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31.
Six kinds of human herpes viruses have been identified and classified on the basis of structure and characteristics. We studied the identification and classification of these types using PCR to amplify the virus-specific DNA sequences. This method showed higher sensitivity than the conventional method of virus isolation and culture for HSV and CMV detection. For each positive control, the viral DNA was amplified only when the complementary primers themselves were used. PCR apparently detects only the activated virus, because normal controls were negative when this method was used. Therefore, the present method is thought to closely reflect viral activation and infectious diseases in patients with latent infections.  相似文献   
32.
A case of a rare renal tumor showing characteristic histo-logic features is presented. The patient was a 54 year old female, whose renal tumor was incidentally detected on abdominal ultrasound (US) examination. Ultrasound, computed tomography and angiography findings were consistent with a diagnosis of renal cell carcinoma of the hypovascular type. Left nephrectomy was performed. The tumor, which measured 2.6 times2.6 times 2.5 cm, was located in the left renal cortex, and had a uniformly whitish-yellow cut surface and well-defined margin. Histologically, the tumor was characterlzed by its monomorphous growth pattern and was composed of uniformly small cells arranged in a tubular or rosette-like pattern. The tumor cells had scant cytoplasm and the nuclei were small, round and regular. These histo-logic features resembled the epithelial elements of a metanephric hamartoma in the nephroblastomatosis complex in infants. However, there was no mitosis and cellular atypia was minimal, suggesting benignity. According to these his-tologic features, the diagnosis of metanephric adenoma was made. Its clinicopathologic features are discussed.  相似文献   
33.
Bone bonding behavior of three kinds of apatite containing glass ceramics   总被引:1,自引:0,他引:1  
We have produced three kinds of apatite-containing glass ceramics of the same chemical composition: MgO (4.6), CaO (44.9), SiO2 (34.2), P2O5 (16.3), CaF2 (0.5) (in weight ratio). They contain different crystal combinations and have different mechanical properties. The first glass ceramic (A-GC) was prepared by heating a glass plate to 870 degrees C. It contains only oxy- and fluoroapatite (35 wt%). The second glass ceramic (A-W-GC), and the third (A-W-CP-GC), were prepared by heating glass powder compacts to 1050 degrees C and 1200 degrees C, respectively. A-W-GC contains oxyapatite and fluoroapatite (Ca10(PO4)6(O,F2] (35 wt%) and beta-wollastonite (40 wt%). A-W-CP-GC contains oxyapatite and fluoroapatite (20 wt%), beta-wollastonite (CaO X SiO2) (55 wt%), and beta-whitlockite (3CaO X P2O5) (15 wt%). The bending strengths of A-GC, A-W-GC, and A-W-CP-GC were 88MPa, 178MPa, and 213MPa, respectively, in air. Rectangular ceramic plates (15mm X 10mm X 2mm) were implanted into a rabbit tibia. Ten and 25 weeks after implantation, the segment of tibia with implant was excised for examination. The segment was held by a special jig and the traction breaking load (failure load) was measured by an autograph. A-GC showed a lower load than A-W-GC and A-W-CP-GC. The loads for A-W-GC and A-W-CP-GC were almost equal. The failure loads did not change significantly between 10 and 25 weeks for any of the materials. The interface was examined by Giemsa surface staining, contact micro-radiography, and SEM-EPMA. Giemsa surface staining and CMR revealed direct bonding between the materials and the bone for all the three materials. SEM-EPMA showed that Si and Mg content decreased, Ca content did not change, and P content increased at the reaction zone between all three glass ceramics and bone. This was observed at 10 weeks, as well as at 25 weeks, after implantation. The reaction zone was narrowest with A-GC, wider with A-W-GC, and widest with A-W-CP-GC.  相似文献   
34.
A serotype-specific polysaccharide antigen of Actinobacillus actinomycetemcomitans Y4 (serotype b) was extracted from whole cells by autoclaving. The extract was purified by chromatography on DEAE-Sephadex A-25 and Sephacryl S-300 columns. The purified polysaccharide antigen formed a single precipitin line with anti-type b serum but not with anti-type a serum and anti-type c serum. The antigen was composed of 43.9% L-rhamnose, 49.1% D-fucose, and a trace amount of fatty acid. Methylation analysis, Smith degradation, and optical rotation data showed that the antigen was a polymer consisting of a disaccharide repeating unit, ----3)-alpha-D-fucopyranosyl-(1----2)-beta-L-rhamnopyranosyl-(1----. In quantitative precipitin inhibition tests, D-fucose and L-rhamnose showed very low inhibition, but the partial hydrolysate of the purified antigen was an effective inhibitor, suggesting that the serotype b specific antiserum recognizes the larger oligosaccharide units.  相似文献   
35.
