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71.
72.
K Gohji H Yasuno O Matsumoto S Kamidono A Itani G Hamami S Morishita C Yamashita M Okada K Nakamura 《Nippon Gan Chiryo Gakkai shi》1989,24(6):1266-1276
We performed clinical analysis of 12 patients with renal cell carcinomas associated with tumor thrombosis in the inferior vena cava. Eleven cases were men, and one was a woman; their ages range from 48 to 76 years old with a mean of 58 years. Nine tumors were observed on the right side, the other 3 tumors were observed on the left side. In five cases, the distant metastases of the disease were noticed at the first visiting to our hospital. Lung metastases were found in five and bone or liver in each one. Chief complaints were macroscopic hematuria in 8 cases (67%), and were weight loss or general fatigue. The symptoms of obstruction of the inferior vena cava, such as venous dilatation of abdominal wall, edema of lower extremities and varicocele of the testes, were seen in 6 cases. The level of the tumor thrombosis was preoperatively determined by CT, echography, cavography or MRI. The level was near the right atrium in one, near the hepatic vein in 8 and near the renal vein in 3, although there was no case extending into the right atrium. Transperitoneal nephrectomy and thrombectomy in the inferior vena cava were performed in 9 cases. Surgery could not be performed in the other 3 patients of their poor general condition or severe heart disease. One patient died because of massive hemorrhage during the operation. The other complications were transient renal failure in 3 cases and postoperative bleeding in one case. In 4 patients without distant metastases or regional lymph nodes metastasis, two died of multiple metastasis of renal cell carcinomas and diabetic coma. The other two cases are alive without disease for 4 and 40 months after operation. For renal cell carcinoma extending into the inferior vena cava without metastasis, nephrectomy and thrombectomy should be performed using the extracorporeal circulation. 相似文献
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75.
The Plk3-Cdc25 circuit 总被引:3,自引:0,他引:3
Polo-like kinases (Plks) are key regulators of the cell cycle, especially in the G2 phase and mitosis. They are incorporated into signaling networks that regulate many aspects of the cell cycle, including but not limited to centrosome maturation and separation, mitotic entry, chromosome segregation, mitotic exit, and cytokinesis. The Plks have well conserved 30-amino-acid elements, designated polo boxes (PBs), located in their carboxyl-termini, which with their flanking regions constitute a functional Polo-box domain (PBD). Members of the Plk family exist in a variety of organisms including Polo in Drosophila melanogaster; Cdc5 in Saccharomyces cerevisiae; Plo1 in Schizosaccharomyces pombe; Plx1 in Xenopus laevis; and Plk1, Snk/Plk2, Fnk/Prk/Plk3, and Sak in mammals. Polo, Cdc5, and Plo1 are essential for viability. The Plks can be separated into two groups according to their functions. The first group (Polo, Cdc5, plo1, Plx1, and Plk1) primarily performs mitotic functions, whereas the second group (Plk2 and Plk3) appears to have additional functions during the G1, S, and G2 phases of the cell cycle. Several contributions to this issue will discuss different aspects of Plk involvement in cell-cycle regulation. This review, therefore, will focus on the role of Plk3 in regulating Cdc25 phosphatase function and its effect on the cell cycle. 相似文献
76.
Nakamura F Fujioka M Takahashi KA Ueshima K Arai Y Imahori Y Itani K Nishimura T Kubo T 《Annals of nuclear medicine》2005,19(7):549-555
OBJECTIVE: Non-traumatic osteonecrosis of the femoral head (ONF) is considered to be a disease that occurs primarily due to ischemia of the femoral head, while its etiology and pathology are not fully understood. It is therefore necessary to identify the characteristics of the hemodynamics of the femoral head. In this study, the hemodynamics in the ilium and proximal regions of the femur, including the femoral head, was investigated using positron emission tomography (PET). METHODS: The subjects of this study consisted of 8 hip joints of four healthy male adults and 3 hip joints on the contralateral side of a femoral neck fracture, avulsion fracture of the greater trochanter and coxarthrosis (1 case each, all females) for a total of 11 hip joints of 7 subjects. The ages of the subjects ranged from 25 to 87 years (average age: 54 years). Blood flow was measured by means of the H215O dynamic study method and blood volume was measured by means of the 15O-labeled carbon monoxide bolus inhalation method. RESULTS: Blood flow was determined to be 9.1 +/- 4.8 ml/min/100 g in the ilium and among proximal regions of the femur (femoral head, neck and intertrochanteric region), 1.8 +/- 0.7 ml/min/100 g in the femoral head, 2.1 +/- 0.6 ml/min/100 g in the femoral neck, and 2.6 +/- 0.7 ml/min/100 g in the intertrochanteric region. In addition, blood volume was 4.7 +/- 1.3 ml/100 g in the ilium, and among proximal regions of the femur, 1.1 +/- 0.5 ml/100 g in the femoral head, 2.1 +/- 0.7 ml/100 g in the femoral neck, and 2.6 +/- 0.9 ml/100 g in the intertrochanteric region. The results showed that both blood flow and volume were lowest in the femoral head. Blood flow and volume were significantly lower in the proximal regions of the femur (femoral head, neck and intertrochanteric region) than in the ilium (p < 0.01). CONCLUSION: The present study demonstrated that the femoral head is in a hypoemic state as compared with other osseous tissue, indicating that even the slightest exacerbation of hemodynamics in the femoral head can trigger an ischemic condition culminating in ONF. 相似文献
77.
