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91.
Bruce J. Rousaville Myrna M. Weissman Patricia H. Rosenberger Charles H. Wilber Herbert D. Kleber 《Journal of affective disorders》1979,1(4):255-267
Previous investigators have reported a high prevalence of depressive symptoms in drug-dependent patients. Given the responsiveness of depressive disorders to both psychological and pharmacological treatments, it is desirable to find an economical, efficient screening instrument to detect depressive disorders in this population. In this study, 6 depression symptom screening scales (Beck Depression Inventory, Hamilton Depression Scale, Raskin Depression Scale, Degree of Illness Rating, Symptom Checklist 90 Overall, and Depression Subscale) based on either clinician interview or patient self report, were compared according to their utility in detecting cases of depression among 64 applicants for treatment at a substance abuse treatment unit of a community mental health center. The criteria for a case of depression were the Research Diagnostic Criteria (RDC) which are specified and operationalized. Cases identified using previously described cutoff scores on the screening scales were compared to rates based on the RDC and sensitivity and specificity were determined. The results showed that: (1) although the sensitivity of the symptom scales was applicable, ranging from 65--94%, the specificity was less impressive, ranging from 39--61%, and (2) the Beck Depression Inventory, a 13-item patient self report was the most sensitive and specific and is recommended for screening drug-dependent populations for depression. 相似文献
92.
Effect of stretch on calcium channel currents recorded from the antral circular myocytes of guinea-pig stomach 总被引:7,自引:0,他引:7
Wen Xie Xu Sung Joon Kim Sang Jeong Kim Insuk So Tong Mook Kang Jong Chul Rhee Ki Whan Kim 《Pflügers Archiv : European journal of physiology》1996,432(2):159-164
The effect of membrane stretch on voltage-activated Ba2+ current (I
Ba) was studied in antral circular myocytes of guinea-pig using the whole- cell patch-clamp technique. The changes in cell volume
were elicited by superfusing the myocytes with anisosmotic solutions. Hyposmotic superfusate (202 mosmol/l) induced cell swelling
and increased peak values of I
Ba at 0 mV (from −406.6 ± 45.5 pA to −547.5 ± 65.6 pA, mean ± SEM, n = 8) and hyperosmotic superfusate (350 mosmol/l) induced cell shrinkage and decreased peak values of I
Ba at 0 mV (to −269.5 ± 39.1 pA, n = 8). Such changes were reversible and the extent of change was dependent on the osmolarity of superfusate. The values of
normalized I
Ba at 0 mV were 1.43 ± 0.04, 1.30 ± 0.06, 1.23 ± 0.04, 1.19 ± 0.04, 1 and 0.68 ± 0.06 at 202, 220, 245, 267, 290 and 350 mosmol/l,
respectively (n = 8). I
Ba was almost completely blocked by nicardipine (5 μM) under hyposmotic conditions. The values of steady-state half-inactivation
voltage (−37.7 ± 3.3 and −36.5 ± 2.6 mV, under control and hyposmotic conditions, respectively) or the half-activation voltage
(−13.6 ± 2.3 and −13.9 ± 1.9 mV) of I
Ba were not significantly changed (P > 0.05, n = 6). Cell membrane capacitance was slightly increased from 50.00 ± 2.86 pF to 50.22 ± 2.82 pF by a hyposmotic superfusate
(P < 0.05, n = 6). It is suggested that cell swelling increases voltage-operated L-type calcium channel current and that such a property
is related to the response of gastric smooth muscle to mechanical stimuli.
Received: 14 November 1995/Received after revision and accepted: 8 January 1996 相似文献
93.
