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61.
ObjectiveTo investigate the potentials of the root bark of Annona (A.) senegalensis in the control of seizure and related hypnotic and motor incoordination effects in mice using experimental models.MethodsThe methanol extract (ME) of the root bark of A. senegalensis was studied in mice using pentylenetetrazole (PTZ) induced convulsions, phenobarbitone induced sleeping time and motor coordination test on rota-rod performance. Acute toxicity and lethality (LD50) test as well as phytochemical analysis were also carried out.ResultsThe extract (200, 400, 800 mg/kg) exhibited a non-dose dependent significant (P <0.05) delay in the onset of both tonic and clonic phases of seizure induced by PTZ (60 mg/kg, s.c.) as well as offered a 100% protection (200 mg/kg) in mice from PTZ induced seizures. The extract significantly (P <0.05) decreased the latency and increased the duration of phenobarbitone induced sleeping time. At 200 mg/kg, the extract exhibited a significant (P <0.05) motor incoordination. The acute toxicity test revealed an oral LD50 of 1 296 mg/kg, while the phytochemical studies showed the presence of alkaloids, resins, glycosides, carbohydrate, reducing sugar, flavonoids, terpenoids, saponins and tannins.ConclusionThe extract of A. senegalensis possessed anticonvulsant activity with pronounced hypnotic and muscle relaxant effects. 相似文献
62.
We have read the recent comprehensive review by Cruz et al.[1] regarding the targeting of receptor tyrosine kinases andtheir therapeutic perspectives in head and neck squamous cellcarcinomas (HNSCC). The major focus of this report was epidermalgrowth factor receptor (EGFR) biology and targeting. However,we feel 相似文献
63.
FJ Weir A Smith P Littleton N Carter PA Hamilton 《Acta paediatrica (Oslo, Norway : 1992)》1992,81(9):672-675
The aim of this study was to measure plasma atrial natriuretic peptide in preterm infants with a patent ductus arteriosus before and after closure with indomethacin. Atrial natriuretic peptide was measured in 28 preterm infants with clinical and echocardiographic evidence of a patent ductus arteriosus and in eight preterm infants who did not develop clinical evidence of a patent ductus arteriosus. Plasma concentration of atrial natriuretic peptide was measured by radioimmunoassay. In 18 infants the patent ductus arteriosus closed after one course of indomethacin; atrial natriuretic peptide levels decreased from median 1240 pg/ml (range 201-5483 pg/ml) to 266 pg/ml (range 62-1108 pg/ml). In four infants the patent ductus arteriosus closed after two courses of indomethacin and two infants had surgical ligation after indomethacin treatment failed. The patent ductus arteriosus closed spontaneously in four infants (atrial natriuretic peptide median level 152 pg/ml, range 61-495 pg/ml). In the eight infants without patent ductus arteriosus, atrial natriuretic peptide level was median 224 pg/ml (range 38-876 pg/ml). Measurement of plasma atrial natriuretic peptide concentration has a role in predicting when indomethacin treatment is indicated. 相似文献
64.
目的探讨单核细胞向巨噬细胞分化过程中CD44 mRNA表达和黏附功能的变化。方法应用豆蔻佛波醇乙酯(PMA)诱导单核细胞系U937向巨噬细胞分化;应用RT-PCR分析U937细胞CD44 mRNA表达变化,并以β-actin作为内参进行半定量评价,并对主要条带进行测序;应用荧光染料BCECF/AM作为探针,测定黏附于激活的内皮细胞上的U937细胞数目。结果与对照组比较,PMA诱导的U937细胞CD44 mRNA总体表达显著增加(P=0.01037),异构体/标准CD44比例显著上升(P=0.0005551),测序结果显示PMA刺激后显著增加的是947 bp(V8 V9 V10)和1208 bp(V7 V8 V9 V10)CD44异构体。同时,PMA刺激后U937细胞黏附功能显著增加(P=0.0029)。结论单核细胞向巨噬细胞分化过程中CD44 mRNA,特别是947bp(V8 V9 V10)和1208 bp(V7 V8 V9 V10)CD44异构体的表达显著增加,可能与细胞黏附功能的增强相关。 相似文献
65.
