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Nutcracker syndrome is caused by compression of the left renal vein between the aorta and the superior mesenteric artery where it passes in the fork formed at the bifurcation of these arteries. The phenomenon results in left renal venous hypertension. The syndrome is manifested by left flank and abdominal pain, with or without unilateral haematuria. The nutcracker syndrome has been treated in various ways. We report one case of the syndrome and discuss the place of surveillance in its management.  相似文献   
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For chronic thromboembolic pulmonary hypertension not amenable to pulmonary endarterectomy, effective medical therapy is desired. In an open-label uncontrolled clinical trial, 104 patients (mean +/- sem age 62 +/- 11 yrs) with inoperable chronic thromboembolic pulmonary hypertension were treated with 50 mg sildenafil t.i.d. At baseline, patients had severe pulmonary hypertension (pulmonary vascular resistance 863 +/- 38 dyn.s.cm(-5)) and a 6-min walking distance of 310 +/- 11 m. Eight patients were in World Health Organization functional class II, 76 in class III and 20 in class IV. After 3 months' treatment, there was significant haemodynamic improvement, with reduction of pulmonary vascular resistance to 759 +/- 62 dyn.s.cm(-5). The 6-min walking distance increased significantly to 361 +/- 15 m after 3 months' treatment, and to 366 +/- 18 m after 12 months' treatment. A subset of 67 patients received a single dose of 50 mg sildenafil during initial right heart catheterisation. The acute haemodynamic effect of this was not predictive of long-term outcome. In this large series of patients with inoperable chronic thromboembolic pulmonary hypertension, open-label treatment with sildenafil led to significant long-term functional improvement. The acute effect of sildenafil may not predict the long-term outcome of therapy.  相似文献   
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The disector, an unbiased stereological method for evaluation of synaptic densities, was used to analyse putative GABA and glutamate innervations of the supraoptic nucleus of virgin and lactating rats. The analysis was performed on ultrathin sections labelled for either of the amino acids with a postembedding immunogold technique. Our observations showed that the volume of the nucleus increased by 40% in lactating animals, an increase due to a significant enlargment of dendritic and somatic, but not vascular, volumes. Nevertheless, values of overall synaptic densities in the whole nucleus remained as high as those in virgin rats (37–40×106 synapses/mm3). About 45% of all synapses were immunoreactive for GABA and 25% for glutamate; there were twice as many GABA- and glutamate-positive synapses on dendrites as on somata. When we estimated synaptic densities in relation to the neuropil (by subtracting the proportion of sampled areas occupied by somatic profiles), we found a significant increase in synaptic density in lactating animals. This affected axodendritic as well as axosomatic synapses, immunopositive and immunonegative for GABA or glutamate. The disector also allowed us to determine that the number of synapses from terminals making contacts on several somata and/or dendrites simultaneously constituted about 9% of all synapses in virgin rats, a proportion which more than doubled in lactating rats. About 50% were immunopositive for GABA and 30% for glutamate.

Our data offer further evidence of physiologically-linked structural synaptic plasticity in the supraoptic nucleus and clearly demonstrate that it affects both inhibitory and excitatory inputs on dendrites, as well as on somata, throughout the nucleus.  相似文献   

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We introduce a new epithelial ovarian carcinoma cell line (UCI 107) from a patient with papillary adenocarcinoma of the ovary who had not been previously treated. The growth characteristics, chemosensitivity, tumorgenicity, cytogenetics, antigen expression, and receptor status were examined. A standardized photometric assay was implemented to determine the response to single drug agents including doxorubicin (ADR), cisplatin (CDDP), and Taxol. Tumorgenicity was determined utilizing female athymic mice implanted either subcutaneously (sc) or intraperitoneally (ip) with 1 × 107 UCI 107 cells. UCI 107 cells grow rapidly in culture with lag phase of approximately 48 hr, population doubling time of 24-36 hr, and saturation density of 4.8 × 105 cells/cm2. The 50% inhibitory concentration values for the chemotherapeutic agents were 0.170, 0.029, and 0.330 μM for ADR, Taxol, and CDDP, respectively. Nude mice produced ip tumors within 15 days, resulting in death from carcinomatosis 40-45 days postimplantation. Subcutaneous tumor nodules (100 mm3 were observed in nude mice 12-13 days post-tumor implantation reaching a maximum tumor volume of approximately 10,000 mm3 by Day 30. The cytogenetic composite karyotype is as follows: 46, X, der (X) t (X;7) (p11;q22), inv dup (1) (q12;q32), t (6;6;11;22) (p21.3;q16;q23.3;q13.3), del (13) (q14.1). The cell line expresses progesterone receptor, increased levels of p53 protein, and cytokeratins. It does not appear to express Her-2/neu protein, estrogen receptor, nor the CA 125 tumor marker. In conclusion, UCI 107 displays unique cellular properties which make it an attractive model for the study of ovarian cancer.  相似文献   
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