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71.
This study demonstrated that distinct patterns of active behaviors are produced by antidepressants that selectively inhibit norepinephrine (NE) or serotonin (5-HT) uptake in the rat forced swimming test (FST). A behavior sampling technique was developed to score the active behaviors swimming, climbing and diving, as well as immobility. The rat's behavior was recorded at the end of each 5-s period during the test session. The sampling technique was both reliable, as demonstrated by test-retest reliability and inter-rater reliability, and valid, as shown by comparison to the timing of behavior durations. Five different antidepressant drugs which block monoamine uptake and two 5-HT1A receptor agonists were shown to decrease immobility in the FST; however, they produced distinct patterns of active behaviors. The selective NE uptake inhibitors desipramine and maprotiline selectively increased climbing, whereas the selective serotonin reuptake inhibitors (SSRIs) fluoxetine, sertraline and paroxetine selectively increased swimming. The 5-HT1A receptor agonists 8-OH-DPAT and gepirone also selectively increased swimming. These results show that:1) SSRIs are not false negatives in the FST; 2) at least two behaviorally distinct processes occur in the FST; and 3) enhancement of NE neurotransmission may mediate climbing in the FST, whereas enhancement of 5-HT neurotransmission may mediate swimming.  相似文献   
72.
Background: As in many parts of the world, the Schirmer tear test is the main test used by optometrists in Saudi Arabia for assessing adequacy of tear production. Variability of the test has been reported in different ethnic groups but not in Arabs. This paper looks at the mean and repeatability of the values obtained by the Schirmer test in a normal Arab population Method: The test was performed on the right eyes of 23 young adult Saudi male subjects at five visits over two weeks. Result: Results showed that for each subject the test values were not repeatable, varying widely over the period of evaluation. The mean value was estimated at 10.6 mm and the 95 per cent confidence limits were 7.9 and 13.3 mm. It was also established that the greater the amount of tears, the greater the variability. Conclusion: This study supports the claim that the Schirmer test is not repeatable and hence is unreliable. Therefore, caution should be exercised in employing it for clinical diagnosis. (Clin Exp Optom 1995; 78: 5: 190–193)  相似文献   
73.
正常人口腔粘膜不同部位表面感觉的测试   总被引:1,自引:0,他引:1  
目的 建立正常人口腔粘膜不同部位表面感觉的正常参考值,并测试各年龄组感觉值是否存在差异。方法 利用动静两点辨别觉试验,测试90例健康人口腔粘膜不同部位的表面感觉。结果 舌尖感觉功能最好,其次为舌背、舌腹、颊粘膜、口底和硬腭。健康人的口腔粘膜不同部位的表面感觉随着年龄增长有显著性变化。结论 口腔粘膜不同部位感觉辨别力存在差异,健康人口底、舌腹、舌背、颊和硬腭粘膜感觉功能有增龄性变化。  相似文献   
74.
Quantitative receptor autoradiography was used to study possible alterations of the densities of multiple serotonin (5-HT) receptor subtypes and of serotonin transporter in the brain of 5-HT(2C) receptor knockout mice. The radioligands employed were [(3)H]citalopram, [(3)H]WAY100,635, [(3)H]8-OH-DPAT, [(3)H]GR125743, [(3)H]sumatriptan, [(3)H]MDL100,907, [(125)I](+/-)DOI, [(3)H]mesulergine, [(3)H]5-HT, [(3)H]GR113808, and [(3)H]5-CT. As expected, radioligands that label 5-HT(2C) receptors showed a complete absence of labeling in mutant mice choroid plexus and significantly reduced densities in other brain regions expressing 5-HT(2C) receptors. With the rest of the radioligands, no significant alterations in the densities of labeled sites were found in any brain region. In situ hybridization showed no changes in 5-HT(2A) receptor and serotonin transporter mRNA levels, whereas 5-HT(2C) receptor mRNA levels were reduced in certain brain regions. The present results indicate that the mouse serotonergic system does not exhibit compensatory up- or down-regulation of the majority of its components (serotonin transporter and most 5-HT receptor subtypes) in response to the absence of 5-HT(2C) receptors.  相似文献   
75.
76.
Ten patients with DSM-III-R obsessive-compulsive disorder (OCD) underwent the desipramine (DMI) growth hormone (GH) stimulation test as well as the dexamethasone suppression test (DST). The results were compared with the responses in a group of matched healthy controls. The GH response to DMI did not differ between patients and controls and 9 of 10 patients showed cortisol suppression in response to dexamethasone. The data suggest that neither alpha 2 adrenergic dysfunction nor DST non-suppression are features of primary OCD.  相似文献   
77.
