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951.
Sophie?L.?WoolstonEmail author Shireesha?Dhanireddy Jeanne?Marrazzo 《Current infectious disease reports》2016,18(11):36
While ocular syphilis is not a new phenomenon, recent increased rates of new diagnoses, especially in human immunodeficiency virus (HIV)-infected persons and men who have sex with men, have sparked a new interest in an old disease. This article will review the clinical presentation, diagnosis, and treatment of ocular syphilis, and provide guidance on management. 相似文献
952.
We report on a carrier of human T-lymphotropic virus type 1 (HTLV-1) who developed mixed connective tissue disease (MCTD). This patient suddenly manifested clinical symptoms and interstitial pneumonia ascribable to MCTD following long-term infection with HTLV-1. After initiation of oral prednisolone all manifestations quickly improved in parallel with a decrease in inflammatory reactions. In this patient HTLV-1 infection might have played an important role in the pathogenesis of MCTD. Since HTLV-1 can cause adult T-cell leukemia and HTLV-1-associated myelopathy, and also collagen diseases including MCTD, careful observation is necessary even in a carrier, particularly when autoantibodies are detectable in serum. 相似文献
953.
D'Annibale A Morpurgo E Fiscon V Trevisan P Sovernigo G Orsini C Guidolin D 《Diseases of the colon and rectum》2004,47(12):2162-2168
PURPOSE In the last ten years, several robotic systems have been developed to overcome the loss of the three-dimensional view and dexterity characteristic of laparoscopic surgery. The aim of this study was to compare the traditional laparoscopic approach and robotic techniques in the treatment of colorectal diseases.METHODS The study compares a consecutive series of patients treated surgically for colorectal disease from June 2001 to May 2003 with the da Vinci robotic system (Intuitive Surgical®) and a matched number of patients who underwent conventional laparoscopy during the same time interval. The factors analyzed were the time required to prepare the patient and the room, total time of surgery, length of specimens, number of lymph nodes retrieved, blood loss, complications, and postoperative results.RESULTS The study included 106 patients (53 in each group). No differences were observed in total time of surgery (laparoscopic group, 222 ± 77 minutes vs. robotic group, 240 ± 61 minutes), specimen length (laparoscopic group, 29 ± 11 cm vs. robotic group, 27 ± 13 cm), or number of lymph nodes retrieved (laparoscopic group, 16 ± 9 vs. robotic group, 17 ± 10). It took significantly longer to prepare the operating room and patient in the robotic group (24 ± 12 minutes) than in the laparoscopic group (18 ± 7 minutes). There were three conversions to laparotomy in the laparoscopic group; in the robotic group, two cases were converted to laparoscopy and three to hand-assisted laparoscopy. No significant differences were observed between the two groups in terms of recovery of bowel function and postoperative hospital stay.CONCLUSIONS Robot-assisted surgery proved to be as safe and effective as laparoscopic techniques in the treatment of colorectal diseases. Because of its dexterity and three-dimensional view, the da Vinci system was particularly useful in specific stages of the procedure, e.g., takedown of the splenic flexure, dissection of a narrow pelvis, identification of nervous plexus, and handsewn anastomosis. The cost-effectiveness of the procedure still needs to be evaluated. 相似文献
954.
Toubo T Suga N Ohga S Nomura A Onoe Y Takada H Hara T 《International journal of hematology》2004,80(5):458-462
We report a case of successful umbilical cord blood transplantation (CBT) for Epstein-Barr virus (EBV)-associated lymphoproliferative disease (LPD) in a 6-year-old girl. The patient had hemophagocytic syndrome with excessive circulating levels of EBV DNA that was refractory to immunochemotherapy. Multiple hepatosplenic lesions favored the diagnosis of EBV-associated LPD, although the aggressive course precluded the histopathologic diagnosis. Unrelated CB cells mismatched at 1 HLA locus were infused after patient conditioning with 900 mg/m2 etoposide, 2 g/m2 cytarabine, 16 mg/kg busulfan, and 200 mg/kg cyclophosphamide. Complete chimeric status was obtained on day 19 posttransplantation. Drug fever and acute graft-versus-host disease of the skin (grade II) were the major complications. A transient increase of EBV DNA 1 year after CBT indicated a primary EBV infection of the donor cells. The patient is alive with no evidence of disease 27 months after CBT. There has been no previous report of successful CBT for EBV-related LPD/lymphoma. CBT can be a curative treatment for the disease, even if no viral memory has been set in the stem cell source. 相似文献
955.