The site and concentration dependence of the blocking effect of Ba2+ onNecturus gallbladder epithelium has been investigated. A new approach was used which combines time-dependent electrical cell coupling
analysis with intermittently performed measurements of transepithelial and apparent intracellular impedance. From the coupling
pulse data the sum of apical and basolateral membrane conductances is obtained, which is then held constant during fitting
of the impedance data. This combination technique yields more reliable estimates of apical and basolateral membranes resistances
(R
a,R
bl) and of tight junction resistance (R
j) than our previous impedance analysis technique. Using the new approach we have found that luminal Ba2+ concentrations between 0.5 and 1.0 mmol/l increaseR
a with saturation-type kinetics without affectingR
bl andR
j, while higher luminal Ba2+ concentrations progressively increaseR
j. Corresponding effects were observed under serosal Ba2+. The results validate the new impedance analysis approach and demonstrate that millimolar concentrations of Ba2+ block tight junction conductances. Accordingly, Ba2+ can no longer be considered a tool to exclusively alter cell membrane resistances in epithelia. 相似文献
94.
Mihaela Humar M. Kordaš Živa Melik 《Pflügers Archiv : European journal of physiology》1980,386(1):67-70
Papaine is known to detach cholinesterases from the synaptic cleft. It could be expected that this would result in an increase of the amplitude and half-time of the end-plate current. Thus, the effect of papaine on the end-plate current should be similar to the effect of anticholinesterase methanesulfonyl-fluoride.The end-plate current was recorded in frog skeletal muscle at various levels of membrane potential, before and after papaine was added to the bath.The effect of papaine was an increase of the half-time of the end-plate current, similarly as after treatment of the muscle by methanesulfonylfluoride.It seems that both papaine and methanesulfonyl-fluoride have a similar mechanism of action. In either experimental condition hydrolysis of transmitter is decreased or abolished, which results in an increase of the half-time of the end-plate current.This work was supported by the Research Community of Slovenia 相似文献
95.
肉苁蓉(Cistanche deserticola Y.C.Ma)为国家二级保护植物,具有极好的药用价值。为保护肉苁蓉资源,充分发挥其经济价值,本文总结了肉苁蓉资源分布、生物学特性、炮制方法、化学成分、药理作用、组织培养以及栽培技术等研究概况,并分析了研究中存在的问题,提出了今后肉苁蓉开发利用的研究方向。 相似文献
96.
本文从还原剂SnCl3用量,反应体系pH值,McAb使用浓度等方面研究了^55mTc直接法标记单克隆抗体的最佳条件,并探讨了VitC对标记反应的影响。β-ME法的单抗,三氯乙酸沉淀法测定标记率,上行纸层析法测定标记产物胶体含量。结果表明,^90mTc直接标记中还原剂SnCl2浓度以0.01-0.04mg/ml为宜,反应最适pH值在5.6-6.8,McAb最低使用浓度应为500μh/ml以上,适量V 相似文献
97.
Adrià Rofes Emmanuel Mandonnet Vânia de Aguiar Brenda Rapp Kyrana Tsapkini Gabriele Miceli 《Cognitive neuropsychology》2019,36(3-4):117-139
ABSTRACTElectrical Stimulation (ES) is a neurostimulation technique that is used to localize language functions in the brain of people with intractable epilepsy and/or brain tumors. We reviewed 25 ES articles published between 1984 and 2018 and interpreted them from a cognitive neuropsychological perspective. Our aim was to highlight ES as a tool to further our understanding of cognitive models of language. We focused on associations and dissociations between cognitive functions within the framework of two non-neuroanatomically specified models of language. Also, we discussed parallels between the ES and the stroke literatures and showed how ES data can help us to generate hypotheses regarding how language is processed. A good understanding of cognitive models of language is essential to motivate task selection and to tailor surgical procedures, for example, by avoiding testing the same cognitive functions and understanding which functions may be more or less relevant to be tested during surgery. 相似文献
98.
