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81.
Introduction Delayed massive hemorrhage induced by pancreatic fistula after pancreaticoduodenectomy is a rare but life-threatening complication. The purpose of this study was to analyze the clinical course of patients with late hemorrhage, with or without sentinel bleeding, to better define treatment options in the future. Material and Methods From April 1998 to December 2006, 189 pancreaticoduodenectomies were performed. Eleven patients, including two patients referred from other hospitals, were treated with delayed massive hemorrhage occurring 5 days or more after pancreaticoduodenectomy. Sentinel bleeding was defined as minor blood loss via surgical drains or the gastrointestinal tract with an asymptomatic interval until development of hemorrhagic shock. The clinical data of patients with bleeding episodes were analyzed retrospectively. Results Eight of the 11 patients had sentinel bleeding, and seven of them had it at least 6 h before acute deterioration. Seven out of 11 patients died, five out of eight with sentinel bleeding. No differences could be detected between patients with or without sentinel bleeding before delayed massive hemorrhage. The only difference found was that non-surviving patients were significantly older than surviving patients. Delayed massive hemorrhage is a common cause of death after pancreaticoduodenostomy complicated by pancreatic fistula formation. The observation of sentinel bleeding should lead to emergency angiography and dependent from the result to emergency relaparotomy to increase the likelihood of survival.  相似文献   
82.
目的 探讨伴淋巴结鳞状细胞癌转移的梭形细胞肌上皮癌病理特征、诊断和鉴别诊断,提高对该肿瘤的诊断水平.方法 对1例颌下腺梭形细胞肌上皮癌及颈清扫淋巴结进行组织形态学和免疫组化观察,并结合文献复习.结果 肿瘤主要由梭形细胞构成,细胞排列紧密,异型性明显,分裂相易见伴大片坏死及玻璃样变.经广泛取材,见到少许小管样结构及小灶状鳞状细胞癌成分.颈清扫淋巴结可见鳞状细胞癌转移.免疫组化显示,梭形肿瘤细胞:SMA、Desmin灶状阳性,p53强阳性,CK(AE1/AE3)、S-100、CD34、GFAP、CD10、HMB45均为阴性;淋巴结转移癌成分CK(AE1/AE3)阳性、SMA阴性.结论 肌上皮癌属于罕见的恶性肿瘤,梭形细胞为主的肌上皮癌,其淋巴结转移癌的形态可以与肿瘤主体细胞的形态截然不同.根据组织学特点,结合免疫组化及电镜观察,可以作出明确诊断及鉴别诊断.  相似文献   
83.
术中淋巴染色对早期乳腺癌前哨淋巴结判定作用的研究   总被引:3,自引:1,他引:2  
目的:探讨术中淋巴染色在早期乳腺癌前哨淋巴结判定中的作用。方法:62例Ⅰ、Ⅱ期乳腺癌,术中向乳腺肿块或其周围组织内注入1%亚甲蓝注射液4ml,术后将腋淋巴结按部位统计每例染色淋巴结的数量、转移度,计算用染色淋巴结判断腋淋巴结转移情况的敏感性、特异性、准确性和漏诊率。结果:62例淋巴染色均而获成功。23例腋淋巴结查见转移癌,其中20例染色淋巴结查见转移癌。判断腋淋巴结有无转移敏感性为87.0%(20/23),特异性为100%(39/39),准确性为93.7%(59/62),漏诊率为13.0%。染色淋巴结的转移度34.8%(39/112),与总体淋巴结及未染色淋巴结的转移度(27.5%、29.7%)差异没有统计学意义。结论:采用亚甲蓝作为术中淋巴染色剂,对早期乳腺癌病人有较高的成功率,应用染色淋巴结作为前哨淋巴结来判断腋淋巴结转移情况有较高的漏诊率,其应用价值尚待进一步大样本的研究评价。  相似文献   
84.
目的:讨论急性下壁心肌梗死患者缓慢性窦房结功能紊乱的发生率。临床意义及转归。方法:对260例急性下壁心肌梗死患者的临床状况及心电图进行连续观察分析。结果:发生缓慢性窦房结功能紊乱者共50例。其中窦性心动过缓36例(13.85%,36/260),窦房阻滞8例(3.08%,8/260)。窦性静止6例(2.31%,6/260)。结论:急性下壁心肌梗死患者缓慢性窦房结功能紊乱发生率较高,且多标志病情较严重。  相似文献   
85.
Pacemaker Current if. Since the hyperpolarization-activated current, if, was originally associated with the diastolic depolarization phase of action potential in the sinoatrial (SA) node in 1979, its central role in the generation and control of pacemaker activity has become increasingly clear through a series of experimental findings, some of which have substantially modified the pre-existing theories of cardiac pacemaking and its modulation by the autonomic transmitters. Thus, the pacemaker current of Purkinje fibers, formerly described as a deactivating pure potassium (K) current, was found to be in fact, like the nodal if, inward and activating on hyperpolarization. Furthermore, in SA node cells, as well as mediating rhythm acceleration induced by catecholamines, if was found to underlie the slowing effect of low acetylcholine (ACh) concentrations, in contrast with the generally accepted hypothesis that activation of a K conductance is the main process responsible for cardiac slowing. A final, atypical property of if recently demonstrated concerns the activating action exerted on if by intracellular cAMP. Unlike that on other voltage-gated, cAMP-modulated cardiac channels, this action is independent of phosphorylation and involves a direct binding of cAMP to if channels. (J Cardiovasc Electrophysiol, Vol. 3, pp. 334–344, August 1992)  相似文献   
86.