BACKGROUND: Traditionally, development of physician leadership has occurred at random in surgical training. One possible reason is that surgical educators have focused on detailed instruction on critical patient situations, resuscitation, and technical skills, but they have provided little formal training in the essential leadership skills. METHODS: To determine resident perceptions about the importance of these skills and individual strengths and weaknesses in these areas, a questionnaire was administered to 43 residents in our general surgery program. In part one of the questionnaire, the residents ranked 18 leadership skills on a scale of 1 to 4 in importance ("not important," "minimally important," "somewhat important," and "very important") for career development. The second portion of the questionnaire asked the residents to rate themselves on a similar scale with regard to their personal confidence and competence in these same areas. RESULTS: Twenty-three residents (53%) completed the entire questionnaire. The majority of the residents (92%) rated all 18 leadership skills "somewhat" or "very important" for career development. More than 50% of the residents rated themselves as not competent or minimally competent in 10 of the 18 areas. Ethics was the only area in which >75% of the residents believed themselves to be more than minimally competent. There were no significant differences between postgraduate training levels in any of the parameters calculated. CONCLUSIONS: We conclude that although residents see these nontraditional topics as an important part of their professional education, they do not necessarily feel confident or competent in these areas. Establishing a conscious effort to teach these topics and to emphasize their importance during training will enhance residents' self-image, performance, and potential as future leaders. 相似文献
78.
Li JM Singh MJ Itani M Vasiliu C Hendricks G Baker SP Hale JE Rohrer MJ Cutler BS Nelson PR 《Journal of vascular surgery》2004,39(5):1074-1083
OBJECTIVE: Smooth muscle cell proliferation is a major pathophysiologic factor in injury-induced neointimal hyperplasia and recurrent stenosis. We have demonstrated that recombinant human thrombomodulin (rTM) inhibits thrombin-induced arterial smooth muscle cell proliferation in vitro. The purpose of this study was to investigate the effect of rTM on neointimal hyperplasia in vivo. METHODS: A rabbit femoral artery balloon injury model was used. Bilateral superficial femoral arteries were deendothelialized with a 2F arterial embolectomy catheter. rTM (145 microg/kg; 2.0 microg/mL in circulation) or Tris-hydrochloride vehicle control was administered intravenously during the procedure, then either discontinued (group A) or administered twice daily for an additional 48 hours (group B). Rabbits were euthanized at 4 days and at 1, 2, and 4 weeks, and femoral artery specimens were prepared with in situ perfusion fixation and paraffin embedding. Luminal, intima, media, and whole artery areas were quantitated with digital imaging computerized planimetry. Intima-media and lumen-whole artery ratios were calculated. The injury-induced inflammatory reaction was also evaluated with light microscopy, scanning and transmission electron microscopy, and immunohistochemical and immunohistofluorescence staining. RESULTS: In the buffer control group, neointimal hyperplasia after femoral artery balloon injury was evident at 2 weeks, and was pronounced at 4 weeks (P <.0001). Infusion of rTM significantly inhibited intimal hyperplasia at both 2 and 4 weeks (P <.0001). In group A, rTM reduced the intima-media ratio by 27% and 39% at 2 and 4 weeks, respectively. Extended administration of rTM (group B) resulted in inhibition of hyperplasia by 57% and 30% at 2 and 4 weeks, respectively, but failed to reach significance compared with the shorter exposure. rTM infusion significantly inhibited thrombosis (8.1-fold) compared with the buffer control group (P =.012). rTM had no significant effect on lumen area or lumen-whole artery ratio, but treated arteries demonstrated significantly less compensatory dilatation (P =.045), as measured by whole artery area in response to less intimal hyperplasia. rTM administration inhibited platelet adhesion and inhibition of neutrophil infiltration to a degree that approached statistical significance (P =.0675). CONCLUSIONS: Systemic intravenous administration of rTM significantly decreases neointimal hyperplasia and improves patency in the rabbit femoral artery after balloon injury. In addition to exhibiting antithrombotic and antiproliferative effects, rTM may also invoke an anti-inflammatory mechanism, and may alter vascular remodeling in a multidimensional role to inhibit recurrent stenosis after arterial injury. 相似文献
79.
