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991.
CONTEXT: The human endometrium acquires the ability to allow embryo attachment just for a specific period of time during each menstrual cycle. Understanding of the opposite functional status, referred to as refractoriness, can potentially be used to improve receptivity in infertile patients or as an interceptive approach to prevent gestation. OBJECTIVE: The objective of the study was to analyze the endometrial gene expression profile induced by an inert intrauterine device (IUD) at the time of implantation. DESIGN: We used a microarray containing more than 16,000 cDNAs to investigate the gene expression profile of receptive vs. refractory endometrium in the same women induced by the presence of an IUD. We compared the gene expression profile of endometrium obtained at LH+7 (window of receptivity) from the same women (n = 5) at the following time points: month 1, corresponding to the natural cycle before IUD insertion; month 3, just before IUD removal; and months 5 and 15. Data were validated by quantitative RT-PCR for IGF binding protein-3, peroxisome proliferative activated receptor-gamma, glycodelin, and leukemia inhibitory factor and immunohistochemistry for glycodelin. RESULTS: We identified 147 genes significantly dysregulated in the refractory endometrium (78 up- and 69 down-regulated). Interestingly, 52 of these genes have previously been reported to be regulated during window of implantation. Surprisingly, the majority of genes (96.6%) remained dysregulated 2 months after IUD removal, but 1 yr later most of them (80%) returned to normal. CONCLUSIONS: Our results reveal that a refractory endometrium in a fertile woman produced by an IUD is induced by preventing the normal transition to a receptive gene expression profile through effects on a specific subset or cluster of genes that impact on endometrial receptivity.  相似文献   
992.
Efficacy and safety of high and low molecular weight hyaluronates in knee osteoarthritis patients were compared in a randomized, open-label trial. Patients in the high molecular weight hyaluronate group were treated once weekly for 3 weeks and in the low molecular weight group once weekly for 5 weeks. We evaluated weight-bearing pain, degree of flexion, swelling and knee tenderness; frequency and amount of rescue medication; patient and investigator global assessment of pain, and safety over 12 weeks after final injection of study medication. Significant improvements in pain and WOMAC-Likert scores were observed in both groups, but not between groups. Knee joint pain improvement was noted in both groups by patients and investigators during follow-up. Close correlation was observed between patient- and investigator-reported data. There was no significant difference in side-effects between the groups. In conclusion, the efficacy and safety of high and low molecular weight hyaluronate are similar.  相似文献   
993.
We used a previously validated questionnaire survey, which was translated into Korean and given to 270 students from a university-based nursing school in Seoul. A total of 202 questionnaires were received. The students' hand dermatitis prevalence ranged from 6.9% in the first year to 22.9% in the fourth year. Logistic regression indicated that students with systemic allergies were 4.2 times as likely to suffer from hand dermatitis. Year of study and living arrangements were also shown to have statistically significant correlations with hand dermatitis. Overall, this study suggests that hand dermatitis might be less prevalent among Korean nursing students when compared with their international counterparts. However, the identification of systemic allergies as a significant risk factor was consistent with previous reports from other countries.  相似文献   
994.
A case of a 24-year-old woman with a 6 weeks lasting nodule of the right margin of the tongue is described. The nodule was 20 mm in diameter and showed surface ulceration. The diagnosis of low grade myofibroblastic sarcoma was supported by histological, immunohistochemical and electronmicroscopic examination. Although the tumor resection was not complete, the patient is free of disease 1 year after operation. The differential diagnostics of low grade myofibroblastic sarcoma is discussed.  相似文献   
995.
Aesthetics in implantology is a topic currently attracting lot of attention from dental implantologists all over the world. It includes both white and red aesthetics with much greater importance been given to the red aesthetics. In this article, both hard tissue and soft tissue procedures and techniques, used in the development of implant recipient sites will be presented and discussed, briefly outlining the treatment planning and also various dental materials used in enhancing aesthetics in implant restorative procedures.  相似文献   
996.
