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排序方式: 共有2212条查询结果,搜索用时 15 毫秒
91.
Jos M. Oliveira Pedro Oliveira Raymond L. Baumes Odete Maia 《Journal of food composition and analysis》2008,21(8):695-707
Changes in volatiles during maturation in bottles of monovarietal Vinhos Verdes wines from Loureiro and Alvarinho grape varieties, were followed by chemical and sensory analyses. Young wines and wines matured for 8 and 20 months were studied. The volatiles were determined by gas chromatography–mass spectrometry (GC-MS) after extraction on XAD-2 resin. Straight chain fatty acid ethyl esters and acetates of fusel alcohols decreased quicker for Loureiro wine, while the increase in ethyl esters of branched fatty acids was similar for both varieties. Linalool, Ho-trienol, α-terpineol and β-damascenone could be used to differentiate between each variety. However, linalool decreased to negligible values after 20 months of maturation. β-Damascenone decreased but remained high enough to be useful for differentiating each variety. Sensory analysis indicated a decrease of tropical fruit and tree fruit characters with conservation time for Alvarinho wine, and the opposite for Loureiro; moreover, citrus fruit character decreased in both varieties. 相似文献
92.
93.
The Brugada syndrome is a rare condition, and due to its mutating manner of presentation it may be difficult to diagnose. We report one case and discuss the diagnostic aspects and the clinical outcome of one patient with characteristic findings of this syndrome. These findings are especially defined by J-ST elevation in the right leads of serial electrocardiographic records, wide oscillations of J points and ST segments during 24-hour Holter monitoring, and nocturnal sudden death. We stress the importance of the Holter monitor findings for diagnostic complementation. Through this method it is possible to establish a correlation between vigil activities and sleep and the variability of the degree of impairment in ventricular repolarization. 相似文献
94.
A case report of a dramatic therapeutic response of Hodgkin's disease (HD) to diethylstilbestrol (DES) in a man who was being treated for concurrent prostate cancer suggested that there also may be a role for sex steroids in the pathogenesis of HD (1). High levels of estrogen receptors (ER) comparable to those seen in breast carcinoma cells were detected in that patient's Hodgkin's biopsy specimen. In order to determine whether this patient was unique or whether sex steroid receptors commonly are present in HD specimens, we examined expression of ER and progesterone receptors (PR) in diagnostic tissue from pediatric (n = 14) and adult (n = 41) patients with HD using immunohistochemistry. None of the 55 samples expressed PR. 16/55 (29%) demonstrated weak nuclear ER positivity, which was confined to germinal center and occasional mantle zone lymphocytes and was comparable to that seen in non-malignant control lymph nodes. (4/5)5 (7.3%) samples exhibited moderate positivity in Reed Sternberg cells, which in one case was nuclear. ER commonly are expressed weakly in some HD tumors unrelated to clinical stage or patient sex but are generally limited to germinal center and mantle zone lymphocytes. A rare patient displays moderate cytoplasmic or nuclear ER in Reed-Sternberg cells. 相似文献
95.
Lahlou S Magalhães PJ de Siqueira RJ Figueiredo AF Interaminense LF Maia JG Sousa PJ 《Journal of cardiovascular pharmacology》2005,46(4):412-421
Cardiovascular effects of intravenous (i.v.) treatment with the essential oil of the bark of Aniba canelilla (EOAC) were investigated in normotensive rats. In both pentobarbital-anesthetized and conscious rats, i.v. bolus injections of EOAC (1 to 20 mg/kg) elicited similar and dose-dependent hypotension and bradycardia. Pretreatment of anesthetized rats with bilateral vagotomy significantly reduced the bradycardia without affecting the hypotension. In conscious rats, pretreatment with hexamethonium (30 mg/kg, i.v.) significantly reduced the EOAC-induced bradycardia without affecting the hypotension. The opposite effect was observed after i.v. pretreatment with the nitric oxide synthase inhibitor, N-nitro-L-arginine methyl esther (L-NAME, 20 mg/kg). However, both EOAC-induced hypotension and bradycardia were significantly reduced by pretreatment with methylatropine (1 mg/kg, i.v.). In rat endothelium-containing aorta preparations, EOAC (1-600 microg/mL) induced a concentration-dependent reduction of potassium (60 mM)-induced contraction [IC50 (geometric mean+/-95% confidence interval)=64.5 (45.6-91.2) microg/mL)], an effect that was significantly reduced by the addition of atropine (10 microM) in the perfusion medium [IC50=109.5 (72.5-165.4) microg/mL)]. Furthermore, the vasorelaxant effects of the EOAC were also but significantly reduced [IC50=139.1 (105.2-183.9) microg/mL)] by removal of the vascular endothelium. Furthermore, the CaCl2-induced contractions in calcium-free medium were reduced and even fully abolished by EOAC (100 and 600 microg/mL), respectively. However, EOAC (600 microg/mL) was without significant effect on caffeine-induced contractions in calcium-free medium. These data show that i.v. treatment of rats with EOAC induces dose-dependent hypotension and bradycardia, which occurred independently. The bradycardia appears mainly dependent upon the presence of an operational and functional parasympathetic drive to the heart. However, the hypotension is due to an active vascular relaxation rather than withdrawal of sympathetic tone. This relaxation seems partly mediated by an endothelial L-arginine/nitric oxide pathway through peripheral muscarinic receptor activation (endothelium-dependent relaxation) and predominantly through an inhibition of calcium inward current (endothelium-independent relaxation). 相似文献
96.
