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排序方式: 共有1203条查询结果,搜索用时 15 毫秒
1.
E. Weimann G. Reisbach J. Reinsberg M. J. Lentze 《Archives of gynecology and obstetrics》1995,256(3):125-130
Activity levels of cytokines were measured by stimulation of the cell lines NFS-60, 7TD1, and TF-1. In 39 samples of amniotic fluid, levels of Granulocyte-Stimulating Factor (G-CSF) were 1434±2063 (mean±SD) and of Interleukin (IL-6) 546±1071 pg/ml; Granulocyte-Macrophage Colony Stimulating Factor (GM-CSF) was not detectable. IL-6 was correlated to G-CSF (r=0.3; p=0.003). G-CSF (p=0.0002) and IL-6 (p=0.006) were influenced by Alpha-Fetoprotein (AFP) and G-CSF by rhesus-incompatibility (p=0.0004). These findings suggest that cytokines such as IL-6 and G-CSF play some role in physiological and pathological pregnancy.Abbreviations G-CSF
granulocyte-colony stimulating factor
- GM-CSF
granulocyte-macrophage colony stimulating factor
- M-CSF
macrophage-colony stimulating factor
- CSF
colonystimulating factor
- IL-6
interleukin-6
- IL-11
interleukin-11
- AFP
alpha-fetoprotein
- NFS-60
cell line
- 7TD1
cell line
- TF-l
cell line
- rh
recombinant human
- MTT
3-(4,5-dimethylthiazol2-yl)-2,5-diphenyl tetrazolium bromide
- FCS
fetal calf serum
- RPMI 1640
nutrient solution
- ATCC
American Tissue Culture Collection
Correspondence to: E. Weimann 相似文献
2.
乙型肝炎甲胎蛋白检测与重型肝炎预后指数评估的意义 总被引:1,自引:0,他引:1
给慢性活动肝炎患者输注人胎肝细胞悬液引起血清甲胎蛋白增高反应的初浓度为202±38.3μg/L,其半衰期为1.7天;分布池为6.9一10.2升。重型肝炎生存组血清甲胎蛋白显著高于死亡组,生存组甲胎蛋白与血清总胆红素呈非常显著相关,而死亡组两者无相关性。重型肝炎患者输注胎肝悬液后其血清甲胎蛋白进一步升高者,预后较好。取重型肝炎预后指数0.1为重型肝炎生死的截断点,判断预后的灵敏度、特异度、准确度和阳性预告值分别为79.5%、89.6%、84.8%和87.5%。重型肝炎预后指数的计算可作为判断预后与新疗法疗效的指标。 相似文献
3.
F. Jaisser J. D. Horisberger B. C. Rossier 《Pflügers Archiv : European journal of physiology》1993,425(5-6):446-452
The cortical collecting tubule (CCT) of the mammalian kidney reabsorbs sodium and potassium, processes that are mediated by Na/K-ATPase and H/K-ATPase. CCT is also an important site for proton secretion, which is driven, in part, by H/K-ATPase. Na/K-ATPase and H/K-ATPase are members of the ion-motive P-ATPase gene family. They are closely related plasma membrane proteins which consist of heterodimers. The urinary bladder of the toad Bufo marinus is the amphibian counterpart of mammalian CCT. We have previously characterized a ouabain-resistant Na/K-ATPase [see ref. 17], from TBM cells, a clonal cell line derived from the toad bladder, which expresses transepithelial sodium transport. In the present study, we report the primary sequence and functional expression of a novel subunit (
bladder=
bl) isolated from a toad bladder epithelial cell cDNA library. The deduced polypeptide is 299 amino acids in length and has a predicted molecular mass of 33 kDa. The
bl protein exhibits 35% amino acid identity to the previously characterized
1 of B. marinus Na/K-ATPase and 39% identity with
3 of B. marinus Na/K-ATPase. It shares 38% identity with the mammalian gastric H/K-ATPase and 52% with the mammalian
2 Na/K-ATPase. Northern blot analysis shows that a 1.4×103-base mRNA is expressed at a high level in bladder epithelial cells and eye and at a trace level in kidney; it is not detectable in significant amounts in the stomach, colon and small intestine. The
bl subunit can associate with the
1 subunit of B. marinus Na/K-ATPase to form a functional sodium pump in the Xenopus laevis oocyte. Our data indicate that, in addition to the known
1 and
3 isoforms, a third distinct isoform of the subunit is present in the bladder epithelium. This new isoform could be functionally associated with subunits of either Na/K- or H/K-ATPase. 相似文献
4.