The aim of the study was to evaluate whether complication rate, costs, operation times, and hospitalization times differed in two different patient groups: in group 1, frozen section analysis of the sentinel lymph node and lymph node dissection were carried out in the same operation. In group 2, normal investigation of the sentinel lymph node and lymph node dissection were done in a second operation. One hundred thirty-five patients with cutaneous melanoma were included. Hospitalization times, costs, complication rates, and operation times of two-stage and one-stage lymph node dissection of the draining area after detection of metastases in the sentinel lymph node were retrospectively compared. Lymph node metastasis in the sentinel lymph node was found in 23 patients. In 11 patients, removal of the sentinel lymph node and dissection of the lymph node basin was performed in the same operation. In 12 patients, a two-stage procedure was the treatment of choice. Operation times were not different in the two groups (p=0.87) while two-stage operation patients were hospitalized significantly longer (14.2 ± 9.7 vs 23.9 ± 24 days; p=0.01) and costs were significantly higher (7,836.90 ± 2,397.95 Swiss francs vs 5,279.40 ± 1,994.90 Swiss francs). In addition, more complications were found in the two-stage group.  相似文献   
87.
保留神经腹膜后淋巴结清除术治疗睾丸肿瘤   总被引:1,自引:0,他引:1  
目的探讨保留神经腹膜后淋巴结清除术(RPLND)在低期睾丸肿瘤治疗中的作用和效果。方法1999年6月至2003年7月收治睾丸肿瘤患者13例,年龄24~41岁,平均29岁。肿瘤位于左侧9例,右侧4例,大小2cm×3cm×2cm~9cm×6cm×5cm。临床分期:Ⅰ期11例,均为非精原细胞瘤;ⅡA期1例,为畸胎瘤(CT示腹膜后转移灶1cm×2cm);ⅡC期1例,为精原细胞瘤(CT示腹膜后转移灶10cm×9cm)。12例非精原细胞瘤者根治性睾丸切除术后1~4周行保留神经RPLND,1例精原细胞瘤者根治性睾丸切除术后行3疗程BEP方案化疗后行保留神经RPLND。结果术后病理分期:Ⅰ期11例,ⅡA期2例,其中ⅡC期精原细胞瘤患者化疗后分期降为Ⅰ期。13例术后均无肠梗阻、淋巴瘘和体位性低血压。术后2周复查时血AFP和βHCG均降至正常范围。术后8~12周均恢复射精功能。随访18~64个月,平均39个月,无肿瘤复发或转移。结论对于青壮年患者,保留神经RPLND是治疗低期非精原细胞瘤和化疗后降期的精原细胞瘤的首选方法。  相似文献   
88.
作者对结节性甲状腺肿及其非典型结节与甲状腺癌细胞核直径、面积及 DNA 含量检测,发现核直径与面积的(?)和 S 为甲状腺癌组>非典型结节组>对照组(P<0.01);随着细胞增生异型程度的加重,核直径、面积及离散程度随之增加、DNA 含量也显著增加,显示Ⅲ级 DNA 含量细胞出现频率越高恶性的可能性就越大;同时发现各组细胞核不同 DNA 含量的核直径、面积均明显增加,与对照组相比差异生非常显著(P<0.01)。  相似文献   
89.
Recent advances in molecular lymphology and lymphatic phenotyping techniques in small animals offer new opportunities to delineate mutant mouse models. Chy-3 mutant mice were originally named for their chylous ascites, but the underlying lymphatic disorder was not defined. We now re-examined these mice and applied advanced genotyping and lymphatic phenotyping techniques to pinpoint the specific lymphatic defect in this mouse model. We demonstrated that Chy-3 mice carry a large chromosomal deletion that includes Vegfc and narrowed this region by monitoring the heterozygosity of genetic markers. We found that Chy-3 mice not only exhibited chylous ascites but also lymphedema of the hind paws and, in approximately half of the males, lymphedema of the penis. Visual lymphangiography and immunofluorescence staining showed a hypoplastic dermal lymphatic network, whereas the blood vasculature appeared unaffected. This hypoplastic lymphatic network was functional, and all adult Chy-3 mice exhibited a lateral lymphatic pathway directly connecting the inguinal to the axillary lymph node. The dermal superficial to deep lymphatic connections in upper limbs and in all cervical regions were intact and functionally drained the upper body. Lymphatic tracer was not transported from the dermal to the deep truncal lymphatic system in the lower limbs, even though the deep lymphatic vessels and nodes were present and patent. These findings further delineate the lymphatic phenotype of Chy-3 mice, identify a collateral lymph drainage pathway previously undescribed in other genetic models of lymphedema, and demonstrate a predilection for lymphatic abnormalities of the lower limbs.  相似文献   
90.
高频彩超对颈部淋巴结囊性病变的诊断价值   总被引:2,自引:2,他引:0  
①目的探讨高频彩超对颈部淋巴结囊性病变的诊断价值。②方法回顾性分析25例颈部淋巴结囊性病变的高频彩超表现。③结果颈部淋巴结囊性病变见于颈淋巴结囊性转移瘤、化脓性淋巴结炎及淋巴结结核。其中13例为颈部淋巴结囊性转移瘤,其特征性超声表现为颈部淋巴结囊性肿大,伴囊壁实性结节;较大囊壁结节内常可探及动脉血流信号,部分囊壁结节可见微钙化。7例为颈部急性化脓性淋巴结炎,其主要超声表现为上颈部淋巴结呈单发、圆形囊性肿大;囊壁略厚,且较均匀;囊液呈细密点状回声。5例为颈部淋巴结干酪脓肿型结核,其主要超声表现为单侧或双侧中下颈部淋巴结呈多发、椭圆形囊性肿大,部分可融合成团;内壁毛糙,囊液内散在分布点状高回声。④结论高频彩超检查对颈部淋巴结囊性病变的诊断和鉴别诊断具有重要价值。  相似文献   
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