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EDITORIAL COMMENT: We accepted this case for publication to remind readers that although uterine rupture during labour in a primigravida is extremely uncommon it does occur, or at any rate nulliparas can develop abdominal pain and shock in labour with a haemoperitoneum resulting from a tear in a vein in the lower posterior uterine wall. When one sees the hugely dilated uterine and ovarian venous plexuses at Caesarean section it is easy to believe that bleeding from such a vessel during labour could be prodigious. This case suggests that a dilated vein with blood flow derangements may be the cause. Nonetheless, as the authors warn us, the necessary response is not a precise diagnosis, but rapid laparotomy. See also Editorial Comment to Chin MMS, Harvey JA, Duffy BL. Uterine rupture during labour in a primigravida. Aust NZ J Obstet Gynaecol 1996; 36: 210.  相似文献   
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The effects of 3,4-dihydro-6-[4-(3,4-dimethoxybenzoyl)-1-piperazinyl]-2(1H)-quinolinone (vesnarinone) on the growth of glioma cells were examined in vitro. Vesnarinone at a dose of 100 mug/ml suppressed the growth of four different glioma cell lines, U-251MG, U-373MG, U-87MG and A-172, by approximately 50%, with an elongation of the cytoplasmic process on day 5 of culture. The long-term culture of U-87MG with 10 mug/ml of vesnarinone was continued up to day 34. Although growth suppression was approximately 25% on day 5, it reached over 95% on day 34. An increase in the cyclic adenosine monophosphate content of glioma cells cultured with vesnarinone was observed by enzyme-linked immunosorbent assay (ELISA). The accumulation of glial fibrillary acidic protein was observed to occur with vesnarinone by ELISA. These findings suggest that vesnarinone suppressed the growth and induced differentiation of glioma cells in vitro.  相似文献   
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Recent concern regarding health effects of air pollution in Japan has concentrated mainly on traffic-induced air pollution and its health effects in large cities. In Japan, where many people in large cities have been living near major roadways, the increase of automobile exhaust due to heavy traffic congestion will predictably cause a greater impact on people living near major roadways. We surveyed the characterization of residential suspended particulate matter (SPM) and nitrogen dioxide (NO2) concentrations along the major roadways in Tokyo, along with a health survey on the respiratory conditions of residents living in the same area, to examine the relationships between indoor pollutant levels, prevalence of respiratory symptoms and distance from roadways. The environmental monitoring was conducted in five phases. Using a newly developed SPM sampler and NO2 filter badge, continuous 4 day (96 hours) measurements were conducted in two hundred residential homes for four weeks. NO2 was measured in the living room, kitchen and outside of each home, while SPM was monitored in the living room. Health information was collected in October 1987 using ATS-DLD self-administered questionnaires. Of the 1,093 homes investigated, responses from 805 homes were received. The following results were obtained. SPM and NO2 concentrations showed large variations. Indoor pollution levels mostly depended on indoor sources, i.e. cigarette smoking and unventilated space heaters, and the effects of those indoor sources were influenced by the building structure with respect to air tightness. An association between increase in pollutant levels and the distance from the roadway was observed. However its effect is small compared to indoor source effects. The prevalence rate of respiratory symptoms was higher in those areas nearest roadways with heavy traffic both in children and adults. These results suggest the presence of a relationship between automobile exhaust and health effects.  相似文献   
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Background: The local anesthetic lidocaine affects neuronal excitability in the central nervous system; however, the mechanisms of such action remain unclear. The intracellular sodium concentration ([Na+]i) and sodium currents (INa) are related to membrane potential and excitability. Using an identifiable respiratory pacemaker neuron from Lymnaea stagnalis, the authors sought to determine whether lidocaine changes [Na+]i and membrane potential and whether INa is related to these changes.

Methods: Intracellular recording and sodium imaging were used simultaneously to measure membrane potentials and [Na+]i, respectively. Measurements for [Na+]i were made in normal, high-Na+, and Na+-free salines, with membrane hyperpolarization, and with tetrodotoxin pretreatment trials. Furthermore, changes of INa were measured by whole cell patch clamp configuration.

Results: Lidocaine increased [Na+]i in a dose-dependent manner concurrent with a depolarization of the membrane potential. In the presence of high-Na+ saline, [Na+]i increased and the membrane potential was depolarized; the addition of lidocaine further increased [Na+]i, and the membrane potential was further depolarized. In Na+-free saline or in the presence of tetrodotoxin, lidocaine did not change [Na+]i. Similarly, hyperpolarization of the membrane by current injections also prevented the lidocaine-induced increase of [Na+]i. In the patch clamp configuration, membrane depolarization by lidocaine led to an inward sodium influx. A persistent reduction in membrane potential, resulting from lidocaine, brings the cell within the window current of INa where sodium channel activation occurs.  相似文献   

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BACKGROUND: The development of atherosclerotic cardiovascular complications caused by hyperlipidemia is a common and serious problem for long-term survivors of organ transplantation. However, adhesion molecules such as intercellular adhesion molecule (ICAM)-1 and lymphocyte function-associated antigen (LFA)-1 are involved in allograft rejection, possibly by providing costimulatory signals. 3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor cerivastatin has been shown to suppress ICAM-1 expression in acute inflammatory responses. METHODS: In this study, we evaluated the immunosuppressive effects of cerivastatin in rat cardiac allografts. The hearts of Fischer rats were transplanted heterotopically into Lewis rats. Cerivastatin (2 mg/kg) was administrated intraperitoneally to recipients for 7 consecutive days from the day before transplantation. RESULTS: Graft survival in the cerivastatin-treated group (n = 8) was significantly longer than in controls (n = 10) (24.6 +/- 2.2 days vs 10.2 +/- 1.3 days, p < 0.05). Mixed lymphocyte reaction (MLR) showed that on Day 8 after grafting, the proliferative response of alloreactive T cells against F344 alloantigen in cerivastatin-treated rats was significantly more suppressed than in Lewis rats. The Interleukin-2 concentration of supernatant in MLR cultures in the cerivastatin-treated group was lower than in the control group. Immunohistochemical analysis showed that the percentage of CD4-positive cells to infiltrating mononuclear cells was less prominent in the cerivastatin-treated group (9.8% +/- 2.2%) than in the control group (20.9% +/- 3.2%). CONCLUSIONS: The HMG-CoA reductase inhibitor cerivastatin effectively suppressed acute graft rejection, possibly by blocking intercellular signals via ICAM/LFA-1, and cerivastatin may be a candidate for treating patients with hyperlipidemia who undergo organ transplantation.  相似文献   
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We describe our technique for performing direct thoracoscopic closure of a congenital partial pericardial defect, which was successfully employed in a 15-year-old boy. This is the first such report of a procedure that is noninvasive and may therefore become the treatment of choice for patients with a small congenital pericardial defect.  相似文献   
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