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81.
82.
Preclinical evaluation of cardiac drugs may require evaluation of cardiac function in intact animals. To optimize the quality of radionuclide measurements of ventricular function in small animals, a comparison was made of gated blood-pool scans recorded with five blood-pool radiopharmaceuticals (99mTc-labeled human polyclonal IgG, 99mTc-human serum albumin labeled by two methods, and red blood cells radiolabeled with 99mTc via in vivo and in vitro methods) in rats and three pinhole apertures in hamsters. The quality of the radiopharmaceuticals was evaluated by comparing count density ratios (LV/BACKGROUND and LV/LIVER) and ejection fractions recorded with each agent. The edge definition of the left ventricle and count rate performance of the 1-, 2-, and 3-mm apertures was evaluated in hamsters. In general, the images obtained with the radiolabeled cells were superior to those obtained with the labeled proteins and no significant differences between the protein preparations were detected. Left ventricular ejection fractions calculated with all five radiopharmaceuticals were not significantly different. The best quality images were obtained with the 1-mm pinhole collimator. Ejection fraction and acquisition time were inversely related to aperture size. A good compromise between resolution and sensitivity was obtained with the 2-mm pinhole collimator.  相似文献   
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84.
BACKGROUND: The most important factors for prognosis of cervical cancers are age and histological criteria such as the tumor size, the involvement of lymph nodes, lympho-vascular space involvement as well as microvessel involvement and poor tumor differentiation (grading 3). Here we present the results of concomitant chemo-radiation at high-risk situation of patients with cervical cancer after surgery. PATIENTS AND METHODS: The study comprised 34 patients with median age of 40 years (26-63 years) after Wertheim surgical technique for cervical cancer at the FIGO Stages IB (n = 19) and IIB (n = 15). All patients were treated between November 1995 and June 1999 by a schedule of concomitant chemoradiation. The indication for this treatment was given by the positive histological proof of lymph node metastasis, microvessel or lympho-vascular space involvement as well as a G3 grading. The chemo-therapy was given in week 1 and 5 (day 1-5 and day 29-33). The dosage of cisplatin was 20 mg/m2/d on every day and 5-FU was given as a 120-h infusion with 600 mg/m2/d. The external beam radiotherapy was applied to the pelvis with 1.8 Gy per fraction up to 50.4-54 Gy. In two patients the paraaortal region was irradiated too because of the involvement of these lymph nodes. RESULTS: The median observation time was 48 months (3-68 months). 30 patients are alive (88%) in complete response. Four patients died. The mean survival was 61 +/- 3 months. We have seen only slight acute toxicities of grade 1 and 2. Three patients suffered from a grade 3 diarrhea and three patients developed a grade 3 leukopenia. In seven patients we found a secondary lymphedema as a late toxicity. CONCLUSION: The concomitant chemoradiation containing cisplatin in high-risk situation for cervical cancer after surgery improves the outcome and survival in these patients.  相似文献   
85.
锌酞菁脂质体光动力作用引起小鼠肿瘤的细胞程序性死亡   总被引:3,自引:1,他引:3  
电镜观察了锌酞菁脂质体光动力作用引起小鼠MS-2纤维肉瘤的形态学变化。发现其作用很强,并对肿瘤细胞有明显的直接影响。肿瘤细胞的结构表现出明显的程序性细胞死亡(apoptosis,programmedceldeath)的特点:胞核染色质凝聚边集、核固缩、核破裂、染色质凝块流失、胞质内吞噬现象、胞膜表面肿胀粗钝的胞突形成、细胞碎裂等。加深了对锌酞菁脂质体光敏作用机理的认识,但其详细的发生机制和调节途径有待阐明。  相似文献   
86.
A cell line, designated RS4;11, was established from the bone marrow of a patient in relapse with an acute leukemia that was characterized by the t(4;11) chromosomal abnormality. The cell line and the patient's fresh leukemic cells both had the t(4;11)(q21;q23) and an isochromosome for the long arm of No. 7. Morphologically, all cells were lymphoid in appearance. Ultrastructurally and cytochemically, approximately 30% of the cells possessed myeloid features. The cells were strongly positive for terminal deoxynucleotidyl transferase. They were HLA-DR positive and expressed surface antigens characteristic for B lineage cells, including those detected by anti-B4, BA-1, BA-2, and PI153/3. Immunoglobulin gene analysis revealed rearrangements of the heavy chain and kappa chain genes. The cells lacked the common acute lymphoblastic leukemia antigen and antigenic markers characteristic of T lineage cells. The cells reacted with the myeloid antibody 1G10 but not with other myeloid monoclonal antibodies. Treatment with 12-O-tetradecanoyl- phorbol-13-acetate induced a monocyte-like phenotype demonstrated by cytochemical, functional, immunologic, and electron microscopic studies. The expression of markers of both early lymphoid and early myeloid cells represents an unusual phenotype and suggests that RS4;11 represents a cell with dual lineage capabilities. To our knowledge, RS4;11 is the first cell line established from t(4;11)-associated acute leukemia.  相似文献   
87.