Subantral augmentation (sinus lift) is used to increase alveolar bone mass of lateral maxilla in order to insert dental implants. In addition to the autogenous bone several foreign materials can be used for augmentation and they can replace the autogenous bone to some extent. Histological findings in specimens taken nine months after augmentation with the autogenous bone, deproteinised bovine bone (Bio-Oss) and beta-tricalcium phosphate (Cerasorb) are presented. In all cases a new bone formation around the augmentation material was seen. The new bone was deposited predominantly on its surface. In cases with Cerasorb the new bone formation was observed within the porous granules, too. From the obtained results it can be concluded, that the main osteogenetic mechanism in the examined augmentation materials was osteoconduction. The biocompatibility of the used augmentation materials was evidenced by an absence of giant cell granulomatous reaction and of marked inflammatory infiltrate.  相似文献   
997.
PURPOSE: The aim of this study was to evaluate the effects of different inter-implant distances on stress distribution in the bone around the endosseous titanium implants under vertical, oblique and horizontal loads in the posterior mandibular edentulousim by finite element analysis (3D FEA). MATERIALS AND METHODS: 3D FEA models representing mandible and ITI implant (Straumann, Waldenburg, Switzerland) were simulated. The distances in-between the units were set at 0.5, 1.0 and 2.0 cm. Vertical (V) 70 degrees N, 60 degrees oblique (BL) 35 degrees N in buccolingual direction and horizontal (MD) 14 degrees N in mesiodistal direction loads were applied to each of these designs. The principal stresses (tensile and compressive stress) on each model were calculated using MSC MARC finite element analyze solver software. RESULTS: The tensile stress (P(max)) values have been evaluated that they rose at the cervical region of buccal side when the inter-implant distances increased under V and BL loads and they diminished while the inter-implant distances decreased. In short inter-implant distances the compressive stress (P(min)) has been presented with increased values and found at the lingual surface of the cervical region. DISCUSSION: The results of this study indicated that the magnitude of the stress was influenced by complex factors such as the direction of loads and the distance between adjacent fixtures. The stress occurring around fixtures differs significantly with various types of inter-implant distance. CONCLUSION: The evaluation of tensile and compressive stresses for cortical and cancellous bone under V, MD and BL loading conditions in aspect of inter-implant distance shows; the 1.0 cm of inter-implant distance is the optimum distance for two fixture implantation.  相似文献   
998.
The canine parasite Dirofilaria immitis can infect humans. Patients with pulmonary dirofilariosis develop significantly higher thromboxane B2 levels than healthy individuals living in areas where dirofilariosis is endemic and in areas where dirofilariosis is not endemic. The possible role of Wolbachia bacteria in the appearance of this eicosanoid is discussed.  相似文献   
999.
The increased immigration from developing regions to Western countries raises public health concerns related to blood-borne viruses. The prevalence of human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), and human T-lymphotropic virus (HTLV) infections among recent immigrants attending several Spanish diagnostic centers in years 2002 and 2003 was examined. Genetic characterization of viral subtypes and its relationship with distinct at-risk populations was carried out. A total of 1,303 immigrants were identified. They originated in Latin America (46.9%), Sub-Saharan Africa (23.7%), Eastern Europe (9.4%), and the Maghreb (9.2%). Seroprevalence rates were as follows: HIV-1 4.2%, HBV 4.1%, HCV 2.9%, and HTLV-1 0.8%. All patients with HIV-1 non-B subtypes, HBV genotypes E and A3, and HCV genotype 4 were sub-Saharan Africans, and had been infected mainly through heterosexual contacts. In contrast, Latin American homo/bisexual men carried HIV-1 subtype B most likely acquired after their arrival to Spain. In conclusion, while Sub-Saharan Africans carry wide diverse genetic variants of blood-borne viruses, the absence of high-risk practices in most cases could limit the spread of these variants. In contrast, Latin Americans with high-risk sexual practices may be a particularly vulnerable collective to acquire blood-borne viruses in the receptor country.  相似文献   
1000.
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