K.-M. Zhang Ping Hu Shang-Wu Wang Leon D. Wright Andrew S. Wechsler John A. Spratt F. N. Briggs 《Pflügers Archiv : European journal of physiology》1997,433(6):766-772
Using an immunohistochemical double-labeling technique, we observed that different isoforms of sarcoplasmic reticulum Ca-ATPase
are co-expressed in single fibers of canine fast-twitch skeletal muscles stimulated chronically at low frequency. By 7 days
of neuromuscular stimulation, the population of hybrid fibers expressing both SERCA1 and SERCA2a [fast- and slow-twitch isoforms
of sarco(endo)plasmic reticulum Ca2+-ATPase] had increased from 1.5% to 9.2% of fibers. By 14 days of stimulation 90% of the pure fast-twitch fibers (expressing
only SERCA1) were replaced by hybrid fibers. An additional 28 days of stimulation caused all fast-twitch fibers to express
SERCA2a at the same level as found in nonstimulated slow-twitch fibers (expressing only SERCA2a). At this time, one-half of
the previously hybrid fibers had become pure slow-twitch fibers. The remaining one-half of the hybrid fibers expressed SERCA1
at a very low level. Extending stimulation to 70 days did not further change the percentage of fibers that were slow-twitch
or hybrid. Immunoblot studies at the whole-muscle level confirmed that changes in SERCA expression at 42 days of neuromuscular
stimulation were complete. Immunohistochemical analysis of longitudinal sections of muscle showed that the changes in SERCA
protein were uniform along the length of the muscle fiber, indicating that nuclei along its length responded equally to chronic
stimulation.
Received: 12 November 1996 / Received after revision and accepted: 16 December 1996 相似文献
5.
6.
Here we have investigated and compared the effects of anti-CD4 on helper function of CD4,45RA+ versus CD4,45RO+ T cells. Only CD4,45RO+ cells, but not CD4,45RA+ cells were able to promote B cell differentiation resulting in immunoglobulin production in vitro (IgM as well as IgG) which could be inhibited by anti-CD4 MoAbs (MAX.16H5 and T151). In pokeweed mitogen (PWM)-induced B cell proliferation a similar pattern of responsiveness was obtained. When we studied the anti-CD4 effects on cytokine production in T cells stimulated in mixed lymphocyte reaction (MLR) or by mitogens, we found that neither IL-2 nor IL-4 production was dramatically influenced by anti-CD4 in CD4,45RO+ cells. This led us to the conclusion that the inhibitory effect of anti-CD4 on B cell proliferation and immunoglobulin secretion was not due to inhibition of cytokine production. To clarify this point, we investigated the ability of anti-CD4 to inhibit conjugate formation between B and T cells. It was found that CD4,45RO+ T cells formed more conjugates than CD4,45RA+ cells, and that only the conjugate formation by CD4,45RO+ T cells was inhibited by anti-CD4. These results suggest that (i) anti-CD4 inhibits T helper functions primarily by affecting CD4,45RO+ cells, and (ii) this effect is probably mediated by contact inhibition in the early phase of T-B collaboration. 相似文献
7.