Giordano R Picu A Broglio F Bonelli L Baldi M Berardelli R Ghigo E Arvat E 《Pituitary》2004,7(4):243-248
Ghrelin, a peptide predominantly produced by the stomach, has been discovered as a natural ligand of the GH Secretagogue receptor
type 1a (GHS-R1a), known as specific for synthetic GHS. Ghrelin has recently attracted considerable interest as a new orexigenic
factor. However, ghrelin exerts pleiotropic actions that are explained by the widespread distribution of ghrelin and GHS-R
expression. Besides strong stimulation of GH secretion, the neuroendocrine ghrelin actions also include significant stimulation
of both lactotroph and corticotroph secretion; all these actions depend on acylation of ghrelin in serine-3 that allows binding
and activation of the GHS-R1a. However, GHS-R subtypes are likely to exist; they also bind unacylated ghrelin that is, in
fact, the most abundant circulating form and exerts some biological actions. Ghrelin secretion is mainly regulated by metabolic
signals, namely inhibited by feeding, glucose and insulin while stimulated by energy restriction. The role of glucocorticoids
on ghrelin synthesis and secretion is still unclear although morning ghrelin levels have been found reduced in some patients
with Cushing's syndrome; this, however, would simply reflect its negative association to body mass. Ghrelin, like synthetic
GHS, stimulates ACTH and cortisol secretion in normal subjects and this effect is generally sensitive to the negative glucocorticoid
feedback. It is remarkable that, despite hypercortisolism, ghrelin as well as synthetic GHS display marked increase in their
stimulatory effect on ACTH and cortisol secretion in patients with Cushing's disease. This is even more intriguing considering
that the GH response to ghrelin and GHS is markedly reduced by glucocorticoid excess. It has been demonstrated that the ACTH-releasing
effect of ghrelin and GHS is purely mediated at the central level in physiological conditions; its enhancement in the presence
of ACTH-secreting tumours is, instead, likely to reflect direct action on GHS receptors present on the neoplastic tissues.
In fact, peculiar ACTH hyperresponsiveness to ghrelin and GHS has been observed also in ectopic ACTH-secreting tumours. 相似文献
956.
Intra-articular glucocorticoid injections are often used in patients with rheumatoid arthritis, either as bridging therapy or in periods with increased disease activity. We present a case of local skin depigmentation that occurred at the site of injection in a dark-skinned patient. Depigmentation is a rare complication of such therapy but may have important implications for dark-skinned patients.Abbreviations DMARD Disease-modifying anti-rheumatic drugs - RA Rheumatoid arthritis 相似文献
957.
Andrés?Felipe?Duque AmayaEmail author Adalberto?Gabriel?Díaz Torres Diego?Andrés?Acosta Maya 《International Journal on Interactive Design and Manufacturing》2016,10(4):401-415
A mathematical and numerical model of flow and combustion process for spark ignition engines is developed using the principles of the first and second law of thermodynamic. Availability (exergy) analysis is applied to cylinder of a spark ignition engine during the combustion process using a two-zone combustion model. Special attention is given to identification and quantification of irreversibility of combustion process and energy available basing on the isooctane fuel explosion. To predict emissions generation (greenhouse gases) a skeletal mechanism including 32 species and 61 reactions was developed and tested for different engine operations and exergy destructions. 相似文献
958.
Telomeres and Telomerase Biology in Vertebrates: Progress Towards a Non-Human Model for Replicative Senescence and Ageing 总被引:1,自引:0,他引:1
Studies on telomere and telomerase biology are fundamental to the understanding of human ageing and age-related diseases such
as cancer. However, human studies of whole body ageing are hampered by the lack of suitable fully reflective animal model
systems, the wild-type mouse model being unsuitable due to differences in telomere biology. Here we summarise recent data
on the biology of telomeres, telomerase, and the tumour suppressor protein p53 in various animals, and examine their possible
roles in replicative senescence, ageing, and tumourigenesis. The advantages and disadvantages of various animals as model
systems for whole body ageing in humans are discussed. 相似文献
959.
