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21.
In many patients with myelodysplastic syndromes or acute myeloid leukemia, complex chromosome aberrations can be seen, among which aberrations of chromosome 5 constitute a substantial part. With conventional cytogenetic technique, these aberrations are often identified as deletions or monosomy 5. We analyzed nine patients who, under conventional cytogenetic analysis, showed deletion or monosomy 5. We used fluorescence in situ hybridization with whole-chromosome painting probes to identify the counterpart chromosome and locus-specific identifiers for 5q31 and 5q33 approximately q34. A deletion of 5q was found concomitant with unbalanced translocations. Our results and cases from the literature showed that material from chromosome 5 could be translocated to almost all chromosomes. All patients but one had short survival; this one patient had a preserved 5q31 and 5q33 approximately q34 but a deletion of the q-arm more centromeric than these bands. In eight of the nine patients, further 14 translocations were revealed, not involving chromosome 5.  相似文献   
22.
The aim of this study was to investigate the relationship between mucosal gizzard lesions and caecal Clostridium perfringens counts. Gross pathological changes in the gizzard and small intestine, and caecal C. perfringens counts from 1217 meat-type chickens were recorded during the course of six experiments and were statistically analysed. C. perfringens counts increased significantly (P < 0.001) with the severity of mucosal gizzard lesions. Mucosal gizzard lesions were more prevalent than necrotic enteritis. Correcting for the pen and necrotic enteritis within experiment, mucosal gizzard lesions explained 31.8% of the variation in C. perfringens counts. Mucosal gizzard lesions and age together explained 59.1% of the variation in C. perfringens counts. The mean ages of birds with moderate and severe mucosal gizzard lesions were 1.7 and 0.8 days lower than the mean age of birds with necrotic enteritis, respectively. The association between mucosal gizzard lesions and high C. perfringens counts might be of importance when attempting to improve production efficiency, health and the welfare of the chickens.  相似文献   
23.
Periodontal status was studied at the mesiobuccal, midbuccal and distobuccal aspects of contralateral pairs of canines in 22 postorthodontic patients aged 30 to 51 years with a mean time of 26.4 years (SD, 5.6) out of active treatment. The pretreatment models showed one canine erupting severely to the labial ("ectopic") with a contralateral canine in good arch alignment (control). None of the patients experienced relapse of the "ectopic" canine in a labial direction, and none had missing teeth, malalignment, overhanging restorations or open tooth contacts adjacent to the canines evaluated. Periodontal parameters were examined using a Michigan #0 probe with Williams markings. A nonstandardized light force was used and the measurements were rounded to the nearest millimeter. The results demonstrated statistically significant differences between the canines in probing attachment and bone levels (mean, 0.75; SD, 0.92; P less than 0.01) and width of attached gingiva (mean, 0.50; SD, 1.07; p less than 0.05) at the midbuccal aspects. The reason for these differences could only be speculated upon.  相似文献   
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Intraabdominal postoperative or posttraumatic infections remain a major threat to life in spite of generation after generation of increasingly effective antimicrobial drugs indicating the importance of immunological host defense failure following major trauma or surgical complications. The spectrum of infectious postoperative or posttraumatic complications can, in part, be explained by pathogenic factors inherent to the methodology of modern surgical intensive care and techniques. This report presents a survey of the historical background as well as current concepts of the multiple systems organ failure syndrome as related to postoperative or posttraumatic intraabdominal infectious complications. The pathophysiology of nosocomial infectious complications in the intensive care unit setting is analyzed. The concept of gut origin sepsis is presented and possible preventive and therapeutic actions discussed. A judicious use of antimicrobial drugs on strict indications is emphasized as is the importance of increased knowledge of the interactions between the gut flora, antibiotics, and absence of enteral nutrition.
Resumen Las infecciones intraabdominales postoperatorias o postraumáticas siguen representando una amenaza grave para la vida a pesar de generación tras generación de drogas antimicrobianas de creciente efectividad, lo cual señala la importancia de la falla de los mecanismos inmunes de defensa del huésped que se presenta después de trauma mayor o acompanando las complicaciones quirúrgicas. El espectro de las complicaciones infecciosas postoperatorias o postraumáticas puede ser explicado en parte por factores patogénicos inhérentes a la tecnología y metodología del moderno cuidado intensivo del paciente en estado crítico. El presente informe reporta una revisión de los antecedentes históricos y de los conceptos actuales sobre el sindrome de falla orgánica multisistémica relacionado con complicaciones infecciosas intraabdominales postoperatorias o postraumáticas. Se analiza la patofisiología de las complicaciones infecciosas nosocomiales en el marco de la unidad de cuidado intensivo. Se hace énfasis sobre el uso juicioso de drogas antimicrobianas según indicaciones estrictas, asi como sobre la importancia de un mayor conocimiento sobre las interacciones entre la flora intestinal, los antibióticos, y la ausencia de nutrición enterai.

