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791.
792.
The purpose of this study was to determine the incidence of left ventricular (LV) thrombosis and systemic embolism in 14 patients with LV assist systems. Echocardiography was used to detect LV wall motion abnormalities, intracavitary smoke-like echoes and thrombosis, and the effect of anticoagulant therapy was serially examined. During full assist of the circulation, the aortic valve did not open in any patient. Smoke-like echoes were observed in 9 patients (64%) and thrombi in 8 (57%). The thrombus developed within the first 3 assist days. Systemic anticoagulant therapy decreased the thrombus size in only 3 patients, but there was a possibility of intracranial or mediastinal bleeding in other 3 patients. Systemic embolism was noted in 7 of 11 autopsy patients (64%). The characteristic finding was that there were multiple embolized organs, such as the brain, kidneys, spleen and liver, in all patients. Development of a thrombus is a serious complication in all patients with LV assist systems. However, the problem does not lie in the assist system but in the left ventricle of the patient's own heart. It is also noteworthy that systemic anticoagulation is not effective for an LV thrombus. A new method of assisting the failing heart, or a new anticoagulant delivery technique for the LV cavity to prevent LV thrombus development is needed.  相似文献   
793.
The gap between the tips of the anterior and posterior mitral leaflets was studied to assess the significance of this gap in the diagnosis of mitral valve prolapse. The subjects were 39 patients in whom the gap was seen and the mitral valve did not exceed the mitral annular line in systole on two-dimensional echocardiography. Forty eight healthy subjects, in whom phonocardiography disclosed no abnormalities, served as controls. The site of the gap as well as the site and severity of mitral regurgitation were assessed with two-dimensional echocardiography and Doppler flow imaging. The incidence of mitral regurgitation was 82%, which was comparable to that in the controls (67%). The site of the gap was consistent with that of regurgitation. The gap was also seen in a low percentage of healthy subjects, but clinically significant mitral regurgitation did not accompany the gap in healthy subjects including the gap-carrying controls. On the other hand, many of the gap-carrying patients showed clinically significant mitral regurgitation. Also the fact that a gap between the tip of the anterior and posterior mitral leaflets was found to be frequently accompanied by phonocardiographical features corresponding to mitral valve prolapse indicates that the presence of a gap is a significant finding.  相似文献   
794.
795.
796.
Measurement of PCNA labeling index in astrocytic tumors]   总被引:1,自引:0,他引:1  
PCNA (proliferating cell nuclear antigen) is said to be present specifically in the nucleus of proliferating cells. The PCNA labeling index (PCNA LI) of astrocytic tumors was measured and compared with histological types or prognosis. The specimens from 44 patients were fixed in a 10% formalin solution, and embedded in paraffin. The 3 microns-sections were stained immunohistochemically with anti-PCNA monoclonal antibody (PCIO, Novocastra) using an ABC method. The percentage of PCNA-positive-cells was determined by counting 2000 cells, and identified as PCNA LI. All of the PCNA-positive-cells showed diffuse nucleoplasmic staining. The averages of PCNA LIs in each pathological type were calculated and evaluated statistically. Although differences in averages of PCNA LIs among pilocytic, gemistocytic, fibrillary astrocytoma were not significant, there was a significant difference between anaplastic astrocytoma and glioblastoma. The relationship between PCNA LIs and the prognoses for 43 patients was studied. Forty-three patients were classified into 3 groups (over 22%, 7 to less than 22%, and less than 7%) according to PCNA LIs. The survival data in the 3 groups were analyzed, and differed significantly in the survival rates. Furthermore, twenty-three patients of anaplastic astrocytoma and glioblastoma were classified into two groups (over 22% and less than 22%). Likewise, the two groups differed significantly. In summary, pathological type and prognosis were closely related to PCNA LI in astrocytic tumors. Therefore, we thought measurement of PCNA LI would make it more possible to analyze clinically the proliferating activity of astrocytic tumors, and to care for patients more effectively.  相似文献   
797.