M Rosario Sepúlveda Matias Hidalgo-Sánchez Daniel Marcos Ana M Mata 《Developmental dynamics》2007,236(5):1227-1236
The plasma membrane Ca(2+)-ATPase (PMCA) is highly expressed in the nervous system, but little information is available about its implication in neuronal development. We have analyzed the expression and localization of different isoforms of PMCA in membrane vesicles and sections of chick cerebellum from embryonic day 10 to hatching. We found that the relative amount of each PMCA isoform and their spatiotemporal distribution in the cerebellum are directly linked to precise cellular types during the cerebellar maturation, even in a non-neural tissue as choroid plexus. Purkinje cells contain the highest diversity of PMCA isoforms of the cerebellar cortex since the moment of its morphogenesis. From embryonic day 15, the PMCA2 was highly expressed in the whole Purkinje cell, while PMCAs 1 and 3 had a more restricted distribution in the soma and dendritic branches, and these distributions were evolving according with cell maturation. Other cellular types seem to contain a specific combination of isoforms, but with a well-defined distribution pattern at late moments of development. Thus, PMCAs 1 and 3 were located in the soma of molecular layer interneurons, and only the PMCA2 was observed in granule cells at hatching. Furthermore, PMCA isoforms are also expressed in cellular compartments characterized by a high amount of synapses, suggesting a key role of these proteins in synaptogenesis and in the maturation of neuronal electrophysiological properties. 相似文献
8.
Paolo Leoncini Marcella Cintorino Carla Vindigni Lorenzo Leoncini Doretta Armellini Massimo Bugnoli Omar Skalli Giulio Gabbiani 《Virchows Archiv : an international journal of pathology》1988,412(4):329-337
Summary We have evaluated by means of immunocytochemistry the distribution of various cytoskeletal and contractile proteins (cytokeratins, vimentin, desmin and -smooth muscle actin) in 23 salivary or lacrimal gland primary tumours (15 pleomorphic adenomas and 8 carcinomas in pleomorphic adenoma), one third of which contained areas of normal gland. Normal epithelial luminal cells were stained by cytokeratin antibodies with a general specificity, while myoepithelial cells were selectively stained by a monoclonal antibody (SK2-27) reacting in immunoblots with cytokeratin polypeptides 14, 16 and 17, according to the classification of Moll et al. (1982) and by an antibody directed against -smooth muscle actin (Skalli et al. 1986). In pleomorphic adenomas, both epithelial and myoepithelial cells displayed typical topographic distributions; moreover, myoepithelial cells showed two distinct cytoskeletal phenotypes. These findings could account in part for the heterogeneity of aspects observed in this tumour. In carcinomas, malignant cells were always positive to cytokeratin antibodies with general specificity and myoepithelial cells were absent as judged by anticytokeratin SK2-27 and anti--smooth muscle actin immunostainings. However, interestingly, there was in all cases a strong positivity for -smooth muscle actin in stromal cells, similarly to what has previously been described for mammary carcinoma (Skalli et al. 1986). Our findings may be useful for the interpretation of the histogenesis of salivary and lacrimal tumour and stromal cells. 相似文献
9.
Campino C Torres C Ampuero S Díaz S González GB Serón-Ferré M 《Human reproduction (Oxford, England)》1999,14(4):898-905
To assess whether plasma prolactin (PRL) characteristics relate to lactogenesis and absence or presence of menstrual cycles, we measured bioactive PRL (BIO-PRL) using the Nb2 assay, immunoreactive PRL (IR-PRL) by radio-immunoassay, calculated equations describing the BIO-PRL-IR-PRL relationship and separated charged PRL isoforms (by chromatofocusing) in five amenorrhoeic and five cycling nursing women at 6 months postpartum and in 10 cycling non-nursing women. Plasma samples were drawn before and 30 min after a suckling episode at 0800, 1600 and 2400 h in nursing women and at the same hours in non-nursing women. BIO-PRL and IR-PRL concentrations were highest in amenorrhoeic nursing women, intermediate in cycling nursing women and lowest in cycling non-nursing women. The BIO-PRL-IR-PRL relationship shows that a given amount of IR-PRL corresponds to equivalent amounts of BIO-PRL in cycling nursing and cycling non-nursing women, and to a larger extent in amenorrhoeic nursing women. IR-PRL was present in plasma as several charge isoforms. Bioactive isoforms eluting at pH 6.0-5.1 were found in amenorrhoeic and cycling nursing women, reaching similar concentrations after suckling. Bioactive isoforms eluting at pH 7.0-6.1 were found only in amenorrhoeic nursing women. We speculate that isoforms eluting at pH 6.0-5.1 may play a role in lactation and isoforms eluting at pH 7.0-6.1, in lactational amenorrhoea. 相似文献
10.