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排序方式: 共有10000条查询结果,搜索用时 296 毫秒
71.
Ciasca SM Alves HL Guimarães IE Terra AP Moura-Ribeiro MV Camargo EE Etchebehere ES Santos Ade O 《Arquivos de neuro-psiquiatria》1999,57(4):1036-1040
Moyamoya is a chronic progressive cerebrovascular disease with characteristic angiographic findings and a clinical picture with episodes of transient ischemic attacks, headache, seizures, hemiparesis, which may resolve after surgical treatment. We describe the case of a girl with the typical findings of the disease, comparing them before and after surgery with the use of neuropsychological tests, neurological examination and laboratory tests. 相似文献
72.
Previous studies have shown that several immune functions were improved in mice after the ingestion of a thioproline (thiazolidine-4-carboxylic acid) enriched diet. In the present work, we have studied the in vitro effects of several concentrations of this thiol compound (0.1, 0.5, 1, 2.5 and 5 mM) on the most relevant functions of three pivotal immune cells, namely, macrophages, lymphocytes, and natural killer (NK) cells from BALB/c mice. The results show that thioproline stimulates the phagocytic process of macrophages, increasing the mobility directed to the inflammatory focus (chemotaxis) and the phagocytosis of inert particles. It increases the adherence and the chemotaxis capacities of lymphocytes, their proliferative activity and favours the natural cytotoxic activity that could improve the capacity to destroy malignant cells. Thioproline concentrations of 0.5 and 1 mM were the most effective regarding the different functions analysed. These results suggest that the improvement of immune functions, observed in previous work, after thioproline-enriched diet ingestion is due to a direct action of this thiol compound on immune cells. 相似文献
73.
Root bark of West African tree DIOSPYROS BATOCANA H IERN, Ebenaceae, was examined. On the basis of chromatographic and spectral analysis it was shown to contain the naphtaquinones 7-methyljuglone, 2-methylnaphthazarin, biramentaceone, rotundiquinone, mamegakinone, diospyrin, diosquinone, isodiospyrin and batocanone. This last compound proved to be the (-)-enantiomer of isodiospyrin-2', 3'-epoxide. The probable existence of beta-dihydrodiospyrin, of a batocanone isomer and of an isodiospyrin diepoxide in this material is mentioned. The partial synthesis of two isomeric isodiospyrin di-epoxides is described. 相似文献
74.
From 1987 to 1989, a hospital-based case-control study of cancer of the tongue was conducted in Montevideo, Uruguay, as part of a large study to investigate a number of risk factors for cancer of the oral cavity, pharynx, and larynx. The study involved interviews with 57 cases and 353 controls and was restricted to men. Relative risks (RR) associated with tobacco smoking, alcohol drinking, and selected dietary items were obtained by unconditional logistic-regression analysis. Users of black tobacco had a RR fourfold higher than users of blond tobacco, and heavy drinkers of alcohol had a RR of 11.6. Infrequent consumption of vegetables was associated with a significant RR of 5.3, and heavy drinkers of the local infusion "mate" had a RR of 2.5. It was concluded that black tobacco smoking and alcohol drinking were the strongest risk factors for cancer of the tongue in Uruguay. Their effects combine according to a multiplicative model. Also, infrequent vegetable intake and mate ingestion contribute to the risk of cancer of the tongue. 相似文献
75.
The in vitro effect of Praziquantel (PZQ) onTaenia solium cysticerci was analyzed. The oxygen consumption rate of the parasites was inhibited and the release of proteins was enhanced, but no statistically significant differences were found between the control group and the experimental groups. The drug had a significant, dose-dependent negative effect on the evagination ability of the larvae; 50% effect was seen at concentrations of between 10–9 and 10–8
M PZQ. The drug also induced morphological disturbances in the tegument of the worm and of the bladder wall. Finally, a very drastic effect was the induction of spastic paralysis in evaginated cysticerci at high drug doses and of flaccid paralysis at lower PZQ concentrations. The dose inducing these effects was various orders of magnitude lower than that inhibiting the evagination ability of intact cysts. Moreover, the latter effect was reversible after had been washed out the drug and the parasites had been cultured. We suggest that PZQ alters the Ca2+ flux inT. solium as it does in other helminths. Furthermore, we corroborated the protective role of the bladder for the invaginated worm. Finally, we think that in vivo the drug must act synergistically with the immune system components so as to eliminate the parasite. 相似文献
76.
77.
Since exogenous hemin has been shown to exert a variety of stimulatory effects on erythroid cells, including the augmentation of hemoglobin synthesis, we determined its effect on early stages of erythroid development by employing clonal cells assays. The addition of hemin at a concentration of 2 X 10(-4) M to cultures of normal murine marrow substantially increased the observed number of primitive BFU-E, which was in contrast to its lack of an effect on more mature erythroid colony-forming cells. This cell-specific enhancement of primitive BFU-E resulted in marrow frequencies equivalent to or exceeding those reported in the presence of "burst-promoting activity." In the presence of hemin, the number of BFU-E was also observed to be linearly related to the number of cells plated at very low plating densities, and the cell titration curve was observed to extrapolate to the origin. The evidence suggests that hemin may be a primary growth regulator of early developmental stages of erythroid progenitor cells. 相似文献
78.
