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101.
The genomic RNA of the Japanese encephalitis virus (JEV) Beijing-1 strain was reversely transcribed and the synthesized cDNA was molecularly cloned. Six continuous cDNA clones that cover the entire virus genome were established and sequenced to determine the complete nucleotide sequence of the JEV RNA. The precise genomic size was estimated as 10,965 bases long. With flanking 95 bases at the 5 and 583 bases at the 3 non-coding regions, one long open reading frame (ORF) was revealed encoding a virus polyprotein with 3,429 amino acid residues. Because of sequence homologies observed between JEV and other flaviviruses, the genome organization of JEV appears to be identical with other flaviviruses. Genetic variation detected among flavivirus genomes is consistent with the established serological relatedness between JEV and other members of flaviviruses. The secondary structure of the JEV genome is deduced and discussed concerning its involvement in genome replication.  相似文献   
102.
A 66-year-old male with osteoclast-like giant cell tumor of the liver that arose in the non-cirrhotlc liver is presented. The liver tests were almost normal, and plasma levels of alpha-fetoprotein and carcinoembryonic antigen were within normal limits. The findings of liver scan by 99mTc phytate, celiac angiography, and CT scans are described for the first time for this rare neoplasm, showing a large, unresectable liver tumor. Histologically, the tumor mainly consisted of osteoclast-like giant cells and mononuclear cells, which were focally arranged in a vaguely trabecular pattern and sarcomatous pattern. By an electromicroscopic study, however, no definitive evidence was obtained whether it arose from epithelial cells or nonepithellal cells. Various clinicopathological features were described and compared with previously reported cases including two cases arising in the liver.  相似文献   
103.
Two rare variants of HLA-A locus antigens, tentatively called HLA-A2K and HLA-A9HH, were serologically identified in the Japanese population. A2K and A9HH showed short reaction patterns of a series of anti-A2 and anti-A9 sera, respectively. The latter variant also reacted with some anti-A2 sera. Nucleotide sequences of full-length cDNAs for A2K and A9HH were determined. The results revealed that both antigens are encoded by previously undescribed alleles. The nucleotide sequence of the allele for A2K was identical to that of A*0207 except for a single nucleotide difference in exon 3. The nucleotide sequence of the allele for A9HH was identical to that of A*2402 except for two nucleotides in exon 2. These two nucleotides are shared by all the reported A2 alleles. These sequencing results the allele for A9HH were consistent with the serological cross-reactivity of A9HH with some anti-A2 sera.  相似文献   
104.
We investigated the cutaneous blood supply in the gluteal and perineal regions of 35 donated cadavers to provide an anatomical basis for reliable vulvo-vaginal reconstruction using a skin flap such as the so-called gluteal fold flap. The cutaneous areas along the gluteal cleft and sulcus were likely to be supplied by 3 routes: 1) the internal pudendal artery (IPA), especially its first cutaneous branch; 2) perforators running through the gluteus maximus muscle and arising from the inferior gluteal artery (IGA); and 3) a non-perforator running around and inferior to the ischial tuberosity and originating from the IGA. Route 1 supplied the skin along the gluteal cleft, route 2 the gluteal fold (i.e., a bulky skin fold along the upper edge of the gluteal sulcus), and route 3, just along the gluteal sulcus. In those 3 routes, we noted the consistent morphology of the thick and long, first cutaneous branch of the IPA. The first arterial branch, 1.5 mm in diameter at its origin on average (ranging from 0.7-2.6 mm), usually originated from the IPA under the cover of or at the inferomedial or distal side of the sacrotuberous ligament (almost always less than 20 mm from the inferomedial margin of the ligament). The branch ran superomedially toward the coccyx or ran medially in the ischiorectal fat. It accompanied the vein and nerve at its distal (peripheral) course although the nerve often ran independently at its proxomal course near the ligament. Therefore, the first branch of the IPA seems to provide a reliable pedicle using the skin along the gluteal cleft whether the incision for approach is conducted along the gluteal sulcus or not. However, if the gluteus maximus muscle extended much inferomedially, the pedicle would be very short. In this case, preparation of the pedicle seems to be necessary along the arterial course under the cover of the muscle.  相似文献   
105.
Black fungi are a group of fungi that are characterized by the development of a pale brown to black color in the cell walls of their vegetative cells, conidia, or both. A mycotic infection caused by a member of black fungi can be subdivided into three clinical entities: phaeohyphomycosis, chromoblastomycosis, and mycetoma. Phaeohyphomycosis is distinguished from mycetoma by the absence of grain (organized, interwoven mycelial aggregates) formation, and from chromoblastomycosis by the absence of sclerotic bodies (thick-walled muriform cells). Phaeohyphomycosis is a rare disease and has been sporadically reported. In the present report, phaeohyphomycosis of the right thumb of a 72-year-old man was presented. A precipitating trauma of two months earlier at the site was recalled. A solitary mass, 10 mm in diameter, was gradually formed in the palm side of the distal right thumb and finally resected. Histological examination disclosed a solitary granulomatous lesion surrounded by an incomplete fibrous capsule. The lesion mainly involved subcutaneous tissue and was composed of multiple pyogranulomas. Pigmented branched septate hyphae and yeast-like cells were sparsely found in the periphery of the abscess and within histiocytic cells of the granulomas. No sclerotic cells were detected. When pigmentation of black fungi in tissue is as faint as in the present case, Fontana-Masson staining is useful to accentuate the presence of melanin-like pigment of fungal cell walls.  相似文献   
106.
