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21.
The concept of antiphospholipid syndrome(APS) has been widely accepted. Antiphospholipid antibodies originally included anticardiolipin antibodies and lupus anticoagulants as serological marker of APS. However, recent advances have shown that most pathogenic antiphospholipid antibodies are directed to phospholipid binding proteins such as beta 2-glycoprotein I and prothrombin as well as phospholipids. The preliminary classification criteria for definite APS have been advocated as the "Sapporo criteria". Further prospective investigations are required to re-evaluate the clinical significance of so-called antiphospholipid antibodies.  相似文献   
22.
In spite of the widespread use of assisted reproductive technology, there have been, to our knowledge, only two reported cases of molar pregnancies after gamete intra-Fallopian transfer and five reported cases after in-vitro fertilization and embryo transfer. We report here a case of a complete hydatidiform mole in a twin pregnancy after gamete intra-Fallopian transfer, as well as a case of a complete hydatidiform mole in a triplet pregnancy after in-vitro fertilization and embryo transfer. The genetic constitution of each conceptus was determined by examination of the restriction fragment length polymorphism of the DNA with four different single-locus probes. This analysis revealed that both hydatidiform moles were of androgenetic origin and probably of monospermic origin. Moreover, the analysis confirmed that the pregnancies were dizygotic and trizygotic pregnancies respectively. The diagnostic utility of the analysis of DNA polymorphism is discussed in cases of a molar pregnancy with coexisting fetuses.   相似文献   
23.
The case to be reported is that of a 72-year-old woman with isolated adrenocorticotropic hormone (ACTH) deficiency, who complained of anorexia and generalized malaise. The secretions of human growth hormone(HGH), prolactin (PRL), luteinizing hormone (LH), follicle stimulating hormone (FSH), and thyroid stimulating hormone (TSH) were all within normal limit. In spite of the extremely low level of Cortisol, the plasma level of AGTH would not rise sufficiently, but a marked response of Cortisol to AGTH stimulation was recognizaed. The postmortem examination revealed a decrease In basophilic or PAS-positive cells of the anterior pituitary gland which also showed a selective loss of AGTH-secreting cells over immunohistochemical study. Electron microscope could easily visualize somatotroph, mammotroph, thyrotroph, FSH- and LH-gonadtroph, but corticotroph was difficult to be discerned. Adrenocortical cells demonstrated atrophy and degeneration, for which the zona fasciculata and zona reticularis were narrowed. The zona glomerulosa was slightly enlarged In width.  相似文献   
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We studied promoter region polymorphisms in the interleukin (IL)-1alpha, IL-1beta, IL-6, IL-10, tumor necrosis factor, and transforming growth factor (TGF)-beta1 genes in Japanese patients with Alzheimer's disease (AD) (n = 172) and normal controls (n = 163). We also examined an association of a polymorphism located in the glutathione S-transferase omega 1 (GSTO-1) gene region with AD patients. None of these genotypes or allele frequencies showed a significant difference between AD patients and controls. We also failed to detect any difference in the disease onset between each genotype of the seven polymorphisms. Although AD patients carrying high producer alleles of TGF-beta1 and IL-1beta or TGF-beta1 and IL-6 showed a tendency for an early onset of the disease, neither of these combined effects reached a significant level after multiple comparisons. Our findings suggest that genetic polymorphisms in the cytokines and GSTO do not play a major role in Japanese AD patients.  相似文献   
26.
Yamaguchi I  Itoh S  Suzuki M  Sakane M  Osaka A  Tanaka J 《Biomaterials》2003,24(12):2031-2036
Crystalline chitosan was prepared from crab tendon consisting mainly of chitin, including various proteins and calcium phosphates. The crab tendon has high mechanical properties due to its aligned molecular structure. Crab tendon components, i.e. proteins and calcium phosphates, were removed by deacetyl treatment using 50wt% NaOH aqueous solution at 100 degrees C, and a subsequent ethanol treatment. As judged from microscopic observations using an optical polarizer, the treated chitosan remained intact regarding its aligned molecular structure, and had a high tensile strength of 67.9+/-11.4MPa. The tensile strength was further enhanced to 235+/-30MPa by a thermal treatment at 120 degrees C, corresponding to the formation of the intermolecular hydrogen bonds.  相似文献   
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Several functional subclones of rat anterior pituitary cells were established from our 2A8 clone which apparently contains a heterogeneous population of committed and uncommitted cells. On the basis of the hormones secreted into the culture media, as measured by radioimmunoassay, these subclones were divided into four categories, i.e., subclones which secrete (1) ACTH only, (2) prolactin only, (3) prolactin and GH or (4) ACTH, prolactin and GH. None of the subclones produced detectable amounts of thyrotrophic or gonadotrophic hormones. Subclones which secrete a single hormone have shown no change in the type of hormone produced, indicating that these subclones were each derived from a committed cell. The cells of all subclones exhibit a normal diploid karyotype and show good growth characteristics. The cells of the different subclones can be classified by phase contrast microscopy into four categories. However, no clear-cut ultrastructural features have been observed which can be correlated with the different categories of subclones. On the basis of the results a hypothesis is proposed relative to the functional cytodifferentiation of anterior pituitary cells.  相似文献   
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30.
Secretory role for human uterodomes (pinopods): secretion of LIF   总被引:5,自引:0,他引:5  
The differentiation of human endometrial epithelium is a dynamic event, which occurs throughout the menstrual cycle in preparation for pregnancy. The appearance of uterodomes (pinopods) in this regard was first introduced in rodents with an established pinocytotic function, whereas little evidence was available in humans in this context. This study was undertaken to identify the potential physiological roles of uterodomes in the implantation process. To address this, endometrial biopsies from early, mid- and late luteal phases of the menstrual cycle of 23 fertile female patients with regular menses were used. Scanning and transmission electron microscopies (SEM and TEM) as well as immunofluorescence and immunogold TEM were performed to study the morphological changes and the expression pattern of leukaemia inhibitory factor (LIF) at uterodomes. Our results illustrated a high level of LIF expression in the human uterodomes, which was colocalized with the well-known biochemical markers of exocytosis, including syntaxin-1, 25-kDa synaptosomal protein (SNAP-25) and vesicle-associated membrane protein-2 (VAMP-2). Our morphological and immunocytochemical findings illustrated a secretory function for human uterodomes for the first time. In conclusion, this novel function for uterodomes provides an important clue in detection of their physiological function(s) during the process of the plasma membrane transformation.  相似文献   
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