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11.
Recently, tuberculosis re-emerged as a serious public health problem, in industrialized countries, while remaining it remains a major cause of mortality and morbidity in third world countries. Intraocular localization is rare. The most common manifestation of ocular tuberculosis in patients with miliary is Bouchut tubercules. An atypical feature of ocular tuberculosis is discussed: a pseudotumoral choroid granuloma. The behavior of the lesion and its response to antituberculous therapy was documented clinically by fundus photography on fluorescein angiography.  相似文献   
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Abstract: Increased expression of P‐glycoprotein encoded by the mdr‐1 gene is a well‐characterised mechanism for resistance to cancer chemotherapeutic drugs in cell lines. However, the P‐glycoprotein expression after removal of the selection pressure has not fully been elucidated. The stability of P‐glycoprotein expression in the presence (+) and absence (?) of vincristine (30 or 150 nM) was studied in multidrug resistant K562 cell lines (VCR30+, VCR150+, VCR30? and VCR150?) for 11 months. The P‐glycoprotein protein and mdr‐1 mRNA levels were determined at regular intervals using flow cytometry and real‐time PCR, respectively. Chemosensitivity to a panel of antineoplastic drugs was measured using an MTT assay. The presence of vincristine (VCR30+ and VCR150+) resulted in high and stable levels of P‐glycoprotein and mdr‐1 mRNA during the whole period compared to wild type. As for the VCR30? and VCR150? subcultures, the expressions of P‐glycoprotein and mdr‐1 mRNA were stable for five months, and then the levels decreased rapidly. Concomitantly, the sensitivity to drugs known as P‐glycoprotein substrates was restored. In conclusion, resistant cells growing in the presence of the inducing drug have a stable P‐glycoprotein expression and resistance level, but removing the inducing drug may result in a sudden and rapid lowering of P‐glycoprotein and mdr‐1 mRNA levels as long as five months after drug withdrawal.  相似文献   
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Nasopharyngeal adenoid cystic carcinoma is a rare tumor, few cases have been reported in the literature. The aim of this report is to present a new case of an adenoid cystic carcinoma of the nasopharynx. We report the case of a 50 years-old woman presenting with an adenoid cystic carcinoma of the nasopharynx with diffuse pulmonary metastasis. The treatment combined chemotherapy, based on cisplatin and adriamycin drugs, and palliative radiation therapy at the dose of 30 Gy. The patient died 6 months after diagnosis establishment. The best treatment of adenoid cystic carcinoma is complete surgical resection but extended resection can be difficult in some locations as nasopharynx. The adjuvant radiation therapy seems to improve local control.  相似文献   
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Angiocentric lymphoma of the face is a rare malignancy. During 11 years, only two patients were treated for a lymphoma of the face. The first patient, 31-year-old, had an angiocentric lymphoma of the nasal cavity, the second patient, 40-year-old, had an angiocentric lymphoma of the nasopharynx and the maxillary sinuses, with an extension the hard palate. According to the Ann Arbor classification, the disease was stage IEab and stage IIEbb, respectively. The first patient was treated by chemotherapy alone (COP regimen) and the second patient underwent combined chemotherapy (CHOP) and radiotherapy. The follow-up was marked by progression of the disease 7 and 9 months after the end of the treatment in the two cases. For the angiocentric lymphoma, treatment based on radiotherapy or chemotherapy alone or combined does not often provide local control and the overall survival rate does not exceed 40% at 5 years.  相似文献   
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In order to find new antibacterial agents effective against Staphylococcus aureus, ethanolic extracts of 10 plants were tested. S. aureus (489 samples) were isolated either from healthy carriers (nose and throat) or clinical samples. Out of 489 isolates tested, 98.6% were sensitive to trimethoprim-sulfamethoxazole which was used as the reference antibiotic. From the plant extracts screened for antibacterial activity, Myrtus communis L. (leaves) had the greatest activity, inhibiting the growth of 99% of the isolates. Glycyrrhiza glabra L., Eucalyptus globolus Labill and Menta viridis L., were also active against the isolates inhibiting the growth of 90, 59.5 and 48.7% of the isolates, respectively. All of these extracts were active against the reference strains of S. aureus tested. Saturia hortensis L., Teucrium polium L., and Achillea santolina L., had very little antibacterial activity, while Trigonella foenum graecum L., Echium amoenum Fisch & Mey (flowers) and Juglans regia L. (leaves), had no antibacterial activity against the bacterial isolates.  相似文献   
16.
A peripherally inserted central catheter (PICC) is a thin catheter that is inserted via arm veins and threaded near the heart, providing intravenous access. The final catheter tip position is always confirmed on a chest radiograph (CXR) immediately after insertion since malpositioned PICCs can cause potentially life-threatening complications. Although radiologists interpret PICC tip location with high accuracy, delays in interpretation can be significant. In this study, we proposed a fully-automated, deep-learning system with a cascading segmentation AI system containing two fully convolutional neural networks for detecting a PICC line and its tip location. A preprocessing module performed image quality and dimension normalization, and a post-processing module found the PICC tip accurately by pruning false positives. Our best model, trained on 400 training cases and selectively tuned on 50 validation cases, obtained absolute distances from ground truth with a mean of 3.10 mm, a standard deviation of 2.03 mm, and a root mean squares error (RMSE) of 3.71 mm on 150 held-out test cases. This system could help speed confirmation of PICC position and further be generalized to include other types of vascular access and therapeutic support devices.  相似文献   
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Upshaw–Schulman syndrome (USS) is due to severe congenital deficiency of von Willebrand factor (VWF)‐cleaving protease ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type 1 domains, nr 13) activity resulting in the presence of unusually large forms of VWF in the circulation, causing intravascular platelet clumping and thrombotic microangiopathy. Our patient, a 26‐year‐old man, had attacks of thrombotic thrombocytopenic purpura (TTP) with thrombocytopenia and a urine dipstick positive for hemoglobin (4+), often as the only sign of hemolytic activity. He had ADAMTS13 activity of <1% of normal plasma without the presence of inhibitors of ADAMTS13. ADAMTS13 deficiency was caused by two new mutations of the ADAMTS13 gene: a deletion of a single nucleotide in exon17 (c. 2042 delA) leading to a frameshift (K681C fs X16), and a missense mutation in exon 25 (c.3368G>A) leading to p.R1123H. This case report confirms the importance of the analysis of the ADAMTS13 activity and its inhibitor in patients who have episodes of TTP, with a very low platelet count and sometimes without the classic biochemical signs of hemolysis.  相似文献   
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