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61.
Segmented cine MRI generally requires breath-holding, which can be problematic for many patients. Navigator echo techniques, particularly successful for free-breathing coronary MRA, are incompatible with the acquisition strategies and SSFP pulse sequences commonly used for cine MRI. The purpose of this work is to introduce a new self-gating technique deriving respiratory gating information directly from the raw imaging data acquired for segmented cine MRI. The respiratory self-gating technique uses interleaved radial k-space sampling to provide low-resolution images in real time during the free-breathing acquisition that are compared to target expiration images. Only the raw data-producing images with high correlation to the target images are included in the final high-resolution reconstruction. The self-gating technique produced cine series with no significant differences in quantitative image sharpness to series produced using comparable breath-held techniques. Because of the difficulties associated with breath-holding, the respiratory self-gating technique represents an important practical advance for cardiac MRI. , Inc.  相似文献   
62.
The prognostic value of prostate specific antigen was evaluated to predict disease progression after endocrine therapy in patients with prostatic cancer. A total of 73 patients was studied (6 with stage B2, 16 with stage C, 9 with stage D1 and 42 with stage D2 disease). Endocrine therapy included bilateral orchiectomy, diethylstilbestrol diphosphate and luteinizing hormone-releasing hormone analogue. Pre-treatment serum prostate specific antigen levels were determined in all patients with an enzyme immunoassay kit. During a followup of 4 to 68 months (average 24 months) clinical disease progression occurred in 24 of the 73 patients. The pre-treatment prostate specific antigen level by itself did not predict disease progression. Changes in prostate specific antigen level with treatment were correlated with the interval to disease progression in the 44 patients who had prostate specific antigen determinations at regular intervals after endocrine therapy and whose initial level was greater than 10 ng./ml. Patients who had a decrease in the prostate specific antigen levels of 80% or more within 1 month after the beginning of therapy survived significantly longer free of disease progression (p less than 0.001). Patients whose prostate specific antigen level remained elevated for more than 3 months had a high risk of disease progression within 2 years. Our study suggests that patients with the more favorable prognosis can be identified early, after 1 to 3 months of endocrine therapy, by the rapid decrease in the prostate specific antigen levels.  相似文献   
63.
The present case report describes a case of ganglioglioma with a distinct sarcomatous component in the left temporal lobe of a 59‐year‐old Japanese man. Neoplastic neuroglial tissue contained both benign and anaplastic glial components with a MIB‐1 labeling index of 0.1% and 12.0%, respectively. Sarcomatous tissue adjacent to the anaplastic glial tissue was dominated by pleomorphic fibroblastic cells with a MIB‐1 labeling index of 10.8%. They were immunoreactive for smooth muscle actin, type IV collagen, and alpha 1 antitrypsin, but not for desmin and CD34. Interestingly, some of the sarcomatous cells were double‐positive for smooth muscle actin and GFAP. The p53 protein had accumulated in the anaplastic astrocytes and sarcomatous cells, but direct DNA sequencing of PCR products failed to detect any mutation in the p53 gene (from exon 4 to exon 10).  相似文献   
64.
The possible colocalization of oxytocin (OT) and galanin (GAL) was studied by combining, on the same cryostat sections, in situ hybridization (ISH) for OT mRNA with a tritiated oligonucleotide probe and immunohistochemistry (ICC) of GAL. Many cells were either labelled by ISH (OT mRNA containing cells), or by ICC (GAL containing cells). Moreover, some magnocellular neurons in the supraoptic and paraventricular nuclei were labelled for both OT mRNA and GAL. These results demonstrate that some magnocellular neurons of the rat hypothalamus contain both GAL and OT. This approach is suitable for studying the intracellular distribution of OT gene expression and mature GAL under different physiological or experimental conditions.  相似文献   
65.
