首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Body weight was already shown to be a major factor for the detectability of myocardial activity with conventional cameras and thus, for the optimization of injected activities and or recording times. This study was aimed to identify the factors affecting this detectability on a new solid-state camera showing a high sensitivity of detection (D.SPECT camera Cyclopharma®).Patients and methodsThe study population involved 101 patients, who underwent myocardial SPECT with Sestamibi on a one-day stress/rest protocol. Each conventional acquisition (DST-XL General Electric Healthcare® USA) was immediately followed by a D-SPECT® one. Myocardial activity was determined on each acquisition in counts per seconds and expressed in fraction of the injected activity for assessing the detectability of myocardial activity.ResultsMyocardial activity was on average 12 ± 3 fold higher when recorded with the D-SPECT® camera than with the DST-XL® one. Body weight and especially body mass index (BMI) were the most significant correlates of the detectability of myocardial activity for both cameras. According to these correlations, an increase in the BMI from 25 to 35 kg/m was associated with a 47% decrease in the detectability of myocardial activity at stress with the DST-XL® and of only 30% with the D-SPECT.ConclusionThe detectability of myocardial activity provided by the D.SPECT camera is dramatically higher than that documented for conventional cameras of the DST-XL® type and is affected by the increase in body weight and in body mass index but at a lower rate than for the Anger camera.  相似文献   

2.
3.
IntroductionGated equilibrium radionuclide venticulography is often used to determine left ventricule ejection fraction (LVEF), especially in case of follow up when cardio-toxic drugs are administred. During the last decade, the use of cardiac specific (CZT) gamma cameras has spread. They directly acquire 3D data. We wanted to determine the agreement between three nuclear medicine LVEF measurement techniques. We also wanted to determine the repeatability of these techniques.MethodsBetween April 16, 2016 and February 4, 2017 we consecutively included 77 patients who were adressed to the nuclear medicine department of CHU Martinique for LVEF measurement. Patients were injected with 99*Technetium labelled albumin. Usual planar scintigraphy was performed to serve as reference and 3D data was acquired with a CZT cardiac gamma camera. 3D data was analyzed directly with BPGS software, and also reprojected to planar data which was analyzed like the conventional planar acquisition.ResultsSeventy patients had acquisitions with both gamma cameras. The LVEF values from the CZT camera data were significantly higher than the reference planar LVEF measurements (+6.2 for 3D analysis, P < 0.01, concordance interval [?8.0; 20.3] and +1.7 for planar reprojection, P = 0.01, concordance interval [?8.9; 12.2]. For all three methods, the intra-method concordance intervals were within [?5; 5].ConclusionOur results indicate the same measurement method must be used in case of LVEF follow up. The variation between theses methods could lead to the false conclusion of impairment of LVEF (which is suspected in case of a 10% LVEF drop). Our secondary outcome show a good repeatability for all three techniques. Further studies should be initiated to determine which method is the most accurate and to determine the reproductibility of the CZT data acquisition process.  相似文献   

4.
《Médecine Nucléaire》2014,38(2):111-121
IntroductionThis retrospective study aimed to assess the performances in the detection of coronary artery disease patients of the stress myocardial perfusion imaging (MPI) performed with a semiconductor camera, a very low dose stress-rest protocol and short recording times.Material and methodsWe analyzed consecutive MPI exams, which has been routinely planed with the “D-SPECT” semiconductor camera, a 1-day stress-rest protocol, very low doses of Sestamibi-99mTc (120 MBq at stress and 360 MBq at rest for a 75 kg body weight patient) and short acquisition-times targeting the recording of 500 myocardial kcounts (on average, 8 min for stress and 3 min for rest). The ability to detect coronary artery stenosis (> 50% diameter reduction) was assessed in a group of 118 patients, who had coronary angiography at ≤ 3 months from MPI, and normalcy rate was assessed in a group of 74 patients showing a low pretest probability of coronary artery disease (< 10%).ResultsSensitivity, positive predictive value and global accuracy for identifying the 81 patients with ≥ 1 coronary artery stenosis were 85%, 83% and 78%, respectively; and normalcy rate was 96%. Mean effective doses were: (1) 4.9 ± 1.4 mSv in the group with coronary angiography and where most exams (90%) comprised both stress and rest MPI; and (2) 1.9 ± 1.5 mSv in the low probability group and where most exams (70%) comprised only stress MPI.ConclusionWhen performed with a sensitive semiconductor camera and a very low dose stress-rest protocol, MPI provides high diagnostic performances, equivalent to those documented with conventional cameras in the same study setting, but with dramatic reduction of patients’ radiation.  相似文献   

