis and progression of several malignancies, however, little is known regarding its role in the development of gallbladder cancer (GBC). This investigation seeks to describe the role of RACGAP1 and its associated molecular mechanisms in GBC. It was found that RACGAP1 was highly expressed in human GBC tissues, which was associated to poorer overall survival (OS). Gene knockdown of RACGAP1 hindered tumor cell proliferation and survival both in vitro and in vivo. We further identified that RACGAP1 was involved in DNA repair through its binding with DNA ligase 3 (LIG3), a crucial component of the alternative-non-homologous end joining (Alt-NHEJ) pathway. RACGAP1 regulated LIG3 expression independent of RhoA activity. RACGAP1 knockdown resulted in LIG3-dependent repair dysfunction, accumulated DNA damage and Poly(ADP-ribosyl) modification (PARylation) enhancement, leading to increased apoptosis and suppressed cell growth. We conclude that RACGAP1 exerts a tumor-promoting role via binding LIG3 to reduce apoptosis and facilitate cell growth in GBC, pointing to RACGAP1 as a potential therapeutic target for GBC.  相似文献   
54.
Zhong XY  Yu JH  Zhang WG  Wang ZD  Dong Q  Tai S  Cui YF  Li H 《Gene》2012,493(1):44-51
MicroRNAs (miRNAs) are involved in the development of most cancers. However, few studies have been conducted to determine their relationship to biliary tract cancer (BTC). Farnesoid X receptor (FXR) has been reported to be a tumor suppressor for hepatocellular carcinoma and breast cancer; but few studies have focused on its correlation with BTC. In this study, we identified miR-421 as a potential regulator of FXR expression. We found that their expression amount was inversely correlated as FXR was aberrantly down-regulated in both primary tumor specimens and cell lines; while miR-421 was significantly up-regulated. Ectopic expression of miR-421 significantly decreased FXR protein concentration in BTC cells and promoted cell proliferation, colony formation and migration in vitro. Furthermore, a decrease in miR-421 expression induced G0/G1 cell cycle arrest. In conclusion, our study identified microRNA-421 functions as an oncomiR in BTC by targeting FXR. This finding may provide a novel therapeutic strategy for treatment of biliary tract cancer.  相似文献   
55.
朝医药是朝鲜民族在长期生活经验中总结出的抵抗病邪的智慧结晶,其理论核心是四象医学,在治疗上,倡导"药乃局限于人"的药性观。熊胆是熊科动物黑熊或棕熊的胆汁,其性味苦、寒,具有清热解毒,明目,止痉的功效。在朝医药中,熊胆属于太阴人药,具有活血化瘀,发汗等作用。通过对熊胆在临床上的应用以及有关其基础的研究,发现在药物的应用方面朝医药与中医药之间存在着有些差异,这种差异给药物的基础研究以及临床应用开辟了更多新思路,可使各民族医药之间取长补短。  相似文献   
56.
Summary Protamine, a naturally occurring arginine-rich polycationic protein (pI 9.7 to 12), was tested inNecturus gallbladder using a transepithelial AC-impedance technique. Protamine sulfate or hydrochloride (100 g/ml=20 m), dissolved in the mucosal bath, increased transepithelial resistance by 89% without affecting the resistance of subepithelial layers. At the same time, transepithelial voltage ( ms ) turned from slightly mucosapositive values to mucosa-negative values of approximately +1 to –5 mV. The effect of protamine on transepithelial resistance was minimal at concentrations below 5 g/ml but a maximum response was achieved between 10 and 20 g/ml. Resistance started to increase within 1 min and was maximal after 10 min. These effects were not inhibited by serosal ouabain (5×10–4 m) but could be readily reversed by mucosal heparin. The sequence of protamine effect and heparin reversal could be repeated several times in the same gallbladder. Mucosal heparin, a strong negatively charged mucopolysaccharide, or serosal protamine were without effect. Mucosal protamine reversibly decreased the partial ionic conductance of K and Na by a factor of 3, but did not affect Cl conductance. Net water transport from mucosa to serosa was reversibly increased by 60% by protamine. We conclude that protamine reversibly decreases the conductance of the cation-selective pathway through the tight junction. Although this effect is similar to that reported for 2,4,6-triamino-pyrimidinium (TAP), the mechanism of action may differ. We propose that protamine binds to the apical cell membrane and induces a series of intracellular events which leads to a conformational alteration of the tight junction structure resulting in decreased cationic permeability.  相似文献   
57.
