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101.
The effects of the phenylalkylamines verapamil, gallopamil, and devapamil on L-type calcium currents (ICa) were studied in ventricular myocytes from rat hearts using the whole-cell patch-clamp technique. In particular, the question was addressed, whether the pharmacological binding sites for these drugs were located at the inner and/or at the outer surface of the cell membrane. Therefore, tertiary verapamil, gallopamil, and devapamil and their corresponding quaternary derivatives were applied either from the outside or the inside of the cell membrane. Extracellular application of verapamil, gallopamil and devapamil (each at 3 M) reduced Ica to 16.1 ±8.6%, 11 ± 8.9 %, and 9.3 ± 6 % of control, respectively. Intracellular application of the same substances, via the patch pipette filled with 30 M of either verapamil, gallopamil, or devapamil, failed to depress ICa. The quaternary derivatives of the phenylalkylamines (30 M) were ineffective both when applied extracellularly or intracellularly. It is suggested that phenylalkylamines block ICa in ventricular myocytes by acting on a binding site of the calcium channel molecule located at the outer surface of the cell membrane. 相似文献
102.
Comparison of transarterial and multiple nerve stimulation techniques for axillary block using a high dose of mepivacaine with adrenaline 总被引:2,自引:0,他引:2
Koscielniak-Nielsen ZJ Nielsen PR Nielsen SL Gardi T Hermann C 《Acta anaesthesiologica Scandinavica》1999,43(4):398-404
BACKGROUND: High-dose transarterial (TA) technique results in high effectiveness of the axillary block. The technique is fast and simple, but does not produce a satisfactory success rate when using the manufacturer's recommended dose of mepivacaine. The multiple nerve stimulation (MNS) technique requires more time and experience. This double-blind study compared effectiveness, safety and the time used to obtain an effective analgesia in 101 patients, having an axillary block by either TA or MNS techniques. METHODS: Mepivacaine with adrenaline (MEPA), 850 mg, was used for the initial block. Five millilitres of 1% solution was injected subcutaneously. In the TA group, 20 mL of 2% solution was injected deep to, and 20 mL superficial to the axillary artery. In the MNS group, four terminal motor nerves were electrolocated in the axilla, and injected with 10 mL each. Analgesia was assessed every 10 min and, when needed, supplemented after 30 min. The block was effective when analgesia was present in all sensory nerve areas distal to the elbow. RESULTS: The MNS group required median 11 min for block performance compared with 8 min for the TA group (P < 0.001). Latency of the initial block was shorter and the frequency of supplemental analgesia lower in the MNS group (median 10 min and 6%) than in the TA group (30 min and 36%, respectively), P < 0.001. All incomplete blocks were successfully supplemented. However, the total time to obtain an effective block was shorter in the MNS group (23 min) than in the TA group (37 min), P < 0.001. Two patients in each group had signs and symptoms of systemic toxicity, the most serious being atrial fibrillation and temporary loss of consciousness in a cardiovascularly medicated patient. The local adverse effects (intravascular injections and haematomas) were fewer in the MNS group, P < 0.001. CONCLUSION: The MNS technique of axillary block by four injections of 10 mL of 2% MEPA produces faster and more extensive block than the TA technique by two injections of 20 mL. Therefore, the MNS technique requires fewer supplementary blocks and results in faster patient readiness for surgery. However, high doses of MEPA may result in dangerous systemic toxic reactions. 相似文献
103.
Intracerebral extension of Wegener's granulomatosis (WG) is rare. We present a patient with oculomotor and trochlear nerve
palsy with histologically proved WG. An MR examination revealed granulomatous tissue in nasal cavity, paranasal sinuses with
meningeal infiltration, and uncommon penetration into cavernous sinus and sella turcica. The MR images before and during pharmacological
therapy are presented.
Received: 14 July 1998; Revision received: 12 October 1998; Accepted: 13 January 1999 相似文献
104.
Quality-of-Life Outcome After Laparoscopic Adjustable Gastric Banding for Morbid Obesity 总被引:3,自引:0,他引:3
Background: The definition of success and failure of a bariatric procedure should include weight loss as well as improvement
of comorbidity and quality-of-life (QoL) assessment. QoL measures changes in physical, functional, mental, and social health
in order to evaluate benefits of new programs and interventions. Material and Methods: From April 1995 until March 1999, 287
patients underwent laparoscopic adjustable silicone gastric banding (LASGB) at Northwest Hospital Frankfurt a.M. (Germany).
