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971.
Mousumi Rahman Qazi Zhenlei Xia Jasna Bogdanska Shu-Ching Chang Dave J. Ehresman John L. Butenhoff B. Dean Nelson Joseph W. DePierre Manuchehr Abedi-Valugerdi 《Toxicology》2009,260(1-3):68-76
We have previously shown that short-term, high-dose exposure of mice to the environmentally persistent perfluorooctanoate (PFOA) results in thymic and splenic atrophy and the attenuation of specific humoral immune responses. Here we characterize the effects of a 10-day treatment with different dietary doses (1–0.001%, w/w) of perfluorooctanesulfonate (PFOS), a similar fluorochemical, on the immune system of male C57BL/6 mice. At doses greater than 0.02%, PFOS induced clinical signs of toxicity in the animals, whereas at the concentration of 0.02%, this compound caused weight loss, hepatomegaly and atrophy of the thymus, spleen and adipose tissue without toxicity. With this latter dose, histopathological and flow-cytometric analysis revealed that (i) the thymic cortex was virtually depleted of cells; (ii) the total numbers of thymocytes and splenocytes were reduced by 84 and 43%, respectively; (iii) although all populations of thymocytes and splenocytes were smaller, the thymic CD4+CD8+ cells and the splenic B-lymphocytes were most decreased. These alterations resembled those evoked by analogous exposure to PFOA, but were less pronounced. At lower doses (less than 0.02%), PFOS induced hepatomegaly without affecting the thymus or spleen. Finally, comparison of male wild-type 129/Sv mice and the corresponding knock-outs lacking peroxisome proliferator-activated receptor-alpha (PPARα) indicated that these effects of PFOS are not strain-dependent. More importantly, hepatomegaly is independent of PPARα, the thymic changes are partially dependent on this receptor, and splenic responses are largely eliminated in its absence. Thus, immunomodulation caused by PFOS is a high-dose phenomenon partially dependent on PPARα. 相似文献
972.
目的探讨影响贲门癌切除术后长期生活的因素。方法对584例贲门癌切除术后生存10年以上的病例进行回顾性分析。结果本组10年生存率为17.1%。肿瘤的病理分期、分化程度、大体类型、瘤体大小对10年生存率的影响均有统计学意义(P〈0.05)。有无淋巴结转移对10年生存率的影响有统计学意义(P〈0.01)。伴有切端癌残留、癌栓形成、肿瘤浸润浆膜、手术切除性质,以及性别、年龄、病程等对10年生存率影响无统计学意义(P〉0.05)。结论贲门癌的早期发现、早期诊断、早期切除治疗仍是提高其10年生存率的关键。切端癌残留、癌栓形成、手术切除性质等因素对10年生存率的影响尚待进一步探讨。 相似文献
973.
原发性脾脏肿瘤25例临床分析 总被引:1,自引:0,他引:1
目的探讨原发性脾脏肿瘤的诊断和治疗。方法对我院25例原发性脾脏肿瘤患者的临床资料进行回顾性分析。结果本组除4例失访外,其余21例术后随访15个月~4年。其中良性肿瘤患者随访7例均存活;恶性肿瘤患者随访14例,生存期〈1年5例,生存期1~3年6例,生存期〉3年3例。结论B超、CT等检查是诊断原发性脾脏肿瘤的主要手段,治疗方法首选手术。 相似文献
974.
Entirely laparoscopic radical gastrectomy for adenocarcinoma: lymph node yield and resection margins
Sarela AI 《Surgical endoscopy》2009,23(1):153-160
Background Laparoscopic assisted distal gastrectomy for adenocarcinoma has been widely reported from Japan and Korea but there are sparse
data for Western patients. This study aimed to describe and compare the perioperative outcomes and pathological staging for
consecutive patients who underwent laparoscopic or open gastrectomy by a single surgeon in the UK.
Methods During the period from April 2005 to May, 2007, patients with gastric adenocarcinoma were selected for open or laparoscopic
resection at the discretion of the surgeon. Gastric resections for gastrointestinal stromal tumour (GIST) or benign disease
were excluded. Laparoscopic gastrectomy was performed entirely laparoscopically with intracorporeal anastomosis, followed
by specimen retrieval via a suprapubic incision.
Results There were 21 men and 8 women, median age 75 years (range 45–88 years), with American Anaesthesiology Association scores of
3 or 4 in 19 patients. Gastrectomy was performed laparoscopically in 18 patients (62%; total gastrectomy, 6 patients) or open
in 11 patients (total gastrectomy, 7). Five laparoscopic gastrectomies were converted to open procedures, three patients had
re-laparoscopy and one patient had subsequent laparotomy. As compared with open gastrectomy, laparoscopic resection had longer
operation time and similar length of hospital stay. There was one postoperative mortality in each group. There was similar
lymph node retrieval for laparoscopic or open resection [23 (range 10–44) versus 26 (8–95), respectively; p = 0.40], with inadequate lymphadenectomy (<15 nodes) in two laparoscopic cases and one open case. R1 resection was limited
to patients with pT3 disease (laparoscopic, 4; open, 2).
Conclusions Perioperative outcomes were similar for laparoscopic or open gastrectomy. Lymphadenectomy was adequate in 89% of laparoscopic
gastrectomies. pT3 tumours were at risk of noncurative resection, as described in large Western series of open gastrectomy. 相似文献
975.