MT Bardella N Molteni L Prampolini AM Giunta AR Baldassarri D Morganti PA Bianchi 《Archives of disease in childhood》1994,70(3):211-213
The use of follow up studies was evaluated in 128 patients with coeliac disease during their first visit to a department for adults. The original diagnosis had been made in childhood in all patients. Fifty eight (45%) of the subjects were following a gluten free diet, 23 (18%) were following a gluten free diet but with occasional gluten consumption, and 47 (37%) had adopted an unrestricted, gluten containing diet for a mean of 11.2 years. There was no correlation in individual subjects between the presence of symptoms, biochemical and immunological abnormalities, severity of histological findings, and the amount of dietary gluten, despite the greater frequency of symptoms in the group following an unrestricted diet than in the other two groups. Short stature and epilepsy with cerebral calcifications only occurred in patients following an unrestricted diet. As only diagnosis based on two or three biopsy samples and regular follow up correlated positively with dietary compliance, it is suggested that a histologically confirmed diagnosis of coeliac disease and regular lifelong follow up are essential in the management of these patients. 相似文献
66.
MJ Evans PA McKeever GA Pearson D Field RK Firmin 《Archives of disease in childhood》1994,71(2):F88-F92
The pathology was reviewed of the early deaths identified from the first 50 neonates treated with extracorporeal membrane oxygenation (ECMO) during its introduction to the UK. Fifteen neonates died during or shortly after ECMO between August 1989 and June 1992. Data on 12 are presented (three did not have a postmortem examination). The clinical diagnoses at referral for ECMO were as follows: persistent pulmonary hypertension of the newborn (six infants), primary congenital pneumonia (one infant), community acquired pneumonia (two infants), birth asphyxia (one infant), respiratory distress syndrome (one infant), and meconium aspiration syndrome (one infant). In our group, at necropsy, five had significant haemorrhage (three intracranial, one pulmonary, one pericardial and intraventricular). Three of five infants with evidence of haemorrhage also had signs of sepsis. Six infants had evidence at necropsy of systemic sepsis, five showed evidence of severe anoxic brain injury, and four infants had cerebellar haemorrhages. Three infants had evidence of myocardial ischaemia. It is difficult to discriminate between the relative influence of the primary diagnosis, the mode of treatment, and the severity of presentation in the genesis of this pathology. It is likely that the extent and severity of some of the findings represent a pathological progression that would have been interrupted by the death of the patient, had ECMO not been instituted. 相似文献
67.
68.
Summary Forty three patients, admitted to the department of Neurological Surgery for management of central nervous system tumours, were studied pre-operatively for serum myelin basic protein immunoreactivity as a marker of central nervous system lesion and for circulating immunoglobulins and complement (C3) levels. Myelin basic protein concentration did not appear to correlate with tumour type or grade. Serum immunoglobulin levels were found to be within the normal range but the mean IgM level was significantly higher in the glioma group when compared with meningiomas. 相似文献
69.
70.
Summary— With respect to the heart, the prolonged existence of hypertension, both in man and in experimental animals is predominantly characterized by an increase in left ventricular myocardial mass. In this process, the autonomic nervous system plays an important role. Although endogenous catecholamine stimulation of the heart is mainly exerted via the β-adrenoceptors, in several mammalian species, the stimulation of cardiac α-adrenoceptors also mediates positive inotropic actions. We investigated the functional responses of isolated hypertrophied hearts taken from spontaneously hypertensive rats (SHR) and rats with an induced aortic stenosis (ASR) to various α1 -adrenoceptor agonists and compared them with those from age matched Wistar Kyoto (WKY) and "sham" operated controls. Accordingly, we studied the functional response to: methoxamine (α1 ), cirazoline (α1 ) and phenylephrine (α1 > β1 ). The inotropic response to the α1 -adrenoceptor agonists cirazoline and methoxamine proved to be significantly weaker in hypertrophied hearts from SHR and ASR than in non-hypertrophied hearts from WHY and "sham" operated controls ( p < 0.05). The inotropic response to phenylephrine remained intact in hypertrophied myocardial tissue. However, it was significantly reduced when the hearts were pre-treated with the intracellular Ca2+ -antagonists ryanodine and TMB-8. These findings show that the mechanism of sarcolemmal Ca2+ release, activated by phenylephrine, is still intact in the hypertrophied myocardial cell. In conclusion, these data show that cardiac hypertrophy, be it of genetical or mechanical origin, leads to a reduced response of the isolated heart to α1 -adrenoceptor stimulation. 相似文献