5.
Resume Les expériences ont porté sur des lapins repartis en deux groupes parallèles — un groupe étant traité avec des aéroions négatifs en concentrations moderées (n = 10 – 40.000; n+ = 1.000) et l'autre sans aéroionothérapie (témoins). Par rapport aux animaux témoins (pas exposés aux aéroions),on a enregistré,sous l'influence de l'aéroionothérapie, que: (1)il y a une tendence de normalisation de la motilité spontanée, deprimée par une alimentation contenant un excès de cholestérol(0,3 g/kg/jour); (2) la lipémie et la cholestérolémie sont restées à un niveau plus bas chez les animaux alimentés au cholestérol; (3) la lipémie et la cholestérolémie, de même que l'iode thyroïdien, sont restées aux valeurs voisines de celles normales,chez les animaux nourris avec un excès (20 mg/kg/jour), de substances antithyroïdiennes naturelles (provenant du chou).
Groups of rabbits were exposed to negative air ions of moderate concentrations (n = 10 – 40,000; n+ = 1,000) while others served as controls. (1) When rabbits were fed a cholesterol-rich diet (0.3 g/kg/day)causing reduction of motility in the control animals, their motility was normalized under air ion treatment. (2) The blood cholesterol and lipid levels of rabbits on a cholesterol-rich diet were lower with air ion treatment than in controls.(3) When rabbits were fed a diet with thyroid blocking agents from cabbage the blood cholesterol and lipid levels and the thyroid iodine content remained unchanged with air ion treatment.

Zusammenfassung Gruppen Kaninchen wurden mit negativen Luftionen in mässigen Konzentrationen (n = 100 000 – 40 000; n+ = 1 000) behandelt, während andere als Kontrollen dienten. (1) Die durch Fütterung von cholesterinreicher Diät (0,3 g/kg/Tag) verminderte Motilität der Tiere wurde unter der Luftionenbehandlung normalisiert. (2) Der durch Fütterung von cholesterinreicher Diät erhöhte Blutcholesterin- und-fettspiegel fiel durch Luftionenbehandlung ab. (3) Der durch Fütterung von strumipriven Substanzen aus Kohl erhöhte Cholesterin- und Fettspiegel im Blut und verminderte Jodgehalt der Schilddrüse wurde durch Luftionenbehandlung nicht beeinflusst.
  相似文献   

