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991.
The aim of this study was to assess the quality of colonoscopic procedures in our endoscopy unit with the goal of improving performance. METHODS: We prospectively audited 500 consecutive colonoscopic procedures and assessed sixty-two process or outcome indicators for each procedure. RESULTS: Most of the measured indicators were within standard limits: cecal intubation rate (92%), inadequate bowel preparations (24%), inappropriate procedures (9.7%), normal procedures (54%), yield for neoplasia (32%), morbidity (0.4%), and overall patient satisfaction (95.8%). Some indicators were outside standard limits suggesting our practices should be modified: endoscopy withdrawal time less than 6 minutes (78%), forceps removal of polyps (31%), resected polyps not recovered for pathological examination (12%), adenomas with villous elements (22%), patients unsatisfied because of time spent waiting for the procedure (19%), patients unsatisfied because of inadequate explanations (10%). There was no standard for a few indicators: patient discomfort (6.9%), diagnostic success (89%), therapeutic success (92%). Three new indicators were proposed: proportion of patients aged<50 years, number of normal colonoscopic procedures to perform to detect one advanced adenoma or cancer, and proportion of colonoscopic procedures causing discomfort. The diagnostic yield of colonoscopy was dependent on age, gender, indication and appropriateness of indication but not on the prescriber. CONCLUSION: This audit allowed us to evaluate our endoscopic practices and to detect certain shortcomings and deviations from standards. It enabled us to change some of our practices with the goal of improving the quality of our colonoscopic procedures.  相似文献   
992.
Background/Aims: We compared the efficacy and safety of the combined therapy of daily interferon α-2b and ribavirin with those of interferon α-2b three times per week alone or in combination with ribavirin in non-responder patients with hepatitis C virus (HCV) infection.Methods: A total of 376 patients were randomly assigned to receive interferon α-2b (6 MU three times per week for 24 weeks followed by 3 MU three times per week for 24 weeks) alone (group A) or in combination with ribavirin for 48 weeks (group B), or daily interferon α-2b (3 MU per day for 24 weeks followed by 3 MU three times per week for 24 weeks) and ribavirin (group C).Results: After 24 weeks of therapy, HCV RNA was undetectable in 11.7, 24.0, and 37.8% for groups A, B, and C, respectively. Sustained virological response was more frequent in patients who received combination therapy with three times weekly interferon (20.9%) or daily interferon (26.0%) than in patients who received interferon alone (5.8%) (P<0.001). The predictive HCV parameters for sustained response were a low viral load on day 7 and a negative HCV RNA on week 12.Conclusions: In conclusion, in non-responder patients with chronic hepatitis C, virological response with daily interferon and ribavirin, compared to interferon monotherapy, was significantly improved during treatment, although sustained virological response was similar for both combination therapies with ribavirin and three times a week or daily interferon.  相似文献   
993.
ActA, a surface protein of Listeria monocytogenes, is able to induce continuous actin polymerization at the rear of the bacterium, in the cytosol of the infected cells. Its N-terminal domain is sufficient to induce actin tail formation and movement. Here, we demonstrate, using the yeast two-hybrid system, that the N-terminal domain of ActA may form homodimers. By using chemical cross-linking to explore the possibility that ActA could be a multimer on the surface of the bacteria, we show that ActA is a dimer. Cross-linking experiments on various L. monocytogenes strains expressing different ActA variants demonstrated that the region spanning amino acids 97–126, and previously identified as critical for actin tail formation, is also critical for dimer formation. A model of actin polymerization by L. monocytogenes, involving the ActA dimer, is presented.  相似文献   
994.