A successful case of simultaneous modified Bentall' procedure, MVR and sternoplasty was presented for a 42 years old man of Marfan's syndrome who had funnel chest, combined with mitral regurgitation, aortic regurgitation and annuloaortic ectasia. A few reports of one stage operation for the combination of funnel chest and heart disease in Marfan's syndrome has been published. A median sternotomy was made, with total cardiopulmonary bypass, heart was arrest and cor cooling hypothermia with crystalloid cardioplegic solution. Mitral valve was replaced with #31 B-S prosthetic valve. The ascending aorta proximal to the innominate artery and the aortic valve were replaced en-bloc with composite graft made of a vascular graft and aortic valve prostheses. Coronary artery orifices cut to the button-shaped, were sutured to the composite graft. Finally, sternoplasty was completed through modified Ravitch sterno-elevation. This is the first report in Japanese journals.  相似文献   
66.
The histochemical demonstration of iron and the iron content was examined in the brain of a case of the special type of hepatocerebral encephalopathy (HCE). The patient had suffered from a liver disease since 36 years old. At 44 years old, she experienced the first attack of twilight state with flapping tremor. She had predilection for eating beans. Her personality gradually became euphoric with the recurrent episodes of unconsciousness. At 54 years old, she died of the complication of melena, renal insufficiency and pneumonia. The liver showed cirrhotic changes and iron content of liver was 0 or 1 after MacDonald's criterion scale. The histopathological findings of the brain showed the characteristic changes of HCE, which were incomplete softening and spongy state pseudolaminarilly extending in the deep layer of the cerebral cortex, the proliferation of the severely changed Alzheimer 2 type glia with or without intranuclear carmine positive substance. The deparaffinized sections, 20 mu in thickness, which were not fastened on slides were used for the histochemical study of iron, because iron deposits displaced inside of the brain tissues when the paraffin sections were fastened on slide glasses in the constant-temperature bath. The iron deposition was found in the central gyrus, superior temporal gyrus, medial and lateral occipito-temporal gyrus and middle temporal gyrus of occipital lobe. The iron accumulated in the ground substance, glia cell bodies, glia nuclei and unknown bodies in the 3-6 layers of cerebral cortex of these gyri. The iron accumulation demonstrated histochemically in other parts of the brain were group 1, 2 by Spatz, mammillary body, glia cell bodies in cerebellar white matter and pons.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
67.
Abstract: In an experimental dog model of acute biventricular failure, the effects of left ventricular (LV) assist on renal hemodynamics and function were evaluated. After the induction of severe cardiac failure by multiple ligation of the coronary arteries, LV assist with a 40 ml pneumatic pulsatile pump was initiated, and the aortic flow was maintained at control values. The right atrial pressure (RAP) rose to 21.3 mm Hg with the appearance of profound right ventricular (RV) failure. Renal arterial blood flow (RAF) decreased to about 60% of the control value after 2 h of LV assist. The urine volume decreased and renal function deteriorated progressively. RV assist decreased the RAP to 4.8 mm Hg, and the reduced RAF recovered. After 3 h of RV assist, the RAF returned to initial values and the urine volume increased, but renal function did not recover. Advanced biventricular failure with elevated RAP during LV assist reduced renal perfusion and impaired renal function and may be an indication for early RV assist  相似文献   
68.