Angioscopic evaluation of coronary-artery thrombi in acute coronary syndromes.   总被引:12,自引:0,他引:12  
BACKGROUND. Disruption of an atherosclerotic plaque in a coronary artery followed by the formation of a thrombus is believed to be the cause of both unstable angina and acute myocardial infarction. Although thrombolytic therapy is efficacious in patients with acute myocardial infarction, for unknown reasons it is far less effective in patients with unstable angina. We postulated that there might be differences in the composition of the coronary-artery thrombi in unstable angina and acute myocardial infarction. METHODS. To investigate the appearance of coronary-artery thrombi, we performed percutaneous transluminal coronary angioscopy in 15 patients with unstable angina and 16 with acute myocardial infarction. Angioscopy was performed within 48 hours after an episode of pain at rest in the patients with unstable angina and within 8 hours of onset in those with acute myocardial infarction. RESULTS. Angioscopy revealed coronary thrombi in all but two patients (one in each group). Of the 29 patients with thrombi, those with unstable angina were frequently observed to have grayish-white thrombi (10 of 14, 71 percent), but none were seen in the 15 patients with acute myocardial infarction (P less than 0.01). By contrast, reddish thrombi were observed in all 15 patients with acute myocardial infarction who had thrombi, but in only 4 of the 14 patients with unstable angina and thrombi (P less than 0.01). As assessed by coronary angiography, occlusive thrombi occurred frequently in patients with acute myocardial infarction (13 of 16 patients) but were not seen in any of the 15 patients with unstable angina (P less than 0.01). CONCLUSIONS. Coronary-artery thrombi play an important part in the pathogenesis of unstable angina and acute myocardial infarction. However, the appearance of the thrombi is different in the two conditions, possibly reflecting differences in the composition of age of the thrombi or the presence or absence of blood flow in the artery. This difference may account for the contrasting results of thrombolytic therapy.  相似文献   
36.
Hyper beta-lipoproteinaemia in rats was produced by feeding a standard diet to which was added excess cholesterol and cholic acid, with or without olive oil, for 4, 8, and 12 weeks. The beta-lipoprotein percentage in serum lipoprotein electrophoresis and lipid contents in very low density lipoprotein and low density lipoprotein fractions in these rats were significantly higher than in the control rats fed the standard diet only. The percentage of foamy monocytes (FMs) to the total number of blood monocytes (BMs) from mononuclear leucocyte fractions and percentage of pulmonary foam cells (PFCs) to the number of alveolar macrophages (AMs) from bronchopulmonary lavage fluids in the rats increased with the extension of the feeding period and were significantly higher than those in the controls. An increase in the percentage of PFCs was closely correlated with that of FMs in the rats. FMs and PFCs had cytoplasmic fine vacuoles proved to be neutral lipid and cholesterol. Histologically, PFCs made an appearance in the lungs of all the rats as early as 4 weeks after the start of feeding. The degree of the PFCs' development increased as the feeding period lengthened. When latex particles were injected intravenously into rats at feeding week 4, the percentage of latex-ingested AMs to the number of AMs in the rats was significantly higher than that of the controls at 4 and 8 days post-injection. The percentage of latex-ingested PFCs to the number of latex-ingested AMs increased with the lapse of a day after injection and was significantly higher than that of the controls at 2, 4, and 8 days post-injection. The present findings suggest that the foamy transformation of BMs and their migration into the pulmonary alveoli may be a potential mechanism of the PFCs' development in rats with hyper beta-lipoproteinaemia.  相似文献   
37.
A case of an extrarenal Wilms' tumor arising in the retroperitoneal region of a 49-year-old male is reported. A review of the world literature indicates that the incidence of the tumor arising in the extrarenal region is extremely rare. A total of 14 cases have previously been reported, but the number of cases that occurred in adult patients is only 2. The clinical and pathologic features are briefly discussed.  相似文献   
38.
