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991.
Programmed atrial stimulation at five atrial sites was performed to evaluate electrophysiologic atrial properties in 17 control patients (14 M, 3F, mean age 61 +/- 9 years) (Group A) and in 18 patients with paroxysmal atrial fibrillation (13 M, 5 F, mean age 61 +/- 5 years) (Group B) with normal sinus node function. The mean value of the P wave duration was similar in both groups. Programmed atrial stimulation was performed at five atrial sites: high, medium and low lateral wall, and high and low medial wall. We evaluated the following parameters: A) local conduction delay measured at the functional refractory period as the difference between A1-A2 and S1-S2 intervals; B) widening of local electrogram measured at the functional refractory period as the difference between A1-A2 interval measured at the end of each local electrogram and A1-A2 interval measured at the beginning of each local electrogram. We evaluated the mean and the maximum value of the two above-mentioned parameters; C) dispersion of effective refractory period and functional refractory period, determined as the longest minus the shortest refractory period from the range of refractory periods measured in each patient; D) the mean of effective refractory periods and functional refractory periods observed at five atrial sites. Mean and maximum local conduction delay, mean effective and functional refractory periods did not present significant differences in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
992.
New 2,5-dialkylpyrrolidines found in the venom of Monomorium indicum include trans-2-butyl-5-(4-pentenyl)pyrrolidine [1], trans-2-butyl-5-(6-heptenyl)pyrrolidine [4], trans-5-(5-hexenyl)-2-(4-pentenyl)pyrrolidine [6], trans-5-(6-heptenyl)-2-(5-hexenyl)pyrrolidine [8], and trans-5-heptyl-2-hexylpyrrolidine [16], whose structures were confirmed by synthesis. The concomitance of five previously reported trans-2,5-dialkyl-pyrrolidines along with small amounts of the cis isomers and N-methyl analogues makes the venom of M. indicum the most qualitatively diverse blend of alkaloids reported from an ant to date. The toxicities to termites of four of these alkaloids were determined.  相似文献   
993.
Forty samples of cord blood lymphocytes were isolated from 40 normal healthy full-term newborns. The initial 20 samples were used to determine the dose-response curve of three different thymic extracts (TP-1, bovine thymic extract; TG-15-I and TG-15-II, both porcine thymic extracts) and one of renal origin (KG-1) as a control of non-lymphoid organ extract, by measuring the E-rosette T cells. Results showed that E-rosette T cells increased significantly when the thymic extract concentration was increased to 12.5 micrograms/ml. However, there was no statistical difference between TP-1, TG-15-I and TG-15-II in the increase of E-rosette-forming cells. The remaining 20 samples were preincubated with 0, 12.5, 25 or 50 micrograms/ml of thymic extracts. It was observed that the lymphoproliferation, interleukin-2 (IL-2), gamma-interferon (IFN-gamma) and tumor necrotic factor (TNF) production were all significantly increased after thymic extract treatment. No statistical difference between these three thymic preparations in the stimulation of lymphoproliferative response was found. However, among the three thymic extracts, TP-1 appears to induce the highest amounts of IL-2, IFN-gamma and TNF. Of the TG-15-I and TG-15-II, the former stimulates higher IL-2 production whereas the latter enhances IFN-gamma and TNF production. The different immunostimulating effects and potencies that these three thymic extracts showed may reflect not only the species difference but also the difference in preparation procedures. Different components in these thymic extracts may be responsible for different biological activities. Results from these comparative studies may provide useful information in future clinical trials for the treatment of the primary immunodeficiency diseases according to their pathogenesis and may also indicate a possible beneficial effect of the combination of chemotherapy and thymic extracts.  相似文献   
994.
In summary, factors to consider in treatment are (1) the patient's age; (2) the flexibility of the condition; (3) the severity of deformity; (4) the presence of equinus; (5) abnormal shoe wear; and (6) the symptoms. When a child presents with severe flexible flatfoot one should rule out an underlying neuromuscular disorder and perform a complete biomechanical evaluation to ascertain any rotational or angular conditions of the legs that might influence the treatment. If a child is in group 1 (ages 4 to 7), a Helfet heel seat with a medial plantar wedge is usually adequate treatment. In the group II (ages 8 to 12) adolescent with flexible flatfoot, more control of the calcaneal eversion is needed. This is obtained by using a device constructed from a plaster mold taken while the foot is in neutral position. This UCBL type of device must usually extend to the metatarsal heads and be elevated on the medial and lateral sides. The group III (ages 13 to 17) adolescent usually has the additional problem of a forefoot varus, which must be controlled using a forefoot post. It is also not unusual to have to add additional wedging inside the heel of the shoe to invert the heel.  相似文献   
995.
Mycobacterium ulcerans infection in Ashanti region, Ghana   总被引:1,自引:0,他引:1  
We describe a series of 96 cases of Mycobacterium ulcerans infection (Buruli ulcer) from a new endemic focus in the Afram valley, north of Agogo, in Ghana. 63 cases were children under 13 years old. Active treatment by excision and skin grafting necessitates long stays in hospital and repeated procedures. Scarring and contracture are frequent. Eyes and other vital organs may be destroyed. In its endemic foci Buruli ulcer is a serious health burden on rural populations. Research is urgently needed, especially in prevention and non-surgical management.  相似文献   
996.
997.
998.
Alterations in the pulmonary surfactant system are partly responsible for the respiratory insufficiency seen with acute pancreatitis. In this model of cerulein-induced pancreatitis in rats, we utilized a new stable isotope metabolic tracer technique to examine one aspect of the pulmonary surfactant system and its relationship to associated lung injury. We have demonstrated primary, early depression of lung phospholipid synthesis reflected in both lung tissue and alveolar washings. We suggest that this quantitative change in pulmonary surfactant synthetic rate may partly explain the occurrence of respiratory failure with acute pancreatitis.  相似文献   
999.
W C Edwards  T J Orme  G Orr-Edwards 《Spine》1987,12(8):792-795
The purpose of this study is to analyze the prognostic value of discography followed by lumbar CT scanning in the selection of patients for chemonucleolysis. The overall success rate of chemonucleolysis in this series of 50 patients were 72%. The best results were obtained when the herniated disc fragment demonstrated a large uptake of contrast material visible by CT discography. The success rate of chemonucleolysis in this group of patients was 95%. Conversely, when the herniated fragment demonstrated no uptake of contrast material by CT discography, the success rate of the chemonucleolysis was 16%.  相似文献   
1000.
The value of maternal C-reactive protein (CRP) levels as predictors of fetal and maternal infective morbidity and fetal mortality was assessed prospectively over a 6-month period in all cases of premature rupture of the fetal membranes or suspected premature labour. Statistical analysis of results showed that CRP at a level of 1.32 mg/dl is a sensitive marker of infective morbidity in mother and neonate. Furthermore, there was a significant association between raised CRP levels and low-birth-weight babies, suggesting that intra-uterine infection is a major cause of prematurity in the study population.  相似文献   
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