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A case of Plasmodium falciparum malaria is reported in a 25-year-old pregnant woman with a history of three previous cesarean sections. She developed premature precipitate labor which was complicated by stillbirth, uterine rupture, bladder and vaginal tears necessitating hysterectomy.  相似文献   
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Medullary control of the pontine swallowing neurones in sheep   总被引:3,自引:0,他引:3  
Summary The origin of the inputs from the medullary swallowing centre (dorsal region including the nucleus of the solitary tract, or ventral region corresponding to the reticular formation surrounding the nucleus ambigous) to the pontine swallowing neurones (PSNs) was studied in sheep anaesthetized with halothane.Out of 101 PSNs located in the posterior part of the trigeminal (Vth) motor nucleus, 46 were activated by stimulating either the dorsal (21 neurones) or the ventral (25 neurones) region of the ipsilateral medullary swallowing centre, 3–4 mm rostral from the obex. Thirty-one neurones out of the 46 were identified as a motoneurones supplying swallowing muscles (mylohyoïd, anterior body of digastric and medial pterygoïd). Their average activation latency through stimulation of the dorsal medullary region was about 1 ms longer than through stimulation of the ventral region (3.63 ms±0.81 versus 2.72 ms±0.32).To determine the origin of the medullary input to the PSNs, we tried to activate the medullary swallowing neurones (MSNs) antidromically through stimulating the posterior part of the Vth motor nucleus, which contains the swallowing motoneurones. Seventy-three MSNs were tested (25 located in the dorsal and 48 in the ventral region). None of the dorsal neurones tested could be antidromically activated by pontine stimulation: 15 ventral neurones showed a clear antidromic response (collision test) with an average latency of 2.5 ms±0.73. These neurones, which send their axons into the pons, were all located in the reticular formation, above the nucleus ambiguus, 3–4 mm rostral from the obex.These results suggest that MSNs in the ventral reticular formation connect the medullary swallowing centre to the Vth motor nucleus. They also suggest that during swallowing, inputs originating from the dorsal region of the medullary centre (interneurones programming the motor sequence) are relayed in the ventral region (reticular formation adjacent to the nucleus ambiguus) before reaching the PSNs.This work was supported, in part, by grants from CNRS (LA 205), INRA and M.R.I. (82 E 0685)  相似文献   
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OBJECTIVES: Among 82 patients hospitalized for infective endocarditis between June 1995 and June 2001 at the cardiology B unit of the Rabat University Hospital Morocco, 18 (22%) had one or more vascular complications. We present here a retrospective analysis. PATIENTS AND METHODS: The cohort included 12 men and 6 women, mean age 22 years. Infective endocarditis had grafted on a pre-existing cardiopathy among 17 patients: rheumatic heart disease (n=14), mechanical prosthetic valve (n=2), congenital heart disease (n=1). RESULTS: For 12 patients, vascular disease was the only complication, 1 had two complications and 4 three complications. This gave 26 lesions: 11 neurological complications, 10 arterial diseases involving the limbs including 5 mycotic aneurysms, 2 acute myocardial infarcts, 2 splenic infarcts, and 1 recurrent septic pulmonary embolism. Vascular disease was the inaugural manifestation in 9 patients and 54% of the complications occurred before the end of the second week of antibiotic treatment. Blood cultures were positive in 7 patients (40%). Oral streptococcus was isolated in 5 cases, Gram-negative bacillus in 1 case and Staphylococcus aureus in 1. Echography revealed valvular vegetations in the 16 cases of infective endocarditis on native valves: mitral (n=9), aortic (n=5), mitroaortic (n=1), tricuspid (n=1). Short term outcome was marked by 4 deaths including 3 directly related to the vascular complication. DISCUSSION: We emphasize the variable and diverse features of vascular complications of infective endocarditis. Prevention and early diagnosis are essential to institute optimal management of infective endocarditis.  相似文献   
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Conventional polyurethane foam has non-tunable sound absorption properties. Here, a magneto-induced foam, called magnetorheological (MR) foam, was fabricated with the feature of being able to tune sound absorption properties, primarily from the middle- to higher-frequency ranges. Three different samples of MR foams were fabricated in situ by varying the concentration of Carbonyl Iron Particles (CIPs) (0, 35, and 75 wt.%). The magnetization properties and tunable sound absorption characteristics were evaluated. From the magnetic saturation properties, the results showed very narrow and small coercivity of hysteresis loops relative to the soft magnetic properties of the CIPs. MR foam with 75 wt.% CIPs showed a higher magnetic saturation at 91.350 emu/g compared to MR foam with 35 wt.% CIPs at 63.896 emu/g. For tunable sound absorption testing, the effect of ‘shifting’ to higher frequency was also observed when the magnetic field was applied, which was ~10 Hz for MR foam with 35 wt.% CIPs and ~130 Hz for MR foam with 75 wt.% CIPs. As the latest evolution of semi-active noise control materials, the results from this study are valuable guidance for the advancement of MR-based devices.  相似文献   
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The ob17 cell line is a clonal line established from epididymal fat pads of C57 BL/6J ob/ob mice. After conversion into adipose-like cells, ob17 presents both the morphological and biochemical properties of mature rodent fat cells. The adipose conversion process is best represented by a stochastic model in which a pool of stem cells (adipoblasts) gives rise to clusters of adipose cells and to additional stem cells that remain in the population. The role of the different factors involved in the adipose conversion process of ob17 cells is discussed, i.e. 1) mitogenic factors, that enhance the number of committed cells (ACF or adipose conversion factor(s)) 2) lipogenic factors, that enhance the expression of adipocyte enzyme markers (insulin) and 3) adipogenic factors, that are obligatory requirements for adipose conversion (triiodothyronine, growth hormone and other pituitary factors).  相似文献   
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