Central nervous system administration of interleukin-6 produces splenic sympathoexcitation 总被引:1,自引:0,他引:1
Helwig BG Craig RA Fels RJ Blecha F Kenney MJ 《Autonomic neuroscience : basic & clinical》2008,141(1-2):104-111
Interleukin-6 (IL-6) is a multifunctional cytokine that has been shown to play a pivotal role in centrally-mediated physiological responses including activation of the hypothalamic-pituitary-adrenal axis. Cerebral spinal fluid (CSF) concentrations of IL-6 are elevated in multiple pathophysiological conditions including Alzheimer's disease, autoimmune disease, and meningitis. Despite this, the effect of IL-6 on central regulation of sympathetic nerve discharge (SND) remains unknown which limits understanding of sympathetic-immune interactions in health and disease. In the present study we determined the effect of intracerebroventricular (i.c.v, lateral ventricle) administration of IL-6 on splenic SND in urethane-chloralose-anesthetized rats. A second goal was to determine if icv injected IL-6 enters the brain parenchyma and acts as a volume transmission signal to access areas of the brain involved in regulation of sympathetic nerve outflow. i.c.v administration of IL-6 (10 ng, 100 ng, and 400 ng) significantly and progressively increased splenic SND from control levels in baroreceptor-denervated Sprague-Dawley rats. Administration of 100-ng and 400-ng IL-6 resulted in significantly higher SND responses when compared to those elicited with a 10-ng dose. Sixty minutes following icv administration, fluorescently labeled IL-6 was not distributed throughout the parenchyma of the brain but was localized to the periventricular areas of the ventricular system. Brain sections counter-stained for the IL-6 receptor (IL-6R) revealed that IL-6 and the IL-6R were co-localized in periventricular areas adjoining the third ventricle. These results demonstrate that icv IL-6 administration increases splenic SND, an effect likely achieved via signaling mechanisms originating in the periventricular cells. 相似文献
976.
While graft rejection has been studied for many years, recent investigations have focused on the generation and maintenance of transplantation tolerance. This review examines the role of secondary lymphoid organs, especially the spleen, characterizes the maintenance mechanism that is key to the development of tolerance and explores the implications of new strategies for inducing tolerance in transplantation. 相似文献
977.
Yeo W Boyer M Chung HC Ong SY Lim R Zee B Ma B Lam KC Mo FK Ng EK Ho R Clarke S Roh JK Beale P Rha SY Jeung HC Soo R Goh BC Chan AT;Cancer Therapeutics Research Group 《Cancer chemotherapy and pharmacology》2007,59(3):295-300
Background The purpose of this study was to evaluate the tolerability and efficacy of irofulven, a DNA interacting acylfulvene analog,
as first line therapy for patients with recurrent or metastatic gastric cancer.
Patients and methods Twenty-three patients with recurrent or metastatic gastric cancer received irofulven at a dose of 0.45 mg/kg administered
intravenously over 30-min infusion (up to a maximum of 50 mg), on days 1 and 8, every 3 weeks.
Results The median number of cycles delivered per patient was 2 (range 1–6). Two patients (9%) had ≥ 1-week delay in administration
of subsequent cycle of chemotherapy. For the day 8 chemotherapy, dose reductions were required in seven patients (30%); dose
omitting occurred in five patients (22%). Grade 3/4 anemia and neutropenia occurred in 22 and 17% of patients, respectively.
There was no grade 4 thrombocytopenia and no neutropenic fever was observed. Of the 20 evaluable patients, there were no responses
observed, 3 patients had stable disease after 2 cycles of treatment which was not confirmed by a further assessment. Median
overall survival was 6.05 months (95% CI 4.55–9.39).
Conclusions Irofulven was tolerated at the dose of 0.45 mg/kg on days 1 and 8, every 3 weeks but showed no evidence of antitumor activity
in patients with advanced gastric cancer. 相似文献
978.
979.
Lee MW Kim SH Kim YJ Lee JM Lee JY Park EA Choi JY Han JK Yang HK Lee HJ Choi BI 《Abdominal imaging》2008,33(3):255-261
Background To determine whether CT gastrography can be used as a comprehensive imaging modality for the evaluation of gastrointestinal
stromal tumor (GIST) of the stomach.
Methods Thirty patients with gastric GISTs were included. Using CT gastrography, two radiologists determined the morphology, location,
size of the tumor, and the nearest distance from the tumor to the gastroesophageal junction or pylorus in consensus. The ability
of 3D CT gastrography in dealing with surface-shaded/transparent images and virtual endoscopic images was also evaluated and
compared with the results of barium study and gastroscopy, respectively.
Results In regard to lesion morphology and location, almost perfect agreements (κ = 0.87 ∼ 1.00) were achieved between CT gastrography and surgery, and the difference in lesion size between CT and surgery
was not statistically significant (P = 0.824). In terms of the distance from the tumor to the gastroesophageal junction or pylorus, a statistically significant
difference was found between the laparoscopic and open gastric surgery groups (P < 0.001). Findings on CT gastrography were mostly similar or superior to those seen on barium study and gastroscopy.
Conclusions CT gastrography can serve as a comprehensive imaging test for the preoperative evaluation of gastric GIST. 相似文献
980.