In this study, 100 of 287 patients (preoperative mean BMI 48.3 kg/m2; mean age 35.2 years) with a follow-up >18 month were evaluated. All patients underwent anonymous questionnaire (26 questions
with a maximum score of 60) about different aspects of QoL outcome after LSAGB. Results: In this study, 4 of 100 patients
refused to give an answer to the QoL questions. Therefore 96 patients were evaluated. The QoL auto-evaluation of the patients
shows that QoL generally improved after surgery in 92%. Using the scoring system, 44% of patients have excellent, 52% good,
and only 4% bad results. The 4 patients who refused had to be classified as failure. General acceptance of LSAGB is wide,
but gastrointestinal side effects are recognizable in more than 78% of operated patients. Successful weight loss is followed
by an improvement of comorbidities. Conclusions: Safe, effective bariatric procedures increase the quality of life in morbidly
obese patients markedly. Bariatric surgeons are committed to support and help their patients until they reach a new quality
of life after obesity surgery. 相似文献
105.
Lesion-remote metabolic changes were examined 1-7 days after neocortical cold injury using tissue ATP, glucose and lactate bioluminescent imaging, pH-dependent fluoroscopy and cerebral protein synthesis (CPS) autoradiography. One day after lesioning an alkaline pH shift (0.35 +/- 0.19 units above contralateral) was noticed in the lesion-remote cortex, the underlying white matter, the striatum, hippocampus and thalamus, which slowly resolved within 7 days and probably reflected the spread of vasogenic edema. Closely associated with the pH shift, elevations in tissue glucose and lactate levels were found, which reached maximum levels after 3 days (7.4 +/- 2.4 vs 4.2 +/- 1.2 micromol/g glucose, 6.6 +/- 2.3 vs 2.1 +/- 0.6 micromol/g lactate) but, in contrast to the alkalosis, remained elevated after 1 week. Thus, neocortical trauma is associated with long-lasting metabolic changes, which are intimately linked with the distribution of post-traumatic alkalosis. 相似文献
106.
Testicular peritubular cells are located in the lamina propria of seminiferous tubules. These cells, significantly contributing to the basal membrane of seminiferous epithelium, have been studied in a number of species. However, there is a lack of data on the development of the lamina propria in the human testis. The aim of our survey was to investigate the characteristics of the lamina propria and, in particular, peritubular cells in the fetal human testes by immunohistological and stereological methods. Therefore, testes (14–39 weeks of gestation, n=45) were dissected and fixed in a 4% buffered paraformaldehyde solution. Several pieces of each testis were embedded in paraffin and processed for immunohistochemical and stereological analysis. All investigated testes have shown sex cords in the process of development and differentiation. Morphologically, peritubular cells in the lamina propria can be divided into two types: fibroblast-like (FL) and myoid-like (ML) type (cells which much resemble mature myoid cells). By immunohistochemistry, both FL and ML cells are found to be strongly positive for the intermediate filament desmin, but negative for -smooth actin. While FL cells intensively express Ki-67 demonstrating proliferative activity, ML cells are found to be negative. The basement membrane of sex cords as well as the blood vessels of the interstitium show strong positivity to collagen IV and laminin. Concerning the correlation between the appearance of the investigated antigens with the gestational age, all antigens have been expressed (in the manner described above) already in the 14th week of gestation. The stereological analysis of the number (Nv) and volume (Vv) of peritubular cells indicates a pulsatile development of these cells in the lamina propria of the human fetal testis. While the stereological variables determined for FL cells show a gradual decrease, the same variables determined for ML cells demonstrate a successive increase. It appears that the lamina propria of the fetal human testes shares many of the properties previously discovered in rodents. 相似文献
107.
From 1985 to 1988, a state-wide program of cancer education was offered to community-based allied health professionals (AHPs) at five different program sites in Pennsylvania. During this three-year period, 512 social workers, clergy, dieticians, physical therapists and others received training to increase their knowledge about cancer and counseling, improve their supportive attitude regarding cancer patients and families, and decrease stress related to their work with this population. Overall, the Program was successful in reaching AHPs working with cancer clients who had little formal training in the cancer field. At the beginning of training, it was observed that AHPs with initially higher levels of education and more years of work experience with cancer patients had higher levels of counseling knowledge. Those who were women, worked in hospitals, or had worked with cancer patients longer exhibited higher levels of cancer knowledge. Participants who were women and who had more education had reported lower levels of job stress. Among those AHPs who completed the training courses, cancer knowledge increased by 14 percent. In addition, knowledge related to counseling cancer patients and their families improved by 11 percentage points. Perceived job stress among the AHPs also declined by 10 percent. Finally, participant supportive attitude concerning cancer clients improved. 相似文献
108.
