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101.
A procedure was developed to conduct simultaneously immunocytochemical and neurochemical studies on the serotonergic system in adjacent 300-micron-thick slices of rat hippocampus. This procedure was applied to correlate morphological (innervation pattern and density), neurochemical (5-hydroxytryptamine and 5-hydroxyindolacetic acid levels and [3H]5-hydroxytryptamine uptake and release) and behavioral (spatial learning) effects of neurotoxin-induced denervation and reinnervation by grafting fetal mesencephalic raphe cells. Intracerebroventricular injections of a low dose of 5,7-dihydroxytryptamine caused a discrete serotonergic denervation of the hippocampus. Eleven months after lesioning, 5-hydroxytryptamine and 5-hydroxyindolacetic acid levels and [3H]5-hydroxytryptamine uptake capacity were decreased by 50-60%. By this time, the residual fibers displayed an enhanced vulnerability towards K(+)-induced depolarization. Grafting of a fetal raphe cell suspension resulted in a reinnervation of the host hippocampus. The pattern of reinnervation was comparable to control innervation and the density was supranormal at the level of the graft. As observed semiquantitatively, the innervation density decreased with distance from the core of the graft. Neurochemical studies showed that the fibers were capable of synthesizing, metabolizing and releasing 5-hydroxytryptamine. The turnover of 5-hydroxytryptamine in both the denervated and the reinnervated hippocampus was comparable to that in control tissue. Previous behavioral testing of the denervated and of the denervated and implanted animals did not reveal any effect on spatial learning, either in an individual or in a social test paradigm. The latter data substantiate the notion that interference with the hippocampal serotonergic innervation does not hamper adequate spatial learning.  相似文献   
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104.
Hand-assisted laparoscopic splenectomy for hydatid cyst   总被引:1,自引:1,他引:0  
Splenic hydatidosis is a rare condition. We performed a hand-assisted laparoscopic splenectomy for a large hydatid cyst localized in the center of the spleen. We discuss the advantages of the ``helping hand.' Received: 27 September 1996/Accepted: 19 November 1996  相似文献   
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106.
The Kasabach-Merritt syndrome is characterized by thrombocytopenia and localized coagulopathy associated with a hemangioma. Most techniques applied to eradicate the tumor or accelerate its involution (surgery, radiation therapy, embolization) are invasive and require transfusion of large amounts of blood products. In some cases, medical treatment is the only alternative. Efficacy of steroids and antifibronolytic agents has already been described, but even this approach is associated with the administration of blood products. We report two cases of infants with Kasabach-Merritt syndrome associated with cardiac and hepatic hemangiomas. At admission, both had signs of cardiac failure. They were successfully treated with prednisone and epsilon-aminocaproic acid (EACA). Blood products were not required once the diagnosis was made. These observations have important implications for the management of patients with Kasabach-Merritt syndrome because they show that even in severe cases blood transfusions can be avoided by the use of prednisone and EACA.  相似文献   
107.
The effects of human recombinant plasminogen activator inhibitor (rPAI-1) on thrombolysis with recombinant tissue-type plasminogen activator (rt-PA) were studied in a rabbit model of jugular vein thrombosis. Two functionally distinct rPAI-1 preparations were used in these experiments, including latent rPAI-1 (approximately 2 units of t-PA neutralizing activity per micrograms protein) and reactivated rPAI-1 (approximately 150 units/micrograms). Simultaneous intravenous infusion over 4 h of 1.7 mg/kg of reactivated rPAI-1 (inhibitory capacity approximately 0.5 mg/kg rt-PA) with 0.5 mg/kg of rt-PA completely prevented lysis of a jugular venous thrombus, whereas an equivalent amount of latent PAI-1 did not significantly influence clot lysis. These findings demonstrate that reactivated human rPAI-1 efficiently neutralizes thrombolysis with rt-PA in vivo. Since previous studies have suggested that elevated endogenous levels of PAI-1 do not attenuate the thrombolytic potency of rt-PA in the endotoxin-treated model, we compared the stability of complexes formed by 125I-rt-PA with reactivated human rPAI-1 and with rabbit PAI-1 in vitro. Our findings indicate that both forms of PAI-1 form SDS-stable complexes following incubation with 125I-rt-PA. Thus, it seems likely that elevated levels of active PAI-1 can negate the thrombolytic effects of rt-PA in vivo and argues against the possibility that t-PA can dissociate from PAI-1 and have its activity restored in the presence of a thrombus.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
108.
S9788 is a new triazineaminopiperidine derivate capable of reversing multidrug resistance (MDR) in cells resistant to chemotherapeutic agents such as doxorubicin. It does not belong to a known class of MDR revertants, but its action involves the binding of P-glycoprotein. Thirty-eight evaluable patients with advanced colorectal or renal cell cancer were treated with doxorubicin alone (16 patients) followed after disease progression with combination treatment of doxorubicin plus S9788 (12 patients) or upfront with the combination of doxorubicin plus S9788 (22 patients). S9788 was given i.v. as a loading dose of 56 mg m-2 over 30 min followed by doxorubicin given at 50 mg m-2 as a bolus infusion. Thereafter, a 2-h infusion of S9788 was administered at escalating doses ranging from 24 to 120 mg m-2 in subsequent cohorts of 4-10 patients. Pharmacokinetic analysis demonstrated that concentrations of S9788 that are known to reverse MDR in vitro were achieved in patients at non-toxic doses. Compared with treatment with doxorubicin alone, treatment with the combination of doxorubicin and S9788 produced a significant increase in the occurrence of WHO grade 3-4 granulocytopenia. Treatment with S9788 was cardiotoxic as it caused a dose-dependent and reversible increase in corrected QT intervals as well as clinically non-significant arrhythmias on 24- or 48-h Holter recordings. Although clinically relevant cardiac toxicities did not occur, the study was terminated as higher doses of S9788 may increase the risk of severe cardiac arrhythmias. Twenty-nine patients treated with S9788 plus doxorubicin were evaluable for response, and one patient, who progressed after treatment with doxorubicin alone, achieved a partial response. We conclude that S9788 administered at the doses and schedule used in this study results in relevant plasma concentrations in humans and can safely be administered in combination with doxorubicin.  相似文献   
109.
The aim of this study was to determine whether urge incontinence was associated with a higher prevalence of psychological symptoms than other types of incontinence. The psychological aspects of 110 women presenting with urinary incontinence in general practice were assessed by means of standardised questionnaires and medical history-taking. The results showed no difference in psychological characteristics between patients with urge incontinence and those with other types of incontinence. These findings were contrary to the conclusions of almost all other studies based on populations selected for specialist care. It was concluded that in general practice the psychological approach to urinary incontinence depends more on the individual needs of the patient than specifically on the type of incontinence.  相似文献   
110.
In this text we briefly want to discuss the role of the arthrographic examination of the temporomandibular joint for detection of disc pathology. We will mention the normal anatomy and function of the temporomandibular joint, the technique for performing arthrograms and the classification of the most frequent disc pathology. This will be illustrated by some arthrographic examples of anterior disc displacement without reduction, disc perforation, and medial disc displacement. Finally the advantages of arthrography in comparison with other investigation techniques will be discussed.  相似文献   
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