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121.
OBJECTIVE: To discuss the occurrence of genital chlamydia in developed countries and review the literature assessing the potential risk factors for this sexually transmitted disease. DATA SOURCES: A MEDLINE search was performed for all English citations from 1985 to 2000 that contain the keywords "Chlamydia trachomatis", "chlamydial infections", "risk factors" and "sex behaviour". All relevant references cited in articles that were obtained from the search were also included. DATA EXTRACTION: ALL ARTICLES OBTAINED FROM THE ABOVE SOURCES WERE EXAMINED, AND WERE INCLUDED IN THE REVIEW IF THEY MET THE FOLLOWING CRITERIA: primary study examining sociodemographic or behavioural risk factors associated with genital chlamydial infection using multivariate analysis; study subjects 12 years of age and older; and study setting in a developed country. DATA SYNTHESIS AND CONCLUSIONS: Genital chlamydial infection has become the most commonly reported bacterial infection in North America over the past decade. Thirty-eight cross-sectional studies and six cohort studies were included in the present review. Most studies demonstrated that young men and women are at higher risk of being infected with chlamydia than older subjects. Chlamydia seems to be found in a diverse group of people, and unlike gonorrhea, is not concentrated in low income, minority core groups with high rates of partner change. However, a number of studies have shown that communities with well-established control programs are beginning to demonstrate this pattern. There is no clear evidence that chlamydia is associated with type of partners, contraceptive use, or age at first intercourse. Future research should follow this sexually transmitted disease as it evolves through the epidemiological stages to ensure that preventive and treatment services are reaching those people who are most likely to be infected.  相似文献   
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Complications following supracondylar fracture of humerus are well-known. Pre- and post-operative complications have been documented in the literature. Neurovascular injury due to fracture fragments following this type of fracture is described. Iatrogenic brachial artery during surgical treatment of this fracture is unknown to the literature. So we report a rare case of iatrogenic brachial artery injury during pinning of supracondylar fracture of humerus and try to create awareness to the surgeons that such injuries can occur with improper operative techniques.  相似文献   
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Vaginal cancer is rare worldwide and represents 2% of all gynaecological cancers in Singapore. Primary vaginal malignancies are rare and vaginal metastases constitute the majority of vaginal malignancies. Most of these metastases arise from the cervix, endometrium or ovary, although they can also metastasise from distant sites such as the colon, breast and pancreas. We report a rare case of vaginal metastasis in a patient with previous gastric and rectal adenocarcinomas. An 89-year-old woman with a history of gastric and rectal malignancy presented with postmenopausal bleeding. A 2-cm vaginal tumour at the introitus was discovered upon examination. This case demonstrates the importance of performing a gynaecological examination during follow-up for patients with a history of malignancy. The prognosis for vaginal metastasis is poor, as it is often associated with disseminated disease. Depending on the extent of the lesions, radiotherapy or surgery can be considered.  相似文献   
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In tetralogy of Fallot septal defect is usually large because of malalignment of outlet septum, restrictive defect has been reported rarely. We present a case of tetralogy of Fallot with accessory tricuspid leaflet tissue restricting ventricular septal defect. The report includes echocardiographic and catheter images of this rare presentation of tetralogy of Fallot.  相似文献   
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Scrub typhus and leptospirosis are both zoonosis and systemic febrile illnesses with diverse clinical manifestations and they may present with similar signs and symptoms. We present a case of co-infection of scrub typhus and leptospirosis from Himachal Pradesh in the Himalayan region of India.  相似文献   
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C1q modulates the differentiation and function of cells committed to the monocyte-derived dendritic cell (DC) lineage. Because the 2 C1q receptors found on the DC surface-gC1qR and cC1qR-lack a direct conduit into intracellular elements, we postulated that the receptors must form complexes with transmembrane partners. In the present study, we show that DC-SIGN, a C-type lectin expressed on DCs, binds directly to C1q, as assessed by ELISA, flow cytometry, and immunoprecipitation experiments. Surface plasmon resonance analysis revealed that the interaction was specific, and both intact C1q and the globular portion of C1q bound to DC-SIGN. Whereas IgG reduced this binding significantly, the Arg residues (162-163) of the C1q-A chain, which are thought to contribute to the C1q-IgG interaction, were not required for C1q binding to DC-SIGN. Binding was reduced significantly in the absence of Ca(2+) and by preincubation of DC-SIGN with mannan, suggesting that C1q binds to DC-SIGN at its principal Ca(2+)-binding pocket, which has increased affinity for mannose residues. Antigen-capture ELISA and immunofluorescence microscopy revealed that C1q and gC1qR associate with DC-SIGN on blood DC precursors and immature DCs. The results of the present study suggest that C1q/gC1qR may regulate DC differentiation and function through the DC-SIGN-mediated induction of cell-signaling pathways.  相似文献   
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