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101.
An experiment with N=40 university students investigated the impact of social observation on cardiovascular reactivity during performance on a computer-based letter detection task. The study was conducted in a 2 (social observation: no vs. yes)x2 (task difficulty: easy vs. difficult) between-persons design. In accordance with engagement-related predictions about the role of social observation in active coping, the mere presence of an experimenter who observed participants during task performance increased the reactivity of systolic blood pressure when the task was difficult, but not when the task was easy. Without social observation, reactivity was modest in both the easy and the difficult conditions. Reactivity of diastolic blood pressure described the same pattern as systolic blood pressure. Results are interpreted as evidence for an effort-related analysis of cardiovascular reactivity based on the principles of motivational intensity theory. 相似文献
102.
G. Aumüller Paul-Martin Holterhus Lutz Konrad Burkhard von Rahden Olaf Hiort Murielle Esquenet Guido Verhoeven 《Anatomy and embryology》1998,197(3):199-208
As it is suggested that the androgen receptor mechanism is required for prostatic development, we attempted to determine
the appearance, expression and distribution of the androgen receptor in embryonic, infantile and pubertal human prostate.
Using mono- and polyclonal antibodies and a digoxigenin-labeled 713 bp riboprobe, the androgen receptor expression in paraffin
sections of fetal, infantile, and pubertal prostates was studied at the protein and RNA level. Under highly standardized conditions,
application of the polyclonal antibodies resulted in a weak cytoplasmic and nuclear labeling of the epithelium of fetal glands.
No immunoreaction was obtained with monoclonal antibodies. Applying the polyclonal antibody to pubertal and adult specimens,
immunoreactivity of the androgen receptor was positive in nuclei of adluminal and basal epithelial cells, in interstitial
and vascular smooth muscle cells and vascular endothelium, whereas ganglionic cells and enteroendocrine cells were negative.
In situ hybridization with the digoxigenin-labeled riboprobe gave clear positive results already in epithelium of very young
fetal specimens. A semiquantitative visual evaluation of in situ hybridizations showed that intermediate intensity of expression
was increased in pubertal and adult specimens, whereas strong expression was reduced in prostatic epithelium. Conclusions:
The essential findings are: (1) an early expression of androgen receptor mRNA in the fetal prostate; (2) no immunoreaction
of monoclonal antibodies against the androgen receptor in the same specimens, (3) a decrease of androgen receptor mRNA expression,
but increase in immunoreactivity of the androgen receptor protein with the onset of glandular maturation during puberty.
Accepted: 29 September 1997 相似文献
103.
Stefano Thellung Alessandra Barzizza Guido Maura Maurizio Raiteri 《Naunyn-Schmiedeberg's archives of pharmacology》1993,348(4):347-351
Summary The glutamatergic mossy fibre granule cell pathway has been investigated in rat cerebellar slices. Exposure to 35 mM KCI, a concentration of K+ known to elicit Ca2+-dependent releases of excitatory amino acids from cerebellar slices, raised cGMP levels. The cGMP response was decreased in a concentration-dependent manner by D-(–)-2-amino-5-phosphonopentanoic acid (D-AP5) and by 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) indicating the involvement of ionotropic glutamate receptors of both the N-methyl-D-aspartate (NMDA) and the non-NMDA type. The K+-evoked production of cGMP was potently inhibited (EC50 = 1.21 nM) by 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI), a selective 5-HT2 receptor agonist. The effect of DOI (0.01 M) was antagonized by 0.03 M of the 5-HT2 receptor antagonists ketanserin and methiothepin. At concentrations higher than 0.1 M, both antagonists increased on their own the cGMP response elicited by high-K+. This effect was insensitive to tetrodotoxin.It had been previously shown that rat mossy fibre endings release glutamate upon depolarization and that such release can be inhibited by activation of 5-HT2 receptors sited on the mossy fibre endings. Altogether the available data suggest the following conclusions: (a) the glutamate/aspartate endogenously released in cerebellar slices during K+ depolarization increase cGMP synthesis through the activation of both NMDA and non-NMDA receptors; (b) a portion of the cGMP response can be prevented by 5-HT2 receptor activation and may reflect the activity of the mossy fibre-granule cell pathway. Thus serotonin is likely to exert a potent inhibitory control of the excitatory mossy fibre input to the cerebellum by acting at receptors of the 5-HT2 type.
Correspondence to M. Raiteri at the above address 相似文献
104.