Purpose: The objectives of this study were to (1) describe the sociodemographic profile of service dog users, their physical disabilities, main occupations, living environment, and use of technical aids in daily life and (2) evaluate the impact of service dogs on wheelchair travel and picking up objects. Method: Sociodemographic and clinical data were collected and various mobility tests were conducted in the service dog users’ home environment (n?=?199). Results: The service dog users had injuries to the central or peripheral nervous system (55%), spinal cord (33%), or musculoskeletal or orthopedic system (12%). In the wheelchair travel on flat terrain test (n?=?67), users travelled a longer distance in a shorter time, improving their average speed to 1.28?m/s with the service dog compared to 0.75?m/s without (p?n?=?60). Mounting a threshold/curb in a wheelchair, 41% improved with the service dog (n?=?39). In a test where walkers and wheelchair users picked up three objects off the ground, 44% improved with the service dog (n?=?164). Conclusion: Service dogs significantly improved wheelchair travel speed and distance on flat and ascending terrain, mounting a threshold/curb and picking up objects off the ground.
  • Implications for Rehabilitation
  • For people with motor impairments:

  • Service dogs are most often used as a technical aid to pick up objects (96%), open doors (36%) and pull the wheelchair during travel (34%).

  • Clients’ performance in significant travel in a wheelchair (on flat terrain, on an upslope, mounting a threshold) improved with the service dog compared to their own performance without the dog.

  • Clients’ grasping performance (picking up three significant objects off the ground) improved with the service dog compared to their own performance without the dog.

  相似文献   
995.
Meiotic segregation of mosaic males with a 45,X cell line has been little examined. In this study, we evaluated the risk of aneuploid gametes using fluorescence in situ hybridization (FISH) and DNA fragmentation in ejaculated spermatozoa of three men with sex chromosome mosaicism including a 45,X cell line. Triple- and dual-color FISH were performed. Sperm DNA fragmentation was detected using the TUNEL assay. A significantly increased frequency of XY disomic spermatozoa was observed for patients (P)1 and P2. A significant increase in diploidy and autosomal aneuploidy was found in P2 and P3, respectively. The rate of DNA fragmentation was not different from that observed in a control group. Data from the literature are scarce (only 3 cases reported), making comparison of the present data difficult, especially as the frequencies of the cell lines comprising the mosaicism differed between patients. Furthermore, the proportion of the different cell lines can differ from one tissue to another in the same patient. Whether the relative levels of the several cell lines present in the mosaicism can influence the rate of aneuploid spermatozoa remains unknown.  相似文献   
996.
Mutations causing familial hypertrophic cardiomyopathy (HCM) have been described in at least 11 genes encoding cardiac sarcomeric proteins. In this study, three previously unknown deletions have been identified in the human cardiac genes coding for beta-myosin heavy chain (MYH7 on chromosome 14) and myosin-binding protein-C (MYBPC3 on chromosome 11). In family MM, a 3-bp deletion in MYH7 was detected to be associated with loss of glutamic acid in position 927 (DeltaE927) of the myosin rod. In two other families (HH and NP, related by a common founder) a 2-bp loss in codon 453 (exon 16) of MYBPC3 was identified as the presumable cause of a translation reading frame shift. Taken together 15 living mutation carriers were investigated. Six deceased family members (with five cases of premature sudden cardiac death (SCD) in families MM and NP) were either obligate or suspected mutation carriers. In addition to these mutations a 25-bp deletion in intron 32 of MYBPC3 was identified in family MM (five carriers) and in a fourth family (MiR, one HCM patient, three deletion carriers). In agreement with the loss of the regular splicing branch point in the altered intron 32, a splicing deficiency was observed in an exon trapping experiment using MYBPC3 exon 33 as a test substrate. Varying disease profiles assessed using standard clinical, ECG and echocardiographic procedures in conjunction with mutation analysis led to the following conclusions: (1) In family MM the DeltaE927 deletion in MYH7 was assumed to be associated with complete penetrance. Two cases of reported SCD might have been related to this mutation. (2) The two families, HH and NP, distantly related by a common founder, and both suffering from a 2-bp deletion in exon 16 of MYBPC3 differed in their average phenotypes. In family NP, four cases of cardiac death were documented, whereas no cardiac-related death was reported from family HH. These results support the notion that mutations in HCM genes may directly determine disease penetrance and severity; however, a contribution of additional, unidentified factors (genes) to the HCM phenotype can-at least in some cases-not be excluded. (3) The deletion in intron 32 of MYBPC3 was seen in two families, but in both its relation to disease was not unequivocal. In addition, this deletion was observed in 16 of 229 unrelated healthy individuals of the population of the South Indian states of Kerala and Tamil Nadu. It was not seen in 270 Caucasians from Russia and western Europe. Hence, it is considered to represent a regional genetic polymorphism restricted to southern India. The association of the deletion with altered splicing in transfected cells suggests that this deletion may create a "modifying gene", which is per se not or only rarely causing HCM, but which may enhance the phenotype of a mutation responsible for disease.  相似文献   
997.
