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排序方式: 共有8312条查询结果,搜索用时 15 毫秒
1.
Philip S. Vendittelli Bassent Botros Howard S. Rosman Viren Govindaraju Anwar Zaitoun Tariq S. Marroush 《The American journal of the medical sciences》2019,357(4):333-337
Coronary embolism (CE) is an uncommon and unique cause of acute myocardial infarction. In this report, we review 216 cases of CE including 2 new cases from our institution. The mean patient age was 52.5 years and 62% of the patients were males. Chest pain was the most common presenting symptom followed by dyspnea, and the most commonly affected vessel was the left anterior descending artery. Leading etiologies of the embolus were atrial fibrillation, septic emboli, and iatrogenic causes. Treatment approaches varied with thrombus aspiration being used in 30% of cases. In-hospital mortality rate was 36% and 13% of the cases were complicated by cerebrovascular accident. CE is a unique pathology that leads to acute myocardial infarction. It portends a high mortality rate and requires a high level of suspicion as symptoms may be misleading. Further research is needed in order to improve recognition and management and to lower associated mortality. 相似文献
2.
去势后大鼠海马结构一氧化氮合酶阳性神经元的变化 总被引:8,自引:1,他引:7
目的:观察去势后大鼠海马结构一氧化氮合酶(NOS)阳性神经元的变化。方法:用黄递酶组织化学染色方法观察切除双侧卵巢后雌后SD大鼠海马结构NOS阳性神经元的形态,分布的变化,并进行计算机图像分析。结果:去势后海马结构NOS阳性神经元分布变化有区域差异性;NOS阳性神经元在下托、海马(CA)一区邻近下托的部分、CA三区、CA四区(CA4)和齿状回(DG)数目明显减少,而在CA二区数目明显明显增多,CA4和DG的NOS阳性神经元平均密度降低,胞体的平均周长和平均截面积都明显减少。结论:雌激素可能通过影响海马结构NOS的表达来影响学习和记忆。 相似文献
3.
The formation of the blood-testis barrier (BTB) in the domestic fowl was studied at the electronmicroscopic level employing lanthanum as a tracer. No effective barrier could be demonstrated in testes before puberty, although several components of the Sertoli junctional complex such as focal tight junctions and desmosomes were already existent. The time of onset of meiosis after hatching showed great individual variation and meiosis did not occur synchronously in the tubules of a given testis. An effective barrier could first be detected in tubules containing early spermatids, and in which spermatogonia and primary spermatocytes at the leptotene stage were still within the open compartment. Thus, barrier formation was correlated with the occurrence of haploid germ cells. Complete compartmentation of seminiferous tubules, leaving only spermatogonia within the open compartment, was attained in tubules containing elongated spermatids of the maturation phase. In these tubules, primary spermatocytes at the leptotene stage were situated in an intermediate compartment. 相似文献
4.
目的 探讨肝细胞癌(HCC)合并胆管癌栓患者术中癌栓的处理方式和术后恢复过程。方法 对1995年1月-2002年12月手术治疗的27例HCC合并胆管癌栓情况进行回顾性总结和分析。结果 只有59.3%(16/27)患者行肝切除、胆管取癌栓及胆管引流术。全组术后并发症发生率为55.6%(15/27),术后30d病死率为22.2%(6/27)。结论 HCC合并胆管癌栓的预后差,早期诊断和外科手术治疗是改善此病预后的关键。 相似文献
5.
Central axons of sensory ganglion (SG) neurons of the Xenopus tail enter the spinal cord via the ventral roots and travel dorsally and rostrally following a diagonal course within the lateral marginal zone (LMZ) to reach the dorsolateral fasciculus (DLF) (Nordlander et al.: Brain Res., 440:391-395, 1988). Axons are dispersed as they cross the cord. At the DLF they turn and travel together rostrally, sharing the fascicle with axons of primary sensory neurons (Rohon-Beard cells) already present in the tract. In this paper we analyze the growth patterns of the central projections of SG axons in the tail by using HRP applied to proximal branches of tail spinal nerves. Growth cones of the diagonal route are variable in configuration, often bearing processes that spread within the LMZ. Once the DLF, growth cones change shape, becoming distinctly linear. While growth cones navigating the diagonal part of the route never contact or fasciculate with other diagonal SG axons, SG growth cones and axons of the DLF are more closely associated with their fellows. Measurements of the slopes of SG axons in the diagonal route indicated a limited range with a mean of 23 degrees with respect to the cord axis. On the basis of these observations, we conclude that 1) navigational patterns for growth cones of this pathway differ for the diagonal versus the DLF part of its course, and 2) fasciculation is not a mechanism used by SG axons to reach the DLF, but that instead, each axon is able to find its way independently. 相似文献
6.
Angular bundle kindling is accelerated in rats with a genetic predisposition to acoustic stimulus-induced seizures 总被引:5,自引:0,他引:5
Limbic kindling was examined in genetically epilepsy-prone (GEPR) and non-epileptic control rats. The early stage of kindling development was accelerated in both groups of GEPR rats compared to controls. Later stages of kindling were accelerated in GEPR-9 but not GEPR-3 rats. These results indicate that GEPR rats have an enhanced susceptibility to limbic kindling and suggest that limbic brain alterations may contribute to acceleration of the early stage kindling development in GEPR rats. 相似文献
7.
