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1.
Chronic expanding intracerebral hematoma   总被引:21,自引:0,他引:21  
The cases of 10 normotensive patients with chronic intracerebral hematomas are reported. The patients' median age at diagnosis was 42 years. The median duration of symptoms was 22 days. Seizures were the presenting symptom in 50% of the cases. Computerized tomography almost consistently demonstrated ring-shaped lesions with mass effect and perifocal edema. Arteriography revealed that all but one of the lesions were avascular. All patients had superficial white matter lesions, mostly in the frontoparietal region. All patients were treated surgically. Most of the hematomas were encapsulated and contained blood in various stages of organization. The thick capsule consisted of an outer layer of collagenous tissue and an inner layer of granulation tissue. Occult cerebrovascular malformations were detected in two instances. There were two deaths, both related to recurrent postoperative hemorrhage. This entity can present much like a brain malignancy and should be considered in the differential diagnosis of ring-shaped lesions whatever the clinical presentation. Strategies of treatment are discussed.  相似文献   
2.
Neuroimaging in Pineal Tumors   总被引:4,自引:0,他引:4  
F Reis  MD  AV Faria  MD  PhD  VA Zanardi  MD  PhD  JR Menezes  MD  F Cendes  MD  PhD  LS Queiroz  MD  PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread.  相似文献   
3.
4.
Myo-inositol transport in the central nervous system   总被引:18,自引:0,他引:18  
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5.
In the tail suspension test (an animal model of depression) the duration of immobility during the 6 min of observation was 56.84 +/- 6.54 sec in sham-ovariectomized mice and 113.11 +/- 7.86 sec 30-32 days after ovariectomy. Estradiol (10, 100 or 1,000 micrograms/kg) and progesterone (50, 1,000 or 10,000 micrograms/kg), subcutaneously injected daily 4 times before the test, restored the duration of immobility in ovariectomized mice to normal, while having no effect on sham-operated animals. On the other hand, desipramine (20 mg/kg IP 1 hr before testing) significantly reduced the duration of immobility both in ovariectomized and in sham-operated mice. These data indicate that ovarian sex hormones, while having no "antidepressant," desipramine-like, effect on the behavior of intact adult female mice, have such an effect in ovariectomized mice, and enable the animal to cope in a "normal" way with adverse environmental situations.  相似文献   
6.
It has been shown that long-term administration ofl-sulpiride induces a down-regulation of receptor-associated adenylate cyclase activity in the frontal cortex of rats, an adaptive response that is typically associated with the chronic administration of antidepressants. Here we show that in two animal models of depression-like behavior (forced swim in rats and tail suspension in mice), the long-term (21 days) administration ofl-sulpiride at a non-neuroleptic dose (2 mg/kg IP twice a day) significantly decreases the duration of immobility, the effect being similar to that of desipramine (20 mg/kg IP). The same dose (2 mg/kg) ofl-sulpiride, acutely administered, has no effect at all. On the other hand, either chronic (21 days) or acute administration of neuroleptic doses ofl-sulpiride have an opposite effect, and indeed increase the duration of immobility. These results are an in vivo support to the in vitro findings suggesting that low doses ofl-sulpiride may have antidepressant-like activity.  相似文献   
7.
Antidepressant drugs are effective in anxiety states, including panic disorder. Both clinical and animal studies indicate that l-sulpiride, at low, non-neuroleptic doses, has antidepressant activity. The present study examined the effect of an antidepressant dose of l-sulpiride (4 mg/kg per day SC), compared with a well-established antidepressant drug (fluoxetine, 3 mg/ kg per day SC), in a rat model of anticipatory anxiety/panic behavior: conditioned fear stress-induced freezing behavior. Long-term (26 days) administration of l-sulpiride almost completely abolished freezing, a similar effect being produced by fluoxetine (freezing duration, in seconds: controls, 148.1 ± 29.6; l-sulpiride, 27.5 ± 8.3; fluoxetine, 72.0 ± 15.2). The same doses of l-sulpiride (4 mg/kg SC) and fluoxetine (3 mg/kg SC) had no effect when administered for shorter periods (1, 5, or 12 days). No effect was produced by the long-term (26 days) administration of a neuroleptic dose of l-sulpiride (20 mg/kg per day SC). These results demonstrate that long-term administration of low, non-neuroleptic doses of l-sulpiride, is highly effective in an animal model of anticipatory anxiety/panic behavior. Received: 13 March 1998/Final version: 23 July 1998  相似文献   
8.
Labial adhesions are usually seen in early childhood or in the postmenopausal years, but this clinical entity is rarely seen in the reproductive years. We report a case of labial adhesion with acute urinary retention secondary to Bartholin's abscess in a reproductive‐aged woman with normal menstrual periods. We emphasize the possible occurrence of labial adhesion following Bartholin's abscess in the reproductive years with normal estrogen levels.  相似文献   
9.
Heparin-induced thrombocytopenia is characterized by moderate thrombocytopenia and thrombotic complications, whereas quinine/quinidine-induced thrombocytopenia usually presents with severe thrombocytopenia and bleeding. Using flow cytometry and assays of procoagulant activity, we investigated whether sera from patients with these immune drug reactions could stimulate normal platelets to generate platelet-derived microparticles with procoagulant activity. Sera or purified IgG from patients with heparin-induced thrombocytopenia stimulated the formation of platelet-derived microparticles in a heparin-dependent fashion. Further studies showed that heparin-induced thrombocytopenia sera also produced a marked increase in procoagulant activity. In contrast, sera from patients with quinine- or quinidine-induced thrombocytopenia did not generate platelet-derived microparticles nor generate increased procoagulant activity. However, quinine/quinidine-induced thrombocytopenia sera produced a significant increase in the binding of IgG to platelets in a drug-dependent fashion, whereas sera from patients with heparin-induced thrombocytopenia demonstrated no drug-dependent binding of IgG to platelets. We also observed increased levels of circulating microparticles in patients with acute heparin-induced thrombocytopenia compared with control patients. Our observations indicate that the generation of procoagulant platelet-derived microparticles in vivo is a plausible explanation for the thrombotic complications observed in some patients with heparin-induced thrombocytopenia.  相似文献   
10.
Bone metastases frequently occur in the advanced stages of breast cancer. At this stage, the disease is deemed incurable. To date, the mechanisms of breast cancer‐related metastasis to bone are poorly understood. This may be attributed to the lack of appropriate animal models to investigate the complex cancer cell–bone interactions. In this study, two established tissue‐engineered bone constructs (TEBCs) were applied to a breast cancer‐related metastasis model. A cylindrical medical‐grade polycaprolactone‐tricalcium phosphate scaffold produced by fused deposition modelling (scaffold 1) was compared with a tubular calcium phosphate‐coated polycaprolactone scaffold fabricated by solution electrospinning (scaffold 2) for their potential to generate ectopic humanised bone in NOD/SCID mice. While scaffold 1 was found not suitable to generate a sufficient amount of ectopic bone tissue due to poor ectopic integration, scaffold 2 showed excellent integration into the host tissue, leading to bone formation. To mimic breast cancer cell colonisation to the bone, MDA‐MB‐231, SUM1315, and MDA‐MB‐231BO breast cancer cells were cultured in polyethylene glycol‐based hydrogels and implanted adjacent to the TEBCs. Histological analysis indicated that the breast cancer cells induced an osteoclastic reaction in the TEBCs, demonstrating analogies to breast cancer‐related bone metastasis seen in patients.  相似文献   
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