Clinical microbiology laboratories in Japan have not yet established standards for selecting the most appropriate antimicrobial agents for testing and reporting antimicrobial susceptibility that are comparable to the performance standards of the National Committee for Clinical Laboratory Standards(NCCLS) in the United States of America. Selection of the most appropriate antimicrobial agents for testing and reporting was discussed by a working group(WG) consisting of medical physicians, surgeons, pharmacists, medical technologists and medical microbiologists. The WG agreed on the following basic criteria for the selection of antimicrobial agents: 1) the agent should be useful when screening various resistant bacteria, 2) the agent should serve as a useful guide for physicians and residents when selecting antimicrobial agents, and 3) the agent should be useful for controlling nosocomial infections and resistant bacteria. Clinically isolated microorganisms were classified into 7 groups based on susceptibility to antimicrobial agents. These groups were Staphylococcus spp. or Enterococcus spp., Streptococcus spp. or Haemophilus spp., enterobacteriae, glucose non-fermenting gram positive rods(NFRs), anaerobic bacteria, fungi and mycobacterium. After considering clinical and bacteriological evidence, the WG decided on several antimicrobial agents for testing in clinical microbiology laboratories in Jichi Medical School Hospital. For the NFR group, these were Piperacillin(PIPC), ceftazidime(CAZ), cefepime, imipenem, amikacin and levofloxacin(LVFX). For the enterobacteriae group, these were Amplicillin(ABPC), PIPC, aztreonam, CAZ and LVFX. For the Staphylococcus spp. or Enterococcus spp. group, these were oxacillin, ABPC, vancomycin and gentamicin. We concluded that the most appropriate antimicrobial agent for testing and reporting must be economical and agreed upon at the hospital level, although the ultimate selection must be based on the available clinical and bacteriological evidence.  相似文献   
39.
Using transcranial magnetic stimulation (TMS), we examined whether sensory input from a finger affects activity of the ipsilateral primary motor cortex (M1) when human subjects hold a virtual object bimanually and whether this ipsilateral activation varies under different contexts. Subjects used both index fingers to hold two plates, which were subjected to unpredictable pulling loads from torque motors. Loads were delivered in a random sequence to either plate or concurrently to both, although the latter occurred most frequently. Finger forces vertical to the plates and surface electromyographs from the first dorsal interosseous muscles were recorded bilaterally during the task. TMS was sometimes applied over the finger area of the left M1 at variable times relative to load onset to examine cortical excitability. Strength of TMS was set around the active motor threshold of the right finger muscle while subjects waited for loading to the handheld plates. When one plate was singly loaded, the M1 contralateral to the loaded finger was activated, causing automatic force increases in the finger. In addition, the ipsilateral M1 was activated during such loading, associated with transient force increases in the contralateral nonloaded finger. Activations in the ipsilateral M1 were also observed during concurrent loading, when activations were stronger than those following single loading of the contralateral plate. Ipsilateral activations weakened when concurrent loading was less frequent. These results suggest interactions between bilateral sensorimotor cortices during bimanual coordinated movements, with strength varying by context.  相似文献   
40.
We have determined the entire nucleotide sequence of the human immunoglobulin kappa locus, comprising a total of 1,010,706 nucleotides. The 76 Vkappa genes found by a hybridization-based approach and their classification in 7 families were confirmed. A Vkappa orphon located near the locus was also sequenced. In addition, we identified 55 novel Vkappa relics and truncated pseudogenes, which establish 5 new families. Among these 132 Vkappa genes, 46 have open reading frames. According to the databases and the literature, 32 unique Vkappa genes and 5 identical gene pairs form VJ-joints, 27 unique genes and 4 gene pairs are transcribed, and 25 unique genes and 4 gene pairs produce functional proteins. The Vkappa gene locus contains a 360-kb inverted duplication, which harbors 118 Vkappa genes. A comparison of the duplicated Vkappa genes suggests positive selection on the complementarity-determining regions of the duplicated genes by point mutations. The entire duplication unit was divided into 13 blocks, each of which has its distinct nucleotide sequence identity to its duplication counterpart (98.1 - 99.9 %). An inversion-mediated mechanism is suggested to generate the high-homology blocks. Based on the homology blocks and the mutation rates, the inverted duplication is assumed to have taken place approximately 5 million years ago. An orphon Vkappa gene near the kappa locus and a cluster of five Vkappa orphons on chromosome 22 have no counterparts within the kappa locus. This suggests possible mechanisms of the transposition of orphon Vkappa genes.  相似文献   
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