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101.
苏爱 《中国优生与遗传杂志》2004,12(3):43-44
目的与方法本文对189例自然流产、闭经、发育不全患者进行细胞遗传学检查,结果发现异常核型16例,异常核型涉及1、3、4、5、6、7、8、9、10、 15、X、Y染色体.其中平衡易位10例,性染色体异常3例,大Y染色体3例.结论染色体异常是导致流产、闭经、性发育异常的重要遗传因素,应引起临床医师的高度重视. 相似文献
102.
Van Kaer L 《Immunologic research》2004,30(2):139-153
Natural killer T (NKT) cells are a unique subset of T lymphocytes that share receptor structures and properties with conventional
T lymphocytes and natural killer (NK) cells. NKT cells are specific for glycolipid antigens such as the marine sponge-derived
agent α-galactosylceramide (α-GalCer) presented by the major histocompatibility complex (MHC) class I-like molcule CD1d. My
laboratory has evaluated the function of NKT cells by generating and analyzing CD1d-deficient mice. These studies showed that
CD1d expression is required for NKT cell development, but not absolutely necessary for the generation of polarized T helper
(Th) cell responses. Further, we have studied the in vivo response of NKT cells toα-GalCer stimulation and the capacity of
α-GalCer to modulate innate and adaptive immune responses. Our results revealed that, quickly following administration of
α-GalCer, NKT cells expand and produce cytokines, trans-activate a variety of innate and adaptive immune cells, and promote Th2 responses that are capable of suppressing Th1-dominant
autoimmunity. Our findings indicate that NKT cells play a regulatory role in the immune response and that specific activation
of these cells may be exploited for therapeutic purposes. 相似文献
103.
Evans DL Kaur H Leary J Praveen K Jaso-Friedmann L 《Developmental and comparative immunology》2005,29(12):1049-1064
Nonspecific cytotoxic cells (NCC) are the first identified and most extensively studied killer cell population in teleosts. NCC kill a wide variety of target cells including tumor cells, virally transformed cells and protozoan parasites. The present study identified a novel evolutionarily conserved oligodeoxynucleotide (ODN) binding membrane protein expressed by channel catfish (Ictalurus punctatus) NCC. Peptide fingerprinting analysis of the ODN binding protein (referred to as NCC cationic anti-microbial protein-1/ncamp-1) identified a peptide that was used to design degenerate primers. A catfish NCC cDNA library was used as template with these primers and the PCR-amplified product was sequenced. The translated sequence contained 203 amino acids (molecular mass of 22,064.63 Da) with characteristic lysine rich regions and a pI=pH 10.75. Sequence comparisons of this protein indicated similarity to zebrafish (51.2%) histone family member 1-X and (to a lesser extent) to trout H1. A search of EST databases confirmed that ncamp-1 is also expressed in various tissues of channel catfish as well as zebrafish. Inspection for signature repeats in ncamp-1 and comparisons with histone-like peptides from different species indicated the presence of multiple lysine based motifs composed of AKKA or PKK repeats. The novel protein was cloned, expressed in E. coli and the recombinant was used to generate rabbit anti-serum. The recombinant ncamp-1 bound GpC and CpG ODNs and was detected with homologous anti-ncamp-1 polyclonal antibodies. Western blots of NCC membranes using anti-ncamp-1 serum detected a 29 kDa protein. Binding competition experiments demonstrated that anti-ncamp-1 antibodies and GpC bound to the same protein on NCC. Two different truncated forms of ncamp-1 as well as the full-length recombinant protein exhibited anti-microbial activity. The present study demonstrated the expression by NCC of a new membrane protein that may participate in the recognition of bacterial DNA and as such participate in innate anti-microbial immune responses in teleosts. 相似文献
104.
Differential expression of human granzymes A, B, and K in natural killer cells and during CD8+ T cell differentiation in peripheral blood 总被引:5,自引:0,他引:5
Bratke K Kuepper M Bade B Virchow JC Luttmann W 《European journal of immunology》2005,35(9):2608-2616
NK cells and cytotoxic T lymphocytes can induce apoptosis in virus-infected and transformed target cells via the granule exocytosis pathway. The key components of the cytolytic granules are perforin and several serine esterases, termed granzymes. While the cellular distribution of human granzymes A (GrA) and B (GrB) has been well characterized much less is known about the expression pattern of human granzyme K (GrK). In this study GrA, GrB, and GrK expression was analyzed in human peripheral blood lymphocytes using flow cytometry. There was a distinct population of GrK expressing CD8+ T cells with a CD27+/CD28+/CCR5high/CCR7-/perforin-/low/IFN-gamma+ memory-like phenotype, while all CD56bright NK cells were also positive for GrK. In addition, GrK was also expressed in subpopulations of CD56+ T cells, CD4+ T cells, and TCRgammadelta+ T cells. In contrast, GrB was primarily expressed in CD56dim NK cells and differentiated memory CD8+ T cells with the CD27-/low/CD28-/low/CCR5-/low/CCR7-/CD11b+/perforinhigh phenotype. Only few CD8+ T cells expressed both GrB and GrK. GrA was found to be co-expressed in all GrB- and GrK-expressing T cells. Our findings suggest that granzyme expression during the differentiation process of memory CD8+ T cells might be as follows: GrA+/GrB-/GrK+ --> GrA+/GrB+/GrK+ --> GrA+/GrB+/GrK-. 相似文献
105.
