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21.
目的分析不同手术方式对Ⅳ期胆囊癌预后的影响.方法对1997年6月~2001年5月间上海市172例Ⅳ期胆囊癌病例进行临床病理分析,并对获得随访的164例的预后与手术方式的关系进行探讨.数据分析采用Kaplan-Meier法.结果 172例中未手术者44例(25.6%),手术者128例(74.4%),其中包括单纯胆囊切除术45例(35.1%)、胆囊癌根治性切除术17例(13.3%)、胆囊癌扩大根治性切除术5例(3.9%)和剖腹探查术61例(47.7%).在行根治性切除者中,Ⅳa和Ⅳb期的1年生存率分别为69.2%和40.7%,明显好于胆囊未切除或单纯切除者,在Ⅳa和Ⅳb期中各有2例存活期超过5年.结论有选择地进行Ⅳ期胆囊癌病例根治性或扩大根治性手术,有助于改善预后.  相似文献   
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目的研究上海市区居民胆道癌病理形态特征和鉴别诊断.方法自1997年6月~2001年5月在上海市区开展基于全人群的胆道癌病例-对照研究,总共收集病理切片1 228例,包括胆道癌487例(其中胆囊癌322例,肝外胆管癌105例和壶腹癌60例),胆道结石和胆囊炎对照病例721例,胆道腺瘤20例,由中、美资深病理医师复查,按世界卫生组织1991年胆囊和肝外胆管肿瘤组织学分型进行分类.结果病理标本以切除标本为主,肿瘤大小为多数小于4 cm,组织学类型中70%以上为腺癌,肿瘤组织学分级以高分化和中分化占绝大多数,TNM分期中0~Ⅱ期的胆囊癌和肝外胆管癌约占1/3,壶腹癌近2/3.病理复查结果显示诊断过头占1.8%,诊断不足占0.6%,漏诊占0.1%;随访结果显示根治术后的5年生存率:胆囊癌40.7%、肝外胆管癌11.1%和壶腹癌26.9%.结论病理复查可以统一诊断标准,提高确诊率,为全人群病例-对照研究和多学科协作积累经验.  相似文献   
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Abstract: KIF1A, a kinesin‐related motor protein that transports pre‐synaptic vesicles in neurons, was originally presumed to translocate along microtubules (MT) as a monomer. Protein structure predictions from its amino acid sequence failed to identify the long coiled‐coil domains typical of kinesins, which led researchers to believe it does not oligomerize into the canonical kinesin dimer. However, mounting evidence using recombinant chimeric protein indicates that KIF1A, like conventional kinesin, requires dimerization for fast, unidirectional processive movement along MTs. Because these studies are somewhat indirect, we wished to test the oligomerization state of native KIF1A, and to compare that to full‐length recombinant protein. We have performed hydrodynamic analyses to determine the molecular weights of the respective complexes. Our results indicate that most native KIF1A is soluble and indeed monomeric, but recombinant KIF1A is a dimer. MT‐binding studies also showed that native KIF1A did not bind to MTs in either the presence of AMP‐PNP, apyrase, or adenosine triphosphate (ATP), but recombinant KIF1A bound to MTs most stably in the presence of ATP, indicating very different motor functional states. To further characterize KIF1A's dimerization potential, we prepared peptides corresponding to the neck domains of MmKIF1A and CeUnc104, and by circular dichroism spectroscopy compared these peptides for their ability to form coiled‐coils. Interestingly, both MmKIF1A and CeUnc104 neck peptides formed homodimeric coiled‐coils, with the MmKIF1A neck coiled‐coil exhibiting the greater stability. Collectively, from our data and from previous studies, we predict that native KIF1A can exist as both an inactive monomer and an active homodimer formed in part through its neck coiled‐coil domain.  相似文献   
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Systematic disinfection of the stethoscope diaphragm is required to ensure that it does not act as a vector for cross-transmission of health-related diseases. Thus, an antimicrobial latex film could be used as a cover to inhibit pathogenic bacteria from growing on its surface. The aim of this work is to determine the antimicrobial activity and mechanical properties of antimicrobial natural rubber (NR) latex films with different types of antimicrobial agents (mangosteen peel powder (MPP), zinc oxide nanoparticles (ZnO NP), and povidone-iodine (PVP-I)). The antimicrobial loading was varied from 0.5, to 1.0, and 2.0 phr to monitor the effective inhibition of Gram-negative bacteria and fungi growth. For MPP and PVP-I antimicrobial agents, a loading of 2.0 phr showed good antimicrobial efficacy with the largest zone of inhibition. Simultaneously, ZnO NP demonstrated excellent antimicrobial activity at low concentrations. The addition of antimicrobial agents shows a comparable effect on the mechanical properties of NR latex films. In comparison to control NR latex film (29.41 MPa, 48.49 N/mm), antimicrobial-filled films have significantly greater tensile and tear strengths (MPP (33.84 MPa, 65.21 N/mm), ZnO NP (31.79 MPa, 52.77 N/mm), and PVP-I (33.25 MPa, 50.75 N/mm). In conclusion, the addition of antimicrobial agents, particularly ZnO NP, can be a better choice for NR latex films because they will serve as both an activator and an antimicrobial. In a clinical context, with regard to frequently used medical equipment such as a stethoscope, such an approach offers significant promise to aid infection control.  相似文献   
25.