Falcó JL Lloveras M Buira I Teixidó J Borrell JI Méndez E Terencio J Palomer A Guglietta A 《European journal of medicinal chemistry》2005,40(11):1179-1187
Among the known non-benzodiazepinic hypnotic drugs acting on the alpha1 subunit of the GABA-A receptor, Zolpidem, Zaleplon and Indiplon have showed high affinity and selectivity. Following a design methodology including pharmacophoric requirements and ADME-predicted properties, we have synthesized a library of 3-amino-4,5-dihydro-1H-pyrazolo[3,4-b]pyridin-6(7H)-ones and their N1-alkyl derivatives as new scaffolds for designing non-benzodiazepine BZ receptor ligands. 相似文献
97.
98.
Carvalho AA Vieira A Simplício H Fugygara S Carvalho SM Rigueiro MP 《Arquivos de neuro-psiquiatria》2005,63(1):160-162
We report a case of a 26-year-old man who presented a lower motor neuron syndrome due to hyperparathyroidism. Electromyography showed neurogenic features with normal nerve conduction studies. Hypercalcemia led to the discovery of a primary hyperparathyroidism with gland hyperplasia. Following parathyroid surgery there was recovery of the neurological symptoms. 相似文献
99.
The authors investigated obsessive-compulsive behavior, obsessive-compulsive disorder (OCD), and attention deficit and hyperactivity disorder (ADHD) in 50 healthy subjects, 50 patients with rheumatic fever without chorea, and 56 patients with Sydenham chorea. Obsessive-compulsive behavior, OCD, and ADHD were more frequent in the Sydenham chorea group (19%, 23.2%, 30.4%) than in the healthy subjects (11%, 4%, 8%) and in the rheumatic fever without chorea group (14%, 6%, 8%). ADHD was more common in persistent Sydenham chorea. 相似文献
100.
Ki-67, Bcl-2 and p53 expression in endometrial polyps and in the normal endometrium during the menstrual cycle 总被引:3,自引:0,他引:3
Maia H Maltez A Studart E Athayde C Coutinho EM 《BJOG : an international journal of obstetrics and gynaecology》2004,111(11):1242-1247
OBJECTIVE: To determine the presence of proteins related to proliferation (Ki-67) and apoptosis (Bcl-2, p53) in endometrial polyps and normal endometrium during the menstrual cycle. DESIGN: Retrospective study using paraffin embedded tissue. SETTING: Hospital affiliated to the university. POPULATION: Premenopausal patients with endometrial polyps. METHODS: Seventy-eight premenopausal patients in different phases of the menstrual cycle were submitted to polypectomy using the Bettocchi hysteroscope. Immunohistochemistry was used to detect the expression of these proteins in endometrial polyps. One hundred and eighteen normal endometrial biopsies were used as controls. MAIN OUTCOME MEASURES: Detection of Bcl-2 and Ki-67 expression by immunohistochemistry. RESULTS: In endometrial polyps, Ki-67, p53 and Bcl-2 expression was detected with more frequency during the proliferative than during the luteal phase of the cycle. Similar findings were observed in the normal endometrium. CONCLUSION: Endometrial polyps undergo cyclic changes in the expression of their proteins related to proliferation and apoptosis during the menstrual cycle, similar to those of the cycling endometrium. 相似文献