Ulrich Jahnel Hermann Nawrath Rikuo Ochi 《Naunyn-Schmiedeberg's archives of pharmacology》1992,345(5):564-569
Summary In guinea-pig atrial myocytes, the effects of the adenosine analogue 5-(N-ethyl)-carboxamido-adenosine (NECA) in the presence of isoprenaline (ISO) on Ca2+ channel activity were analyzed. Single Ca2+ channel currents were recorded from cell-attached patches by application of several hundred 100 ms depolarizing steps. Under control conditions, burstlike activity of channel openings during some depolarizing steps were followed by variably long periods of quiescence (blank sweeps). During superfusion with ISO (100 nmol/l), ensemble-averaged (mean) current was increased by about 150%. The underlying mechanism was found to be a significant increase in the channel availability, defined as the ratio of current-containing sweeps to the total number of sweeps. In addition, the ISO-induced reduction of blank sweeps was combined with slightly but not significantly higher values of the open probability in the current-containing sweeps. Open time and shut time histograms could be fitted by single and double exponential curves, respectively, which remained rather unaffected in the presence of ISO; accordingly, mean open time and mean shut time of the channel were not significantly changed by ISO. After the addition of NECA (1 mol/l) in the presence of ISO, the ISO-induced increase in mean current was abolished. This effect of NECA on mean current was due to a reduction of the channel availability and a slight decrease in the open probability. The purinoceptor blocking agent 8-phenyltheophylline (10 mol/l) antagonized the inhibitory action of NECA on the ISO-induced increase in Ca2+ channel activity. These results indicate that -adrenoceptor-induced changes in Ca2+ channel activity are counteracted by stimulation of, presumably, A1 adenosine receptors. This may be explained by the fact that purinoceptors, beside their stimulating action on K+ channels, mediate an additional inhibitory effect on the adenylate cyclase system in the atrium. Subsequently, purinoceptor activation reverses the ISO-induced increase in Ca2+ channel activity due to a reduction in cAMP content leading to a decrease in the number of phosphorylated Ca2+ channels.
Send offprint requests to U. Jahnel at the above address 相似文献
109.
Christoph Kaiser Felix Bergel Ekkehard Doehring-Schwerdtfeger Hermann Feldmeier Jochen H. H. Ehrich 《Pediatric nephrology (Berlin, Germany)》1992,6(2):145-148
Semi-quantitative urinalysis with urine reagent strips (URS) for erythrocyturia (EU), leucocyturia (LU) and proteinuria (PU) was performed in Congolese and Sudanese school children withSchistosoma haematobium and/orS.mansoni infection. Quantitative urinalysis was performed on the same specimen using microscopy and a Neubauer counting chamber for EU and LU and the Coomassie blue dye-binding assay for PU. Microscopically detectable EU of more than 10 cells/l was found in 63% of all samples and LU of more than 20 cells/l was found in 60% of all samples. With the Coomassie blue method, PU of more than 150 mg/l was detected in 51% of all samples. URS gave positive results of grade 1–3 for EU in 69% of all samples, for LU in 63% of all samples and for PU in 66% of all samples. The sensitivity and specificity of URS compared with standard reference methods were as follows: EU 95% and 75%, LU 81% and 81% and PU 90% and 56%. When the results of all three test were combined, URS differentiated abnormal from normal urine specimens with a sensitivity of 94% and a specificity of 70%. Median quantitative results showed a good correlation with semiquantitative URS readings for all parameters, but there was a wide range of URS scores.We concluded that URS sensitively detect urinary abnormalities and thus may be used as a general screening method under field conditions when more specific methods cannot be performed. In the hospital laboratory,urine microscopy with a counting chamber would be preferred to URS as a sole method for EU and LU detection; URS is useful for the detection of PU in the tropical hospital laboratory where an appropriate quantitative method with a better specificity may not be available. 相似文献
110.
Klinische und feinmotorische Therapiekontrolle bei Morbus Wilson 总被引:1,自引:0,他引:1
At the time of diagnosis and after therapy, we examined 33 patients suffering from Wilson's disease. We applied a standardized diagnostic score system on the basis of clinical signs. Without observing any differences between pseudoparkinsonian and pseudosclerosis subtypes, patients with neurological symptoms significantly improved by 2.33 points. Patients with initially more severe symptoms showed the same improvement as less affected patients. Fine motor disturbances were evaluated using the V-scope system. Finger tapping and drawing a spiral were compared to values of a healthy control group (n = 52). Patients with neurological symptoms showed significantly decreased frequencies in both tests. The clinical score was related to frequencies in finger tapping but not in drawing a spiral. Therefore finger tapping can be used as an objective diagnostic tool to evaluate the severity of Wilson's disease, while spiral testing appears to be a sensitive screening tool. 相似文献