Morphogenesis in the developing embryo takes place in three dimensions, and in addition, the dimension of time is another important factor in development. Therefore, the presentation of sequential morphological changes occurring in the embryo (4D visualization) is essential for understanding the complex morphogenetic events and the underlying mechanisms. Until recently, 3D visualization of embryonic structures was possible only by reconstruction from serial histological sections, which was tedious and time-consuming. During the past two decades, 3D imaging techniques have made significant advances thanks to the progress in imaging and computer technologies, computer graphics, and other related techniques. Such novel tools have enabled precise visualization of the 3D topology of embryonic structures and to demonstrate spatiotemporal 4D sequences of organogenesis. Here, we describe a project in which staged human embryos are imaged by the magnetic resonance (MR) microscope, and 3D images of embryos and their organs at each developmental stage were reconstructed based on the MR data, with the aid of computer graphics techniques. On the basis of the 3D models of staged human embryos, we constructed a data set of 3D images of human embryos and made movies to illustrate the sequential process of human morphogenesis. Furthermore, a computer-based self-learning program of human embryology is being developed for educational purposes, using the photographs, histological sections, MR images, and 3D models of staged human embryos.  相似文献   
107.
Changes in correlation dimensions of the electroencephalogram (EEG) were examined in three different tasks. These three tasks differed from each other with respect to the number of procedures. In the present experiment, left-hand movement and mental arithmetic were controlled, respectively, during an auditory linguistic task. Subjects were 13 healthy right-handed males. EEG signals from eight electrode sites were analyzed and the correlation dimensions were obtained. In addition, the relative power was obtained for the alpha band. An increase in the number of procedures yielded high dimensionality on the occipital EEG. In contrast, left-hand movement had no significant effect on EEG dimensions over the motor area. The relative power of the alpha band was seen to decrease in all channels as the number of procedures increased. The fact that changes in EEG dimensions did not necessarily exhibit a simple correspondence to changes in alpha wave activity was also discussed.  相似文献   
108.
 Morphometric analyses of the immunohistochemical expression of the Clara cell secretory 10-kDa protein (CC10) and surfactant apoproteins A and B (SP-A and -B) were carried out on the developing bronchi and bronchioles of human fetuses and neonates. We analysed the ratio of the number of CC10-positive cells per subepithelial length of the bronchial or bronchiolar basement membrane and found that both the bronchial and the bronchiolar population of CC10-positive cells was significantly higher than that of either SP-A or SP-B. In addition, CC10 was found to be distributed mainly in the bronchiole. CC10-positive cells began to be recognized in the late pseudoglandular phase (15 weeks of gestation) and thereafter gradually increased in the canalicular and terminal sac phases, which correspond to the active development period of the acini or peripheral airways. The earliest expression of SP-A was also noted at 15 weeks of gestation, but its positive epithelial cells were present mainly in the larger bronchi. Double immunohistochemical staining for CC10 and SP-A revealed that the CC10-positive cells lining both the bronchi and bronchioles were different from the SP-A-positive cells. This finding suggests that CC10-positive cells are functionally and developmentally heterogeneous in both fetal and neonatal lungs in humans Received: 22 May 1997 / Accepted: 21 July 1997  相似文献   
109.
A 75-year-old woman with lung adenocarcinoma in whom autopsy revealed metastasis to microfollicular adenoma of the thyroid is described. A thyroid tumor specimen from this patient was initially interpreted as representing primary encapsulated follicular carcinoma of the thyroid associated with a component of poorly differentiated carcinoma of follicular cell origin. The widespread involvement of the lungs and other sites was also interpreted as metastases from the poorly differentiated carcinoma component within the encapsulated follicular carcinoma of the thyroid. Subsequent meticulous histologic examination revealed that the thyroid tumor was a microfollicular adenoma, and that the component of poorly differentiated carcinoma within it was the same as the lung carcinoma. Immunohistochemical investigation revealed that the poorly differentiated carcinoma cells within the thyroid tumor were stained positively with polyclonal and monoclonal antibodies against carcinoembryonic antigen (CEA) and negative for thyroglobulin and calcitonin. The carcinoma cells from the lungs and other sites also showed positive staining for CEA. These findings support the view that the component of poorly differentiated carcinoma was a metastatic lesion from the primary lung carcinoma to the microfollicular adenoma of the thyroid. The present study emphasizes that attention should be directed to thyroid metastasis, even if it is within a thyroid primary neoplasm.  相似文献   
110.
A case of bronchial plasmacytoma occurring in a 57- year-old housewife is reported. She had had the productive cough and the "abnormal shadow" in the right lower lobe for three years before admission. On bronchocopy, a tumor was found in the right main bronchus, large enough to obstruct the air way. The tumor was resected through rigid bronchoscope. Histological impression was "plasmacytoma with local amyloid deposit." M-protein was never detected in the serum or urine. Applying the immunoperoxidase technique for the paraffin section, the plasma cells were found to contain only a single type of immunoglobulin, Ig G-L. The differential diagnosis between plasmacytoma and plasma cell granuloma was made, and plasmacytoma was considered to be one type of extranodal malignant lymphoma.  相似文献   
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