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1.
2.
Nestin expression persists in astrocytes of organotypic slice cultures from rat cortex 总被引:11,自引:0,他引:11
Rainald Schmidt-Kastner Christian Humpel 《International journal of developmental neuroscience》2002,20(1):29-38
Nestin is an intermediate filament protein typical for neural precursor cells that is down-regulated in the post-natal rodent brain. Re-expression of nestin has been observed in reactive astrocytes after injury. In this study, organotypic slice cultures from rat cortex were examined for expression of nestin and glial fibrillary acidic protein between 2 and 8 weeks in culture. Immunoreactivity for nestin and glial fibrillary acidic protein was seen in astrocytes which persisted throughout the observation period. Immunofluorescence double labeling showed widespread co-localization of nestin and glial fibrillary acidic protein. Image analysis revealed that levels of nestin-immunoreactivity plateaued after 5 weeks in culture. By comparison nestin immunoreactivity was absent from glial cells of the cortex in mature rats. These immunohistochemical findings of a persistent expression of nestin in glial cells of organotypic slice culture of the rat cortex indicate a different time course of glial maturation in vitro. This difference could be related to the altered trophic stimulation in vitro; differences in neuronal maturation, activity or survival; slow degeneration of the vasculature; or intrinsic properties of astrocytes. 相似文献
3.
G C Conoscenti S Alberico P Bogatti A Maieron L Fischer Tamaro C Gigli 《Minerva ginecologica》1991,43(12):549-553
The Authors examine the correlation between hypertensive disorders of pregnancy and fetal growth. The results of a study of 342 pregnancies, confirm a significant correlation between hypertension and fetal growth retardation. These findings, so evident in moderate and severe hypertension, have also been confirmed in cases of mild hypertension. The medical treatment also in the pregnancies with mild hypertension, and a larger utilisation of operative deliveries, determined a decrease in perinatal mortality and morbidity. 相似文献
4.
C K Fischer 《The Journal of reproductive medicine》1991,36(1):74-76
Fifteen cases of microtuboplasty were done as outpatient procedures at low cost and with increased patient convenience. Advances in outpatient surgery at free-standing surgery centers have allowed many new patient care innovations, and microsurgery should now be considered an outpatient procedure for gynecologic patients. Outpatient microtuboplastic surgery is not only feasible but perhaps preferable to that done as an inpatient procedure. 相似文献
5.
C. Fischer W. Gross J. Krüger M. Cremer F. Vogel T. Grimm 《Annals of human genetics》2006,70(2):237-248
For several genetic diseases two biological phenomena have been recognised as important: germline mosaicism; and different new mutation rates in males and females depending on mutation type. Both principles have been investigated separately and their influence on risk estimation in families has been exemplified in the literature. The aim of this paper is to present a general model that includes mosaicism and different new mutation rates. Mosaicism is introduced by defining additional alleles at the disease locus in combination with adapted segregation rules. Taking Duchenne muscular dystrophy as an example, we derive the conditions which have to be fulfilled for a population in mutation selection equilibrium. Our approach describes the model at the population level and not in individual subjects. This has the advantage of being able to use well known algorithms for the calculation of likelihoods in pedigrees, and to include additional diagnostic information such as marker genotypes and carrier deletion test results. We demonstrate the impact of the new model on a typical pedigree. In families where the patient is not available, the distinction between point mutations and deletions is important, since often molecular diagnostic tests for females can only screen for deletions. Negative deletion test results can now be included in the risk calculations. 相似文献
6.
L.A. Fischer T. Menné C. Avnstorp G.B. Kasting† J.D. Johansen† 《The British journal of dermatology》2009,161(3):560-567
Background Hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC) is a synthetic fragrance ingredient. Case reports of allergy to HICC appeared in the 1980s, and HICC has recently been included in the European baseline series. Human elicitation dose–response studies performed with different allergens have shown a significant relationship between the patch-test threshold and the repeated open application test (ROAT) threshold, which mimics some real-life exposure situations. Fragrance ingredients are special as significant amounts of allergen may evaporate from the skin.
Objectives The study aimed to investigate the relationship between elicitation threshold doses at the patch test and the ROAT, using HICC as the allergen. The expected evaporation rate was calculated.
