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471.
We report on a series of 146 cases of vaginal delivery after previous Caesarean section conducted between 1993 and 2002 at the University Teaching Hospital, Yaounde (Cameroon). During the period under review 945 cases of Caesarean section were done out of a total of 9 439 deliveries (10 %). Delivery was spontaneous in 141 cases whereas in 5 cases it was assisted by vacuum extraction. In 13 cases Caesarean section was carried out after failure of trial of labour. Maternal mortality, resulting from pulmonary embolism, was observed in 1 case. We conclude that strict selection of patients who had previous Caesarean section for trial of labour renders vaginal delivery a safe alternative to Caesarean section.  相似文献   
472.
Background  Transcatheter arterial chemoembolization (TACE) has been limited in palliative treatment of unresectable hepatocellular carcinoma (HCC) with major portal vein (PV) invasion due to the possibility of liver failure following embolization. Transcatheter arterial chemoinfusion (TACI) has been an option in such cases.
Aim  To compare clinical outcomes after TACE vs. TACI in HCC patients with major PV occlusion.
Methods  We compared clinical outcomes after TACE vs. TACI in HCC patients with major PV occlusion. From 2005 to 2007, 110 HCC patients with major PV thrombosis were treated with TACE ( n  = 49) or TACI ( n  = 61).
Results  The morbidity rate was similar for both TACE (6.1%) and TACI (6.5%) patients, and complications were adequately managed using medical treatment. The Kaplan–Meier survival analysis showed that the survival period was significantly longer for the TACE group (median: 14.9 months) than for the TACI (median: 4.4 months) group ( P  < 0.001). There was a higher probability of death in the TACI group than in the TACE group in both our multivariate Cox-proportional hazards (OR 3.09, P  < 0.001) and the propensity score-matched (27 pairs) cohort analyses (OR 2.27, P  = 0.024).
Conclusions  Transcatheter arterial chemoembolization can be safely performed in HCC patients with main PV occlusion. Compared with TACI, TACE may result in longer survival of HCC patients with major PV occlusion.  相似文献   
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474.
The Na(+)/I(-) symporter (NIS) is a key plasma membrane protein that mediates active I(-) uptake in the thyroid, lactating breast, and other tissues with an electrogenic stoichiometry of 2 Na(+) per I(-). In the thyroid, NIS-mediated I(-) uptake is the first step in the biosynthesis of the iodine-containing thyroid hormones, which are essential early in life for proper CNS development. In the lactating breast, NIS mediates the translocation of I(-) to the milk, thus supplying this essential anion to the nursing newborn. Perchlorate (ClO(4)(-)) is a well known competitive inhibitor of NIS. Exposure to food and water contaminated with ClO(4)(-) is common in the U.S. population, and the public health impact of such exposure is currently being debated. To date, it is still uncertain whether ClO(4)(-) is a NIS blocker or a transported substrate of NIS. Here we show in vitro and in vivo that NIS actively transports ClO(4)(-), including ClO(4)(-) translocation to the milk. A simple mathematical fluxes model accurately predicts the effect of ClO(4)(-) transport on the rate and extent of I(-) accumulation. Strikingly, the Na(+)/ ClO(4)(-) transport stoichiometry is electroneutral, uncovering that NIS translocates different substrates with different stoichiometries. That NIS actively concentrates ClO(4)(-) in maternal milk suggests that exposure of newborns to high levels of ClO(4)(-) may pose a greater health risk than previously acknowledged because ClO(4)(-) would thus directly inhibit the newborns' thyroidal I(-) uptake.  相似文献   
475.
476.
 

Aims:


Intravascular lymphomatosis is an uncommon type of non-Hodgkin's lymphoma characterized by intravascular proliferation of neoplastic lymphoid cells. Although the tumour is basically a systemic disease, eventually involving multiple organs, primary presentation in the lung is rare.  

Methods and results:


We describe the clinicopathological features of two patients with intravascular lymphomatosis presenting in the lung. One patient complained of fever, headache and chest pain; the other, of dyspnoea on exertion and headache. Both patients showed reticulonodular density on chest radiography and decreased diffusion capacity. Lung biopsy showed features characteristic of intravascular lymphomatosis. Malignant lymphoid cells were CD30 positive T-cells of anaplastic large cell type in one patient and B-cells of large cell type in the other. There was a poor response to chemotherapy and both patients died of the disease within 3 months of diagnosis.  

Conclusions:


These cases and 10 previous reports illustrate the need to include intravascular lymphomatosis in the differential diagnosis of interstitial lung disease.  相似文献   
477.
Fractional flow reserve (FFR) is an index for identifying functionally significant stenotic lesions. A FFR value of ≤0.75 is considered clinically significant and indicative of physiological ischemia. Focal lesions with 30–80 % stenosis by angiography with lesion lengths of less than 20 mm were selected from left anterior descending arteries of 74 patients. The analysis for the total lesion was processed first, and then each lesion was divided into three segments to assess the each segment. Data on plaque geometry and composition of two FFR groups, FFR ≤ 0.75 and FFR > 0.75, were compared by total and segmental analysis. Lesions with FFR ≤ 0.75 had more fibrofatty tissue (13.5 ± 7.4 vs. 10.2 ± 6.5 %, p = 0.05) and less dense calcium (7.2 ± 5.3 vs. 11.9 ± 7.5 %, p = 0.01) compared to lesions with FFR > 0.75. The content of necrotic core in mid segments was higher compared to proximal and distal segments (22.9 ± 10.6, 20.2 ± 10.9, 17.1 ± 11.2 %, respectively, p = 0.032) in lesions with FFR > 0.75 but the difference was less obvious in lesions with FFR ≤ 0.75 (17.9 ± 9.9, 18.7 ± 9.9, 15.8 ± 9.0 %, respectively, p = 0.533). Coronary lesions with FFR > 0.75 have larger content of dense calcium and slightly less fibrofatty tissue compared to lesions with FFR ≤ 0.75. While segmental plaque compositions for each segment show noticeable variations in lesions with FFR > 0.75 such as high concentrations of necrotic core in mid segment, these differences in each segment become obscure in FFR ≤ 0.75 and are evenly distributed across the lesion.  相似文献   
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