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Background  

Common vaginal infections that manifest in women are usually easily diagnosed. However, Chlamydia infection is often asymptomatic, leading to infertility before it is detected. If it occurs in pregnancy, it could lead to significant neonatal morbidity. It may also play a role with other viral infections for e.g. Human Papilloma Virus in the development of cervical cancer. The objective of this study was to determine the prevalence of Chlamydia infection in women undergoing screening for cervical abnormalities as a part of a research project in primary and secondary care institutions in the United Arab Emirates.  相似文献   
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Background  

Despite more than a decade of extensive, international efforts to characterize and understand the increased symptom and illness-reporting among veterans of the 1991 Gulf War, concern over possible long-term health effects related to this deployment continue. The purpose of this study was to describe the long-term hospitalization experience of the subset of U.S. Gulf War veterans still on active duty between 1994 and 2004.  相似文献   
25.
Ingested sharp foreign bodies usually lodge themselves in the pharynx unlike their more common smooth counterparts, which are found in the upper esophagus. These are very rare in infants and pose problems like delayed presentation and occasionally extraluminal migration. A very rare case of through and through penetration of neck by an ingested nail in an infant, which presented 8 months after its ingestion, is reported.  相似文献   
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PURPOSE: To determine the epidemiological pattern and risk factors involved in suppurative corneal ulceration in Gangetic West Bengal, eastern India, and to identify the specific microbial agents responsible for corneal infections. METHODS: All patients with suspected microbial keratitis presenting to the corneal clinic at Disha Eye Hospital, Barrackpore, West Bengal, India, from January 2001 to December 2003 were evaluated. Sociodemographic data and information pertaining to the risk factors were recorded. After diagnosing infective corneal ulcer clinically, corneal scraping and cultures were performed. RESULTS: Over a three-year period, 1198 patients with suppurative keratitis were evaluated. Ocular trauma was the most common predisposing factor in 994 (82.9%) patients (P< 0.0001), followed by use of topical corticosteroids in 231 (19.28%) patients. Cultures were positive in 811 (67.7%) patients. Among these culture positive cases, 509 (62.7%) patients had pure fungal infections (P< 0.001), 184 (22.7%) patients had pure bacterial infections and 114 (14.1%) had mixed fungal with bacterial infections. Acanthamoeba was detected in 4 (0.49%) patients. The most common fungal pathogen was Aspergillus spp representing 373 (59.8%) of all positive fungal cultures (P< 0.0001), followed by Fusarium spp in 132 (21.2%) instances. Most common bacterial isolate was Staphylococcus aureus, representing 127 (42.6%) of all the bacterial culture (P< 0.0001) followed by Pseudomonas spp 63 (21.1%). CONCLUSION: Suppurative keratitis in Gangetic West Bengal, most often occurs after a superficial corneal trauma with vegetative or organic materials. Fungal ulcers are more common than bacterial ulcers. Aspergillus spp and Staphylococcus aureus were the most common fungus and bacteria respectively. These "regional" findings have important public health implications for the treatment and prevention of suppurative corneal ulceration in this region of India.  相似文献   
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Despite the increasing and successful use of laser in Medicine and Odontology, the possible iatrogenic and otherwise deleterious side effects of this radiation remain mostly unknown. In previous studies, it was shown that both the embryonic and the post-hatched chicken constitute reliable experimental models for this type of studies. Hence, the purpose of the present work was to analyze the structural and cytochemical alterations of the lingual glands of the newborn chicken irradiated with low energy He-Ne laser. This laser produced regressive structural changes of the glands towards the embryonic stage as well as hyperplasia of the reserve glandular basal cells. Furthermore, a decrease in the glycoprotein content and a rise in the sulphated glycosaminoglycans were also found. These results corroborate the pathogenic effects of the He-Ne- laser on the experimental model employed and, at the same time, emphasize the importance of considering, regarding clinical applications, possible previous neoplastic alterations as well as adverse reactions which might appear once laser therapy has been installed.  相似文献   
29.
Using a new stop-flow perfusion technique with microspectrofluorometric determination of luminal fluid pH, we have studied which substrates or incubation conditions allow isolated rabbit proximal tubules to attain in-vivo-like rates of HCO3- absorption (J(HCO3)) and maximal responses of J(HCO3) to norepinephrine (NE). Essentially three incubation media were tested: plasma-like HCO(3-)-Ringer solution containing 5 mmol/l D-glucose (G-Ringer sol.), the same solution also containing 10 mmol/l lactate and 5 mmol/l L-alanine, (LAG-Ringer sol.), and two tissue culture media (DMEM and RPMI 1640). Compared to G-Ringer sol., application of LAG-Ringer sol. in the bath and/or lumen, or application of DMEM or RPMI 1640 in the bath either slightly increased or decreased J(HCO3) with borderline significance. However, RPMI 1640 plus 1 mmol/l pyruvate stimulated J(HCO3) by 55%. While NE (10(-5) mol/l), if applied in G-Ringer sol., had no effect, in the presence of LAG-Ringer sol. it increased J(HCO3) by approximately =40%, and in the presence of DMEM or RPMI 1640 it increased J(HCO3) by approximately =100%. This stimulation by NE followed Michaelis-Menten kinetics with an EC50 value of 0.25 micromol/l and was probably mediated by alpha1-adrenergic receptors. Additional cell pH measurements suggest that NE stimulates the basolateral Na+-HCO3- cotransporter which then becomes susceptible to inhibition by cAMP. We conclude that incubation in tissue culture media allows isolated proximal tubules to maintain a better functional state than the commonly used solutions with unphysiologically high substrate concentrations.  相似文献   
30.
The histogenesis of the salivary glands was structurally and cytochemically studied in human embryos and fetuses during the period of 8 to 32 weeks of intrauterine life. Glandular buds appeared at about 12 weeks of embryonic development. The rounded distal ends of the epithelial cords and neighbouring mesenchyma showed small and abundant PAS positive and alcianophilic granules. At age 14 weeks the secretory end pieces and the duct system were seen at different morphologic and structural stages of a differentiation. Mucous acini with scanty mixed acini predominated and serous acini appeared occasionally. From 20 to 24 weeks the mucous acini stained with toluidine blue featured different degrees of metachromasia even in the case of cells of the same acinus. In the ducts it was also possible to identify metachromatic cells intermingled with basophilic cells in the epithelial coat. These findings suggest that the palatine glands present typical histophysiological material from 14 to 20 weeks. The presence of PAS positive, alcianophilic and metachromatic secretory substance in the acinar lumen and the luminal content of ducts suggests that mucin secretion begins during intrauterine life.  相似文献   
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