6.
Résumé Les auteurs ont isolé plus de 700 souches de bactéries lactiques à partir de raisins, de moûts, de vins de diverses origines et à différents stades de conservation. Ils étudient ici 253 souches de bacilles hétérofermentaires, dans le but d'établir une classification simple et un catalogue permettant un repérage facile des souches.Il est commode de classer les souches d'après la fermentation des pentoses, en raison de la netteté de ces tests, alors que parfois ceux appliqués à d'autres sucres ont des caractères moins tranchés. On retrouve alors la classification qui avait été déjà donnée par Vaughn, Douglas et Fornachon en 1949.Les bacilles pentoses négatifs (26 souches) forment l'espèce Lactobacillus fructivorans. Ceux qui font fermenter seulement l'arabinose (4 souches) ou seulement le xylose (155 souches) correspondent respectivement à Lactobacillus desidiosus et à Lactobacillus hilgardii. L'espèce Lactobacillus brevis comprend les bacilles pentoses positifs (68 souches).
A study of two hundred and fifty strains of lactic acid bacteria
Summary The authors have isolated more than 700 strains of lactic acid bacteria found in grapes, musts and wines of various origins and at different states of conservation. They study in this work 253 strains of heterofermentative bacilli in order to work out a classification and a catalogue allowing easy identification of the strains.It is convenient to classify the strains from the fermentation of pentoses, on account of the accuracy of these tests, tests on other sugars having sometimes less specific characters. The results are consistant with the classification already established by Vaughn, Douglas and Fornachon in 1949.Pentose negative bacilli (26 strains) constitute the species Lactobacillus fructivorans. The ones which ferment only arabinose (4 strains) or only xylose (155 strains) correspond to Lactobacillus desidiosus and Lactobacillus hilgardii. The pentose positive strains (68) belong to the species Lactobacillus brevis.
  相似文献   

7.
《Médecine Nucléaire》2017,41(2):83-92
IntroductionRadionuclide ventriculography provides a reproducible measurement of the left ventricular fraction ejection (LVEF) but with a significant body radiation (effective dose of 5,9 mSv for the injection of 850 Mbq of 99mTc). The highly sensitive semi-conductor (CZT) cameras could allow decreasing the injected activity by a factor 3, similarly to that of myocardial perfusion imaging. Our study was aimed to determine whether the LVEF measurement provided by radionuclide ventriculography on the CZT D-SPECT camera is impacted by a 70% reduction in recorded counts.Materials and methodsAfter the in vivo labeling of red blood cells with 850 MBq of 99mTc, 49 patients completed a conventional 2D recording (Conv-2D) on Anger camera followed by a 3D recording on the D-SPECT camera (3D-100%). The CZT recordings of all projections were subsequently shortened to 30% of their initial durations (3D-30%) in order to assess the LVEF measured with a 70% reduction in recorded counts.ResultsMean LVEF values were 62.7 ± 11.1% on Conv-2D and higher on both 3D-100% (66.8 ± 14.8%, P < 0.001) and 3D-30% (66.3 ± 15.7%, P < 0.001). The correlation coefficients with the LVEF determined with the reference Conv-2D method were equivalents for 3D-100% (r2 = 0.73) and 3D-30% (r2 = 0.70) and with a similar level of overestimation for the highest LEVF values.ConclusionA 70% reduction in recorded counts does not significantly impact the LVEF measured with radionuclide ventriculography on the CZT D-SPECT camera. These values are coherent with those obtained with the reference 2D method but with a clear overestimation for the highest LVEF values.  相似文献   

8.
《Geobios》1986,19(5):549-571
The paleoflora described and pictured in this paper has been collected in two deposits of the area of Demnate: the OT6 bis drilling in the oriental Haouz and an exposure in the Rhojdamas (High-Atlas). Two completely different associations have been characterized: one hygrophilous and autochtonous of the «Stephanian type and the other mesoxerophilous and allochtonous (vegetation of the upland?) of the «Autunian type. In the OT6 bis drilling, the two floras alternate so that it is impossible to draw a precise boundary between the Stephanian and Autunian. In the Rhojdamas, only the Autunian flora has been identified. Such a combination of the two floras has similarly been recorded in several stephanian basins of the French Massif Central.  相似文献   

