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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
In the present study, chlorogenic acid (CGA) isolated from Anthocephalus cadamba was screened for hepatoprotective activity by in vitro and in vivo assay methods using carbon tetrachloride (CCl4) as a model of liver injury. Intraperitoneal administration of CGA to mice at a dose of 100 mg/kg body weight for 8 days caused significant reversal in lipid peroxidation, enzymatic leakage, cytochrome P450 (Cyt P450) inactivation and produced enhancement of cellular antioxidant defence in CCl4-intoxicated mice, revealing that the antioxidative action of CGA is responsible for its liver protective activity. CGA exhibited a better therapeutic protective action than silymarin (SM), in CCl4-administered mice. 相似文献
992.
Calcitonin gene-related peptide (CGRP) causes vasorelaxation in rat aorta involving endothelium/nitric oxide (NO)-dependent elevations of both cAMP and cGMP levels. When endothelium is removed, preincubation with exogenous NO uncovers and potentiates direct (endothelium-independent) cAMP elevations and vasorelaxations caused by CGRP. This enhancing effect of NO potentially involves elevation of cGMP and inhibition of Type III (cGMPinhibitable) phosphodiesterase, causing accumulation of cAMP. However, NO may have other actions. The aim of the present study was to determine if brain natriuretic peptide (BNP), which elevates cGMP levels independent of NO, could enhance cAMP accumulations and vasorelaxations induced by CGRP in rat aortic rings denuded of endothelium. When added separately, neither CGRP (100 nM) nor BNP (10 nM) altered cAMP levels. When added in combination, CGRP (100 nM) and BNP (10 nM) significantly elevated cAMP levels (from control of 0.95 ± 0.08 to 1.53 ± 0.09 pmol/mg protein) at 2 min. BNP (10 nM) elevated cGMP levels 10-fold at 2 min and this response was not altered by co-administration of CGRP (100 nM).Pretreatment with BNP at concentrations as low as 1 nM in endothelium-denuded aortic rings greatly enhanced the direct vasorelaxant effects of CGRP (100 nM) (from control of 0% to 57.6 ± 6.8% relaxation of phenylephrineprecontractions). Our findings indicate that BNP enhances direct (endothelium-independent) cAMP elevations and vasorelaxations caused by CGRP in rat aorta, thus supporting the concept that cGMP inhibits cAMP metabolism and enhances CGRP-induced responses in aortic smooth muscle cells. 相似文献
993.
Robert K.P Chow MD Vincent C Ho MD FRCPC 《Journal of the American Academy of Dermatology》1996,34(6):1047-1060
Critical to the proper management of pyoderma gangrenosum are correct diagnosis, identification and treatment of any underlying disorder, and the proper choice of topical and systemic therapy. Many agents are available for the treatment of pyoderma gangrenosum. We review the current therapeutic options, their efficacy and side effects, and we offer some guidelines for their proper selection. 相似文献
994.
This paper describes a complex set of patient and nursing data from 83 psychiatric wards. It explains how the data were collected and organized into a meaningful format using a quality league-table. The patient and nursing characteristics of high quality psychiatric wards ranking above the 74th percentile and the characteristics of low quality wards falling below the 26th percentile are compared and examined in detail. Startling similarities and differences in patient activity, nursing activity, and nursing quality in high and low quality wards are highlighted. Finally, some implications of the findings for nursing practice, management, and education are considered. 相似文献
995.
P. D. Tsitsopoulos C. A. Tsonidis K. A. Nanasis K. D. Tsoleka G. N. Tavridis 《Acta neurochirurgica》1995,135(3-4):198-200
Summary This report deals with a case of rhabdomyosarcoma in the upper thoracic spine. It is of particular interest, not only for the rarity of type and location of this tumour, but for its clinical course, which presented fluctuations of neurological status, included an acute demonstration of complete paraplegia followed by full recovery after conservative treatment, and gradual relapsing of neurological deficit, one year later. 相似文献
996.
Dr. J. Tajti MD PhD ; Dr. K. Sas MD ; Dr. D. Szok MD ; Dr. E. Vörös MD ; Dr. L. Vécsei MD DSc 《Headache》1996,36(4):259-260
We report on a patient with clusterlike headache and multiple brain metastases of lung cancer. Initially, cluster headache was suggested clinically by characteristic symptoms without any focal central nervous system signs. However, magnetic resonance imaging demonstrated multiple brain metastases. It is possible that tumor necrosis factor may have played a role in initiating the clusterlike headache. 相似文献
997.
M. Vrethem B. Lindvall S. Kihlstrand E. Bckman T. Brismar P. Fredman K.G. Henriksson 《European journal of neurology》1996,3(2):156-159
We report improvement in muscle strength in a patient with multifocal motor neuropathy (MMN) when given high-dose intravenous immunoglobin (i.v.-Ig) treatment. The patient had asymmetrical limb weakness, atrophy and absent or weak reflexes, but no sensory disturbances. Neurography showed multiple conduction blocks in peripheral motor nerves but no sensory nerve abnormalities. Serum and anti-GM1 antibodies were not found, however, the patient had serum antibodies against the glycolipid LK1, an epitope found both in glycolipid and also in some glycoproteins in peripheral nerve myelin. Muscle strength improved 5 days after i.v.-Ig therapy, and lasted about 10 weeks. Repeated courses of treatment resulted in similar improvement. This is, to our knowledge, the first patient reported with MMN found to have antibodies against the glycolipid LK1. 相似文献
998.
Retrospective review of the abdominal ultrasound (US) examination of 274 children studied for hypertrophic pyloric stenosis (HPS) was undertaken to determine if there is an increased incidence of renal disease as previously reported. Five major abnormalities were detected in the 126 children with HPS. Three lesions were newly diagnosed and two had been diagnosed previously. Five children had abnormalities classified as minor or normal variants. Renal abnormalities were found in six of the 148 children who did not HPS. Only three of these were newly diagnosed and medically important. Eight children without HPS had minor abnormalities or normal variants of the kidneys. Newly diagnosed medically important renal lesions were present in 2.4% of children screened for HPS. The incidence of the finding was the similar in children with and without HPS.Paper presented at 1992 RSNA meeting 相似文献
999.
U Burchardt K Winkler M Klagge D Balschun A Barth 《Zeitschrift für klinische Chemie und klinische Biochemie》1988,26(8):491-496
The temporal courses of dipeptidyl peptidase IV gamma-glutamyltransferase and alanine aminopeptidase were followed over 70 days in the morning urine of 15 healthy persons. Subsequent to basic statistical analysis a two-step procedure was performed, including spectral analysis and the fit of a cosine function by non-linear regression. The excretion of the 3 enzymes followed an infradian biorhythm with a mean period length of 10.04 for dipeptidyl peptidase IV, 13.34 for gamma-glutamyltransferase and 10.17 for alanine aminopeptidase. In addition to the basic rhythmic process described by the fitted cosine functions, in most of the enzyme patterns steap peaks of very high excretory activity appeared which was verified in repeated measurements. These infradian biorhythms with changes in the range of 100% and more, as well as their interindividual variations, have to be considered in assessing the excretion of enzymes. 相似文献
1000.