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101.
102.
BACKGROUND: Impaired implantation in assisted reproduction cycles with high serum estradiol (E(2)) concentrations may be related to suboptimal endometrial perfusion. Endometrial and subendometrial blood flow were compared between excessive responders (serum E(2) on the day of HCG >20 000 pmol/l) and moderate responders (E(2) < or =20 000 pmol/l). METHODS: Three-dimensional (3D) ultrasound examination with power Doppler was performed 2, 4 and 7 days after HCG in 32 patients who did not have embryo transfer in order to measure endometrial thickness, pulsatility index (PI)/resistance index (RI) of uterine vessels, and endometrial volume, vascularization index (VI)/flow index (FI)/vascularization flow index (VFI) of endometrial and subendometrial regions. RESULTS: Excessive responders tended to have lower endometrial and subendometrial VI/VFI on HCG +2 and more absent endometrial/subendometrial blood flow. They had significantly higher endometrial FI and subendometrial VFI than moderate responders on HCG +7. Only in the excessive responder group, uterine PI/RI declined significantly from HCG +2 to HCG +7 and endometrial VI/VFI increased significantly from HCG +4 to HCG +7. CONCLUSION: Changes in uterine Doppler flow indices, and endometrial and subendometrial 3D power Doppler flow indices during the early luteal phase were significantly different between moderate and excessive responders. 相似文献
103.
104.
Herein reported is a case of congenital malignant melanoma in a premature male baby from a 25-year-old healthy mother who was found to have hydramnios at the 29th week of gestation. The pregnancy was interrupted because of a large posterior neck mass detected by ultrasonography. The large neck mass of the baby was a malignant melanoma involving deep dermis and subcutaneous tissue. The skin over the mass showed a large area of pigmentation with hairs and the pigmentation involved the occipital scalp and posterior neck. Microscopically, the tumor cells were monotonous and showed polygonal and epithelioid appearance with prominent nucleoli indicative of malignant melanoma of a minimal deviation variety. Neither junctional components nor benign dermal nevus cells were noted. There were no distant metastasis or underlying leptomeningeal melanosis. This tumor is presumed to have developed from either preexisted congenital giant pigmented nevus with loss of benign components or de novo origin. 相似文献
105.
Cell-mediated immunity to proteoglycan antigens was assessed by leucocyte migration inhibition and by lymphocyte stimulation tests in patients with rheumatoid arthritis or with ankylosing spondylarthritis, in patients with relapsing synovitis after a single trauma to their knee joints, and in healthy donors. Both tests revealed a sensitization in most of the patients examined with various proteoglycan antigens derived from human cartilaginous tissues, rheumatoid synovial fluid, and species-common antigen of bovine nasal cartilage. Anybodies against proteoglycan antigens of human articular cartilage were detected by solid-phase radioimmunoassay in eleven out of twenty-nine sera from patients with rheumatoid arthritis and in four out of six rheumatoid synovial fluids. The results suggest that the cartilage antigenic components released by an inflammatory process or trauma may trigger a vicious circle of chronic inflammation and joint destruction. 相似文献
106.
评价用聚乙二醇系列的表面改性剂PEG、F127及PELA改性的纳米羟基磷灰石/聚乳酸复合材料的亲水性和溶胀性,先对纳米羟基磷灰石进行表面改性处理后,再综合用传统的溶液共混、流延法及热压法将改性的和未改性的纳米羟基磷灰石分别与聚乳酸制备成复合薄膜。检测结果表明:改性剂分别被涂敷于纳米羟基磷灰石上,改性处理能够改善纳米颗粒在基材内的分布;改性的纳米羟基磷灰石/聚乳酸复合材料比未改性的对比材料的表面接触角小、表面能大、亲水性好、溶胀度大,达到饱和溶胀度的时间长。改性的纳米羟基磷灰石比未改性的羟基磷灰石改善基体聚乳酸的亲水性和溶胀性效果更显著。 相似文献
107.
Prominent proliferative response of peripheral blood mononuclear cells to a recombinant non-structural (NS3) protein of hepatitis C virus in patients with chronic hepatitis C.
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P M Yang L H Hwang M Y Lai W L Huang Y D Chu W K Chi B L Chiang J H Kao P J Chen D S Chen 《Clinical and experimental immunology》1995,101(2):272-277
The proliferative response of peripheral blood mononuclear cells (PBMC) to a recombinant non-structural (NS3) protein of hepatitis C virus (HCV) was studied in 41 patients with chronic hepatitis C. Of them, 28 had chronic persistent hepatitis (CPH) and 13 chronic active hepatitis (CAH). The positive proliferation rate of PBMC to the recombinant NS3 protein, T9Ag, was 66% in the 41 patients (77% in CAH versus 61% in CPH; P > 0.05) when stimulation index (SI) = 4 was set as the cut-off value. However, mean SI of CAH patients was significantly higher than that of CPH patients (8.3 +/- 5.2 versus 5.1 +/- 3.6; P < 0.05). Six other chronic hepatitis patients who were repeatedly negative for anti-HCV antibody but positive for serum HCV RNA also had an SI of > or = 4.0. The frequency of cellular immune response to the T9Ag is among the highest results obtained by using HCV antigens tested so far. Our studies thus indicate that NS3 is an immunologically important region of HCV for T cells. Moreover, the proliferative response to T9Ag may help to establish hepatitis C etiology in chronic hepatitis patients who are seronegative with currently available anti-HCV assays. 相似文献
108.