9.
Absence of the vas deferens is a rare cause of male infertility, associated with mutations in the cystic fibrosis transmembrane regulator (CFTR) gene in about 80% of cases. Only limited published data are available concerning the correlation between genotype and reproductive tract abnormalities observed in this disease: presence or absence of seminal vesicles and parts of the epididymis, symmetrical or asymmetrical lesions, testicular volumes. We screened 47 patients for the 13 most common CFTR mutations on the cystic fibrosis gene and for the 5-thymidine variant of the polythymidine tract of intron 8. Renal, scrotal and transrectal ultrasonography was performed in each patient to explore the testes and reproductive tract. All patients presented absence of the ampullae of the vas deferens. Forty patients presented bilateral absence of the vas deferens and 7 presented unilateral absence of the vas deferens. At least one mutation of the cystic fibrosis gene was present in 64% of cases: 47% had the ΔF 508 mutation and 63% had the 5T allele. No mutation was detected in seventeen patients, including 3 patients with unilateral renal agenesis and 3 patients with unilateral absence of the vas deferens. No differences were observed for seminal vesicles and symmetry of vesicular and epididymal abnormalities between patients with or without CFTR gene mutations, but epididymal abnormalities were significantly more frequent in the group without mutation (p=0.01). Testicular volumes were significantly lower in the patients without mutation or with the 5T allele only, than in the patients with at least one CFTR gene mutation: 10.7±4.1 ml versus 15.1±4.5 ml, respectively (p<0.001). In conclusion, in cases of isolated absence of the vas deferens, there is no difference in sperm duct abnormalities between patients with or without CFTR gene mutation. These results suggest that other genetic or environmental determinants are required to explain a common pathogenesis for these malformations. The decreased testicular volume of patients without CFTR gene mutation or with the 5T allele only suggests the existence of an unidentified secretory or mixed factor involved in these forms of absence of the vas deferens.  相似文献   

10.
11.
A Laberge  P M Bernard  L Bernard 《CMAJ》1988,138(9):824-826
To estimate the incidence of fracture of the proximal end of the femur in people aged 50 years or older living in the Quebec area in 1971, 1976 and 1981 we determined the number of admissions for such fractures to the 15 acute care hospitals in the region. From 1971 to 1981 the number of fractures increased by 71%; the increases for those aged 75 to 84 years and 85 years or over were 98% and 118% respectively. The variation is only partly explained by changes in sex and age distribution of the population; the incidence rates also increased. Among men aged 75 to 84 years the incidence rate per 1000 person-years rose from 2.63 in 1971 to 5.22 in 1981, an increase of 98%; the corresponding figures for men aged 85 years or more were 9.76 and 16.91, an increase of 73%. Among women aged 75 to 84 years the rate rose from 7.28 to 8.81, an increase of 21%; the corresponding figures for women aged 85 years or more were 20.40 and 24.27, an increase of 21% and 19% respectively.  相似文献   

12.
A. Mirimanoff 《Protoplasma》1953,42(2):250-260
Résumé Le présent travail expose quelles sont les réactions de la cellule végétale lorsque cette dernière est soumise à l'association d'un toxique et d'un « mouillant » (Netzmittel).Les variables sont: la nature de la cellule végétale, celle du toxique et celle du mouillant.Alors que les mouillants cationiques, eux-mêmes toxiques, exercent une simple action additive, les mouillants anioniques révèlent dans de nombreux cas une synergie de toxicité. Celle-ci se manifeste surtout avec les champignons et les bactéries Gram+, les végétaux supérieurs se montrant indifférents. Cette synergie varie également avec la structure moléculaire du mouillant.Les mouillants non ioniques peuvent au contraire exercer une action antagoniste, c'est-à-dire diminuer la toxicité.Ce dernier phénomène se produit dans certains cas à la suite d'une réaction chimique entre le mouillant et le toxique; la nature de la cellule est alors indifférente. Dans d'autres cas, il y a absence de réaction chimique et le phénomène ne se produit qu'avec certains types de cellules (champignons surtout).La nature chimique du toxique joue, dans la synergie, un rôle moins important que dans l'antagonisme.Des hypothèses sont formulées pour tenter d'élucider le mécanisme des cas de synergie et d'antagonisme.  相似文献   

