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11.
12.
M H Kormann-Bortolotto M de A Smith J Toniolo Neto 《Mechanisms of ageing and development》1992,65(1):9-15
The fragile site expression under conditions of folate deprivation was compared in the chromosomes from 5 Alzheimer's disease (AD) female patients, 5 healthy elderly females and 5 healthy young females. Although different fragile sites were observed in the three groups, nevertheless, more similarities were found between the AD patients and elderly normal donors. The only fragile site common to all groups was 3p14. This site was the most frequent in the young donors group. In both AD and elderly control groups we observed a higher frequency of fragility in 6p21, but not in the young controls. Other interesting fragility points observed in these two groups were: 6q21 and 14q24 (in the AD patients) and 9q13, 14q24 and 17q21 (in the healthy aged). 6p21 and 17q21 have been proposed as 'new' fragile sites. We confirm the existence of these fragile sites and comment that in these bands the genes MTBT2 and MTBT1, which are microtubule (beta) associated protein tau-like and tau 1, respectively, are mapped. The tau protein is a component of paired helical filaments which accumulate in degenerating neurons in the brain of patients with AD and with less intensity of normal elderly individuals. 相似文献
13.
Ulisses Xavier da Silva Neto Ivaldo Gomes de Moraes Vania Portela Ditzel Westphalen Renato Menezes Everdan Carneiro Luiz Fernando Fariniuk 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(2):e53-e57
OBJECTIVE: The aim of this study was to measure leakage of 4 resin-based sealers. STUDY DESIGN: Four groups of premolars (n = 60) were prepared using GT Rotary files and the crown-down technique and filled by the single-cone technique with AH26, AHPlus, EndoREZ, and an experimental MBP as sealer. Leakage was measured using the fluid filtration method after 15, 30, and 60 days and determined as microL/min(-1) x 10 psi. RESULTS: Statistical analysis by ANOVA and Tukey HSD test indicated that root fillings with AH Plus and the MBP showed lower leakage values after 15 days (P < .05). At 30 days, AH26 presented higher leakage values when compared to other sealers (P < .05). At 60 days, MBP and AH Plus presented the lower leakage values, differing significantly from EndoREZ (P < .05). CONCLUSION: It was observed that AH Plus and the experimental MBP showed lower leakage after 60 days than AH 26 and EndoREZ. 相似文献
14.
AG Nettetal 《MedR Medizinrecht》2007,25(11):664-666
Abstrakt 1. Nimmt ein Patient einen ihm von seinem (Zahn-)Arzt einger?umten Exklusiv-Termin nicht wahr, obwohl er auf dessen Eigenschaft
ausdrücklich hingewiesen wurde, so hat er dem (Zahn-)Arzt den Behandlungsausfall abzüglich eines angemessenen Eigenanteils
des (Zahn-)Arztes zu ersetzen.
2. Die Ersatzpflicht tritt auch dann ein, wenn der Patient den Termin nicht in der in dem Behandlungsvertrag vorgesehenen
Frist absagt. Eine hierfür seitens des (Zahn-)Arztes bestimmte Frist von zwei Tagen vor Behandlungsbeginn stellt sich für
den Patienten grunds?tzlich auch nicht als unangemessene Benachteiligung i.S. des § 307 BGB dar.
3. Ein Anspruch des Arztes entf?llt auch bei nur mündlicher Vereinbarung nicht unter dem Gesichtspunkt des § 4 Abs. 5b BMV-Z,
denn diese Vorschrift ist teleologisch dahin zu reduzieren, dass nur zahn?rztliche Honoraransprüche aus erfolgten Behandlungen
schriftlich vereinbart werden müssen. Soweit es jedoch um einen vertraglichen Anspruch wegen einer Leistungsst?rung geht,
vermag das Schriftformerfordernis des § 4 Abs. 5b BMV-Z grunds?tzlich nicht einzugreifen. (Leits?tze des Bearbeiters) 相似文献
15.
16.
Early during rat thymus ontogeny, an important proportion of thymocytes
expresses IL-2R and contains IL-2 mRNA. To investigate the role of the
IL-2-IL-2R complex in rat T cell maturation, we supplied either recombinant
rat IL-2 or blocking anti-CD25 mAb to rat fetal thymus organ cultures
(FTOC) under several experimental conditions. The IL-2 treatment initially
stimulated the growth of thymocytes and, as a result, induced T cell
differentiation, but the continuous addition of IL-2 to rat FTOC, as well
as the anti-CD25 administration, resulted in cell number decrease and
inhibition of thymocyte maturation. These results indicate that immature
rat thymocytes bear functional high- affinity IL-2R and that IL-2 promotes
T cell differentiation as a consequence of its capacity to stimulate cell
proliferation. Modifications in TCR alpha beta repertoire and increased
numbers of NKR- P1+ cells, largely NK cells, were also observed in
IL-2-treated FTOC. Furthermore, IL-2-responsiveness of different thymocyte
subsets changed throughout thymic ontogeny. Immature CD4-CD8-cells
responded to IL-2 in two stages, early in thymus development and around
birth, in correlation with the maturation of two distinct waves of thymic
cell progenitors. Mature CD8+ thymocytes maximally responded to IL-2 around
birth, supporting a role for IL-2 in the increased proliferation of mature
thymocytes observed in vivo in the perinatal period. Taken together, these
findings support a role for IL-2 in rat T cell development.
