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51.
A middle meningeal artery arising from the internal carotid artery was found in the right half of the head of an 85-year-old male cadaver during student dissection practice. It arose from the lateral aspect of the internal carotid artery in the carotid canal, arrived at the foramen lacerum after running forward. It then ran backward under the trigeminal ganglion and took the usual course after passing its posterior margin. On one hand, the maxillary artery did not issue the middle meningeal artery, gave off only a small twig supplying the lateral pterygoid muscle at the corresponding position. It was corroborated by the fact that the foramen spinosum was absent in this example. During usual development, the middle meningeal artery primarily springs from the supraorbital branch of the stapedial artery that arises from the dorsal part of the second branchial artery. Later, by the formation of the external carotid artery connecting with the common trunk of the infraorbital and mandibular branches (maxillomandibular division) of the stapedial artery and by the atrophy of the proximal part of it, the middle meningeal artery is finally supplied by the external carotid artery. But in this example, it is supposed that the middle meningeal artery arose from a more distal position of the internal carotid artery owing to the persistence of the anastomosis between the dorsal part of the first branchial artery and the supraorbital branch and the interruption of the connection between the supraorbital branch and maxillomandibular division of the stapedial artery.  相似文献   
52.
DNA damage triggers the activation of checkpoints that delay cell cycle progression to allow for DNA repair. Loss of G2 checkpoints provides a growth advantage for tumor cells undergoing aberrant mitosis. However, the precise mechanisms of G2 checkpoints acting in gastric cancer are unknown. Here, we analyzed the G2 checkpoint function in two gastric cancer cells, MKN-28 cells containing a mutant p53 gene and MKN-45 cells which have wild-type p53. Two agents damaging DNA, camptothecin (CPT) or ultraviolet light (UV), were utilized to trigger a G2 phase cell cycle checkpoint response in these tumor cells. Both CPT and UV inhibited the growth of MKN-45 cells, whereas they did not affect the growth of MKN-28 cells. CPT induced cell cycle arrest at the G2/M phase and enhanced the expression of human RAD9 (hRAD9) in MKN-45 cells. In addition, hRAD9 showed perinuclear staining and similar localization with Bcl-2 in MKN-45 cells but not in MKN-28 cells after having applied CPT or UV light. These results suggest that besides p53 activity, the induction of hRAD9 is required for G2/M checkpoint signal transduction in gastric cancer cells.  相似文献   
53.
BACKGROUND AND METHODS: Type 1 diabetes mellitus is now classified as autoimmune (type 1A) or idiopathic (type 1B), but little is known about the latter. We classified 56 consecutive Japanese adults with type 1 diabetes according to the presence or absence of glutamic acid decarboxylase antibodies (their presence is a marker of autoimmunity) and compared their clinical, serologic, and pathological characteristics. RESULTS: We divided the patients into three groups: 36 patients with positive tests for serum glutamic acid decarboxylase autoantibodies, 9 with negative tests for serum glutamic acid decarboxylase antibodies and glycosylated hemoglobin values higher than 11.5 percent, and 11 with negative tests for serum glutamic acid decarboxylase antibodies and glycosylated hemoglobin values lower than 8.5 percent. In comparison with the first two groups, the third group had a shorter mean duration of symptoms of hyperglycemia (4.0 days), a higher mean plasma glucose concentration (773 mg per deciliter [43 mmol per liter]) in spite of lower glycosylated hemoglobin values, diminished urinary excretion of C peptide, a more severe metabolic disorder (with ketoacidosis), higher serum pancreatic enzyme concentrations, and an absence of islet-cell, IA-2, and insulin antibodies. Immunohistologic studies of pancreatic-biopsy specimens from three patients with negative tests for glutamic acid decarboxylase autoantibodies and low glycosylated hemoglobin values revealed T-lymphocyte-predominant infiltrates in the exocrine pancreas but no insulitis and no evidence of acute or chronic pancreatitis. CONCLUSIONS: Some patients with idiopathic type 1 diabetes have a nonautoimmune, fulminant disorder characterized by the absence of insulitis and of diabetes-related antibodies, a remarkably abrupt onset, and high serum pancreatic enzyme concentrations.  相似文献   
54.
