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Extrinsic compression of the renal artery due to a fibromuscular band originating from the diaphragm was encountered in a 26-year-old patient who had systemic hypertension associated with stenosis and kinking of one of her renal arteries. After surgical decompression, the renal artery assumed a normal expansion with disappearance of hypertension. Six other cases of extrinsic compression of the renal artery have been found in the literature. Surgical treatment is mandatory in all cases because the mechanism that causes the lesion makes percutaneous transluminal angioplasty illusory.  相似文献   
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Transcutaneous bilirubinometry is an effective screening tool for neonatal jaundice in full-term babies. But its accuracy is not shown yet in preterm infants. METHODOLOGY: We carried out a prospective study in a neonatal intensive care unit. The study included 47 preterm infants. From birth, a transcutaneous bilirubin measurement (BTc) using the BiliCheck was made on the forehead of each newborn every 8 h. Blood sampling for determination of total serum bilirubin (BS) was combined with BTc: 1) if value of BTc was higher than limits values for phototherapy; 2) on the second day of life and 3) 4 hours after cessation of phototherapy. RESULTS: Mean gestational age was 30 week and mean birth weight was 1419 g. We studied 151 pairs of BTc and BS. Mean values obtained by BTc and BS were respectively 160.6+/-50 mumol/L and 190.6+/-61.4 mumol/L. A significant correlation between BTc and BS was found. But the limits of agreement were very wide. The negative predictive value (NPV) of BTc was above 90% in each group of gestational age. DISCUSSION: The need for phototherapy cannot be determined by BTc in preterm infants. But the BTc is reliable when its value is under the limits for phototherapy. CONCLUSION: With a very high incidence of neonatal jaundice (87%) in our cohort, a value of BTc under the limits for phototherapy has a good NPV in preterm infants.  相似文献   
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This study was devoted to tumor differentiation in liver MR T1-weighted imaging with superparamagnetic iron oxide (SPIO). Twenty-one patients with 40 liver lesions were studied at 1.5 T. Before and at least 45 minutes after SPIO administration, turbo-field-echo (TFE) T1-weighted, TFE T1 × T2*-weighted (MXT), and fat-suppressed turbo-spin-echo T2-weighted images were acquired. A quantitative analysis was performed blindly. On TFE T1-weighted images, the signal enhancement was ?33% ± 12 for the liver, ?24% ± 2 for adenomas and focal nodular hyperplasia, +60% ± 33 for the hemangiomas; metastases and cyst enhancement were not significant. After SPIO on TFE T1-weighted images, the hemangioma-to-liver signal ratio (149% ± 18) was definitely higher than the mean metastasis-to-liver signal ratio (90% ± 16). This T1-related differentiation ability lacked dramatically on TFE MXT images and, in one case, was reduced on post-SPIO TFE T1-weighted images by a long imaging delay after SPIO administration (2 hours).  相似文献   
5.
To monitor the presence of genotypic HIV-1 variants circulating in eastern Cameroon, blood samples from 57 HIV-1-infected individuals attending 3 local health centers in the bordering rural villages with Central African Republic (CAR) were collected and analyzed phylogenetically. Out of the 40 HIV-1 strains with positive polymerase chain reaction (PCR) profile for both gag and env-C2V3,12 (30.0%) had discordant subtype or CRF designation: 2 subtype B/A (gag/env), 1 B/CRF01, 2 B/CRF02, 1 CRF01/CRF01.A, 2 CRF11/CRF01, 1 CRF13/A, 1 CRF13/CRF01, 1 CRF13/CRF11, and 1 G/U (unclassified). Twenty-eight strains (70.0%) had concordant subtypes or CRF designation between gag and env: 27 subtype A and 1 F2. Out of the remaining 17HIV-1 strains negative for PCR with the env-C2V3 primers used, 10 (58.8%) had discordant subtype or CRF, and 7 (41.2%) had concordant one based on gag/pol/env-gp41 analysis. Altogether, a high proportion (22/57, 38.6%) of the isolates were found to be recombinant strains. In addition, an emergence of new forms of HIV-1 strains, such as subtype B/A (gag/env), B/CRF01 and B/CRF02, was identified. The epidemiologic pattern of HIV-1 in eastern Cameroon, relatively low and high prevalence of CRF02 and CRF11, respectively, was more closely related to those of CAR and Chad than that of other regions of Cameroon, where CRF02 is the most predominant HIV-1 strain. These findings strongly suggest that this part of Cameroon is a potential hotspot of HIV-1 recombination, with a likelihood of an active generation of new forms of HIV-1 variants, though epidemiologic significance of new HIV-1 forms is unknown.  相似文献   
6.