Precipitation of fibrinogen, fibrinogen degradation products and fibrin monomer by histone H3 总被引:1,自引:0,他引:1
Incubation of histone H3 with normal citrated plasma resulted in the formation of insoluble aggregates, as determined by turbidity measurements. The precipitate was subjected to sodium dodecyl sulfate polyacrylamide gel electrophoresis, confirming that fibrinogen was a major component. Purified fibrinogen precipitated rapidly as determined with turbidity experiments and experiments with radioiodinated protein. The amount of fibrinogen precipitation was strongly dependent on H3 concentration. Variation of ionic strength (0.2-0.84) and pH (5.3-7.4), however, had little or no effect on the reaction. Fibrinogen subjected to gelatin-Sepharose chromatography or dialysis against 3.3M urea reacted equivalently with H3. Precipitation of 125I-fibrinogen by H3 was strongly favored by increasing temperature (4 degrees-45 degrees C). Precipitation of fibrinogen by protamine was maximized by decreasing the temperature. In addition, formation of insoluble fibrinogen-protamine aggregates was highly dependent on ionic strength and pH, suggesting that different types of protein-interaction are involved in the two studied precipitation reactions. Of the fibrinogen degradation products, only fragment X precipitated significantly when incubated with H3. Radioiodinated fibrin monomer also precipitated when incubated with H3 in solutions of sufficient ionic strength to prevent spontaneous polymerization. The extent of precipitation was equivalent for fibrin monomer and fibrinogen. Fragment D inhibited the precipitation of fibrinogen by H3 or protamine. These studies indicate that the proteins termed "paracoagulants" are not all equivalent and that the hydrophobic domain of H3 plays a critical role in fibrinogen precipitation. 相似文献
106.
目的:观察自由体位分娩对不同分娩方式的影响。方法:选取94例来我院分娩的孕产妇为研究对象,按入院顺序将其分为两组,采取常规卧位分娩的为对照组,应用自由体位分娩的则为观察组。对比两组产妇的产程时间及分娩方式。结果:①产程时间方面,两组产妇第二、第三产程时间差异不明显(P>0.05),但观察组第一及总产程时间显著低于对照组(P<0.05)。②分娩方式方面,观察组自然分娩率要显著高于对照组,剖宫产率明显低于对照组,P<0.05。结论:通过采取自由体位的方式进行分娩,可缩短产程,降低剖宫产率。 相似文献
107.
Fishery products are the main source of dietary n-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA). Following the European Commission’s request to address the risks and benefits of seafood consumption, and taking into account the great variability of nutrient and contaminant levels in fishery products, the present work aims to estimate the n-3 LC-PUFA provided per serving of selected fishes, shrimps and mollusks that are commonly consumed in Spain. This would enable the establishment of a risk–benefit analysis of fish consumption and provide recommendations for fish intake to comply with nutritional guidelines of n-3 LC-PUFA intake. We confirmed high variation in the pattern and contents of fatty acids for different species. n-6 PUFA were minor fatty acids, whereas palmitic (C16:0), oleic (C18:1 n-9), and mainly eicosapentaenoic (C20:5 n-3) and docosahexaenoic (C22:6 n-3) acids were the major fatty acids in the sample. Therefore, consumption of 2–3 servings per week of a variety of fishery products may contribute to compliance with the recommended daily n-3 LC-PUFA intake while maintaining an adequate balance to avoid contaminant-derived potential risks (metals and others). Taking the fatty acid content of fishery products described in this study into consideration, it is advisable to include one serving of fatty fish per week in order to meet recommended n-3 LC-PUFA levels. 相似文献
108.
Micha Oczkowski Katarzyna Dziendzikowska Anna Pasternak-Winiarska Dariusz Wodarek Joanna Gromadzka-Ostrowska 《Nutrients》2021,13(2)
Due to the constantly increasing number of cases, prostate cancer has become one of the most important health problems of modern societies. This review presents the current knowledge regarding the role of nutrients and foodstuff consumption in the etiology and development of prostate malignancies, including the potential mechanisms of action. The results of several in vivo and in vitro laboratory experiments as well as those reported by the clinical and epidemiological research studies carried out around the world were analyzed. The outcomes of these studies clearly show the influence of both nutrients and food products on the etiology and prevention of prostate cancer. Consumption of certain nutrients (saturated and trans fatty acids) and food products (e.g., processed meat products) leads to the disruption of prostate hormonal regulation, induction of oxidative stress and inflammation, and alteration of growth factor signaling and lipid metabolism, which all contribute to prostate carcinogenesis. On the other hand, a high consumption of vegetables, fruits, fish, and whole grain products exerts protective and/or therapeutic effects. Special bioactive functions are assigned to compounds such as flavonoids, stilbenes, and lycopene. Since the influence of nutrients and dietary pattern is a modifiable risk factor in the development and prevention of prostate cancer, awareness of the beneficial and harmful effects of individual food ingredients is of great importance in the global strategy against prostate cancer. 相似文献
109.
The aim of our research was to assess whether and to what extent the perceived change in the content of selected ingredients in dairy products is important for Polish consumers in accepting the enhancement of the health benefits of dairy products, including yogurt. The data were collected using a CAPI (Computer Assisted Personal Interview) survey on a sample of 983 consumers. The logistic regression model was used to predict the behavior of consumers associated with their willingness to accept the health aspects of improving dairy products. The results indicated that changes in the level of selected ingredients enhanced the willingness to accept increasing the health value of the product. The socio-demographic characteristics of the participants were not associated with the degree of their willingness to accept the improvement of the perceived health attributes. Practitioners in the dairy industry and policy makers can benefit from these results. When designing food products, it is worth focusing on increasing the nutritional value and enhancing the health value of food that is perceived by consumers as generally possessing positive health benefits, rather than on food that is perceived by them as possessing negative qualities. 相似文献
110.
通过分析临床科室取血工作量情况及2019年12602袋血液取发血的情况,对医院的输血科的位置选择提出建议。 相似文献