The role of a telomerase assay in the recognition of Sertoli cell-only syndrome with testicular foci of haploid cells was evaluated. Men with Sertoli cell-only syndrome (n = 23) were given a new diagnostic testicular biopsy. Part of the biopsy was stained and the remainder was processed for the quantitative telomerase assay. After 3-13 months, a therapeutic testicular biopsy was performed. This material was minced and then examined using confocal laser scanning microscopy and fluorescent in-situ hybridization. Histology of diagnostic testicular biopsy material confirmed the diagnosis of Sertoli cell-only syndrome in all the participants. All seven men with a telomerase assay value in their diagnostic testicular biopsy of >42 total product generated (TPG) U/microg protein had haploid cells (i.e. spermatozoa and/or spermatids) in their therapeutic testicular biopsy. Among participants with telomerase assay values <42 TPG U/microg protein, only one man had haploid cells in his therapeutic testicular biopsy. Thus, telomerase assay values >42 TPG U/microg protein in the diagnostic biopsy identified 87.5% of the Sertoli cell-only syndrome men with haploid cells in their therapeutic testicular biopsy. Significantly higher values of the telomerase assay were found in men with testicular foci of haploid cells than in men without these foci. The use of a quantitative telomerase assay biopsy appears to be important for identifying those men with Sertoli cell-only syndrome who have foci of haploid cells and can be candidates for assisted reproduction techniques.  相似文献   
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Molecular defects of TNFRSF1A was investigated in members of a family presenting with typical phenotypes of tumor necrosis factor receptor-associated periodic syndrome (TRAPS) and in patients with the autoimmune disorders, systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). Genomic DNA from the members of a family with typical TRAPS, as well as from 100 patients with SLE, 100 patients with RA and 100 healthy individuals, was studied for mutations in exons 2, 3 and 4 of the TNFRSF1A gene. All individuals were Japanese. Three novel missense mutations were identified in the TNFRSF1A. The C70G mutation was identified in family members with typical TRAPS, which was the second case in eastern Asian population. In addition, the T61I and R104Q mutations were each identified in 2 of the 100 SLE patients. The T61I mutation was identified in one of the 100 healthy individuals. No mutations were identified in the 100 RA patients. Functional analysis revealed that PMA-induced shedding of TNFRSF1A from PBMCs was impaired in a patient carrying T61I. A larger scale of study will clarify whether these two mutations, T61I and R104Q, are associated with chronic inflammatory disorders, such as SLE, or not.  相似文献   
58.
The full-length cDNA corresponding to the mRNA for the hemagglutinin (H) protein of the Yamagata-1 strain of the subacute sclerosing panencephalitis (SSPE) virus was cloned and the nucleotide sequence was determined. The mRNA corresponding to the H protein was composed of 1952 nucleotides and contained a single large open reading frame, which encoded 620 amino acids with a predicted molecular weight of 69,723. This cDNA clone expressed the H protein in Cos 7 cells, and the transfected cells showed hemadsorption. The nucleotide and amino-acid sequence homology with the Edmonston strain of MV were 98.0% and 96.6%, respectively. The deduced amino acid sequence had a single hydrophobic domain near the N-terminus that was long enough to serve as an anchor in the membrane. Five potential glycosylation sites were found on the H protein at identical positions as in the H protein of MV. Cysteine and proline were located at almost identical positions as those of the H protein of MV. In addition, monoclonal antibody study revealed that three epitopes, including the domains that were involved in the biological activities of the H protein of MV, were conserved on the Yamagata-1 strain. These results suggested that the H protein of the Yamagata-1 strain of defective SSPE virus is structurally and functionally similar to that of the Edmonston strain of MV.  相似文献   
59.
The nucleotide sequence of a cloned cDNA corresponding to the P+M dicistronic mRNA of a subacute sclerosing panencephalitis (SSPE) virus was determined and compared with data of measles virus (MV). The dicistronic mRNA of the SSPE virus consisted of the 3 proximal 626 nucleotides of P mRNA, intercistronic trinucleotides, a full length of M mRNA, and 75 poly A nucleotides. The part encoding the P protein had a high homology to MV, except at the noncoding region. The terminating consensus sequence of the P gene and the intercistronic trinucleotides of the SSPE virus were CTAC(A)6 and CCT; in MV they are TTAT(A)6 and CTT, respectively. In the M gene, the starting consensus sequence was exactly the same as MV, but at the 5 proximal end, one third of this gene was different: The first ATG codon of the MV M gene signaling opening of the reading frame was changed to ACG in the SSPE virus and one long open reading frame started from the third ATG codon. The stop codon (TAG) of the MV M gene was also changed to CAG in the SSPE virus. Thus, the deduced SSPE-virus M protein lacked 50 amino acids at the amino terminal and had 15 extra amino acids at the carboxyl end when compared with the MV M protein.  相似文献   
60.
Selective cerebral perfusion (SCP) is a better method than hypothermic circulatory arrest for brain protection in aortic arch surgery because of fewer time limitations; however; it is more troublesome during surgery. We developed a new catheter for SCP, the SP Stud catheter, with a rib-surface balloon to reduce slipping to eliminate the need for snaring or clamping. To evaluate the slipping resistance of the new catheter, we compared it with two different balloon catheters; a Foley balloon catheter with a smooth-surface balloon as long as the SP Stud catheter, and a Retro-TH catheter with a smooth-surface balloon of discoid shape half as long as the SP Stud catheter. The “draw-strength”, which refers to the slipping resistance, was measured in 20 autopsy carotid arteries in the three groups. The average draw-strengths of SP Stud catheter, foley balloon catheter, and Retro-TH catheter were 92.3±4.0, 20.8 ±1.5, and 17.9±0.8g, respectively, in sclerotic carotid arteries. The SP Stud catheter demonstrated approximately four times more resistance to slipping than the Foley balloon or Retro-TH catheters. The SP Stud catheter demonstrated a higher slipping resistance than conventional catheters, which may allow selective cerebral perfusion without snaring or clamping the carotid arteries, minimize the change of cerebral embolism, and clear the operative field.  相似文献   
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