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61.
Trypanosoma brucei evades the immune system by switching between Variant Surface Glycoprotein (VSG) genes. The active VSG gene is transcribed in one of approximately 20 telomeric expression sites (ESs). It has been postulated that ES polymorphism plays a role in host adaptation. To gain more insight into ES architecture, we have determined the complete sequence of Bacterial Artificial Chromosomes (BACs) containing DNA from three ESs and their flanking regions. There was variation in the order and number of ES-associated genes (ESAGs). ESAGs 6 and 7, encoding transferrin receptor subunits, are the only ESAGs with functional copies in every ES that has been sequenced until now. A BAC clone containing the VO2 ES sequences comprised approximately half of a 330 kb 'intermediate' chromosome. The extensive similarity between this intermediate chromosome and the left telomere of T. brucei 927 chromosome I, suggests that this previously uncharacterised intermediate size class of chromosomes could have arisen from breakage of megabase chromosomes. Unexpected conservation of sequences, including pseudogenes, indicates that the multiple ESs could have arisen through a relatively recent amplification of a single ES.  相似文献   
62.
Using 12 healthy male subjects, the dynamic motor ability of individual fingers was investigated under four different finger tapping conditions. These were: maximum speed tapping with one finger (single-finger tapping), alternate movement of two fingers (double-finger tapping), double-finger tapping in an unsupported condition, and submaximum constant speed tapping with one finger in a passive manner. Key-contact forces for all fingers and the movement velocity of the tapping finger were monitored. With the exception of the unsupported condition, non-tapping fingers were maintained in contact with designated keys during the tapping tasks. It was found that the index finger attained the fastest cadence and greatest movement velocity, followed by the middle, little and ring fingers, respectively. Subjective assessment of rank order of "difficulty" of tapping by the subjects was highly correlated with tapping cadence. Thus dynamic motor function, as indicated by rapid, repetitive movement, differs among the individual fingers. Parallel changes were observed in the key-contact force of the neighboring non-tapping fingers during tapping. The range of the non-tapping finger forces was largest during tapping by the ring finger. A similar trend was found for passive tapping, during which the magnitude of key-contact force was less than one-third of that observed during active tapping. The lower cadence achieved by the ring finger may be attributed more to a lack of independence at the level of voluntary neuromuscular control, than to innate mechanical interaction with the other fingers. Tapping cadence of each finger was lower for the double-finger mode than for the single-finger mode. The magnitude of the observed decrease in cadence during double-finger tapping was, on the other hand, strongly dependent on finger-combination. The decrease was smallest for the index-middle finger-combination, and greatest for the ring-little finger-combination. Compatibilities with other fingers can play an essential role in the dynamic motor function of individual fingers. During the unsupported task, in which interactions were diminished by allowing all fingers to move freely, tapping cadence increased markedly. Therefore, the lower cadences observed in specific finger-combinations may be partly attributed to anatomical and neural interdigit interactions.  相似文献   
63.
In the cirrhotic and precirrhotic liver, there may be small foci with increased cellularity and amphophilic cytoplasm. These are microscopic lesions that do not form macroscopically detectable nodules, which differ from the macroscopically apparent nodules of dysplastic nodules. In the present study, we assessed the proliferating activity of 12 hyperplastic foci in 11 patients with cirrhosis or chronic hepatitis, by staining for agyrophilic nucleolar organizing regions (AgNOR). The mean AgNOR count per nucleus in the hyperplastic foci ranged from 0.96 to 1.36 (mean, 1.13; SD 0.12), and from 0.81 to 1.06 (mean, 0.94; SD 0.08) in the controls. The AgNOR count In the hyperplastic foci was significantly higher than that In the controls (P> 30.01). Small hyperplastic foci show Increased proliferative activity. Further study on these foci is required to clarify their relation to hepatocarcinogenesis.  相似文献   
64.
Silver‐Russell syndrome (SRS) is characterized by prenatal and postnatal growth retardation with morphologic anomalies. Maternal uniparental disomy 7 has been reported in some SRS patients. PEG1/MEST is an imprinted gene on chromosome 7q32 that is expressed only from the paternal allele and is a candidate gene for SRS. To clarify its biological function and role in SRS, we screened PEG1/MEST abnormalities in 15 SRS patients from various standpoints. In the lymphocytes of SRS patients, no aberrant expression patterns of two splice variants (α and β) of PEG1/MEST were detected when they were compared with normal samples. Direct sequence analysis failed to detect any mutations in the PEG1/MEST α coding region, and there were no significant mutations in the 5′‐flanking upstream region containing the predicted promoter and the highly conserved human/mouse genomic region. Differential methylation patterns of the CpG island for PEG1/MEST α were normally maintained and resulted in the same pattern as in the normal control, suggesting that there was no loss of imprinting. These findings suggest that PEG1/MEST can be excluded as a major determinant of SRS. © 2001 Wiley‐Liss, Inc.  相似文献   
65.