Partial interruption of inferior vena cava (I.C.V.) forms an integral part of treatment of thromboembolic disease. The most frequently used filter worldwide is currently that of Greenfield, but although its effectiveness and permeability are remarkable it can be the subject of transfixions, sliding movements and migrations. A new model of the authors' own conception is presented which eliminates these faults. The "2612" filter is based on the same concepts, but has added to it 6 lateral flanges soldered to the base of the arms, these applying pressure to the I.V.C. and ensuring its perfect positioning, and 12 hooks (6 turned downwards and 6 upwards) ensuring perfect stability. Results of a multicentre trial in 35 patients, after insertion of the "2612" filter and follow up assessment after 3 months (28 cases) by cavography and in some patients by a scan, showed permeability of 93% and total efficacy. No side effects were reported. This filter appears to represent true progress in the means of interrupting I.V.C., and further studies are contemplated.  相似文献   
7.
Summary Twenty evaluable patients with advanced measurable colorectal cancer received 3-week courses of a combination of IV dacarbazine 300 mg/m2/day from day 1 to day 5 and IV mitomycin 2 mg/m2/day from day 1 to day 5. Fourteen of these patients had had no prior chemotherapy and received two or more courses of this two-drug regimen. None of the patients achieved complete or partial response. Severe to life-threatening myelosuppression, was encountered in patients with prior radiotherapy and or prior chemotherapy, and/or in patients with a Karnofsky score 70. Hematologic toxicity was mild in the other patients. Nonhematologic toxic effects were generally mild to moderate and consisted essentially in nausea and vomiting. It is concluded that in our hands the regimen selected for this trial has no significant antitumor activity in advanced colorectal cancer.  相似文献   
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Evolutionary analyses have revealed an origin of pandemic HIV-1 group M in the Congo River basin in the first part of the XX century, but the patterns of historical viral spread in or around its epicentre remain largely unexplored. Here, we combine epidemiologic and molecular sequence data to investigate the spatiotemporal patterns of the CRF02_AG clade. By explicitly integrating prevalence counts and genetic population size estimates we date the epidemic emergence of CRF02_AG at 1973.1 (1972.1, 1975.3, 95% CI). To infer the phylogeographic signature of this clade at a regional scale, we analyze pol and env time-stamped sequence data from 10 countries using a Bayesian phylogeographic approach based on an asymmetric discretized diffusion model. Our data confirms a spatial origin of CRF02_AG in the Democratic Republic of Congo (DRC) and suggests that viral dissemination to Cameroon occurred at an early stage of the evolutionary history of CRF02_AG. We find considerable support for epidemiological linkage between neighbour countries. Compilation of ethnographic data suggested that well-supported viral migration did not reflect sustained human migratory flows. Finally, using sequence data from 15 locations in Cameroon, we use relaxed random walk models to explore the spatiotemporal dynamics of CRF02_AG at a finer geographical detail. Phylogeographic dispersal in continuous space reveals that at least two distinct CRF02_AG lineages are circulating in overlapping regions that are evolving at different evolutionary and diffusion rates. In conclusion, by combining molecular and epidemiological data, our results provide a time scale for CRF02_AG, early 70s, place its spatial root in the DRC within the putative root of group-M diversity and propose a scenario of chance-exportation events for the spatiotemporal patterns of a successful HIV-1 lineage both at a regional and country-scale.  相似文献   
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