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51.
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   
52.
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   
53.
A cDNA encoding a novel member of the small molecular weight GTP-binding protein (small G-protein) superfamily was cloned from rat spinal cord. The deduced amino acid sequence was highly homologous with those of so-far-known Rho proteins. Rho proteins were reported to alter many important cellular functions including formation of both actin stress fibers and focal adhesions. RNA blot hybridization and in situ hybridization analyses indicated that the novel small G-protein is expressed specifically in neurons in the brain and spinal cord and also in hepatic stellate cells. Based on the sequence similarity and neuron-specific expression in the brain, this protein was named RhoN. Unlike classical Rho proteins, RhoN was not susceptible to the ADP-ribosylation reaction by C3 botulinum toxin. Accordingly, RhoN seemed to be specifically involved in neuronal and hepatic functions as a C3 toxin-insensitive member of the Rho subfamily. Then, a mouse genomic DNA segment containing the RhoN gene was cloned. The locus was mapped on the mouse chromosome 11C-D. The sequence data showed that the protein-coding sequence for RhoN is divided by 4 introns, and that the defined 5 exons may encode intramolecular domains serving for different functions.  相似文献   
54.
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   
55.
Pancreaticogastrostomy (PG) has been reintroduced and employed occasionally as a useful alternative to pancreaticojejunostomy (PJ) after Whipple resection or pylorus-preserving pancreaticoduodenectomy (PPPD). Although the physiologic alteration in the stomach is important for the correlation between gastric and pancreatic functions, the actual intragastric pH profile after PG is still unclear. This study was conducted to investigate the physiologic changes in gastric pH and serum gastrin and secretin levels before and after PPPD reconstructed with PG (PPPD-PG) in humans. Twenty-four hour continuous intragastric pH and serum gastrin and secretin levels in the fasting state were examined in 25 patients who had undergone PPPD-PG. No peptic ulcer was detected after the operation. After PG, serum gastrin and secretin levels were unchanged. Twenty-four hour gastric pH monitoring revealed two distinct patterns during the nocturnal period before the operation: patients with acid-type secretion (n= 11) exhibited a persistent acid pH, whereas those with alkaline-type secretion (n= 14) had cyclic variations between an acid and an alkaline pH value. After PG, in both acid- and alkaline-type patients, median pH and percentages of time that the gastric pH was less than 4 (% pH < 4) and more than 6 (% pH > 6) did not change, and circadian pH patterns also remained unchanged. These results suggest that PPPD-PG has little influence on gastric acidity, and the neurohumoral relation between the stomach, duodenum, and pancreas is preserved after PG. Therefore, physiologically, PG can be recommended as a reconstructive procedure after PPPD.  相似文献   
56.
We examined the placentas of 12 patients in whom congenital cytomegalovirus CMV infection was suspected from serological and or pathological evaluation. Seven patients died including four intrauterine deaths and five survived. On histological examination, the characteristic inclusion bodies were detected in only three placentas, and villitis with plasma cell infiltration was seen in eight placentas. Immunohistochemistry using a specific antibody against CMV improved the sensitivity of CMV detection 10 cases were positive . With the polymerase chain reaction PCR following the extraction of DNA from formaldehyde-fixed placenta samples, CMV DNA was detected in seven cases. All 12 subjects were diagnosed with CMV infection by additional Southern blot analysis after the PCR. CMV DNA was also detected by an in situ hybridization method in all cases. With current molecular biological techniques the placenta can be reliably used for the diagnosis of congenital CMV infection.  相似文献   
57.
Background Deletions involving chromosome 9p21, on which the tumor suppressor genep16/MTS1 is located, have been noted in esophageal cancer. We investigated the relationship between the deletion of chromosome 9p21–22 and the clinical features of esophageal cancer. Methods We examined the loss of heterozygosity (LOH) on chromosome 9p21–22 in 56 esophageal cancers using polymerase chain reaction (PCR) analysis and 2 microsatellite markers (RPS6 and IFNA). Results In 18 out of 50 informative cases (36%), LOH had occurred at 1 or 2 loci on chromosome 9p21–22. We found no relationship between LOH on chromosome 9p21–22 and patient sex, age tumor length, location, histologic differentiation, depth of tumor invasion, the extent of lymph node metastasis, histologic stage, or curability. Among 35 patients without an absolute noncurative resection, the mean survival of 11 patients with LOH on chromosome 9p21–22 was 19.3 months, compared with 42.3 months for 24 patients with a normal allele; thus, the survival rate of those with LOH was significantly lower than that of patients without LOH on chromosome 9p21–22 (log-rank test;P=0.03). Conclusion These data suggest that LOH on chromosome 9p21–22, on which the cell-cycle regulatorp16/MTS1 gene is located, may be related to cancer development, and probably can serve as a clinical marker for evaluating a patient's prognosis.  相似文献   
58.
OBJECTIVE: To show the positional nystagmus in a patient who had suffered from benign paroxysmal positional vertigo (BPPV) that was thought to be caused by involvement of the anterior semicircular canal (ASCC) (A-BPPV). STUDY DESIGN: Retrospective case report. SETTING: City hospital. PATIENT: The present study reports a rare case of A-BPPV in a 41-year-old woman. CASE REPORT: The patient is 41-year-old woman who developed a positional vertigo after playing volleyball on March 22, 2005 and consulted our hospital the next day. When left Dix-Hallpike maneuver was performed, she showed a positional nystagmus of which fast phase direction of the torsional component was clockwise while that of the vertical component was downward. We plotted the slow phase eye velocity of the positional nystagmus during the left Dix-Hallpike maneuver on three-dimensional coordinates that showed the axis of the positional nystagmus to be perpendicular to the plane of the right ASCC. CONCLUSION: These results suggested that the patient was suffering from A-BPPV.  相似文献   
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