Intralesional ethanol in the treatment of unresectable liver cancer 总被引:12,自引:0,他引:12
Tito Livraghi M.D. Sergio Lazzaroni M.D. Franca Meloni M.D. Guido Torzilli M.D. Claudio Vettori M.D. 《World journal of surgery》1995,19(6):801-806
Percutaneous ethanol injection (PEI) under ultrasonography guidance has been widely tried in not advanced hepatocellular carcinoma (HCC). Ten years after the introduction of PEI, some conclusions of its indications can be drawn. In our series, 210 cirrhotic patients were treated; 141 with multisession PEI in an outpatient clinic, 57 with single session PEI under general anesthesia, and 12 with both. The 1-, 3-, and 5-year survival rates (by Kaplan-Meier method) were 93%, 65%, and 41% for Child class A patients with single HCC 5 cm, and 88%, 47%, and 33% for patients with multiple HCC up to five lesions 5 cm. In these patients the local recurrence rate was 15% and the new lesion rate at the 5-year follow-up was 74%. One death due to hemorrhage from esophageal varices in a Child class C patient treated by single session PEI occurred. The large number of cirrhotic patients enrolled in ultrasonography screening programs has created a large demand for effective, safe, repeatable, low-cost treatment that can be offered at many centers. PEI meets all these requirements. PEI is proposed as the treatment of choice for the mentioned patients, excluding candidates for liver transplantation and surgical resection according to the predictive adverse factors currently in use. Single session technique widened the indications of traditional PEI to larger lesions.
Resumen La inyección percutánea de etanol (IPE) bajo guía ultrasonográfica ha sido ampliamente ensayada en carcinoma hepatocelular (CHC) no avanzado. Transcurridos diez años luego luego de la introducción de la IPE, se pueden sacar conclusiones pertinentes a su indicación: En nuestra serie, se trataron 200 pacientes cirróticos, 141 de ellos con IPE en múltiples sesiones en forma ambulatoria, 57 con una sesión única de IPE bajo anestesia generaly y 12 con ambas modalidades. Las tasas de sobrevida a 1, 3 y 5 años (por el método de Kaplan-Meier) fueron 93%, 65%, 41% en los pacientes en clase Child-A con CHC único de 5 cm, y 88%, 47% 33% en CHC múltiple de hasta 5 lesiones de 5 cm. En estos pacientes la tasa de recurrencia local fue 15% y la tasa de nuevas lesiones a los 5 años de seguimiento fue de 54%. Se presentó una muerte por hemorragia de várices esofágicas en un paciente en clase Child-C tratado con una sesión única de IPE. El gran número de pacientes cirróticos incorporados a programas de tamizaje con ultrasonido ha creado una gran demanda por tratamientos eficaces, seguros, reproducibles y de bajo costo. El IPE llena todos estos requerimientos. Se propone el IPE como el tratamiento de escogencia para los pacientes arriba mencionados, haciendo exclusión de los candidatos para transplante hepático y para resección quirúrgica de acuerdo con los factores adversos de pronóstico actualmente en uso. La técnica de une sesión única ha ampliado las significaciones tradicionales del IPE para ser aplicada a lesiones de mayor tamaño.
Résumé L'alcoolisation par injection percutanée (APC) sous échographie est utilisée pour traiter des carcinomes hépatocellulaires (CHC) peu volumineux. Dix ans après l'introduction de la technique d'APC, on peut tirer des conclusions quant à es indications. Dans notre expérience, 210 patients cirrhotiques ont été traités: 141 ont été traités par APC en ambulatoire, 57 en «séance unique» sous anesthésie et 12 par les deux. La survie à 1, 3 et 5 ans (méthode de Kaplan-Meier) était respectivement de 93, de 65 et de 41 % pour les patients ayant une lésion unique 5 cm, classés Child A, et de 88, de 47 et de 33% chez les patients ayant des lésions multiples mais inférieures au nombre de 5, toujours 5 cm. Chez ces patients, le taux de récidive locale était de 15% et le taux de nouvelles lésions à 5 ans, de 74%. Il y a eu un décès par hémorragie en rapport avec une rupture de varices oesophagiennes chez un patient Child C traité en une seule séance d'APC. Le nombre croissant de patients actuellement soumis, à une surveillance par échographie va de paire avec un traitement efficace, sûr, de coût réduit, et facilement disponible dans de nombreux centres. L'APC répond à toutes ces conditions. L'APC peut être proposée comme traitement de choix pour des patients répondant aux critères suscités, en excluant les candidats à la transplantation ou ceux qui peuvent être traités chirurgicalement. Les indications de la technique préconisée ici, en une seule séance, s'élargissent actuellement à des lésions plus volumineuses.相似文献
105.
