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排序方式: 共有900条查询结果,搜索用时 15 毫秒
1.
Mt D. Dbrssy Chockalingam Ramanathan Danesh Ashouri Vajari Yixin Tong Thomas Schlaepfer Volker A. Coenen 《The European journal of neuroscience》2021,53(1):89-113
Deep brain stimulation (DBS) in psychiatric illnesses has been clinically tested over the past 20 years. The clinical application of DBS to the superolateral branch of the medial forebrain bundle in treatment‐resistant depressed patients—one of several targets under investigation—has shown to be promising in a number of uncontrolled open label trials. However, there are remain numerous questions that need to be investigated to understand and optimize the clinical use of DBS in depression, including, for example, the relationship between the symptoms, the biological substrates/projections and the stimulation itself. In the context of precision and customized medicine, the current paper focuses on clinical and experimental research of medial forebrain bundle DBS in depression or in animal models of depression, demonstrating how clinical and scientific progress can work in tandem to test the therapeutic value and investigate the mechanisms of this experimental treatment. As one of the hypotheses is that depression engenders changes in the reward and motivational networks, the review looks at how stimulation of the medial forebrain bundle impacts the dopaminergic system. 相似文献
2.
Sonographic evaluation of gallbladder kinetics: in vitro and in vivo comparison of different methods to assess gallbladder emptying. 总被引:3,自引:0,他引:3
Bernd Wedmann Gabriele Schmidt Martin Wegener Christoph Coenen Dieter Ricken Cornelia Drge 《Journal of clinical ultrasound : JCU》1991,19(6):341-349
In an in vitro study, 10 gallbladders of adult pigs and 6 gallbladders of lambs, all removed immediately after slaughtering, were stimulated in a water bath by electric means to induce active contraction. Gallbladder emptying was followed by ultrasonography employing five measurement procedures: (1) gallbladder width, (2) longitudinal planimetry, (3) transverse planimetry, (4) ellipsoid method, and (5) sum of cylinders method. In an in vivo investigation, gallbladder emptying of 30 volunteers (12 healthy subjects, 18 diabetics) was evaluated in the same way after ingestion of a fatty meal. Gallbladder width was found to be unsuitable to estimate the decrease in gallbladder volume due to a nonlinear relation of the parameters. Longitudinal planimetry tended to be less valid than transverse planimetry in assessing gallbladder volume reduction. The most valid estimation of gallbladder volume decreases was obtained by the two three-dimensional procedures. However, in neither in vitro nor in vivo could a significant difference between the sum of cylinders method and the ellipsoid method in determining relative volume reduction be established. We conclude that a three-dimensional measurement procedure should be used for valid assessments of gallbladder motility. However, according to our data there is no advantage in using the time-consuming sum of cylinders method compared to the simple ellipsoid method. 相似文献
3.
The effects on seizures, EEG and behavior of the non-NMDA receptor antagonist CNQX (6-cyano-7-nitroquinoxaline-2,3-dione), were studied in the WAG/Rij rat with absence epilepsy. Intracerebroventricular injections (10, 50, and 100 nmol/5 microliters CNQX) showed that CNQX decreases the number of spike wave discharges in a dose-dependent way. Coinjection of CNQX (100 nmol/5 microliters) and AMPA (0.1 pmol/5 microliters), kainic acid (0.01 nmol/5 microliters) or NMDA (50 pmol/5 microliters) attenuated the CNQX response, indicating that CNQX acts on both non-NMDA and NMDA receptors. The observed effects appear to be specific manipulations of the epilepsy not mediated by behavioral changes. 相似文献
4.
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
5.
6.
S. Spellerberg P. Reimer G. Blessing H.H. Coenen S.M. Qaim 《Applied radiation and isotopes》1998,49(12):611
55Co and 57Co were produced via (p, α) and (p, 2p) reactions, respectively, on highly enriched 58Ni. Thin deposits of 58Ni on Cu backing, obtained electrolytically, were irradiated using a slanting beam. The separation of radiocobalt and the recovery of the enriched target material were effected via anion-exchange chromatography. 相似文献
7.
