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排序方式: 共有3421条查询结果,搜索用时 31 毫秒
31.
Alfredo Vittoria Tiziana Cocca Elena La Mura Aldo Cecio 《Anatomical record (Hoboken, N.J. : 2007)》1992,233(1):18-24
The aim of this study is to describe the presence of neuroendocrine (NE) cells (paraneurons), producing biogenic amines and/or peptidergic hormones, in the female urethra of cattle, sheep, pigs, and horses, by means of histochemical and double labeling immunofluorescent techniques. 5-Hydroxytryptamine-, chromogranin A-, cholecystokinin- and somatostatin-containing NE cells are present in the urethral epithelium of all the species studied, with the unique exception of the lack of somatostatin cells in the horse. Paraneurons containing 5-hydroxytryptamine colocalized with chromogranin A or cholecytokinin were also found in all subjects. Such active substances are hypothesized to play a role in the contraction of the urethral musculature, emission of urogenital fluids, and inhibition of endocrine and exocrine secretions. © 1992 Wiley-Liss, Inc. 相似文献
32.
We report the case of a 43 year-old man, smoker, who used to live in Africa, consulting for a chronic ulcer of the mobile tongue. An initial biopsy did not show any carcinoma. A second biopsy highlighted an inflammation with numerous tuberculoid granulomas. However, the Ziehl-Neelsen stain was negative. Histoplasmosis of the tongue was then suspected as some round structures looking like yeasts and stained by the Gomori Grocott method were seen within the cytoplasm of giant cells. However, immunohistochemistry using anti-Histoplasma antibodies was negative. Polymerase chain reaction (PCR) assay performed on deparaffinized sections allowed the diagnosis of infection by Mycobacterium tuberculosis. A third biopsy confirmed the diagnosis of tuberculosis by showing some exceptional acid-fast bacilli. Culture was negative. Tuberculosis of the tongue is a very rare condition with different differential diagnosis including carcinoma in smoker population or histoplasmosis in endemic area. 相似文献
33.
34.
Heterogeneous pattern of chromosomal breakpoints involving the MYC locus in multiple myeloma 总被引:2,自引:0,他引:2
Fabris S Storlazzi CT Baldini L Nobili L Lombardi L Maiolo AT Rocchi M Neri A 《Genes, chromosomes & cancer》2003,37(3):261-269
Chromosomal rearrangements of the MYC locus, which often involve the IG loci, are recurrent events in multiple myeloma (MM) and plasma cell leukemia (PCL). We used dual-color fluorescence in situ hybridization (FISH) to characterize the breakpoint locations of chromosomal translocations/rearrangements involving the MYC locus at 8q24 found in a panel of 14 MM cell lines and 70 primary tumors (66 MM and 4 PCL). MYC locus alterations were observed in 21 cases: MYC/IG (mainly IGH@) fusions in 11 cell lines and three patients (2 MM and 1 PCL), and extra signals and/or abnormal MYC localizations in seven patients (5 MM and 2 PCL). Fourteen of these cases were investigated by FISH analyses by use of a panel of BAC clones covering about 6 Mb encompassing the MYC locus. The breakpoints were localized in a region 100-250 kb centromeric to MYC in four cases, a region 500-800 kb telomeric to the gene in four cases, and regions > or = 2 Mb centromeric or telomeric to MYC in five cases. Two different breakpoints were detected in the KMS-18 cell line, whereas the insertion of a MYC allele was found in a complex t(16;22) chromosomal translocation in the RPMI8226 cell line. Our data document a relatively high dispersion of 8q24 breakpoints in MM. 相似文献
35.
A study of the possible molecular mechanisms of action by which the isomers and metabolites of fenfluramine increase serotonin transmission, leading to anorectic activity, is presented. The actual brain levels of fenfluramine and norfenfluramine isomers after administration of equi-anorectic doses to rats are compared with their potencies in affecting serotonergic mechanisms in vitro. Isomers and metabolites of fenfluramine can have the same pharmacological action by influencing serotonin uptake, release and binding in a quantitatively different manner. 相似文献
36.
Marcello Dallio Mario Romeo Antonietta Gerarda Gravina Mario Masarone Tiziana Larussa Ludovico Abenavoli Marcello Persico Carmelina Loguercio Alessandro Federico 《Nutrients》2021,13(5)
Metabolic- (dysfunction) associated fatty liver disease (MAFLD) represents the predominant hepatopathy and one of the most important systemic, metabolic-related disorders all over the world associated with severe medical and socio-economic repercussions due to its growing prevalence, clinical course (steatohepatitis and/or hepatocellular-carcinoma), and related extra-hepatic comorbidities. To date, no specific medications for the treatment of this condition exist, and the most valid recommendation for patients remains lifestyle change. MAFLD has been associated with metabolic syndrome; its development and progression are widely influenced by the interplay between genetic, environmental, and nutritional factors. Nutrigenetics and nutrigenomics findings suggest nutrition’s capability, by acting on the individual genetic background and modifying the specific epigenetic expression as well, to influence patients’ clinical outcome. Besides, immunity response is emerging as pivotal in this multifactorial scenario, suggesting the interaction between diet, genetics, and immunity as another tangled network that needs to be explored. The present review describes the genetic background contribution to MAFLD onset and worsening, its possibility to be influenced by nutritional habits, and the interplay between nutrients and immunity as one of the most promising research fields of the future in this context. 相似文献
37.