The p16-cyclinD1/CDK4-pRb pathway (RB pathway) and p14ARF-MDM2-p53 pathway (p53 pathway) work at the G1-S checkpoint, and the ATM-chk2-CDC25-cyclinB1/cdk1 pathway works at the G2-M checkpoint. The disruption of these pathways is thought to be related to the prognosis of human cancer. In this study, we analyzed the status of these pathways in 107 epithelial ovarian cancer (EOC) patients by immunohistochemistry and evaluated the relationship of these results with chemotherapy response and the prognosis. Altered RB, p53, and G2 pathways were detected in 50.5% (54/107), 51.4% (55/107), and 33.6% (36/107) of cases, respectively. The overall survival (OS) of 77.3% for patients with a normal RB pathway was significantly higher than the OS of 50.0% for patients with an altered RB pathway (by Kaplan-Meier analysis, P = 0.0021). The OS of 66.2% for patients with a normal G2 pathway was significantly higher than the OS of 58.3% for patients with an altered G2 pathway (P = 0.0416). However, the status of the p53 pathway was not related to OS. By univariate and multivariate analyses, advanced stage, high histological grade, altered RB pathway, and altered G2 pathway were significant predictors of poor OS. However, there was no significant relationship between pathway status and chemotherapy response. The status of the RB pathway and of the G2 pathway were independent prognostic factors of EOC.  相似文献   
66.
Despite a multitude of reports on the classification and distribution of anterior pituitary cells, no previous study has attempted to obtain the three-dimensional (3D) and computer-graphic distribution pattern of each cell type in the whole pituitary. Therefore, we mapped the anterior pituitary cells of the house musk shrew ( Suncus murinus) and found a distinct cellular distribution pattern. Serial horizontal sections of whole shrew pituitaries were stained immunohistochemically for prolactin (PRL), growth hormone (GH), and adrenocorticotropic hormone (ACTH) cells. The contours of positive cells and the anterior, intermediate, and posterior lobes in each section were digitized for 3D visualization by a volume rendering method. The reconstructed images and virtual frontal and sagittal slices were examined in detail. On the 3D reconstructed images, the PRL and GH cells had similar distribution patterns, although the former were concentrated in the dorsolateral and ventrocentral portions, and the latter in the dorsocentral portions of the anterior lobe. On both sides of the pituitary stalk, there lay portions that were conspicuous by scarcity of PRL and GH cells. ACTH cells were widely scattered throughout the whole anterior lobe, but they were very few in the above portions and the dorsocentral portions where GH cells were concentrated. No sex difference in the distribution patterns of each cell type was observed. However, PRL cells in females were more numerous than in males, whereas the opposite was true for GH and ACTH cells. We discuss the relationship between the formation of the spatial distribution patterns and anterior pituitary ontogeny.  相似文献   
67.
Selective effects of Lipiodolized antitumor agents   总被引:4,自引:0,他引:4  
Lipiodol Ultra-Fluid (Lipiodol) remains selectively in the tumor for an extended time when applied through arteries feeding the tumor. Although lipophilic antitumor drugs are selective when combined with Lipiodol, wide application of common hydrophilic agents is limited, as these compounds are insoluble in oil. We propose "Lipiodolization" of water-soluble agents using as an intermediate Urografin, a water-soluble contrast medium. Thirteen patients with primary hepatocellular carcinoma were treated with this Lipiodol-Urografin system containing antitumor agents. Marked decrease in serum alpha-fetoprotein (AFP) levels, decrease in tumor size in the hepatic imaging, and histologic studies of the resected specimen revealed this mode of therapy to be effective in 10 of 13 patients (77%) with hepatocellular carcinoma. Lipiodolization of antitumor agents is a new approach to selective cancer chemotherapy.  相似文献   
68.
ObjectivesWe aimed to evaluate the effect of frailty on health-related quality-of-life (HRQOL) and lower urinary symptoms (LUTS) following robot-assisted radical prostatectomy (RARP) in patients with prostate cancer (CaP).Materials and MethodsWe longitudinally evaluated geriatric 8 (G8), HRQOL, and LUTS for 12 months in 118 patients with RARP from January 2017 to April 2020. Patients were divided into frail (G8 ≤14) and nonfrail (G8 >14) groups. We compared the effect of frailty on HRQOL and LUTS between the frail and nonfrail groups before and 12 months after RARP.ResultsThe median age of patients was 68 years. The number of patients in the frail and nonfrail groups were 41 and 77, respectively. No significant difference in patients’ background was observed between the groups, except for the presence of cardiovascular disease (22% vs. 7.8%, P = 0.041). There was no significant difference in HRQOLs and LUTS between the groups at baseline. Similarly, HRQOLs, LUTS, and pad-free continence rates were not significantly different between the groups at 12 months after RARP. In the nonfrail group, LUTS at 12 months following RARP significantly improved compared to those at the baseline, but it did not significantly improve in the frail group. Multivariable logistic regression analysis demonstrated that frailty was not significantly associated with LUTS worsening.ConclusionsFrailty was not significantly associated with the worsening of HRQOL, LUTS, and pad-free continence rates in patients treated with RARP.  相似文献   
69.
Purpose: Membrane cofactor protein (MCP), CD46, whose primary function is to protect host cells from homologous complement, has been presumed to serve as a sperm adhesion molecule for oocytes. The purpose of this study was to clarify the relationship between the properties of MCP expressed on epididymal sperm and their fertilizing ability in a recently developed strategy for assisted reproduction. Methods: We collected ejaculated sperm from normal subjects and epididymal sperm from vasectomized subjects and patients with congenital absence of the vas deferens. Western blotting and cofactor activity assay were performed to investigated the structural and functional properties of MCP. Results: Epididymal spermatozoa which showed a reduced fertilizing ability tended to react poorly with antibodies against MCP and also showed low cofactor activity, indicating weak complement regulatory activity compared to that of ejaculated spermatozoa. Conclusions: MCP is sufficiently expressed in ejaculated sperm in men with a normally developed epididymis but is diminished in epididymal sperm from men with congenital or acquired obstruction of the vas deferens.  相似文献   
70.