B B Chomel R W Kasten K Floyd-Hawkins B Chi K Yamamoto J Roberts-Wilson A N Gurfield R C Abbott N C Pedersen J E Koehler 《Journal of clinical microbiology》1996,34(8):1952-1956
Bartonella henselae is an emerging bacterial pathogen, causing cat scratch disease and bacillary angiomatosis. Cats bacteremic with B. henselae constitute a large reservoir from which humans become infected. Prevention of human infection depends on elucidation of the natural history and means of feline infection. We studied 47 cattery cats in a private home for 12 months to determine the longitudinal prevalence of B. henselae bacteremia, the prevalence of B. henselae in the fleas infesting these cats, and whether B. henselae is transmitted experimentally to cats via fleas. Vector-mediated transmission of B.henselae isolates was evaluated by removing fleas from the naturally bacteremic, flea-infested cattery cats and transferring these fleas to specific-pathogen-free (SPF) kittens housed in a controlled, arthropod-free University Animal Facility. B. henselae bacteremia was detected in 89% of the 47 naturally infected cattery cats. A total of 132 fleas were removed from cats whose blood was simultaneously cultured during different seasons and were tested individually for the presence of B. henselae DNA by PCR. B. henselae DNA was detected in 34% of 132 fleas, with seasonal variation, but without an association between the presence or the level of bacteremia in the corresponding cat. Cat fleas removed from bacteremic cattery cats transmitted B. henselae to five SPF kittens in two separate experiments; however, control SPF kittens housed with highly bacteremic kittens in the absence of fleas did not become infected. These data demonstrate that the cat flea readily transmits B. henselae to cats. Control of feline infestation with this arthropod vector may provide an important strategy for the prevention of infection of both humans and cats. 相似文献
109.
Lee CH Lee MK Kang CD Kim YD Park DY Kim JY Sol MY Suh KS 《Journal of Korean medical science》2003,18(2):196-203
This study aimed to evaluate whether the elevated level of hypoxia-inducible factor-1alpha (HIF-1alpha) correlated with histologic types, angiogenesis, tumor cell proliferation, and clinical parameters in common non-small cell lung carcinomas (NSCLCs). We performed immunohistochemical stains using paraffin-embedded tissue blocks from 84 cases of operable NSCLC [No. of squamous cell carcinoma (SCC), 45; No. of adenocarcinoma (AC), 39]. HIF-1alpha expression was related with histologic types (66.7% in SCCs vs 20.5% in ACs, p<0.001), but not with lymph node status, tumor stage, vascular endothelial growth factor expression, microvessel density (MVD), and proliferating cell nuclear antigen (PCNA) index (p>0.05, respectively). As for the histologic types, MVD and PCNA index were significantly higher in SCCs than in ACs (p=0.009 and p=0.016, respectively). Among HIF-1alpha positive carcinomas, MVD was significantly higher in HIF-1alpha positive SCCs than in HIF-1alpha positive ACs (p=0.023). The overall survival curves were not associated with HIF-1alpha expression or any other histologic parameters (p>0.05). These findings suggest that HIF-1alpha expression in NSCLCs may play a differential role according to histologic types, but its prognostic significance is indeterminate. 相似文献
110.
Carbohydrate tumor-antigens are important tumor markers for diagnosis and functional characteristics of human cancer cells. Detection of these carbohydrate tumor antigens on metastatic cancer cells in blood is a difficult task. We developed a highly sensitive method to detect a cell surface carbohydrate antigen using a hybrid technology referred to as cellular immuno-PCR. This technique uses the human monoclonal antibody (HumAb) L612, specific to a tumor-related antigen (ganglioside) GM3 that is expressed on the cell surface of human tumor cells and not normal cells. L612 coupled to a DNA oligonucleotide for exponential amplification by DNA polymerase chain reaction (PCR) can be used to enhance the detection signal. The DNA-HumAb conjugate was assessed for detection of a small number of human cancer cells after PCR amplification and Southern blot analysis. To assess the assay specificity human melanoma and other cancer cell lines, as well as healthy donor and melanoma patients, bloods were assessed. Cellular immuno-PCR requires < 1 ng/ml DNA-HumAb complex and was shown to have a detection level of < 10 cells in titration studies in which melanoma cells were diluted in 2 million healthy donor peripheral blood lymphocytes. The assay was shown to be very sensitive and could detect low levels of GM3 antigen expression by tumor cells. This novel approach for detecting a carbohydrate tumor antigen on tumor cells in blood provides a potential useful clinicopathological assay. 相似文献