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排序方式: 共有10000条查询结果,搜索用时 437 毫秒
91.
92.
Ch. Madl G. Grimm R. Mallek B. Schneeweiß W. Druml A. N. Laggner K. Lenz 《Intensive care medicine》1992,18(4):245-246
In the presence of ascites ultrasound is not appropriate to distinguish between gallbladder perforation and acute acalculous cholecystitis. However, the correct and early diagnosis of gallbladder perforation is important for the treatment and prognosis. We report 4 critically ill patients with ascites. All patients had evidence of gallbladder perforation by ultrasound and underwent cholecystectomy: 2 patients had gallbladder perforation, but 2 had acalculous cholecystitis without perforation. markedly elevated serum alkaline phosphatase was the only discriminating finding indicating gallbladder perforation. 相似文献
93.
94.
Nicole Y. L. Oei Bernet M. Elzinga Oliver T. Wolf Michiel B. de Ruiter Jessica S. Damoiseaux Joost P. A. Kuijer Dick J. Veltman Philip Scheltens Serge A. R. B. Rombouts 《Brain imaging and behavior》2007,1(1-2):31-41
Glucocorticoids (GCs, cortisol in human) are associated with impairments in declarative memory retrieval. Brain regions hypothesized
to mediate these effects are the hippocampus and prefrontal cortex (PFC). Our aim was to use fMRI in localizing the effects
of GCs during declarative memory retrieval. Therefore, we tested memory retrieval in 21 young healthy males in a randomized
placebo-controlled crossover design. Participants encoded word lists containing neutral and emotional words 1 h prior to ingestion
of 20 mg hydrocortisone. Memory retrieval was tested using an old/new recognition paradigm in a rapid event-related design.
It was found that hydrocortisone decreased brain activity in both the hippocampus and PFC during successful retrieval of neutral
words. These observations are consistent with previous animal and human studies suggesting that glucocorticoids modulate both
hippocampal and prefrontal brain regions that are crucially involved in memory processing.
Electronic Supplementary Material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
95.
Gysèle S Bleumink Anna F C Schut Miriam C J M Sturkenboom Jaap W Deckers Cornelia M van Duijn Bruno H Ch Stricker 《Genetics in medicine》2004,6(6):465-474
Heart failure is a complex clinical syndrome. There is evidence for a genetic contribution to the pathophysiology of heart failure. Considering the fundamental role of neurohormonal factors in the pathophysiology and progression of cardiac dysfunction and hypertrophy, variants of genes involved in this system are logical candidate genes in heart failure. In this report, genetic polymorphisms of the major neurohormonal systems in heart failure will be discussed. Studies on polymorphisms of the renin-angiotensin-aldosterone system (RAAS), adrenergic receptor polymorphisms, endothelin (receptor) polymorphisms, and a group of miscellaneous polymorphisms that may be involved in the development or phenotypic expression of heart failure will be reviewed. Research on left ventricular hypertrophy is also included. The majority of genetic association studies focused on the ACE I/D polymorphism. Initial genetic associations have often been difficult to replicate, mainly due to problems in study design and lack of power. Promising results have been obtained with genetic polymorphisms of the RAAS and sympathetic system. Considering the evidence so far, a modifying role for these polymorphisms seems more likely than a role of these variants as susceptibility genes. Besides the need for larger studies to examine the effects of single nucleotide polymorphisms and haplotypes, future studies also need to focus on the complexity of these systems and study gene-gene interactions and gene-environment interactions. 相似文献
96.