Purpose

To determine the extent of enhanced blockade by the combined use of epidural fentanyl and mepivacaine. We compared the onset of hypoalgesia, analgesia and the threshold of pressure pain.

Methods

Thirty patients were randomly divided into three groups. The fentanyl group received 10 ml saline containing 0.1 mg fentanyl, mepivacaine group received 10 ml mepivacaine 1% and a mixed group received 10 ml mepivacaine 1% with 0.1 mg fentanyl. All solutions, without epinephrine, were injected through an epidural catheter at T5–6 to T6–7. The change in sensation, loss of pin-prick and pain threshold sensation, measured by pressure algometer, were assessed at 2.5-min intervals for 15 min at the T4 dermatome. Spread of analgesia was determined at 15 min.

Results

Loss of pinprick was more rapid in the mixed, 11.0 ± 2.7 (SD) min, than in the mepivacaine group, 15.0 ± 2.9 min, (P < 0.05), although there was no difference in change of sensation. Pressure pain threshold increased with time in the mepivacaine (P < 0.05) and mixed (P < 0.05) groups. It was higher in the mixed than in the fentanyl and mepivacaine groups at 5, 7.5 and 10 min (P < 0.05). The lower level of analgesia was lower in the mixed than in the mepivacaine groups (P < 0.05). Blood pressure was unchanged in the three groups, but heart rate decreased at 7.5, 10, 12.5, and 15 min in the mepivacaine and mixed groups (P < 0.05).

Conclusions

The addition of fentanyl to mepivacaine accelerates the onset of analgesia and enhances the analgesic effect of epidural block.  相似文献   
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