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941.
We recorded visual neurons with the Elgiloy microelectrode in the frontal eye field of the alert monkey. After determining their visual receptive field, saccadic eye movements were induced by applying electric pulses at the recording site through the same electrode. The saccades were generally induced so as to bring the gaze angle to a part within the receptive field.  相似文献   
942.
943.
944.
胰十二指肠切除术(pancreaticoduodenectomy,PD)是治疗胰头癌、壶腹周围癌、十二指肠癌的主要术式。1935年Whipple首先施行PD手术成功,故大家又称PD为Whipple手术。Whipple手术的特点:复杂、费时、术后并发症多、死亡率高。而胰瘘是Whipple术后常见而严重的并发症,其发生率是15%~20%,它亦是术后引起腹腔感染、腹腔大出血等其它严重并发症的主要原因.同时也是术后早期致死的主要原因。  相似文献   
945.
BACKGROUND: The prognostic significance of the leukocyte subsets in peripheral blood has not yet been investigated in hepatocellular carcinoma patients. We sought to clarify the prognostic value of preoperative peripheral blood leukocyte subset counts, especially the absolute monocyte count, in HCC patients who have undergone hepatic resection. METHODS: We retrospectively examined the relation between the preoperative absolute number of peripheral monocytes and clinicopathologic factors or long-term prognosis in 198 patients with hepatocellular carcinoma who underwent curative resection. RESULTS: Univariate analysis indicated a significantly worse 5-year disease-free survival rate in patients with a peripheral blood monocyte count > 300/mm(3) (14.8%) than in patients with a count < or = 300/mm(3) (29.2%). There were no significant differences between patients in disease-free survival based on the lymphocyte or neutrophil count. According to multivariate analysis, preoperative peripheral blood monocyte count > 300/mm(3), alpha-fetoprotein level > 100 ng/mL, aspartate aminotransferase level > 100 IU/mL, and presence of microvascular invasion were independent risk factors for disease-free survival of less than 5 years. The peripheral blood monocyte count was higher in patients of male sex or those with a noncirrhotic liver, microvascular invasion, major hepatic resection, older age (>65 years), large tumor (> or =50 mm), or increased platelet count (>100,000/mm(3)) than in patients without these characteristics. CONCLUSIONS: Our findings indicate that the preoperative absolute count (>300/mm(3)) of peripheral blood monocytes may be related to tumor progression and that it is an independent risk factor for recurrence of hepatocellular carcinoma after resection. Postoperative adjuvant chemotherapy might be necessary in patients with elevation of the preoperative absolute count of peripheral blood monocytes.  相似文献   
946.
Elucidating the mechanism of liver tumor growth and metastasis after hepatic ischemia-reperfusion (I/R) injury of a small liver remnant will lay the foundation for the development of therapeutic strategies to target small liver remnant injury, and will reduce the likelihood of tumor recurrence after major hepatectomy or liver transplantation for liver cancer patients. In the current study, we aimed to investigate the effect of hepatic I/R injury of a small liver remnant on liver tumor development and metastases, and to explore the precise molecular mechanisms. A rat liver tumor model that underwent partial hepatic I/R injury with or without major hepatectomy was investigated. Liver tumor growth and metastases were compared among the groups with different surgical stress. An orthotopic liver tumor nude mice model was used to further confirm the invasiveness of the tumor cells from the above rat liver tumor model. Significant tumor growth and intrahepatic metastasis (5 of 6 vs. 0 of 6, P=0.015), and lung metastasis (5 of 6 vs. 0 of 6, P=0.015) were found in rats undergoing I/R and major hepatectomy compared with the control group, and was accompanied by upregulation of mRNA levels for Cdc42, ROCK (Rho kinase), and vascular endothelial growth factor, as well as activation of hepatic stellate cells. Most of the nude mice implanted with liver tumor from rats under I/R injury and major hepatectomy developed intrahepatic and lung metastases. In conclusion, hepatic I/R injury of a small liver remnant exacerbated liver tumor growth and metastasis by marked activation of cell adhesion, invasion, and angiogenesis pathways.  相似文献   
947.
948.
目的 评价不同镇静方法在小儿骶管麻醉术中镇静的优缺点 ,从而找到一种较为理想的镇静方法。方法 选择 45例ASAⅠ~Ⅱ级在骶管麻醉下行择期下腹部、会阴短小手术的患儿 ,体重 9~ 2 4kg。随机分为氟芬合剂对照组 (I)组、咪唑安定 (M )组和异丙酚 (P)组 ,每组 15例。I组 :氟芬合剂 (芬太尼 2 μg/kg) ;M组 :静脉泵注咪唑安定 1.5~ 2 .0 μg/kg·min ;P组 :静脉泵注异丙酚 2 5~ 75 μg/kg·min。每组患儿术中镇静评分在 2~ 4分。 结果 I组镇静效果比M组和P组差 (P <0 .0 5 ) ,呼吸抑制和术后躁动发生率较高。清醒时间I组比M组和P组延长 ,M组比P组延长 (P <0 .0 5 )。结论 持续静脉泵注异丙酚或咪唑安定是小儿骶管麻醉术中较为理想的镇静方法。  相似文献   
949.
A rare case of intraductal papillary mucinous tumor of the pancreas associated with a replaced common hepatic artery and celiac axis occlusion, which was treated by pancreatoduodenectomy, is reported. In this patient, the celiac trunk was occluded at its root and the splenic and left gastric artery could be visualized serially via the enlarged collateral artery on superior mesenteric arteriography. At surgery, the collateral artery was carefully preserved and pancreatoduodenectomy was successfully performed without ischemia of the stomach, spleen, and remnant pancreas. Although celiac axis occlusion is an uncommon finding for patients undergoing pancreatoduodenectomy, we recommend performing celio-mesenteric angiography before pancreatoduodenectomy, and, at surgery, clamping of the gastroduodenal artery is required for patients with celiac axis occlusion.  相似文献   
950.

Objective

This retrospective study aimed to determine the effect of simultaneous aortic valve replacement (AVR) and coronary artery bypass grafting (CABG) on operative outcomes and long-term survival in elderly patients with a high prevalence of comorbidity.

Methods

One hundred and fifty-seven elderly patients (70 years old or older) undergoing isolated AVR (n = 120) or combined AVR/CABG (n = 37) were evaluated. Operative outcomes were compared between the two surgical groups. Long-term survival was also compared between the groups using the Kaplan–Meier method and long-rank (Mantel–Cox) test.

Results

Operative mortality was 0.8 % for the isolated AVR group and 5.4 % for the combined AVR/CABG group (p = 0.076). The length of the intensive care unit stay for the combined AVR/CABG group was significantly longer than that for the isolated AVR group (median: 40 vs. 21 h, p = 0.008). However, the occurrence rate of hospital complications, such as reoperation for bleeding, deep sternal infection, supra-ventricular arrhythmia, and neurological complications, was similar between the two groups. Actuarial survival at 3 and 5 years was 82.3 and 80.9 % for the isolated AVR group, and 88.3 and 73.0 % for the combined AVR/CABG group, respectively (p = 0.637).

Conclusions

The satisfactory operative and long-term results in our study support a more aggressive simultaneous coronary revascularization combined with AVR for aortic valve stenosis in elderly patients.  相似文献   
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