Abstract: Lobular carcinoma in situ (LCIS) has gone from a rare form of mammary cancer to a marker of increased risk. Treatment options have undergone a corresponding change from ipsilateral mastectomy with axillary node dissection to observation once it became clear that the majority of patients did not progress to invasive cancer. However, recent events suggest a re-evaluation of LCIS management options. It is clear that even meticulous observation may fail to detect invasive cancer before systemic spread has taken place. This fact plus the identification of breast cancer genes have brought a renewed interest in prophylactic mastectomy. At the same time pathologists feel that it is possible to identify microscopic features of LCIS pointing to an increased likelihood of developing invasive cancer. As a result physicians are being asked to better quantitate risks for individual patients. Most patients with LCIS do not need bilateral mastectomies, but we are coming closer to identifying the minority that would be better served by prophylactic surgery.  相似文献   
78.
Zusammenfassung Grundlagen: Der Zweck war es, die Anzahl der im Mammogramm entdeckten duktalen Carcinoma in situ (DCIS) und multizentrische Karzinome aufzudecken. Die verschiedenen Methoden der Biopsie werden diskutiert. Methodik: Rastermammographie (Fokus 0,3 mm) und hochaufl?sende Sonographie (7,5 bis 10 MHz) wurden bei Brustkrebspatientinnen eingesetzt. Ergebnisse: Der Zeitraum der aufgelisteten Patientinnen erstreckt sich über 20 Jahre. Die Zahl der DCIS hat in den letzten Jahren zugenommen und betr?gt nun 18%. Die Mammographie ist hoch sensitiv für Entdeckung von Mikrokalzifikationen. Die Spezifit?t ist gering. Schlu?folgerungen: Die Anzahl der entdeckten DCIS ist in den letzten Jahren besonders angestiegen und wird auch noch weiter bei Verbesserung der mammographischen Techniken ansteigen. Diese Studie wurde vom Ludwig-Boltzmann-Institut für radiologisch-physikalische Tumordiagnostik unterstützt.  相似文献   
79.
As an octanoic acid 13CO2 breath test is frequently used to test gastric emptying of solid food, the purpose of the present study was to study whether oxidative breakdown of octanoic acid is affected by severe liver disease. The design of our study was twofold. First, cirrhotic patients (n = 82) of varying severity were compared with healthy controls (n = 17). Values of half-time, time point of maximal expiration and cumulative recovery of octanoic acid breath tests (OBT) were not significantly different between them. Secondly, cirrhotic patients (n = 10) were studied before placement of transjugular intrahepatic portosystemic shunt, 4-7 days later and 1-2 months later. Values of half-time, time point of maximal expiration and cumulative recovery of consecutive OBTs did not change significantly. The OBT may therefore be a suitable test in the future to detect delayed gastric emptying of solids in cirrhotic patients with reduced liver function and portal hypertension.  相似文献   
80.
The in-vitro oestradiol (E2) and progesterone (P) production by corpora lutea (CL) obtained at sterilization from 30 untreated women and 43 women treated with norethisterone (NET) 300 micrograms daily was measured. The CL were obtained at different stages of the luteal phase in the untreated women [luteinizing hormone (LH) 0 to +3, n = 7; LH +4 to +7, n = 7; LH +8 to +11, n = 9; LH +12 to menses, n = 7] and on days LH +8 to +11 or cycle days 22 to 26 in the NET-treated women. In the treated women, four types of ovarian reaction were identified. Four women showed ovarian reaction Type A (completely inhibited ovarian activity), 14 women Type B (marked follicular activity, but no luteal function), 12 women Type C (normal follicular activity, followed by insufficient luteal function) and 13 women Type D (apparently normal follicular and luteal activity). The CL were incubated in Eagle's medium with and without stimulation by human chorionic gonadotrophin (HCG) for 2 and 4 h. In the untreated women, P and E2 production increased significantly with both incubation time and stimulation by HCG throughout the luteal phase, except in the late luteal phase (LH +12 to menses) where P increased (P less than 0.01) only after 4 h stimulation by HCG. The maximal production of P was found after 4 h incubation with HCG stimulation of CL tissue in the early-mid luteal phase (LH +4 to +7).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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