13.
Nawal El Ansari 《Andrologie》2008,18(2):127-130
Kallmann syndrome (KS) is a rare, heterogeneous disorder consisting of congenital hypogonadotropic hypogonadism, associated with anosmia (or hyposmia) and other clinical manifestations such as mirror movements, and renal, urological and neurosensory disorders. The presence of anosmia with micropenis in boys is suggestive of the diagnostic of KS. In KS, the GnRH neurons do not migrate correctly from the olfactory placode to the hypothalamus during development and olfactory bulbs also fail to form, leading to anosmia. Mutations in KAL1 which encodes Anosmin-1, are responsible for the X-linked form of KS. Anosmin-1 is normally expressed in the brain, facial mesenchyme, mesonephros and metanephros. It is required to promote migration of GnRH neurons into the hypothalamus. It also allows migration of olfactory neurons from the olfactory bulbs to the hypothalamus. The loss of function mutations in FGFR1 “fibroblast growth factor” were identified in 2003 as a cause of autosomal forms of this disease. An additional autosomal cause of Kallmann syndrome was recently identified by a mutation in the prokineticin receptor-2 gene (PROKR2) (KAL-3) and its ligand prokineticin 2 (PROK2) (KAL-4). Mutations in these genes induce various degrees of olfactory and reproductive dysfunction, but not the other symptoms seen in KAL-1 and KAL-2 forms of KS. Neuropilin2, which has an important role in migration of GnRH neurons, is a recent candidate gene for KS. The authors describe the genetic features and recent findings of KS, necessary to understand this disease.  相似文献   

14.
Résumé Avant d'entrer en contact, les surfaces de fusion des processus palatins subissent des modifications. Certaines cellules épithéliales superficielles deviennent turgescentes, alors que d'autres conservent un aspect dense et aplati, elles se lysent et éclatent. Des noyaux semblables à ceux des assises profondes se retrouvent en surface, paraissant migrer vers le bourgeon antagoniste. Des projections filamenteuses apparaissent, quelques unes établissant un contact avec l'épithélium opposé, d'autres restant seulement sous forme d'expansion. Ces observations sont concordantes en microscopie photonique et en microscopie électronique à balayage.
Modification of the medial epithelium of the palatal shelves of mice at the prefusion stage. A light and scanning electron microscopy study
Summary The fusion surfaces of the palatal processes are modified before coming into contact. Several superficial epithelial cells become hypertrophied, undergo lysis and burst, whereas others remain flattened and densely stained. Nuclei, similar to those localized in deeper layers are found on the surface and seem to migrate towards the opposite process. Filamentous projections appear and some establish a linkage with the opposite epithelium, whereas others expand freely from the surface. Light microscope observations agree with scanning electron microscopy findings.
  相似文献   

15.
16.
17.
18.
《Geobios》1987,20(6):789-810
The micropaleontological and sedimentological analysis of the cuttings and core-samples extracted from a certain number of borings conducted seaside Casamance, western Casamance and eastern Casamance (fig. 1), enabled the researches to determine Casamance stratigraphy and paleoecology during the tertiary period. The microfauna gathered (foraminifera and ostracoda) makes it possible to characterize the biozones P1 to P15/P16 followed by the biozones N1/N2 to N14, bringing into evidence the existence of Paleogene and Neogene which are separated by a gap of changeable amplitude.The sedimentological study has revealed the presence of a certein number of landmarks and lithologic mineralogical sets which seem to be constant in the studied boring.  相似文献   

19.
Digestion by restriction enzymes has been carried out on polymerase chain reaction products of the mitochondrial DNA control region of round sardine (Sardinella aurita) samples coming from the Eastern Atlantic and the Mediterranean Sea. The results show i) that, though the habitat is continuous, there is no gene flow between the two basins where two genetically differentiated groups can be recognized, ii) that each basin is genetically homogeneous and, iii) that the haplotypic diversity in the Mediterranean is between two and three times smaller than that observed in the Atlantic. These results can hardly be explained by a recent colonization from the Eastern Atlantic. This suggests that, for S. aurita and some other species, the Mediterranean Sea is genetically little influenced by the Eastern Atlantic.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号