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101.
We carried out a morphometric study on the myelinated fibers in the anterolateral funiculus (ALF) and lateral corticospinal tract (LCS) in the cervical segment of the spinal cord of 13 patients with classic amyotrophic lateral sclerosis (ALS), 6 of whom had been on a respirator: 5 age-matched subjects were used as controls. The results obtained revealed that: (1) the fiber-size distributions of the myelinated fibers in the ALF and LCS of the control subjects had peaks at 2 m; (2) there were marked and significant losses of large myelinated fibers in the ALF and LCS of ALS patients; (3) the patients who required respirator support showed more severe degeneration in the ALF than those who required none; and (4) the degree of myelinated fiber loss in the LCS did not correlate with either the illness duration or the history of respirator use.  相似文献   
102.
The procedure of aspiration biopsy cytology by fine needle aspiration (ABC) is as option in establishing definitive diagnoses for breast cancers. In this series, a needle size of 21G was considered most suitable for ABC as well as flow cytometric DNA analysis. Histograms from fresh samples aspirated by fine needle clearly delineated a sharp peak in G&sup0;G(1) phases and also a better CV was obtained than with paraffin-embedded preparations. In addition, fresh samples gave more reliable DI and suggested the value of measuring nuclear DNA contents. It is believed that the prognoses of breast cancers are closely associated with DNA ploidy patterns. In this sense, flow cytometric DNA analysis of fresh samples of ABC is regarded as important in clinical use.  相似文献   
103.
104.
Seventeen quaternary protoberberine alkaloids related to berberine 1 were tested for antimalarial activity in vitro against Plasmodium falciparum and structure-activity relationships are proposed. The activity of the protoberberine alkaloids was influenced by the type of the oxygen substituents on rings A, C and D and the position of the oxygen functions on ring D. The position of the oxygen functions on ring D and the type of the oxygen substituents at the C-13 position (ring C) strongly influenced the activity. Shifting the oxygen functions at C-9 and C-10 to C-10 and C-11 on ring D resulted in a significant increase in the activity. Compounds bearing a methylenedioxy function at C-2 and C-3 (ring A) or C-9 and C-10 (ring D) showed higher activity than those which have methoxy groups at the same positions. Introduction of a methoxy group into the C-1 position (ring A) decreased the activity. Replacement of a hydroxy group at C-2 or C-3 (ring A) by a methoxy group led to a reduction in the activity. Displacement of a hydroxy function at C-13 (ring C) by the oxygen substituents such as OMe, OEt, OCOOEt, and OCON(Me)2 reduced the activity. In the same replacement at C-9 (ring D), the activity depended upon the type of the oxygen function. Six protoberberines displayed more potent activity than berberine 1. The activity decreased in the order: 10, 11, 17 and 18 > 7 and 8 > 1.  相似文献   
105.
Delayed single-photon emission tomograpic (SPET) images after an intravenous bolus injection of iodine-123 iomazenil have been used as a relative map of benzodiazepine receptor binding. We determined the optimal scan time for obtaining such a map and assessed the errors of the map. SPET and blood data from six healthy volunteers and five patients were used. A three-compartment kinetic model was employed in simulation studies and analyses of actual data. The simulation studies suggested that, in the normal brain, the scan time at which a single SPET image best represented the relative receptor binding was 3.0–3.5 h post-injection. This finding was supported by actual data from the volunteers. The simulation studies also suggested that the optimal scan time was not greatly changed by the variability of the input functions, and that the error in the SPET image contrast in the vicinity of the optimal scan time was not increased by changes in the tracer kinetics in the entire brain. The SPET image contrast in the patients at 3.0 h post-injection agreed well with the reference receptor binding estimated by kinetic analysis, with a mean error of 3.6%. These findings support the use of a single SPET image after bolus injection of [123I]iomazenil as a relative map of benzodiazepine receptor binding. For this purpose, a SPET scan time of 3.0-3.5 h post-injection is recommended.  相似文献   
106.