Hepatocarcinogenesis sensitivity (Hcs1, 2) and resistance (Hcr1-3) loci have been identified by linkage analysis on rat chromosomes 7 and 1, and 10, 4, and 8, respectively. Cytogenetic studies documented deletions on chromosomes 3 and 6 of neoplastic rat hepatocytes. Hepatocellular carcinomas (HCCs) were produced in F1 hybrid rats between Long-Evans (LE) and Fisher 344 (F344) rats. Scanning of the above chromosomes for loss of heterozygosity (LOH) showed allelic imbalance (AI) at multiple regions on chromosomes 6, 7, and 10q. Detailed deletion mapping of chromosome 10 localized a putative suppressor Hcr1 gene to within a 3.2-cM interval flanked by D10Rat51 and D10Rat121. Two other distinct regions with frequent AIs were found inside the Hcr1 locus, at marker loci including DNaseI and Mrp genes, and in a segment including 4 consecutive markers (D10Rat64, D10Rat182, D10Rat113, D10Rat216). In 40% of HCCs, AI was seen at the p53 locus. AI on chromosome 7 occurred at the Hcs1 locus, where is located c-myc, which is amplified in HCCs, suggesting allelic gain. Most AIs occurred in poorly/moderately differentiated carcinomas, and a few events were seen in well-differentiated tumors on chromosomes 7 and 10. These data suggest that alteration of a cluster of oncosuppressor genes on 10q is important for HCC progression. The existence of AI on segments of rat chromosomes 6, 7, and 10, syntenic to chromosomal segments of human HCCs where chromosomal gains or deletions occur, suggests a commonality of some molecular events in the pathogenesis of HCCs in rats and humans. Our map provides information toward cloning putative oncosuppressor genes associated with this carcinoma.  相似文献   
998.
Over 20 years, 58 cases of PV in young people (46 meeting the full PVSG criteria, 12 with elevated red cell volume and leucocytosis or thrombocytosis, without splenomegaly) were studied and have been followed for periods of 3-24 years. These cases represent approximately 5% of the cases of PV referred to the Department of Nuclear Medicine of St Louis Hospital during this period. They differ from older patients in the initial clinical severity, the short interval between the first symptoms and the diagnosis, frequent presentation with a life-threatening complication (two cases of hepatic vein thrombosis, six thrombotic or haemorrhagic events, six splenectomies, two abortions) and a very enlarged spleen in half the cases. However, after the initial complications, the overall survival is very long (exceeding 70%, even when including the initial complications, at 15 years). The vascular accidents occur exclusively in the phlebotomized patients, the main risk factor being the poor stability of the haematocrit. Only one acute leukaemia was observed among the 14 cases treated by radioactive phosphorus and/or alkylating chemotherapy. The most frequent late complication was evolution towards myelofibrosis. This spent phase seemed to occur earlier in patients treated by phlebotomy. On the basis of this data, we would advise the following therapeutic strategy: phlebotomies, as soon as the diagnosis is established, and a systematic long-term treatment by hydroxyurea with the hope of reducing the number of vascular complications and of delaying the evolution towards the spent phase and the myelofibrosis.  相似文献   
999.
1000.
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