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111.
Guidelines for the appropriate use of genetic tests in infertile couples   总被引:10,自引:0,他引:10  
Research on genetic causes of male and female infertility rapidly expanded in the last years, following the development of in vitro fertilising techniques. Genetic tests are now available to explore the cause of the infertility and assess the risk of a given couple to transmit its genetic characteristics. This allows at-risk couples to take an informed decision when electing for a medically assisted reproduction. It also allows the professionals to offer a prenatal diagnosis when appropriate. Thus, the genetic work-up of the infertile couple has become good practice for an appropriate diagnosis, treatment and prognostic assessment. The lack of national or international rules for the genetic approach to the infertile couple, prompted the Italian community of professionals in the field of reproductive medicine to join and set up guidelines for the genetic diagnosis of male and female infertility. The group of clinical and research experts is representative of 12 national scientific societies and was supported by external experts from four international societies. We examine the clinically relevant genetic causes of male and female infertility and suggest the category of patients for which each genetic test is recommended or optional, both for an accurate diagnosis and prior to ART.  相似文献   
112.
Russo  A.; Tommasi  A.M.; Renzi  L. 《Mutagenesis》1996,11(6):547-552
A protocol for the simultaneous visualization of minor and majorsatellite DNA by primed in situ DNA synthesis PRINS was developedin cytokinesis–blocked murine splenocytes. After individuationof optimal experimental conditions, a micronucleus MN test wascarried out by treating splenocytes in vitro with the clastogenicagent mitomycin C and the aneugenic compound Colcemid. It wasfound that PRINS gives highly reproducible results, also comparablewith the literature on MN results obtained by fluorescent insitu hybridization FISH. Therefore the PRINS methodology maybe proposed as a fast alternative to FISH for the characterizationof induced MN. 1To whom correspondence should be addressed  相似文献   
113.
In this study we present a new case of Factor XIII deficiency. The proposita, a 34 year old woman, showed a deficiency of both subunit a and subunit b, and a moderate bleeding tendency. Because of the concomitant decrease of subunits a and b the proposita is considered to be an example of Type I disease. Factor XIII levels were less than 10% both as activity and antigen. Several family members showed intermediate levels of both subunit a and b and were asymptomatic. They were considered to be heterozygotes. The hereditary pattern is autosomal incompletely recessive. Type I disease appears much less frequent than Type II.  相似文献   
114.
The dual role of IL-10   总被引:20,自引:0,他引:20  
Classification of cytokines as pro-versus anti-inflammatory might not apply to the pleiotropic effects of interleukin-10 (IL-10). Several reports suggest that IL-10 enhances the function of natural killer cells, which leads, through pathogen destruction, to increased antigen availability. In addition, by inhibiting the maturation of antigen-presenting cells (APCs), IL-10 preserves their ability for antigen uptake while simultaneously hampering their migration to draining lymph nodes. This review suggests that this "antigen-loading" phase might constitute an important component of the innate immune reaction to a pathogen. Additional proinflammatory stimuli might subsequently lead to maturation of "loaded" APCs that could migrate to draining lymph nodes or recruit and activate adaptive immune effectors locally.  相似文献   
115.
116.
Phagocytosis by Botryllus schlosseri hemocytes in influenced by temperature, pH, concentration, and physicochemical properties of the test particles and requires Ca2+ or Mg2+ ions to occur. Phagocytes recognized glucosyl or mannosyl residues on the surface of yeast cells, and a respiratory burst is associated with phagocytosis, as indicated by increased superoxide production. Factors that enhance phagocytosis of yeast, sheep red blood cells, and latex beads and reduce the uptake of yeast and sheep erythrocytes are present in the plasma.  相似文献   
117.
Molecular biology techniques have given novel impetus to the immunotherapy of cancer because they have catalyzed the identification of several potential tumor antigens, and permitted the generation of vectors for the delivery of genetic material encoding these antigens. Vaccines can be defined "genetic" when the antigen they enclose is present as DNA or RNA. Microrganisms used as vectors can deliver the genetic information, but naked nucleic acids have also been shown to be effective immunogens thanks to built-in adjuvants that activate professional antigen presenting cells. Although gene-based cancer vaccines have been tested in mouse models and selected for pilot clinical trials, enthusiasm has somewhat waned due to an apparently major drawback of cancer vaccination: tumor antigens are weak, and therefore fail to stimulate a sterilizing immune response in tumor-bearing patients. Mouse studies, however, have shown that cancer vaccines are extremely efficacious in establishing a state of active immunosurvellance against tumor growth. This review reconsiders the findings emerging from preclinical studies in the context of our current knowledge of the cellular and molecular bases of the immune responses to vaccines, in an attempt to approach critically the use of genetic vaccination for the treatment of cancer.  相似文献   
118.
BACKGROUND: People's reactions to traumatic events are mediated by their subjective style of coping. This is of particular importance for HIV+ patients, mainly in the first phases of the disease. This work aimed at examining whether an 'acceptance' style of coping, as opposed to a 'mental disengagement' style, selectively influences the first stages of the processing of neutral, emotional and HIV-related information. METHOD: Two groups of 11 HIV+ asymptomatic subjects were chosen according to their coping strategies, acceptance or mental disengagement, as measured by Coping Orientations to the Problems Experienced (COPE). Twenty-two patients completed the Emotional Stroop Task and an incidental memory recognition task containing neutral, emotional and HIV-related stimuli. RESULTS: Analysis of reaction times (RTs) on the Emotional Stroop Task showed that HIV+ subjects have longer RTs for emotional and HIV-related than for neutral words. Instead, no effect was found as regards interaction with style of coping. CONCLUSION: Results confirmed a processing bias of emotional information, whereas Acceptance and Mental disengagement strategies, as measured by the COPE scales, did not appear to influence information processing.  相似文献   
119.
Byusing a polyclonal antibody raised against smooth muscle MyosinLight Chain Kinase of adult chicken we show that the 135 kDasmooth muscle Myosin Light Chain Kinase isoform is present inneonatal and regenerating rat skeletal muscle, as well as inadult atrial myocardium. No reaction was evident in adultskeletal muscle fibres. In neonatal and in early regeneratingmuscle smooth muscle Myosin Light Chain Kinase is associated withembryonic myosin as revealed by their co-presence in musclefibres. Experiments in vitro show the same results in myotubes.In atrial myocardium there is a patchy positivity in certaingroup of myocytes. Immunoblotting experiments show in muscle cellcultures, in neonatal and in regenerating skeletal muscle aprotein band with electrophoretic mobility corresponding to thatof smooth muscle Myosin Light Chain Kinase. These results suggestthat the expression of smooth muscle Myosin Light Chain Kinase isnot fully tissue-specific and that regulation of the contractilemachinery could be different during myogenesis and in adulthood,in relation to the peculiar dynamic characteristics of developingmuscles  相似文献   
120.
The sensitivity to inactivation by ultraviolet light of the PB 1 strain of herpesvirus of turkeys (HVT) was determined and compared with the relative sensitivity of pseudo-rabies virus (PRV), another member of the herpesvirus group. HVT (PB1) was 6.3 times more resistant than PRV when assayed in chick embryo fibroblasts. The survival curve of HVT (strain PB1) had one component and the survival curve of PRV had two components. Survival curves of HVT and PRV in chick embryo fibroblasts treated with caffeine and in duck embryo fibroblasts are also presented. Evidence was obtained for host cell reactivation of HVT and PRV in chick embryo fibroblasts. Multiplicity reactivation could be clearly demonstrated for UV-irradiated PRV, but not for HVT.  相似文献   
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