A huge phyllodes tumor of the breast that appeared grossly malignant in a 43-year-old woman is described. The patient suffered from a large breast tumor that suddenly increased in size over 5 months to occupy the entire breast. The tumor was hard, ulcerated and 20 cm in greatest diameter. Diagnostic imaging (US, CT and MRI) demonstrated a circumscribed mass with a large cystic cavity. She underwent total mastectomy under a diagnosis of malignant breast tumor. Grossly, the cut surface of the tumor showed a large cystic cavity surrounding a fleshy, hemorrhagic and necrotic mass with a lobulared or trabeculared appearance. Unexpectedly, benign phyllodes tumor (PT) without any stromal overgrowth was diagnosed histologically. She has been doing well since total mastectomy. In our case and in many other reported cases, PT does not show any distinctive correlation between pathologic findings and tumor behavior. Thus wide local excision is the preferred initial treatment for PT.  相似文献   
107.
To determine the availability and limitations of the detection of ischemic lesions by stress thallium-201 myocardial SPECT as the daily routine procedure, we compared and evaluated the detectability of the quantitative analysis (%uptake and washout rate (WR)) and visual evaluation in 104 patients with effort angina and 17 normal subjects. Visual evaluation combined with WR analysis resulted in significantly higher sensitivity (88.0%) but lower specificity (60.2%) than the other methods. The sensitivity by visual evaluation was quite low in multivessel disease (MVD), and in the regions supplied by mild coronary stenosis or by the left circumflex artery. These were markedly improved by combining visual evaluation and WR analysis, but sensitivity in the MVD group was unsatisfactory even with this analytic method in comparison with the single vessel disease group. One of the causes of low sensitivity in the MVD group might be the "true negative": No induction of the ischemia in the regions of milder stenosis, or the regions supplied by the collateral coronary flow. We therefore conclude that the combination of visual evaluation as a qualitative analysis and WR analysis as a quantitative analysis, is the most useful daily routine procedure as a screening test for detecting ischemia.  相似文献   
108.
Present features and functions of ethics committees in 80 Japanese medical schools were surveyed through inquiries to those institutes by the author. Seventy nine schools have already started their own committees in each campus by the end of 1990, and the remaining one is preparing for its start in near future. The major role of the ethics committee may be said to roughly correspond to that of the Institutional Review Boards (IRB) in the USA, although a role of the hospital ethics committee has been played in addition to its proper functions in many schools. Among many problems two major drawbacks seem necessary to be removed urgently. The first one is an inappropriate composition of the committee in the majority of schools. More members from the outside of the campus, younger generations, and female reviewers should be added to the committee. The second point is the essentially closed review systems in most schools. The process of the review has not been effectively opened to the public yet, even in case in which no privacy of the patients or volunteers appears in the discussion. Several schools are preparing for opening now and the situation will be improved gradually. It was fortunate that the ethics committees in Japanese medical schools were founded by wills and efforts of members of each campus without having any suggestions, recommendations, or orders from the national government or other officials.  相似文献   
109.
Endocrine surgeons have had an important role in the management of hyperthyroidism due to either Graves' disease or toxic nodule(s). Since alternative treatments such as antithyroid drugs or radioiodine are also available, the decision-making for management should be based on clear assessment of advantages and limitations of each of the treatment options. Surgery provides rapid resolution of these conditions, and cure rates are high, although it may be associated with perioperative complications and postoperative thyroid dysfunction. The authors' experience in the surgical treatment of hyperthyroidism and a review of the recent literature are outlined in this report.  相似文献   
110.
It is important to understand the main variations of the biliary and vascular elements inside the plate system for hilar bile duct carcinoma because all variations of these elements occur in this plate system. The plate system consists of the hilar plate, cystic plate, and umbilical plate which cover the extrahepatic vascular system and are fused with the hepatoduodenal ligament. The bile duct and vascular system that penetrate the plate system form Glisson's capsule in the liver, but the caudate branch and the medial segmental branch are exceptions. The bile duct and hepatic artery accompanying the plate system can be exfoliated from the portal vein with numerous lymph ducts and nerves. The bile ducts in the right hepatic lobe are classified into 4 types, and the standard type is present in 53-72% of cases. In the left bile duct, the medial segmental bile duct is connected in the vicinity of the hilar area in 35.5% of cases, and these cases should be treated the same as the caudate lobe in hilar bile duct carcinoma. Generally, there is little main variation of the portal vein (16-26%), but more variation in the hepatic artery (31-33%). During surgery for hilar bile duct carcinoma, it is important to observe the plate system and the many variations of the bile duct and vascular system.  相似文献   
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