Excitation functions of the reactions (nat)Sb((3)He,xn)(124,123,121)I were measured from their respective thresholds up to 35 MeV, with particular emphasis on data for the production of the medically important radionuclide (124)I. The conventional stacked-foil technique was used. From the experimental data the theoretical yields of the three investigated radionuclides were calculated. The yield of (124)I over the energy range E9(30He) = 35 --> 13 MeV amounts to 0.95 MBq/microA h. The radionuclidic impurities are discussed. A comparison of (3)He- and alpha-particle-induced reactions on antimony for production of (124)I is given. The alpha-particle-induced reaction on enriched (121)Sb and the (3)He-particle-induced reaction on enriched (123)Sb would lead to comparable (124)I yields, but the level of impurities in the latter case would be somewhat higher. 相似文献
8.
S A Kandil I Spahn B Scholten Z A Saleh S M M Saad H H Coenen S M Qaim 《Applied radiation and isotopes》2007,65(5):561-568
Excitation functions were measured by the stacked-foil technique for (nat)Rb(alpha,xn)(87m,87m+g,88)Y and (nat)Sr(alpha,xn)(86,88,89)Zr reactions from their respective thresholds up to 26 MeV. The samples for irradiation were prepared by sedimentation and pellet pressing techniques. The measured data were compared with those available in the literature. From the excitation functions, integral yields of the products were calculated. The suitable energy ranges for the production of (87)Y and (88)Y via (nat)Rb(alpha,xn) processes and of (89)Zr via the (nat)Sr(alpha,xn) process are E(alpha)=26-->20 MeV, E(alpha)=26-->5 MeV and E(alpha)=20-->8.5 MeV, respectively. The respective yields amount to 8.2, 0.08 and 0.9 MBq/microA h. Production of (88)Y is feasible if a waiting time of about 2 months is allowed to let the impurities decay out. Also, (87)Y can be produced with a relatively low impurity of (88)Y. The yields of both (88)Y and (87)Y via the present routes are, however, appreciably lower than those via the (nat)Sr(p,xn) processes. There is a possibility to produce (89)Zr via the alpha-particle irradiation of (nat)Sr. The yield is rather low but would be considerably increased if enriched (86)Sr would be used as target material. The radionuclidic impurity levels in all the three products are discussed. 相似文献
9.
Anita E. Kelly Matthew E. Coenen Benjamin L. Johnston 《Journal of traumatic stress》1995,8(1):161-169
One hundred six undergraduate (83 women and 23 men) completed surveys concerning their most traumatic life event, the feedback they received following their disclosure of the event to others, and how they felt after the disclosure. Results indicated that the better they felt after disclosure, the less disturbed they were by thoughts of the event at the time of the study. In addition, the more personal the trauma was, the worse they felt after their disclosure, and the more disturbed they were about the trauma. However, no significant relation existed between the positivity (e.g., supportiveness) of their confidant's feedback and their present degree of disturbance. Implications for understanding the complex relation between confiding traumatic events and resolving feelings surrounding those events were discussed. 相似文献
10.
Decreased prefrontal 5-HT2A receptor binding in subjects at enhanced risk for schizophrenia 总被引:4,自引:0,他引:4
Hurlemann R Boy C Meyer PT Scherk H Wagner M Herzog H Coenen HH Vogeley K Falkai P Zilles K Maier W Bauer A 《Anatomy and embryology》2005,210(5-6):519-523
The brain serotonin-2A receptor (5-HT2AR) has been implicated in both the pathology of schizophrenia and the therapeutic action of atypical antipsychotics. However,
little is known about the 5-HT2AR status before the onset of schizophrenia and before the exposure to antipsychotics. We used [18F] altanserin and positron emission tomography (PET) in a pilot study of 6 individuals suspected to be at elevated risk for
schizophrenia and seven age-matched controls to test the hypothesis that regional 5-HT2AR binding is altered in the prodromal stages of schizophrenia. Distribution volume ratios (DVRs) as a proxy for 5-HT2AR availability were significantly reduced in prefrontal cortex regions of at-risk subjects, implicating early abnormalities
of serotonergic neurotransmission that antecede the onset of schizophrenia. 相似文献