Recent studies related to the fibula flap have disagreed regarding the anatomy of the cutaneous branches of the peroneal artery. To clarify this issue, various dissections of 35 injected fresh cadaver legs were done. Identifiable skin branches were found in 23 of 25 dissections. Skin branches from the proximal third of the peroneal artery always travelled an intramuscular course. Skin branches from the distal two-thirds of the peroneal artery were usually affixed to the posterior crural septum. Legs with peroneal artery skin branches had from three to seven branches (average: 4.7); each branch contributed to the fibular periosteal blood supply. The most reliably found skin branch was located within 2 cm of the fibula midpoint. These findings reinforce the fact that a large skin island supplied by branches of the peroneal artery can be harvested with the fibula flap, and that the most reliable cutaneous vessels are found in the lower two-thirds of the leg, run posterior to the fibula in the posterior crural septum, and are always associated with muscular side branches.  相似文献   
798.
799.
To elucidate the characteristics of venous inflow into the heart in cardiac tamponade, transmitral (TMF), transtricuspid (TTF) and superior vena cava (SVC) flows were examined using pulsed Doppler echocardiography in nine mongrel open-chest dogs. Cardiac tamponade was produced by the slow infusion of warmed normal saline into the pericardial sac. With increment of pericardial infusion, right atrial collapse (RAC) developed followed by right ventricular collapse (RVC). The systemic blood pressure became depressed and the left ventricular end-diastolic diameter decreased, even in the RAC state, indicating that RVC is not of the primary significance for cardiac tamponade. Characteristically, peak velocities of TMF and TTF in early diastole decreased concomitantly with RAC and RVC. Neither early diastolic filling time nor its acceleration time was altered during tamponade. These changes in blood flow were accompanied by decrements of transmural filling pressure and abnormal motion of the right ventricle. In SVC flow, the diastolic wave characteristically disappeared. This change seemed to be a reflection of the decrease in peak velocity of early diastolic filling flow into the right ventricle. That is, impairment of cardiac relaxation during cardiac tamponade is represented as decreased filling flow velocity in early diastole.  相似文献   
800.
Aims  It is well documented that maternal morbidity and neonatal morbidity and mortality increase alike in high-order multiple (HOM) births. There have, however, been few reports concerning the costs of maternal and neonatal medical care associated with HOM births. This is the first such report on the situation in Japan. Materials and methods  All triplet and quadruplet pregnancies managed at this institution from before 16 weeks’ gestation, and delivered at no earlier than 22 weeks’ gestation, between 1997 and 2002 were included. Prophylactic cervical ligature, hospitalization to prevent premature labor from 23 weeks’ gestation until delivery, and delivery by cesarean section, were all routine for HOM pregnancies. All women with singleton and twin pregnancies, who underwent in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) and also delivered their babies at no earlier than 22 weeks’ gestation at this institution, between 1997 and 2002, were also examined as controls. Prophylactic cervical ligature, preventive hospitalization, and cesarean section were not routine in the control group. Results  The average gestational ages at delivery in singleton (n = 58), twin (n = 21), triplet (n = 14) and quadruplet (n = 1) pregnancies, were 39.4, 35.6, 31.9 and 25.1 weeks, respectively (P < 0.001 by Anova). Birthweights were 2886 ±425 g, 2117 ± 623 g, 1430 ± 373 g, and 633 ± 77 g (mean ± SD), respectively (P < 0.001). The average inpatient medical care cost for mother and child(ren), from maternal admissions after 12 weeks’ gestation to the discharge of all family members from hospital, was ¥703 279 yen (∼US$5861), ¥4 903 270 (∼US$40 861), ¥11 810 327 (∼US$98 419), and ¥44 961 000 (∼US$374 675), respectively (P< 0.001). Conclusion  The present study outlined the high costs of medical care for HOM pregnancies. Not only from a medical viewpoint, but also from the viewpoint of medical costs, it is important to avoid HOM pregnancies as a result of infertility treatment.  相似文献   
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