目的 研究h-BMP-2基因转染骨髓间充质干细胞(BMSCs)在复合煅烧骨、β-TCP或直接植入裸鼠股部后的成骨能力。方法 通过影像学、组织学和形态计量学等方法,观察未经诱导、OS液诱导和h-BMP-2基因转染BMSCs在复合煅烧骨,或多孔β-TCP后植入裸鼠皮下,或直接制成细胞悬液注入,在4、8、12周诱导成骨和材料降解情况。结果 在裸鼠皮下,单纯生物陶瓷不能诱导成骨,而复合了未诱导、OS液诱导和h-BMP-2基因转染BMSCs的生物陶瓷均能成骨,成骨量为h-BMP-2基因转染组>OS液诱导组>未经诱导组(P<0.05),B-TCP可随骨长入而降解;注入裸鼠肌肉的OS液诱导的和h-BMP-2转染的BMSCs均能诱导成骨,而未经诱导MSCs则不能成骨。结论 复合人BMP基因转染BMSCs的β-TCP是一种理想的骨修复材料。 相似文献
8.
Ung-il Chung Hiroshi Kawaguchi Tsuyoshi Takato Kozo Nakamura 《Journal of orthopaedic science》2004,9(4):410-414
Mammalian bones have three distinct origins (paraxial mesoderm, lateral plate mesoderm, and neural crest) and undergo two different modes of formation (intra-membranous and endochondral). Bones derived from the paraxial mesoderm and lateral plate mesoderm mainly form through the endochondral process. During this process, hypertrophic chondrocytes play a vital role in inducing both osteogenesis and angiogenesis. One of the essential osteogenic factors secreted from hypertrophic chondrocytes is Indian hedgehog (Ihh). In contrast, bones derived from the neural crest mainly form through the intramembranous pro-cess and do not require Ihh. Thus, depending on their origin, bones have distinct signaling properties, which need to be considered in the research and application of bone biology.Presented at the 18th Annual Research Meeting of the Japanese Orthopaedic Association, Kitakyushu, Japan, October 17, 2003 相似文献
9.
Clinical outcome of surgical management for patients with renal cell carcinoma involving the inferior vena cava 总被引:1,自引:0,他引:1
Tomoaki Terakawa Hideaki Miyake Atsushi Takenaka Isao Hara Masato Fujisawa 《International journal of urology》2007,14(9):781-784
BACKGROUND: The objective of this study was to evaluate the clinical outcome after surgical management of renal cell carcinoma (RCC) extending to the inferior vena cava (IVC). METHODS: This study included a total of 55 patients (41 men and 14 women; mean age, 59.3 years) with RCC (39 right- and 16 left-sided tumors) involving the IVC, who underwent radical nephrectomy and tumor thrombectomy between 1983 and 2005 at a single institution in Japan. The level of thrombus was classified as follows: level I, infrahepatic; level II, intrahepatic; level III, suprahepatic; and level IV, extending to the atrium. Clinicopathological data from these patients were retrospectively reviewed to identify factors associated with survival. RESULTS: There were 11 and 18 patients who were diagnosed as having lymph node and distant metastases, respectively. Twenty-two patients had tumor thrombus in level I, 20 in level II, 10 in level III, and 3 in level IV. Pathological examinations demonstrated that 34 and 21 patients had clear cell carcinoma and non-clear cell carcinoma, respectively, 42, 9 and 4 were pT3b, pT3c and pT4, respectively, and 6, 35 and 14 were Grades 1, 2 and 3, respectively. Cancer-specific 1-, 3- and 5-year survival rates of these 55 patients were 74.5%, 51.4% and 30.3%, respectively. Among several factors examined, clinical stage (P = 0.047), lymph node metastasis (P = 0.016), histological subtype (P = 0.034) and tumor grade (P < 0.001) were significantly associated with cancer-specific survival by univariate analysis. Furthermore, multivariate analysis demonstrated clinical stage (P = 0.037) and tumor grade (P < 0.001) as independent predictors of cancer-specific survival irrespective of other significant factors identified by univariate analysis. CONCLUSIONS: In patients with RCC involving the IVC, biological aggressiveness characterized by tumor grade rather than tumor extension would have more potential prognostic importance; therefore, more intensive multimodal therapy should be considered in patients with high grade RCC with tumor thrombus extending into the IVC. 相似文献
10.
Testicular cancer with tumor thrombus extending to the inferior vena cava successfully removed using veno-venous bypass: A case report 总被引:1,自引:0,他引:1
Yoshiaki Kinebuchi Teruyuki Ogawa Haruaki Kato Yasuhiko Igawa Osamu Nishizawa Shin-Ichi Miyagawa 《International journal of urology》2007,14(5):458-460
A 33-year-old man with a left testicular tumor was referred to Shinshu University Hospital for advanced therapy. Radiographic imaging revealed multiple metastases in the retroperitoneal lymph nodes (RPLN) and bilateral lungs, as well as tumor thrombus that extended from the left renal vein to the inferior vena cava (IVC) adjacent to the right atrium. After orchidectomy, a diagnosis of embryonal carcinoma was made with a clinical stage of T1N2M1bS3, which has a poor prognosis, based on the International Germ Cell Cancer Collaborative Group consensus. After eight courses of chemotherapy, the patient's tumor markers normalized and the lung metastases disappeared, but the RPLN and tumor thrombus remained. Retroperitoneal lymph node dissection and thrombectomy were performed using a veno-venous bypass (VVB). The pathological examination of the thrombus revealed a mature teratoma. The patient has been disease-free since surgery. 相似文献