相似文献
17.
Ghosh D; Stewart DR; Nayak NR; Lasley BL; Overstreet JW; Hendrickx AG; Sengupta J 《Human reproduction (Oxford, England)》1997,12(5):914-920
The present study was undertaken to assess the temporal association between
the profiles of serum concentrations of oestradiol-17beta, progesterone,
chorionic gonadotrophin (CG) and relaxin in pregnancies established
naturally, and after embryo transfer, as well as in failed pregnancies in
rhesus monkeys. In naturally mated cycles (group 1) a conception rate of
75% was obtained. In group 1, the mean day of CG detection in serum was
11.5 +/- 1.9 day post-ovulation, and for relaxin, 9.0 +/- 2.5 day
post-ovulation. In group 2, embryo transfer to synchronous, non-mated
surrogate recipients was performed; seven embryo transfer cycles yielded
three pregnancies which were allowed to continue to term and normal infants
were delivered. In embryo transfer cycles the mean day of CG detection was
14.8 +/- 1.8 day post- ovulation, and for relaxin, 11.4 +/- 2.6 day
post-ovulation. A delay of about 3 days was observed in the appearance in
circulation of CG (P < 0.05) and also of relaxin (P < 0.05) between
natural mated and embryo transfer conception cycles. Significant
differences (P < 0.05 for progesterone and P < 0.03 for oestradiol)
were obtained for the areas under the curves for progesterone and
oestradiol between days 12 and 16 in conception cycles compared with failed
pregnancies. These data provide the first observation of the normal
hormonal signals associated with maternal recognition of transferred
embryos during the peri- implantation period, and suggest that the use of
such an experimental primate embryo transfer model may help to elucidate
components of maternal and embryonic signal-response mechanisms during
embryo implantation.
相似文献
18.
A rapid microagglutination test for the diagnosis of Legionella pneumophila (serogroup 1) infection 总被引:4,自引:3,他引:4 下载免费PDF全文
A rapid microagglutination test has been developed which can be performed in 30 minutes. Ninety-seven percent of 96 patients diagnosed as having Legionella pneumophila (serogroup 1) infection by indirect immunofluorescence were also detected by the rapid microagglutination test. 相似文献
19.
Performance characteristics of a rapid new immunochromatographic test for detection of antibodies to human immunodeficiency virus 总被引:1,自引:0,他引:1
Ribeiro-Rodrigues R Ferreira da Silva Pinto Neto L Cunha CB Cabral VP Dietze R 《Clinical and diagnostic laboratory immunology》2003,10(2):303-307
A new immunochromatographic rapid test (Rapid Check HIV 1 and 2; Núcleo de Doen?as Infecciosas) for the detection of antibodies to human immunodeficiency virus type 1 and type 2 in human samples (whole blood, serum, and plasma) was evaluated and compared to the commercially available Determine (Abbott Laboratories). When whole-blood samples were evaluated, the specificity and sensitivity of both tests were 100%. However, when plasma samples were used, sensitivity for the Rapid Check HIV 1&2 and the Determine tests were 100 and 98.58%, respectively. The observed specificity for plasma samples was 98.94% for the Rapid Check HIV 1&2 and 96.97% for the Determine test. The results presented here are encouraging and support the adoption of both tests as an alternative to enzyme-lined immunosorbent assay and/or Western blots in regions where laboratorial infrastructure is not available or for use in the management of occupational accidents for healthcare workers. 相似文献
20.
Luiza Guilherme Ed cio Cunha Neto Guilherme Renesto Anna C. Goldberg Josely Chiarella Rachel Snitcowsky Ma. Helena Kiss Cl vis Silva Jorge Kalil 《Human immunology》1996,47(1-2):20
β-hemolytic streptococcal infection in developing countries still causes thousands of cases of Rheumatic Fever (RF). Molecular mimicry between streptococcal M protein (strep M) and heart components has been proposed as the triggering factor leading to autoimmunity in individuals with genetic susceptibility, which is linked to different HLA-DR alleles in different populations. In our hands, RF was significantly associated to HLA-DR7/53. Previous work in our lab has shown that heart-infiltrating T cells that simultaneously recognize strep M and heart proteins. Further, such T cells predominantly recognized the 81-103 strep M5 epitope. In this work, we analysed the proliferative response of peripheral blood mononuclear cells of 99 RF patients and 40 normal controls. Eighty-nine of the RF patients were HLA-typed. As among heart-infiltrating T cells, the 81-103 strep M5 protein epitope is the most frequently recognized epitope among RF PBMC (35.4%), against a 7.5% frequency of proliferation among normal controls (p=0.0018, chi square). However, the 81-103 epitope was as frequently recognized by HLA-DR7,53 positive as by negative individuals (45.2% vs 54.8%, respectively). Taken together, the results suggest that the 81-103 strep M5 epitope may be the immunodominant epitope, “promiscuously” recognized by T cells in a genetically diverse population. The demonstration that molecular mimicry is targeted to a discrete immunodominant “promiscuous” epitope in strep M5 may allow the development of a safe anti-streptococcal synthetic vaccine devoid of such epitopes. 相似文献