Bruserud O Tronstad KJ Berge R 《Journal of cancer research and clinical oncology》2005,131(6):377-384
Purpose Experimental in vitro models including well-characterised cell lines can be used to identify possible new therapeutic targets for the treatment of osteosarcoma. Culture media including inactivated serum is often recommended for in vitro culture of osteosarcoma cells, but the serum component then represents a nonstandardised parameter including a wide range of unidentified mediators. To improve the standardisation we have investigated whether serum-free culture media can be used in experimental in vitro studies of osteosarcoma cell lines.Methods The seven osteosarcoma cell lines Cal72, SJSA-1, Saos-2, SK-ES-1, U2OS, 143.98.2, and KHOS-32IH were cultured in vitro in various serum-free media and media supplemented with 10% heat-inactivated fetal calf serum (FCS).Results Although proliferation often was relatively low in serum-free media (X-vivo 10, X-vivo 15, X-vivo 20, Stem Span SFEM), some cell lines (Cal72, KHOS-32IH, Saos-2) showed proliferation comparable with the recommended FCS-containing media even when using serum-free conditions. The optimal serum-free medium then varied between cell lines. We also compared 6 different FCS-containing media (including Stem Span with 10% FCS) and the optimal FCS-containing medium varied between cell lines. However, all cell lines proliferated well in Stem Span with FCS, and this medium was regarded as optimal for four of the lines. FCS could not be replaced by fatty acids or low density lipoprotein when testing the Stem Span medium. The release of a wide range of soluble mediators showed only minor differences when using serum-free and FCS-containing media (including Stem Span with and without FCS), and serum-free Stem Span could also be used for in vitro studies of mitogen-stimulated T cell activation in the presence of accessory osteosarcoma cells. The use of Stem Span with 10% FCS allowed the release of a wide range of chemokines by osteosarcoma cell lines (Cal72, SJSA-1), and the chemokine release profile was very similar to the fibroblast lines Hs27 and HFL1.Conclusions Serum-free culture media can be used for in vitro studies of several osteosarcoma cell lines, but the optimal medium varies between cell lines and thus depends on: (i) the cell lines to be investigated/compared; (ii) the functional characteristic that is evaluated (proliferation, cytokine release); and (iii) whether coculture experiments are included. 相似文献
960.
Morris AA 《Journal of inherited metabolic disease》2005,28(2):109-121
Summary Ketone bodies (KBs) are an important source of energy for the brain. During the neonatal period, they are also precursors
for the synthesis of lipids (especially cholesterol) and amino acids. The rate of cerebral KB metabolism depends primarily
on the concentration in blood; high concentrations occur during fasting and on a high-fat diet. Cerebral KB metabolism is
also regulated by the permeability of the blood–brain barrier (BBB), which depends on the abundance of monocarboxylic acid
transporters (MCT1). The BBB’s permeability to KBs increases with fasting in humans. In rats, permeability increases during
the suckling period, but human neonates have not been studied. Monocarboxylic acid transporters are also present in the plasma
membranes of neurons and glia but their role in regulating KB metabolism is uncertain. Finally, the rate of cerebral KB metabolism
depends on the activities of the relevant enzymes in brain. The activities vary with age in rats, but reliable results are
not available for humans. Cerebral KB metabolism in humans differs from that in the rat in several respects. During fasting,
for example, KBs supply more of the brain’s energy in humans than in the rat. Conversely, KBs are probably used more extensively
in the brain of suckling rats than in human neonates. These differences complicate the interpretation of rodent studies. Most
patients with inborn errors of ketogenesis develop normally, suggesting that the only essential role for KBs is as an alternative
fuel during illness or prolonged fasting. On the other hand, in HMG-CoA lyase deficiency, imaging generally shows asymptomatic
white-matter abnormalities. The ability of KBs to act as an alternative fuel explains the effectiveness of the ketogenic diet
in GLUT1 deficiency, but its effectiveness in epilepsy remains unexplained. 相似文献