Ferri-De-Barros JE Veiga JC Priante AV Cardoso CA Alves FL Ferri-De-Barros M Turrini RM Oliveira SD Fontana Junior S 《Arquivos de neuro-psiquiatria》2000,58(1):128-135
INTRODUCTION: Knowledge accumulation is overfilling the thematic content of medical graduation. Medical Schools must be alert to define a minimal content related with the most frequent disturbs. We intent to suggest topics for the minimal content, to the program of Neurology in medical graduation. METHOD: 1. To identify the places where young doctors are working outside the School Hospital (SH): we analysed the answers of the letters sent to 6415 resident - doctors (RD) in S?o Paulo's State and we made personal interview with 201 RD. 2. To verify the most frequent neuropsychiatric disturbs (ND) in the population: we made the analysis of the patient's diagnostic records in emergency room of three institutions: Municipal of Taubaté-SP, Municipal of S?o José dos Campos-SP and Faculty of Medicine of S?o Paulo Santa Casa de Misericórdia. RESULTS: 1. The RD are young and, outside the SH, they work in other emergency services. 2. The most frequent diagnosis in institutions were listed: alcoholism, cerebrovascular disease, coma, cranial trauma, dementia, dizziness, epilepsy, facial paralysis, faint, headache, hemiplegia or paraplegia, meningitis, others paralysis, periferical neuropathy and psychiatric disorders. CONCLUSIONS: Those diagnostics most frequent are relevant topics of the programmatic content to the program of Neurology in medical graduation. 相似文献
79.
Fernanda B Nunes Cássio M Graziottin José Carlos F Alves Filho Adroaldo Lunardelli Melissa G S Pires Paulo H W?chter Jarbas R De Oliveira 《Pharmacological research》2003,47(1):35-41
Tissue lesion mechanisms provoked by sepsis include the infectious process, inflammation, and cellular energy deficit. We chose to test fructose-1,6-bisphosphate (FBP) because of its possible anti-inflammatory and antimicrobial actions. Wistar rats were used and divided into three experimental groups: a control group (n=10), in which a capsule was introduced into the peritoneum of the animals; a septic group (n=10), in which a capsule containing non-sterile fecal matter was introduced together with Escherichia coli (1.5 x 10(9)CFU); and a septic group treated with FBP 500 mg/kg (n=10). The blood cell tests revealed that levels of leukocytes increased significantly in the septic group when compared to both the septic group treated with FBP and the control group. The blood cultures were 100% positive in both the septic group and the septic group treated with bisphosphorylated sugar. The antibiogram only revealed an inhibitory halo in the case of the antibiotic ampicillin, there was no such indication for FBP. The anti-inflammatory power of FBP remained at 60% for 5 h in the rats that received the carrageenan injection. What is more, the sugar reduced the levels of ionic calcium in relation to the control group. This data proves the validity of using FBP in the treatment of sepsis, possibly due to its anti-inflammatory rather than antimicrobial action. 相似文献
80.
Hirsch J Ruge MI Kim KH Correa DD Victor JD Relkin NR Labar DR Krol G Bilsky MH Souweidane MM DeAngelis LM Gutin PH 《Neurosurgery》2000,47(3):711-21; discussion 721-2
OBJECTIVE: To evaluate an integrated battery of preoperative functional magnetic resonance imaging (fMRI) tasks developed to identify cortical areas associated with tactile, motor, language, and visual functions. METHODS: Sensitivity of each task was determined by the probability that a targeted region was activated for both healthy volunteers (n = 63) and surgical patients with lesions in these critical areas (n = 125). Accuracy of each task was determined by the correspondence between the fMRI maps and intraoperative electrophysiological measurements, including somatosensory evoked potentials (n = 16), direct cortical stimulation (n = 9), and language mapping (n = 5), and by preoperative Wada tests (n = 13) and visual field examinations (n = 6). RESULTS: For healthy volunteers, the overall sensitivity was 100% for identification of the central sulcus, visual cortex, and putative Wernicke's area, and 93% for the putative Broca's area (dominant hemisphere). For patients with tumors affecting these regions of interest, task sensitivity was 97% for identification of the central sulcus, 100% for the visual cortex, 91% for the putative Wernicke's area, and 77% for the putative Broca's area. These sensitivities were enhanced by the use of multiple tasks to target related functions. Concordance of the fMRI maps and intraoperative electrophysiological measurements was observed whenever both techniques yielded maps and Wada and visual field examinations were consistent with fMRI results. CONCLUSION: This integrated fMRI task battery offers standardized and noninvasive preoperative maps of multiple critical functions to facilitate assessment of surgical risk, planning of surgical routes, and direction of conventional, intraoperative electrophysiological procedures. Thus, a greater range of structural and functional relationships is brought to bear in the service of optimal outcomes for neurosurgery. 相似文献