Materials and methods Seventeen HICC-allergic persons were tested with a dilution series of HICC in a patch test and a ROAT (duration up to 21 days). Seventeen persons with no HICC allergy were included as control group for the ROAT.
Results The response frequency to the ROAT (in μg HICC cm−2 per application) was significantly higher than the response frequency to the patch test at one of the tested doses. Furthermore the response rate to the accumulated ROAT dose was significantly lower at half of the doses compared with the patch test. The evaporation rate of HICC was calculated to be 72% over a 24-h period.
Conclusions The ROAT threshold in dose per area per application is lower than the patch test threshold; furthermore the accumulated ROAT threshold is higher than the patch test threshold, which can probably be explained by the evaporation of HICC from the skin in the open test. 相似文献
Objectives The study aimed to investigate the relationship between elicitation threshold doses at the patch test and the ROAT, using HICC as the allergen. The expected evaporation rate was calculated.
Materials and methods Seventeen HICC-allergic persons were tested with a dilution series of HICC in a patch test and a ROAT (duration up to 21 days). Seventeen persons with no HICC allergy were included as control group for the ROAT.
Results The response frequency to the ROAT (in μg HICC cm
Conclusions The ROAT threshold in dose per area per application is lower than the patch test threshold; furthermore the accumulated ROAT threshold is higher than the patch test threshold, which can probably be explained by the evaporation of HICC from the skin in the open test. 相似文献
7.
Mielke H. Daniel W. Deicher H. Drommer W. Fischer M. Fritsch R. Mller-Vahl H. Sybrecht G. W. 《Clinical rheumatology》1987,6(2):26-34
Clinical Rheumatology - Rheumatoid arthritis (RA) as a systemic disease can attack many other organs in addition to the joints. A variety of pathological lesions of the blood vessels are... 相似文献
8.
Wolfgang B. Fischer Petra Ptschke Giesela Pompe Klaus-Jochen Eichhorn Heinz W. Siesler 《Macromolecular chemistry and physics.》1997,198(7):2057-2072
Rheo-optical Fourier transform infrared spectroscopy was used to analyze the orientational behavior of hard and soft segments of thermoplastic poly(ether urethane)s (TPU-Et) and poly(ester urethane)s (TPU-Es) and their blends with a 20 mass-% contribution of either polyethylene (PE) or polypropylene with an amorphous rubber phase (PP). The blends show a reduced stress level, lower elongation-to-break and a lower degree of orientation of the segments — especially for the TPU-Es blends — compared to those of pure TPU's when uniaxially elongated. Blends of TPU-Et with PP show reduced stress but increased strain compared to pure films of TPU-Et. This is caused by an improved adhesion of the rubber phase in the polypropylene and the polyether phase of TPU-Et. Optical micrographs visualize deformed polyolefin particles in elongated films of TPU-Et/PP blends. In the TPU-Et/PP blend we could achieve equivalent orientation for the polyolefin phase and the segments of TPU-Et caused by this higher phase adhesion compared to the other blends. Orientation functions (OF's) of absorption bands which specifically represent hard or soft polyurethane segments or which are characteristic of the polyolefin phase have been calculated to monitor the molecular alignment due to the mechanical treatment. 相似文献
9.
OBJECTIVES: The purpose of this study was to identify individual characteristics associated with types and frequency of milk consumption in older American adults. METHODS: A national probability-based sample (response rate = 91%) completed a telephone survey. Generalized logit and cumulative logit analyses were used to identify predictors of and barriers to fluid milk consumption in 494 elderly people. RESULTS: The likelihood of drinking skim or 1% milk rather than whole milk increased with nutrition knowledge, income, trying to reduce cholesterol intake, and being female (P < .05). Frequency of milk consumption was higher with nutrition knowledge, frequency of milk consumption during adolescence, and following a diabetic diet but was lower with milk intolerance. CONCLUSIONS: The present results could be used to develop intervention strategies for improving milk consumption rates among older adults. These strategies might focus on increasing elderly people's awareness of milk intolerance and lactose-reduced milk products and their concern about cholesterol. The relationship between current and adolescent milk consumption suggests that intervention strategies should begin early in life. 相似文献
10.
Mental illness and the continuum of residential stability 总被引:1,自引:0,他引:1