In order to study the metabolism of high density lipoprotein (HDL)-carried sterol in the rat, human HDL was reconstituted with [14C]cholesterol and [3H]cholesteryl ester. After iv injection into immature PMSG-human CG primed rats pretreated with 4-aminopyrazolopyrimidine and aminoglutethimide, there was time-dependent accumulation of 3H and 14C in various organs which reached a maximum by 15-90 min. On a milligram wet weight basis, uptake of 3H and 14C was greatest in the adrenals, next in ovaries, followed by the liver, with little uptake by kidneys and spleen. On an organ basis, accumulation was greatest by the liver. At 15-45 min post injection, 60% of the 3H in the ovary was in free sterol, indicating hydrolysis of the accumulated cholesteryl esters, whereas 95% of the 3H in serum remained in sterol esters associated with HDL. Coadministration of excess unlabeled HDL, but not human low density lipoprotein, reduced accumulation of radioactivity by the ovaries and adrenals by 60%, indicating a specific and saturable uptake process. Granulosa cells cultured in lipoprotein-deficient medium with reconstituted HDL formed 3H- and 14C-labeled 20 alpha-hydroxypregn-4-en-3-one. Over a 24-h period, utilization of both [14C]cholesterol and [3H]cholesteryl ester was linear, but rates of utilization of the two sterol moieties were not parallel. There was preferential uptake and utilization of free sterol. A dose-response study demonstrated a Michaelis-Menten constant (Km) of 40-60 micrograms sterol/ml for both free and esterified cholesterol. Lysosomotropic agents (chloroquine and NH4Cl) had no effect on utilization of either free or esterified cholesterol for steroidogenesis but reduced degradation of 125I-labeled low density lipoprotein apoprotein. These findings lend further support to the concept of a distinct HDL pathway in steroidogenic cells of the rat, which involves 1) preferential uptake and utilization of free cholesterol from HDL and 2) does not require lysosomal activity.  相似文献   
88.
Although congestive heart failure has been reported with the combination of a beta blocker and either verapamil or nifedipine, it has not previously been reported for combination therapy that includes diltiazem. The following case documents the occurrence of clinical congestive failure in a patient with baseline left ventricular dysfunction and severe angina pectoris. Although the patients had tolerated propranolol therapy for years without difficulty, and high-dose diltiazem monotherapy with an excellent clinical response, the combination of diltiazem and propranolol resulted in the development of congestive heart failure. Thus, although generally well tolerated, given the suitable scenario of reduced left ventricular function, the combination of diltiazem and a beta blocker may adversely affect left ventricular performance.  相似文献   
89.
ObjectivesTo evaluate the concordance between testicular tumor size and benign histology in order to identify a cut-off size, below which the rate of benign lesions would be highest.Methods and materialsDuring the years 1995–2008, we performed 131 consecutive testicular operations for testicular tumors. Ten of these were testicular preserving surgery, whereas the other 121 patients had radical orchiectomy. We searched for the rate of benign lesions in the following 3 groups of tumor diameter: 10 mm or less, 11–20 mm, and greater than 20 mm. ROC analysis was used to find the optimal size cut-off below which the rate of benign lesions would be highest.ResultsBenign lesions were found in 11 patients (8%), including epidermoid cyst (n = 4), Leydig cell tumor (n = 3), fibrosis (n = 1), adenomatoid tumor (n = 2), and 1 patient with a simple cyst. Small tumor size strongly correlated with benign histology. The mean diameter of benign vs. malignant lesions was 15 mm and 41 mm, respectively (P < 0.05). The rate of benign lesions in tumors with a diameter of 10 mm or less, 11–20 mm and greater than 20 mm was 50%, 17%, and 2%, respectively. Receiver Operating characteristic (ROC) analysis with 87% sensitivity and 83% specificity revealed a cut-off value of 18.5 mm tumor diameter below which the proportion of benign lesions was 38.5% compared with 2% above it (P < 0.05).ConclusionsWhile benign lesions comprise only 8% of all testicular tumors, their proportion among small lesions is much higher. With a size cut-off of 18.5 mm, 38.5% of smaller lesions are benign. These findings support consideration of testicular exploration for small testicular lesions aiming at preservation rather than predetermined radical orchiectomy.  相似文献   
90.
The increasing use of digitally formatted imaging systems requires high-quality interactive gray-scale computer raster graphics systems for the management, display, and analog film recording of digital image and alphanumeric information. These systems are a combination of computer hardware and software and implement a set of graphics protocols. This paper describes a set of interactive graphics protocols that has been developed for clinical use.  相似文献   
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