Carola Buscemi Yvelise Ferro Roberta Pujia Elisa Mazza Giada Boragina Angela Sciacqua Salvatore Piro Arturo Pujia Giorgio Sesti Silvio Buscemi Tiziana Montalcini 《Nutrients》2021,13(6)
Elderly women exhibit a high risk of type 2 diabetes (T2D), but no definitive data exist about the possible role of postmenopausal increases in visceral adiposity, the loss of lean body mass, or decreases in the sum of the lean mass of arms and legs (appendicular skeletal muscle mass (ASMM)). This retrospective, longitudinal study investigated whether body composition (bioelectrical impedance analysis) predicted the development of impaired fasting glucose (IFG) or T2D in a cohort of 159 elderly women (age: 71 ± 5 years, follow-up: 94 months) from southern Italy (Clinical Nutrition and Geriatric Units of the “Mater Domini” University Hospital in Catanzaro, Calabria region, and the “P. Giaccone ”University Hospital in Palermo, Sicily region). Sarcopenia was defined in a subgroup of 128 women according to the EWGSOP criteria as the presence of low muscle strength (handgrip strength <16 kg) plus low muscle mass (reported as appendicular skeletal muscle mass <15 kg). Participants with a low ASMM had a higher IFG/T2D incidence than those with a normal ASMM (17% vs. 6%, p-adjusted = 0.044); this finding was independent of BMI, fat mass, waist circumference, and habitual fat intake (OR = 3.81, p = 0.034). A higher incidence of IFG/T2D was observed in the subgroup with sarcopenia than those without sarcopenia (33% vs. 7%, p-adjusted = 0.005) independent of BMI and fat mass (OR = 6.75, p = 0.007). In conclusion, this study demonstrates that elderly women with low ASMM had a higher probability of developing IFG/T2D. Further studies are needed to confirm these results in men and in other age groups. 相似文献
38.
Vercellini Paolo; Parazzini Fabio; Oldani Sabina; Panazza Stefania; Bramante Tiziana; Crosignani Pier Giorgio 《Human reproduction (Oxford, England)》1995,10(5):1160-1162
To evaluate the prevalence and risk factors for adenomyosis,the clinical records of consecutive women undergoing hysterectomyduring a 3 year period were retrieved. Data were collected onindication for the intervention, general sociodemographic characteristicsof the patients, age at menarche, parity, abortions, and menopausalstatus at surgery. Adenomyosis was diagnosed in 332 of the 1334cases (24.9%). The condition was present in 146 of the 627 patients(23.3%) with fibroids and menorrhagia, 68 of the 265 (25.7%)with prolapse, 21 of the 98 (21.4%) with ovarian cysts, 19 ofthe 100 (19%) with cervical cancer, 31 of the 110 (28.2%) withendometrial cancer, 16 of the 57 (28.1%) with ovarian cancer,and 19 of the 77 (24.7%) with miscellaneous indications. Thesedifferences were not statistically significant (x26 = 11.14).In comparison with nulliparous women, the odds ratio was 1.3and 1.5 respectively in women with one and two births (x21 trend= 5.76, P < 0.05). No relationship was found between ageat surgery, age at menarche, indications for surgery, menopausalstatus at intervention, and presence of endometriosis. Our findingsdo not support the notion that adenomyosis is more frequentlyrelated to particular clinical conditions, and suggest thatparity may be associated with an increased frequency of adenomyosis. 相似文献
39.
Elisabetta Ciani Tiziana Guarnieri Antonio Contestabile 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1994,98(3):421-430
The excitotoxins kainic acid and N-methyl d-aspartate (NMDA) were unilaterally injected in the rat striatum. Kainic acid injections resulted in a widespread pattern of Fos protein induction, mainly involving cortical olfactory structures and hippocampus. Immunoreactive cells were observed in large number 2–24 h after injection and had almost completely disappeared by 48 h. NMDA injections elicited a shorter (2–8 h) expression of Fos protein, involving a lower number of cells in cortical olfactory structures, a much larger number of cells in the other cortical regions, and not involving the hippocampus at all. Characteristically none of the two excitotoxins stimulated Fos expression from striatal neurons, even in the close vicinity of the needle tract. In addition to striatal lesions almost equivalent in size, the two excitotoxins caused distant lesions of different extension: kainic acid resulted in extensive neuronal degeneration in the olfactory-entorhinal cortices and among pyramidal neurons of the hippocampus; NMDA caused a less widespread neurodegeneration, restricted to the olfactory cortex. Administration of the competitive NMDA antagonist CGP 39551 largely prevented the distant, but not the local, neuropathological changes caused by intrastriatal kainic acid or NMDA. The expression of Fos protein, however, was partially prevented only in NMDA cases. The present results show a good relationship between the spreading of circuit overexcitation caused by the two excitotoxins and the regional and temporal patterns of Fos expression. The relationship between Fos expression and neuropathological condition remains, however, elusive. 相似文献
40.
Infant Manipulative Actions upon Customary and Uncustomary Objects in Independent and Joint Activity
Eight 12 month-olds acting on objects were observed in two sessions: 1) the objects were home objects; 2) they were brought by the observer as new exemplars of previous toys. Infants were observed manipulating objects independently and with their mothers. Type and cognitive level of infant's actions were coded. Conventional actions were more frequent in joint than independent activity. In independent activity, conventional actions were more frequent with customary objects. High cognitive level was more frequent with customary objects. Acting with an adult is the major influential factor in promoting conventional usage of an object. However, acting on customary objects influences both conventional usage and organization of the actions. Notion of joint activity as a social practice rather than interactional event can be useful in accounting for this influence. 相似文献