Comparison of MRI and CT for detection of acute intracerebral hemorrhage 总被引:14,自引:0,他引:14
Kidwell CS Chalela JA Saver JL Starkman S Hill MD Demchuk AM Butman JA Patronas N Alger JR Latour LL Luby ML Baird AE Leary MC Tremwel M Ovbiagele B Fredieu A Suzuki S Villablanca JP Davis S Dunn B Todd JW Ezzeddine MA Haymore J Lynch JK Davis L Warach S 《JAMA》2004,292(15):1823-1830
Context Noncontrast computed tomography (CT) is the standard brain imaging study for the initial evaluation of patients with acute stroke symptoms. Multimodal magnetic resonance imaging (MRI) has been proposed as an alternative to CT in the emergency stroke setting. However, the accuracy of MRI relative to CT for the detection of hyperacute intracerebral hemorrhage has not been demonstrated. Objective To compare the accuracy of MRI and CT for detection of acute intracerebral hemorrhage in patients presenting with acute focal stroke symptoms. Design, Setting, and Patients A prospective, multicenter study was performed at 2 stroke centers (UCLA Medical Center and Suburban Hospital, Bethesda, Md), between October 2000 and February 2003. Patients presenting with focal stroke symptoms within 6 hours of onset underwent brain MRI followed by noncontrast CT. Main Outcome Measures Acute intracerebral hemorrhage and any intracerebral hemorrhage diagnosed on gradient recalled echo (GRE) MRI and CT scans by a consensus of 4 blinded readers. Results The study was stopped early, after 200 patients were enrolled, when it became apparent at the time of an unplanned interim analysis that MRI was detecting cases of hemorrhagic transformation not detected by CT. For the diagnosis of any hemorrhage, MRI was positive in 71 patients with CT positive in 29 (P<.001). For the diagnosis of acute hemorrhage, MRI and CT were equivalent (96% concordance). Acute hemorrhage was diagnosed in 25 patients on both MRI and CT. In 4 other patients, acute hemorrhage was present on MRI but not on the corresponding CTeach of these 4 cases was interpreted as hemorrhagic transformation of an ischemic infarct. In 3 patients, regions interpreted as acute hemorrhage on CT were interpreted as chronic hemorrhage on MRI. In 1 patient, subarachnoid hemorrhage was diagnosed on CT but not on MRI. In 49 patients, chronic hemorrhage, most often microbleeds, was visualized on MRI but not on CT. Conclusion MRI may be as accurate as CT for the detection of acute hemorrhage in patients presenting with acute focal stroke symptoms and is more accurate than CT for the detection of chronic intracerebral hemorrhage. 相似文献
80.
Mitosis in human cells is initiated at the end of G2 by activation of the Cdc2/cyclin B complex. Activation occurs by dephosphorylation of the inhibitory residues, threonine 14 (T14) and tyrosine 15 (Y15), on Cdc2 by the Cdc25C phosphatase. Entry into mitosis is regulated by the subcellular relocalization of Cdc2/cyclin B, which is rapidly imported into the nucleus at the end of G2. Here, we show that polo-like kinase 3 (Plk3) is able to phosphorylate Cdc25C primarily on S191, and to a lesser extent on S198 in vitro, both of which are within a nuclear exclusion motif. Following transfection, the S191D Cdc25C mutant leads to an enhanced accumulation of Cdc25C in the nucleus, while the S191A mutant facilitated the Cdc25C nuclear exclusion. Furthermore, translocation of Cdc25C to the nucleus was accompanied by a decrease in Cdc2 phosphorylation on Y15. Plk3-WT overexpression led to a sharp increase in Cdc25C nuclear accumulation, while Plk3-KD overexpression failed to do so. The effect of Plk3 overexpression on Cdc25C was reversed by coexpression of a Plk3 siRNA. These results support a role for the polo kinases in coordinating the translocation and perhaps the timing of both Cdc25C and its target Cdc2/cyclin B to the nucleus upon entry into mitosis. 相似文献