OBJECTIVE Little information is available regarding the regulation of serum acid-labile subunit (ALS) in human disease. We have studied alterations in serum ALS of the insulin-like growth factor (IGF) ternary complex in children with untreated insulin-dependent diabetes mellitus (IDDM) and subjects with severe burns before and after insulin therapy. In addition, we have investigated the effect of insulin plus GH on serum ALS in burn patients. DESIGN Serum samples were obtained from children with newly diagnosed and untreated IDDM before the initiation of insulin therapy and 1 month thereafter. Serum samples were also obtained from adult patients with severe burns who were on a continuous infusion of a carbohydrate-rich enteral diet via nasogastric and duodenal catheters under basal conditions, after a 1-week period of continuous insulin infusion, and after an additional week of insulin plus recombinant GH. PATIENTS Twenty children and adolescents with untreated IDDM, aged 1.2–16 years, and 6 young adult patients with severe burns aged 17–28 years were studied longitudinally. Control sera were obtained from age, sex and pubertal status matched subjects (for children with IDDM) and from fed healthy adults. MEASUREMENTS Serum insulin, GH, cortisol and IGF-I were measured by radioimmunoassay, and serum ALS levels were assessed by Western immunoblot before and after treatment periods. RESULTS Serum ALS levels were lower in untreated children with IDDM (69 ± 6% of control children). Insulin therapy significantly increased serum ALS (79 ± 5%, P<0.05) in these children. Patients with severe burns also had lower serum ALS levels (79 ± 10% of control adults). After one week of insulin therapy serum ALS levels increased to 90 ± 15% of control values (P<0.05). Addition of GH to insulin therapy for another week did not significantly further increase serum ALS levels (95 ± 27%). Serum IGF-I concentrations increased nearly 2.5-fold in diabetic subjects and fourfold in burn subjects at the end of the study periods. There were no proteolytic fragments of ALS in the sera studied. The deglycosylation pattern of ALS did not differ between diabetic and control sera. CONCLUSION Serum ALS levels were diminished in children with untreated IDDM and were partially restored after the initiation of insulin therapy. Serum ALS levels were also diminished in patients with severe burn injury and restored by insulin treatment. Addition of GH to insulin therapy did not significantly increase serum ALS levels over levels obtained during insulin therapy alone. These decreases in serum ALS were smaller than the decrease in serum IGF-I concentrations in both conditions, suggesting that IGF-I is the limiting factor for the ternary complex formation in the catabolic states. Insulin may regulate circulating ALS levels in catabolic states and helps to restore the IGF system.  相似文献   
69.
The results of treating 12 consecutive patients with unresectable colorectal hepatic metastases with a hepatic arterial infusion of high-dose Adriamycin, 100–120 mg/m2, using hepatic venous isolation (HVI) and charcoal hemoperfusion (CHP) are reported herein. Adriamycin was administered over 5–15 min under extracorporeal drug elimination by HVI-CHP. HVI was percutaneously accomplished by either the double-balloon technique using a Fogarty occlusion catheter (8/22F) or a balloon-tipped catheter (16F). During the infusion, isolated hepatic venous blood was filtered by CHP and pumped into the left axillary vein. There were no lethal complications, and good hemodynamic tolerance to HVI-CHP was confirmed. Tumor liquefaction accompanied by a sharp decrease in serum carcinoembryonic antigen levels by more than 50% of pretreatment levels was observed in 6 of the 12 patients 1 month after treatment. Apart from chemical hepatitis, which developed in 11 (92%) of the patients, the Adriamycin toxicities were well controlled following the development of nausea and vomiting in 2 patients (17%), leukopenia <2,000/mm3 in 3 (25%), and gastric ulcer in 1 (8%). These results indicate that this method is a safe and useful procedure for otherwise hazardous high-dose intraarterial chemotherapy in patients with unresectable hepatic tumors.  相似文献   
70.
Expression of glutathione S-transferase placental form (GST-)in human lung carcinoma tissue taken at autopsy or biopsy wasinvestigated immunohistochemically. All of 34 cases of squamouscell carcinomas, including poorly, moderatelyand well-differentiatedexamples were shown to stain positively for GST-. Poorly differentiatedadenocarcinomas were, however, negatively stained (0/5 cases),while moderately and well differentiated adenocarcinomas werefound tostain with GST- at rates of 69% (9/13 cases) and 71%(5/7 cases), respectively. Six cases of small cell carcinomasexamined were all negative. The results indicate that GST- maybe a useful marker fornon-small cell type lung cancer, especiallysquamous cell carcinoma which is in agreement with findingsfor rat lung neoplastic lesions reported previously.  相似文献   
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