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81.
Retroperitoneal space is an exceptional location of extrauterine pregnancy (four cases have been previously reported). The authors report a case of retroperitoneal ectopic pregnancy. Pathogenesis is discussed.  相似文献   
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The functional projection of the medial perforant path (MPP) to different CA3 subfields was studied in urethan-anesthetized rats using current source density analysis. MPP stimulation resulted in an early-latency (presumed monosynaptic) sink with onset of 2-3 ms at the distal apical dendritic layer of CA3 (stratum lacunosum molecule) and a long-latency (presumed disynaptic, >7 ms) sink at stratum lucidum and radiatum of CA3. The population spike (onset 5. 3-6.1 ms), a sink at CA3 pyramidal cell layer, was observed 67% of the time (12 of 18 rats) in CA3a, 44% (8 of 18) in CA3b and 58% (7 of 12 rats) in CA3c following MPP stimulation. Population spike was not observed during presumed disynaptic excitation of CA3. Both early-latency sink (excitatory postsynaptic potential) and population spike in CA3 revealed robust paired-pulse facilitation (PPF). In contrast, little PPF was found for the MPP-evoked excitatory sink at the middle molecular layer of the dentate gyrus. The data suggested that the entorhinal cortex provides a strong monosynaptic excitation of different subfields of CA3. A direct entorhinal to CA3 input bypasses the dentate gyrus and may play a role in normal hippocampal signal processing and neural plasticity.  相似文献   
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The rat recombinant P2X4 purinoceptor was expressed in CHO-K1 cells, and binding studies were performed using the radioligand [35S]adenosine-5'-O-(3-thio)triphosphate ([35S]ATPgammaS). In 50 mM Tris/1 mM EDTA assay buffer, pH 7.4 at 4 degrees, [35S]ATPgammaS bound with high affinity to the P2X4 purinoceptor (KD = 0.13 nM, Bmax = 151 pmol/mg of protein). The purinoceptor agonists ATP and 2-methylthioadenosine triphosphate possessed nanomolar affinity for the P2X4 purinoceptor, whereas the antagonist suramin possessed much lower affinity (IC50 = 0.5 mM). Cibacron blue was more potent than suramin but produced a biphasic competition curve, whereas d-tubocurarine potentiated binding at concentrations in excess of 10 microM. The complex effects of cibacron blue and d-tubocurarine seemed to be due to an allosteric interaction with the P2X4 purinoceptor because these compounds affected radioligand dissociation, measured after isotopic dilution with unlabeled ATPgammaS. Cibacron blue (1-100 microM) and d-tubocurarine (0.1-1 mM) produced rapid (10 sec to 5 min) decreases or increases, respectively, in the level of [35S]ATPgammaS binding measured immediately after initiation of the dissociation reaction. However, the subsequent rates of radioligand dissociation were not markedly different from those measured in their absence. Monovalent cations produced similar affects on the P2X4 purinoceptor and, like d-tubocurarine, increased [35S]ATPgammaS binding. The actions of d-tubocurarine and sodium were not additive. The findings from this study indicate that [35S]ATPgammaS can be used to label the P2X4 purinoceptor and suggest that this binding can be enhanced by monovalent cations and d-tubocurarine and may be subject to negative allosteric modulation to varying degrees by different purinoceptor antagonists.  相似文献   
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13 patients aged 39 to 60 years with coronary atherosclerosis confirmed at selective coronary angiography combined with primary hyperlipidemia (phenotypes 2a and 2b) received enduracin in a dose 1500 mg/day. As a result of the treatment total cholesterol (TC) and LDL cholesterol lowered by 10.3 and 13.1%, respectively, whereas HDL cholesterol rose by 15.2%. Half of the patients demonstrated activation of hepatic transaminases, but discontinuation of the drug was not necessary. In 3 out of 4 patients after 2 years of enduracin treatment stabilization of atherosclerosis was observed. Thus, long-term enduracin is able to inhibit progression of atherosclerosis in coronary heart disease patients.  相似文献   
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BACKGROUND: Supraclinoid carotid aneurysms have traditionally been classified according to their relation to the major carotid branches, but considerable variation exists with respect to site of origin, projection, and relationship to the skull base. Distal internal carotid aneurysms with a superior or medial projection are uncommon vascular lesions, with an unusually high incidence of operative complications. METHODS: Surgical experience with five patients suffering from subarachnoid hemorrhage due to ruptured aneurysms of the dorsomedial wall of the distal internal carotid artery is presented, with emphasis on their angiographic appearance, anatomical features, and operative management. RESULTS: All five patients underwent surgical clipping. Intra-operative rupture occurred in two cases, with avulsion of the aneurysm from the internal carotid artery in both. A third patient experienced recurrent subarachnoid hemorrhage three days after uneventful surgery, due to the clip shearing off of the parent vessel. CONCLUSIONS: Distal internal carotid aneurysms do not conform to the usual principles of aneurysm formation and are unique in their dorsomedial location unrelated to an arterial bifurcation. Although their anatomy is straightforward and exposure is not restricted by bone or dural structures of the skull base, they possess extremely fragile necks which make surgical management particularly hazardous.  相似文献   
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