Background
Gated myocardial perfusion single-photon emission computed tomographic (SPECT) imaging is currently performed by step-and-shoot detector rotation, resulting in acquisition dead time and lengthened study duration compared with nongated SPECT imaging with continuous or pseudocontinuous rotation. Dead time is particularly undesirable in new fast-gated SPECT imaging protocols with inotropic pharmacologic stress.Methods and Results
This article evaluated the influence of projections’ angular spacing on quantitative measurements of left ventricular ejection fraction (LVEF) and perfusion from postexercise 99mTc-labeled sestamibi images. Gated 60-projection data sets from 30 patients were compacted into 30- and 15-projection sets. The three sets (corresponding to 3-, 6-, and 12-degree spacing over 180 degrees) were reconstructed into gated and ungated short-axis image sets. LVEFs were measured from the gated images according to a previously described automatic algorithm, whereas perfusion was assessed from the ungated images by a 20-segment division of their maximal pixel polar maps. LVEF values were essentially unchanged between 60- and 30-projection images (y=0.37+0.996x; r=0.999; standard error of the estimate=0.56) and 60- and 15-projection images (y=1.35+0.987x; r=0.999; standard error of the estimate=0.77) in the 30 patients. Overall, 30- and 15-projection polar maps differed by 1.87%±1.24% and 4.38%±2.25% from the 60-projection polar maps, respectively. Segmental perfusion score agreement between 60- and 30-projection images and between 60- and 15-projection images was 93% (κ=0.92; p<0.001) and 83% (κ=0.81; p<0.001), respectively. Sixty- and 30-projection images were visually undistinguishable, whereas loss of image resolution was noticed in many 15-projection gated and ungated images.Conclusions
Thirty-projection gated SPECT imaging is a practical, accurate, and time-saving approach in standard gated protocols and, potentially, fast-gated protocols. Fifteen-projection gated SPECT imaging is not generally recommended and should be considered only for LVEF assessment in conjunction with fast-gated protocols. 相似文献106.
Pierpaolo Lunardi Luciano Mastronardi Jibril Osman Farah Claudio De Biase Guido Trasimeni Gian F. Gualdi 《Neurosurgical review》1996,19(3):175-178
The case of a young patient with left accessory nerve paralysis is reported. He had slight tilting of the head to the right side, developed over a period of about 6 months. On neurological examination hypotrophy of the left sternocleidomastoid and trapezius muscles was observed. MRI and MR-angiography imaged the presence of a neurovascular compression between the medulla oblungata, at the level of the nerve entry zone, and a vessel loop of an elongated left vertebral artery. In spite of the absence of a surgical demonstration it is our opinion that the neurovascular conflict is the cause of the accessory nerve palsy. 相似文献
107.
Evaluation of vesico-urethral and sweating function in disorders presenting with parkinsonism 总被引:1,自引:0,他引:1
Milena De Marinis Guido Argenta Domenico Mele Antonio Carbone Giulio Baffigo Alessandro Agnoli 《Clinical autonomic research》1993,3(2):125-130
Investigation of vesico-urethral and sweating function was performed in twelve patients with classical idiopathic Parkinson's disease and ten patients with parkinsonism associated with features suggestive of more extensive involvement of the nervous system, as in the Shy—Drager syndrome. The urodynamic studies revealed detrusor hyperreflexia with reduction of maximal cystometric capacity in only one patient with Parkinson's disease (8%), but in nine patients with parkinsonism associated with other features (90%). Urethral sphincter electromyography did not indicate denervation in any patient of either group. Delayed or incomplete relaxation of the urethral sphincter during micturition was observed in seven patients with Parkinson's disease (58%) and in two patients of the other group (20%). Decreased sweating responses were found in both groups of patients when compared with control subjects. Hypohidrosis was more pronounced in parkinsonism associated with other features than in Parkinson's disease. Differences in sweating between the two sides of the body were observed in both groups of patients. Although there are differences in vesico-urethral and sweating function, they do not precisely differentiate between patients with classical Parkinson's disease and those with parkinsonism associated with features suggestive of more extensive involvement of the nervous system. 相似文献
108.