Summary A simple numerical model for theNecturus gallbladder epithelium is presented. K+, Na+ and Cl cross the mucosal and serosal membranes as well as the junctions by means of electrodiffusion; furthermore the mucosal membrane contains a neutral entry mechanism for NaCl and the serosal membrane contains an active pump for K+ and Na+. The values which have been used for the model are taken from the literature. The model can only attain steady states if the resistance of the serosal membrane is lower than 1000 cm2. Values reported in the literature for the resistance of this membrane vary from about 3000 to about 100 cm2. We shall argue, however, that the higher estimates are in error because they are derived from a model of the tissue in which each membrane and the junction are modeled by a resistor; this procedure is invalid because the resistance of the lateral intercellular space relative to the resistance of the tight junctions is neglected and consequently the resistance of the serosal membrane is overestimated by a factor of about four. Apart from predicting a realistic steady state at normal external concentrations the model can predict quantitatively several experimental results obtained from the living epithelium. We have focused on the experiments which test the permeabilities of the serosal membrane and the properties of the pump:i) Replacement of serosal Cl by an impermeant ion.ii) Replacement of serosal K+ by Na+.iii) Inhibiting the (Na+, K+)-pump. The best correspondence between model and experiments is obtained when the pump is assumed to be electrogenic (or rheogenic) with a ratio of coupling between Na+ and K+ of 32. In this case both model and direct experiments (also presented in this paper) show an initial abrupt depolarization of 6 to 7 mV. The model also shows that it cannot be concluded fromi andii that the Cl permeability of the serosal membrane is low. The model explains, even with high passive Cl permeabilities, why the intracellular Cl concentration is relatively unaffected by paracellular currents, a fact which in other epithelia has been taken as an implication of a low Cl permeability of the serosal membranes.  相似文献   
58.
Summary The effect of bicarbonate (HCO3) on fluid absorption by guinea pig gallbladder was investigatedin vitro. Stimulation of fluid absorption was concentration dependent resulting in a fourfold increase in transport over the range 1 to 50mm. Phosphate, Tris, glycodiazine and glutamine buffers failed to substitutte for HCO3 in stimulating absorption. Unidirectional22Na fluxes were measured across short-circuited sheets of guinea pig and rabbit gallbladders mounted in Ussing-type chambers. In both species the net Na flux was unaffected by serosal HCO3 alone but was stimulated by addition of HCO3 to the mucosal bathing solution. Transepithelial electrical potential difference in rabbit gallbladder was about 1.4 mV (lumen positive) when HCO3 was present in the mucosal or in both compartments. This fell to 0.2 mV under HCO3-free conditions or when HCO3 was present only in the serosal solution. The respective values for guinea pig gallbladder were –1.6 and –0.6 mV (lumen negative). HCO3 stimulation of Na absorption by guinea pig gallbladder was abolished by increasing the bathing pH from 7.4 to 7.8, an effect resulting mainly from a reduction inJ mis Na . Tris buffer (25mm) inhibited HCO3-dependent fluid absorption in this species completely at pH 8.5 and partially at 7.5. These results indicate that HCO3 stimulates gallbladder transport in both species by an action from the mucosal side. This effect cannot be attributed to simple buffering of H+ but may be explained by the participation of HCO3 in the maintenance of intracellular H+ for a Na/H-exchange.  相似文献   
59.
Summary The paracellular conducting pathway of theNecturus gallbladder was studied with electrophysiological and electromicroscopic methods. The first one consists of the passage of short (5 msec) and small (32 A cm–2) current pulses associated with a voltage scanning of the plane of the epithelium at the apical surface with a microelectrode to detect the regions where current flows. The procedure shows that (a) the conductance is evenly distributed along the intercellular regions along the intercellular spaces of the cells where occluding junctions are located; (b) the field above the occluding junctions has the shape of a bell, so that the junction can be sensed at 1–2 m from the region where the intercellular space is visualized by light microscopy; (c) the intersections between three cells, in spite of having 3 half-junctions contributing (instead of two), do not have a higher conductance than the rest of the occluding junction. Scanning electron microscopy shows that (a) cells are densely covered by microvilli which interdigitate above the region of the occluding junctions, and (b) are covered by a surface coat. With transmission electron microscopy, (a) the opening of the occluding junctions at the apical border appears irregular, and most of them oblique; (b) in the last microns the actual mouth of the junction may deviate from the course of the interspace. Freeze-fracture replicas indicate that (a) the occluding junction has a uniform width and little variations in the number of strands around the cell, except (b) at intersections between 3 cells where both, its width and the number of strands, increase toward the basal region.  相似文献   
60.
Summary A continuous cell line, COLO 346, was established from a liver metastasis in a patient with adenocarcinoma of the gallbladder. COLO 346 grew as an adherent monolayer of pleomorphic epithelioid cells. COLO 346 cells produced esterone, but no estradiol, progesterone, or cortisol. No adrenocorticotropic hormone, β-subunit of human chorionic gonadotropin, carcinoembryonic antigen, or α-fetoprotein production by the cells was detected. Cell doubling time was 36 h. Seven allelic isozymes were assayed. COLO 346 had a chromosome mode of 74 at 21 months postestablishment with 6 marker chromosomes present in 100% of the cells analyzed. COLO 346 has been in continuous culture for over 2 yr and is available to other investigators for their studies. This paper was presented in part at the 31 st Annual Meeting of the Tissue Culture Association, June 1–5, 1980. The work was supported by Grants CA15018 and CA29514 from the National Cancer Institute, and by the Mary B. and L. H. Marshall Fund.  相似文献   
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