Résumé Les infections intra-abdominales postopératoires ou post-traumatiques continuent de menacer le pronostic vital malgré une amélioration constante des antibiotiques ce qui met l'accent sur l'échec des moyens de défense immunologiques après les traumatismes majeurs ou les complications chirurgicales. Le spectre des complications infectieuses postopératoires ou post-traumatiques peut, en partie, être expliqué par des facteurs pathogéniques inhérents à la méthode des soins intensifs et techniques modernes. Ce travail présente l'historique et les concepts actuels de défaillance polyviscérale en rapport avec des complications infectieuses intra-abdominales postopératoires ou post-traumatiques. La pathophysiologie des complications infectieuses nosocomiales dans l'unité des soins intensifs est analysée. La conception de sepsis d'origine intestinale est présentée et les actions préventive et thérapeutique sont discutées. L'utilisation judicieuse des antibiotiques est soulignée, ainsi que les interactions entre la flore intestinale, les antibiotiques et l'absence de nutrition entérale.
  相似文献   
26.
On the basis of ethnological research methods, the everyday life of one Danish and one American kindergarten class in school is described. In the American kindergarten class teaching of the three Rs (reading, writing and arithmetic) is predominant, whereas play constitutes the life in the Danish classroom. The study shows that the American teacher-controlled academic practice and the children's concrete cultural background contribute to the development of motivation for learning at the age of 6 years. On the other hand, the American children are very egocentric and have difficulties in participating in group activities. In contrast, the more child-controlled practice in the Danish kindergarten develops social competence but neglects the development of motivation for learning. With comprehensive development as the educational aim, neither the American teacher-controlled academic practice nor the Danish child-controlled play approach is quite adequate, which calls for a new paradigm in early childhood education.  相似文献   
27.
In the present study we measured brain activation, with functional magnetic resonance imaging (fMRI) during the execution of a covert semantic categorization task. This involves activation of working memory and internal concept generation. Previous brain imaging studies of covert verbal fluency have shown widespread activation in the frontal and temporal lobes, and anterior cingulate. However, most of these studies have employed simple stimulus tasks with repetition of words e.g., beginning with a certain letter of the alphabet. Moreover, the subject is typically cued (either visually or auditory) every 2-5 second. In the present study we used a "single-cue" instruction at the beginning of each activation period where the subject was instructed to internally generate category specific names related to: "States in the USA," "UK Soccer clubs," and "Male names" during 54s periods. The three activation periods were compared to three baseline periods in which the subject was instructed to imagine mentally "lying on a beach and looking at the sky." Functional MRI was performed with a 1.5T Siemens Vision scanner. Initial TIW 3D FLASH scanning of anatomy was done, and thereafter, serial imaging with 60 BOLD sensitive echo planar whole brain measurements were done during the active and passive tasks. Main activation areas were found in the left middle frontal gyrus, partially overlapping with Brodmann area 9. This is in agreement with previous studies of increased activation in the left frontal lobe, and may indicate a left frontal neural network for accessing the mental lexicon.  相似文献   
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A study was carried out to investigate urinary protein excretion patterns by means of SDS-polyacrylamide-gel-electrophoresis (SDS-PAGE) in renal cell cancer patients who had previously been exposed to high levels of trichloroethylene. Thirty-eight out of 41 (93%) renal cell cancer patients investigated had former extensive trichloroethylene exposure, but only 23 out of 50 (46%) renal cell cancer patients without a history of occupational exposure to trichloroethylene revealed urinary protein patterns indicative of toxic effects on the tubular system. One hundred controls without histories of overt renal disease and not occupationally exposed to trichloroethylene were examined in the same way; only 11 (11%) of them displayed protein excretion patterns indicative of damage to the renal tubule. These results are supported by alpha 1-microglobulin excretion data. The following conclusions are drawn: (1) Substantially more cases of tubular damage are found amongst renal cell carcinoma patients having been exposed to substantial levels of trichloroethylene over many years as compared with renal cell carcinoma patients not exposed to trichloroethylene. (2) The results support the view that chronic tubular damage is a precondition for the nephrocarcinogenic effect of trichloroethylene. (3) The findings indicate that urine protein patterns, on the basis of the SDS-PAGE methodology, represent a 'biological effect parameter' for the medical surveillance of persons occupationally exposed to trichloroethylene.  相似文献   
30.
Auxin as a positional signal in pattern formation in plants   总被引:28,自引:0,他引:28       下载免费PDF全文
By using a novel, extremely sensitive and specific gas chromatography-mass spectrometry technique we demonstrate in Pinus sylvestris (L.) trees the existence of a steep radial concentration gradient of the endogenous auxin, indole-3-acetic acid, over the lateral meristem responsible for the bulk of plant secondary growth, the vascular cambium. This is the first evidence that plant morphogens, such as indole-3-acetic acid, occur in concentration gradients over developing tissues. This finding gives evidence for a regulatory system in plants based on positional signaling, similar to animal systems.  相似文献   
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