Pietra N Sarli L Maccarini PU Sabadini G Costi R Gobbi S 《World journal of surgery》2000,24(3):345-352
Consensus has never been reached regarding the need or the imaging technique for evaluating the common bile duct (CBD) in
patients considered for cholecystectomy. With the advent of laparoscopic cholecystectomy there has been a resurgence of interest
in the role of preoperative intravenous cholangiography (IVC) as an alternative for evaluating the CBD. The purpose of this
audit was to assess whether a diagnostic workup based on IVC, which permits selective use of intraoperative cholangiography
(IOC) and endoscopic treatment of CBD stones before surgery, could be useful in patients undergoing laparoscopic cholecystectomy
(LC). In patients without jaundice, gallstone pancreatitis, a prior diagnosis of CBD stones, a prior history of contrast allergy,
or a risk of contrast-associated acute renal failure, IVC was performed routinely. Patients suspected to have CBD stones based
on IVC results or with inconclusive IVC and patients with a strong clinical suspicion of CBD stones were referred for endoscopic
retrograde cholangiography (ERC). IOC was carried out in patients who had a history of contrast allergy or risk of contrast-associated
acute renal failure and whenever the surgeon was in doubt as to the biliary anatomy or CBD clearance. IVC was carried out
in 1155 patients, ERC in 225, and IOC in 54. IVC was conclusive in 1132 patients, with a diagnostic accuracy of 99%. Our workup
permitted the sequential endoscopic-laparoscopic treatment of cholecystocholedocholithiasis in 162 cases. During the follow-up
period residual CBD stones were detected in four patients. Our diagnostic workup showed that routine IVC exposes the population
to a large radiation burden, and the cost is high for the small number of patients who benefit. Moreover, it does not seem
helpful in reducing the incidence of CBD injuries during LC. 相似文献
109.
中国南海粗疣棘柳珊瑚中倍半萜成分研究 总被引:1,自引:0,他引:1
目的:对采自中国南海的粗疣棘柳珊瑚(Acanthogorgia vagae)的化学成分进行研究,从中寻找有生物活性的次生代谢产物。方法:用硅胶柱层析对粗疣棘柳珊瑚的乙醚提取物进行分离纯化;根据其化学性质,结合现代波谱技术(MS,NMR等),对得到的化合物进行结构鉴定。结果:分离得到4个呋喃倍半萜化合物,其结构分别鉴定为1indenene(1),1indestrene(2),bebryazulene(3)及franodiene(4)。结论:本文系首次对该珊瑚化学成分进行研究;4个倍半萜成分亦均为首次从该生物中分离得到。其中,1indenene(1)的碳谱数据为首次报道,并首次对化合物1indenene(1)及franodiene(4)氢谱数据进行了全归属。另外,对文献报道的bebryazulene(3)及franodiene(4)的碳谱数据进行了童新归属. 相似文献
110.
Prognostic impact of ANX7-GTPase in metastatic and HER2-negative breast cancer patients. 总被引:4,自引:0,他引:4
Meera Srivastava Lukas Bubendorf Mark Raffeld Christoph Bucher Jochen Torhorst Guido Sauter Cara Olsen Olli P Kallioniemi Ofer Eidelman Harvey B Pollard 《Clinical cancer research》2004,10(7):2344-2350
PURPOSE: ANX7-GTPase located on chromosome 10q21 is significantly altered and associated with hormone-refractory metastatic prostate cancers. Therefore, we investigated whether levels of ANX7 correlate with breast cancer progression and survival EXPERIMENTAL DESIGN: A diagnostic tumor tissue microarray containing 525 human breast tissue specimens at different stages of the disease was assayed for ANX7 using immunocytochemical methods with ANX7 monoclonal antibody. A separate prognostic tumor tissue microarray containing 553 human breast tissue specimens annotated with clinicopathological parameters was assayed for ANX7, HER2, estrogen receptor, progesterone receptor, and p53 protein. RESULTS: We report here for the first time that the expression of ANX7-GTPase is significantly enhanced and associated with the presence of metastatic disease (P < 0.0001) in the 525 human breast tissue specimens analyzed. Furthermore, using a separate 553 case retrospective prognostic tumor tissue microarray, we found that increased ANX7 expression is also significantly associated with poor overall patient survival (P < 0.014). This is particularly true when restricted to patients in whom the BRE clinical grade is 2 (P < 0.001) or for whom there is a lack of HER2 expression (P < 0.002). Finally, Cox regression analysis shows that as the expression of ANX7 rises, the probability of survival decreases by more than 10-fold for those patients with HER2-negative tumors. These latter patients represented 66% of the population affected with breast cancer in this study. CONCLUSIONS: High levels of ANX7 in tumor correlate strongly with poor survival of HER2-negative patients and the most aggressive forms of breast cancer. This is the first study to demonstrate that ANX7 antibody has the potential for development into an in vivo diagnostic and therapeutic tool. This simple and reliable immunohistochemical assay may therefore become an important biomarker for metastatic breast cancer diagnosis and management of HER2-negative breast tumor patients. 相似文献