F. C. Howarth Allan J. Levi Jules C. Hancox 《Pflügers Archiv : European journal of physiology》1996,431(5):713-722
The delayed rectifier potassium current (I
K) is known to be important in action potential repolarisation and may contribute to the diastolic pacemaker depolarisation
in pacemaker cells from the heart. In this study, using whole-cell patch clamp, we investigated the characteristics of I
K in morphologically normal cells from the atrioventricular node (AVN) and ventricle of the rabbit heart. Cells were held at
−40 mV and 5 μM external nifedipine was used to block L-type calcium current (I
Ca,L). Significant I
K was observed with pulses to potentials more positive than −30 mV. The steady-state activation curve in both cell types showed
maximal activation at between + 10 and + 20 mV. Half-maximal activation of I
K occurred at −4.9 and −4.1 mV with slope factors of 8.3 and 12.4 mV in ventricular and AVN cells, respectively. Using pulses
of increasing duration, significant I
K tails after repolarisation from + 40 mV were observed with pulses of 20 ms and increased with pulses up to 100–120 ms in
both cell types. Pulses of longer duration did not activate further I
K and this suggested that only the rapid component of I
K, called I
Kr, was present in either cell type. Moreover, I
K tails after pulses to all potentials were blocked completely by E-4031, a selective blocker of I
Kr. The reversal potential of I
K varied with the concentration of external K. Superfusion of AVN cells with medium containing 4, 15 and 40 mM [K+]o resulted in reversal potentials of −81, −56 and −32 mV, respectively, which are close to values predicted if the I
K channel were highly selective for K. The time constants for deactivation of I
K in ventricle and AVN on return to −40 mV after a 500-ms activating pulse to + 60 mV were 480 ms and 230 ms, respectively.
The faster deactivation of I
K in AVN cells was a distinguishing feature and suggests that there may be differences in the I
Kr channel protein between ventricular and AVN cells.
Received: 24 July 1995 /Received after revision: 20 October 1995 /Accepted: 23 October 1995 相似文献
99.
Kandori A Hosono T Chiba Y Shinto M Miyashita S Murakami M Miyashita T Ogata K Tsukada K 《Medical & biological engineering & computing》2003,41(1):33-39
The paper presents an evaluation of the possibility of using fetal magnetocardiogram (FMCG) signals to estimate and classify
the accessory pathway in fetal Wolff-Parkinson-White (WPW) syndrome. The FMCG signals of two fetuses with WPW syndrome (type
A) were detected using a 64-channel superconducting quantum-interference device system. An average across the cycles of these
signals was taken to obtain clear WPW signals. To determine the direction and position of the accessory pathway in a fetal
heart accurately, the accessory pathway and activated pathway at the peak of the QRS complex thus obtained were estimated
for each fetus, using a single-dipole model. The phase angle (about 90o) between the equivalent current dipoles (ECDs) was the same for both fetuses. This angle suggested that the accessory pathway
is in the left side of the heart, i.e. that the pathway exists in the position of the accessory pathway in a fetus with WPW
syndrome from the angle between the ECD of the accessory pathway and the ECD of the peak in the QRS complex was thus demonstrated. 相似文献
100.
Tanaka Y Kato K Notohara K Nakatani Y Miyake T Ijiri R Nishimata S Ishida Y Kigasawa H Ohama Y Tsukayama C Kobayashi Y Horie H 《The Journal of pathology》2003,199(2):185-190
This study concerns the significance of aberrant (nuclear/cytoplasmic) expression of beta-catenin in pancreatoblastoma (PBL). On immunohistochemistry, all seven PBLs examined showed nuclear/cytoplasmic expression of beta-catenin, predominantly in the squamoid corpuscles (SCs). In areas with acinar/ductular differentiation, few tumour cells displayed nuclear/cytoplasmic expression of beta-catenin and more than half of the tumour cells showed membranous expression. Two out of five (40%) tumours examined showed missense mutations in codons 33 and 37 of exon 3 of the beta-catenin gene. No mutation of the adenomatous polyposis coli (APC) gene was detected in two of the remaining three tumours. Amplifiable DNA for APC analysis was not obtained from the one other tumour. Immunoreactivity for cyclin D1, one of the nuclear targets of beta-catenin, was found predominantly in the SCs of the seven tumours. In contrast, the Ki-67 labelling index was 2-4% (median 3%) in the SCs and 8-18% (median 12%) in the other areas, indicating a negative correlation with nuclear cyclin D1 reactivity. These results imply that in PBLs, nuclear/cytoplasmic accumulation of beta-catenin and overexpression of its target gene cyclin D1 are not associated with the induction of tumour cell proliferation. Nuclear/cytoplasmic accumulation of beta-catenin may be related to the morphogenesis of the SCs that are considered most characteristic for PBL. 相似文献