Dopamine neurons projecting to the medial prefrontal cortex possess release-modulating autoreceptors 总被引:6,自引:0,他引:6
The ability of dopamine (DA) agonists and antagonists to modulate the K+-evoked overflow of radioactivity from superfused slices of prefrontal cortex of the rat, preincubated with [3H]DA in the presence of 1 microM desipramine, was examined. Apomorphine and the putative autoreceptor-selective DA agonist EMD 23 448 inhibited the K+-evoked overflow of radioactivity, while the DA antagonist sulpiride enhanced the evoked overflow in a dose-dependent and stereoselective manner. The latter effect was partially reversed by EMD 23 448. More than 95% of the radioactivity retained by the slices chromatographed with DA, while deaminated metabolites represented the majority of both the basal efflux (84% metabolites, 4-5% DA) and evoked overflow (84% metabolites, 14% DA) of radioactivity. These findings indicate that mesoprefrontal DA neurons possess release-modulating nerve terminal autoreceptors. Previous studies have shown that these neurons lack synthesis-modulating autoreceptors. Thus, autoreceptors on prefrontal DA terminals appear to be coupled to regulation of the release but not the synthesis of DA. 相似文献
97.
A case-control study was conducted to test the hypothesis that chronic ingestion of trihalomethanes (THMs), occurring as chlorination byproducts in drinking water, carries a risk of colon cancer. Lifetime residential and water source histories and information on water-drinking habits, diet, sociodemographics, medical and occupation histories, lifestyle and other factors were obtained by questionnaire from a statewide sample of newly-diagnosed colon cancer cases (N = 347), controls with cancer of other sites (N = 639) and general population controls (N = 611). Since no data on past THM levels exists, it was necessary to devise a scheme to generate THM estimates for all Wisconsin water sources. For this, a statistical model based on quantitative THM measures and routinely-recorded data taken at 81 municipal water facilities was used in conjunction with individual residential histories to estimate lifetime and period-specific THM exposure for each case and control. Logistic regression was used to estimate odds ratios adjusted for age, sex and urban living, for colon cancer and THM exposure. The study results indicate that THM in Wisconsin drinking water does not pose a significant colon cancer risk. Odds ratios for exposure to the middle and highest category of lifetime cumulative THM were 1.05 (95% Cl = 0.66-1.68) and 0.93(95%Cl = 0.55-1.57) respectively, relative to the cancer control group, and 1.10 (95%Cl = 0.68-1.78) and 0.73 (95% Cl = 0.44-1.21) respectively, relative to the general population controls.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
98.
T Vera Castillo T Sánchez Santana M Castro Chávez E Pozo Madera V P Díaz Narváez B Fernández 《Revista cubana de enfermería》1986,2(3):217-231
A survey was conducted in early 1985 among 366 new mothers at 3 hospitals in Pinar del Rio, Cuba, to assess their level of health information regarding the care of newborns. The 11 study variables included breastfeeding, weaning, bathing the newborn, care of clothing and equipment for the baby, well baby visits, vaccination, accidents and safety, parent-child relations, sex education, and the puerperium. The level of information on these topics was generally low and was adequate only for breastfeeding. The information deficit was not related to urban or rural residence, parity, or educational level. The lack of knowledge of new mothers was attributed to the lack of motivation of health personnel at all levels to provide health education, inadequate use of existing information channels, and a lack of emphasis on health education within the general educational system. 相似文献
99.
Bone remodeling during the development of osteoporosis in paraplegia 总被引:11,自引:0,他引:11
Professeur A. Chantraine B. Nusgens Ch. M. Lapiere 《Calcified tissue international》1986,38(6):323-327
Summary Osteoporosis developing during the first weeks after the onset of traumatic paraplegia was studied with cortical and cancellous
samples of iliac crest and tibia of 14 patients, and compared to normals. We used a procedure of bone particle fractionation
(according to degree of mineralization) that allowed us to establish a profile reflecting the metabolic remodeling of bone
and to analyze the organic matrix of the newly synthesized tissue. In paraplegics, we observed a large increase in the proportion
of little calcified bone in the cortical as well as in the cancellous bone. Based on amino acid analyses, we found a decreased
number of hydroxyproline residues in the newly synthesized organic matrix from paraplegia bone resulting either from an alteration
of the prolyl hydroxylation or from the presence of an excess of noncollagen polypeptides. These results, together with previously
published data reporting increased urinary hydroxylproline and calcium kinetic parameters, suggest an enhanced rate of skeletal
remodeling in acute paraplegia. When investigated 2 years after injury, the patterns of distribution approach that of normal
subjects. 相似文献
100.