Chemotherapy-induced cognitive impairment (CICI) has emerged as a significant medical problem without therapeutic options. Using the platinum-based chemotherapy cisplatin to model CICI, we revealed robust elevations in the adenosine A2A receptor (A2AR) and its downstream effectors, cAMP and CREB, by cisplatin in the adult mouse hippocampus, a critical brain structure for learning and memory. Notably, A2AR inhibition by the Food and Drug Administration–approved A2AR antagonist KW-6002 prevented cisplatin-induced impairments in neural progenitor proliferation and dendrite morphogenesis of adult-born neurons, while improving memory and anxiety-like behavior, without affecting tumor growth or cisplatin’s antitumor activity. Collectively, our study identifies A2AR signaling as a key pathway that can be therapeutically targeted to prevent cisplatin-induced cognitive impairments.  相似文献   
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AIM: To compare the success, clinical outcomes, and maternal and neonatal complications between the Kiwi Omnicup and the Malmstrom metal cup in vacuum assisted delivery. METHODS: This was a prospective randomized comparative trial. Women who required vacuum assisted vaginal delivery were randomized into the Kiwi Omnicup (KO) group and the Malmstrom metal cup (MM) group. The vacuum assisted deliveries were conducted according to hospital protocol. Details of the procedure and delivery outcomes including success and complications were analyzed. RESULTS: One hundred and sixty-four women were recruited - 85 were assigned to vacuum assisted delivery using the KO and 79 the MM. One hundred percent delivery success was achieved with no significant differences between the two instruments in terms of maternal morbidity (P = 0.66). Six women in the MM group sustained post delivery complications in comparison to five in the KO group. Three babies were diagnosed with birth asphyxia in each group. More babies in the MM group were admitted to the Neonatal Intensive Care Unit (NICU) (10 babies versus 5 babies) and suffered complications (14 versus 12 babies), compared to the KO group, although the difference was not statistically significant. There were no intrapartum or neonatal deaths and of those admitted to the NICU, all were discharged within a week without any serious consequences. CONCLUSION: Kiwi Omnicup is an effective alternative to the currently available Malmstrom metal cup for vacuum assisted delivery with no increase in maternal or neonatal morbidity or mortality.  相似文献   
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We present a case of a 55-year-old woman presenting with worsening shortness of breath and constipation over the course of three days. Initial computed tomography scan showed a large, complex abdominal mass with a vascular pedicle and possible pedunculated origin along the inferior aspect of the greater curvature of the stomach. The mass was further evaluated on magnetic resonance imaging showing an active hemorrhage. The patient became hemodynamically unstable and general surgery was consulted for evaluation. Mass resection was performed, and biopsy revealed KIT/CD117+ and DOG1/ANO1+ gastrointestinal stromal tumor staged as T4. Although definitive diagnosis of a gastrointestinal stromal tumor requires biopsy, prompt clinical and radiological recognition is critical for patients to receive definitive treatment of mass resection.  相似文献   
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