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81.
Harnaen EJ Na AF Shenker NS Sourial M Farmer PJ Southwell BR Hutson JM 《Journal of pediatric surgery》2007,42(12):1982-1987
Background
Extrapolation of rat testicular descent studies to humans has been criticized because of anatomical differences of the cremaster muscle. Human cremaster is described as a thin strip rather than a large, complete sac as in rats, which is proposed to be more important in propelling the testis during descent. This study investigated cremaster muscle anatomy and ontogeny in both normal and cryptorchid rat models.Methods
Gubernacula from 4 groups of neonatal rats were sectioned longitudinally and transversely: normal Sprague-Dawley, capsaicin pretreated, flutamide pretreated, and congenital cryptorchid rats. Gubernacula were stained with hematoxylin-eosin, Masson trichrome, and desmin immunohistochemistry to study muscle development.Results
Myoblasts are more numerous at the gubernacular tip, whereas the most differentiated muscle is proximal. Rat cremaster develops as an elongated strip rather than a complete sac derived from abdominal wall muscles. Flutamide and capsaicin pretreatment disrupts development.Conclusion
Rat cremaster muscle develops as a strip, bearing close resemblance to human cremaster muscle, permitting extrapolation of cremaster function to human testicular descent. The cremaster muscle appears to differentiate from the gubernacular tip during elongation to the scrotum, and requires intact sensory innervation and androgen. 相似文献82.
Abdel-Moneim Ahmed S. Shany Salama A. S. Fereidouni Sasan R. Eid Bahaa T. M. El-Kady Magdy F. Starick Elke Harder Timm Keil Günther M. 《Archives of virology》2009,154(9):1559-1562
Archives of Virology - The sequences encoding the haemagglutinin (HA) of twelve H5N1 isolates obtained in 2006 and 2007 from different avian species in backyard holdings and poultry farms in Egypt... 相似文献
83.
Several beneficial effects of splenectomy on the liver integrity have been recently reported by both experimental and clinical studies. However, the effects of splenectomy on hepatic functional reserve and structural damage in patients with chronic hepatitis C (CHC) were not studied by objective evidence. The aim of this study was to assess the effect of splenectomy on hepatic functional reserve and structural damage in patients with CHC by non-invasive serum markers. The study involved 22 patients with histopathological diagnosis of CHC undergoing splenectomy for treatment of associated hypersplenism. The hepatic functional reserve and structural damage markers were assessed before and after splenectomy surgery on the 2nd and 60th postoperative days by aspartate aminotransferase to alanine aminotransferase (AST/ALT ratio), AST to platelet ratio index (APRI) and serum levels of gamma-glutamyl transferase (GGT), hyaluronic acid (HA), type IV collagen (CIV) and tissue inhibitor of metalloproteinase-1 (TIMP-1). After splenectomy, the levels of serum HA showed a significant decrease in relation to the preoperative values both in PO-1 (mean pre-splenectomy: 272+/-88.6 versus 185+/-77.4 ng/ml; P=0.01) and PO-2 (169+/-58.1 ng/ml; 0.017). The levels of type IV collagen showed a significant decrease in relation to the preoperative values both in PO-1 (mean pre-splenectomy: 208+/-134 versus 125+/-100 ng/ml; P=0.01) and PO-2 (121+/-74.7 ng/ml; P=0.02). Serum levels of TIMP-1 also showed a significant decrease in relation to the preoperative values both in PO-1 (mean pre-splenectomy: 764+/-571 versus 261+/-195 ng/ml; P=0.006) and PO-2 (149+/-110.1 ng/ml; P=0.004). There was no significant difference between PO-1 and PO-2 mean values for each of those serum markers. This study found that splenectomy induced a reduction of biochemical markers of liver functional reserve and fibrosis in patients with chronic hepatitis C which reflect a change in the processes involved in of liver fibrosis. However, it cannot be concluded whether this reflects a change in the rate of its progression or a prevention of further fibrosis. 相似文献
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86.
Marco Metra Marianna Adamo Daniela Tomasoni Alexandre Mebazaa Antoni Bayes-Genis Magdy Abdelhamid Stamatis Adamopoulos Stefan D. Anker Johann Bauersachs Yuri Belenkov Michael Böhm Tuvia Ben Gal Javed Butler Alain Cohen-Solal Gerasimos Filippatos Finn Gustafsson Loreena Hill Tiny Jaarsma Ewa A. Jankowska Mitja Lainscak Yuri Lopatin Lars H. Lund Theresa McDonagh Davor Milicic Brenda Moura Wilfried Mullens Massimo Piepoli Marija Polovina Piotr Ponikowski Amina Rakisheva Arsen Ristic Gianluigi Savarese Petar Seferovic Rajan Sharma Thomas Thum Carlo G. Tocchetti Sophie Van Linthout Cristiana Vitale Stephan Von Haehling Maurizio Volterrani Andrew J.S. Coats Ovidiu Chioncel Giuseppe Rosano 《European journal of heart failure》2023,25(7):1115-1131
Acute heart failure is a major cause of urgent hospitalizations. These are followed by marked increases in death and rehospitalization rates, which then decline exponentially though they remain higher than in patients without a recent hospitalization. Therefore, optimal management of patients with acute heart failure before discharge and in the early post-discharge phase is critical. First, it may prevent rehospitalizations through the early detection and effective treatment of residual or recurrent congestion, the main manifestation of decompensation. Second, initiation at pre-discharge and titration to target doses in the early post-discharge period, of guideline-directed medical therapy may improve both short- and long-term outcomes. Third, in chronic heart failure, medical treatment is often left unchanged, so the acute heart failure hospitalization presents an opportunity for implementation of therapy. The aim of this scientific statement by the Heart Failure Association of the European Society of Cardiology is to summarize recent findings that have implications for clinical management both in the pre-discharge and the early post-discharge phase after a hospitalization for acute heart failure. 相似文献
87.
Dina S. El-Kafrawy Amira H. Abo-Gharam Magdy M. Abdel-Khalek Tarek S. Belal 《Sustainable Chemistry and Pharmacy》2022
According to green analytical chemistry (GAC) principles, multi-analyte methods are usually more preferred than methods determining one analyte at a time (principle 8) as they allow saving resources (time, reagents and money) (principle 9) and permit the reduction of generated waste (principle 7) as well as reduction of needed samples (principle 2). The present work herein, describes for the first time the development, validation and comparison of novel green versatile multi-analyte HPLC-DAD and HPTLC methods for the quantitative estimation of five drugs (diacerein, aceclofenac, diclofenac sodium, celecoxib and meloxicam) within a single run in a short analysis time. For HPLC-DAD, separation was performed through using Zorbax SB C18 (4.6 × 250 mm, 5 μm particle size) with the mobile phase composed of 0.05 M phosphate buffer pH 3.0 and acetonitrile (42:58, v/v) at a flow rate of 1 mL/min. The chromatograms were extracted at 258, 276 and 355 nm. In HPTLC procedure, precoated TLC silica gel aluminum plates 60 F254 were used with a mobile phase consisting of mixture of (chloroform: methanol: acetic acid, 92:8:0.25, v/v/v). The developed plates were scanned densitometrically at 258, 280 and 360 nm. Validation of the proposed methods was performed following the ICH guidelines for linearity, ranges, precision, accuracy, robustness, detection and quantification limits. Good linearities were confirmed by the high values of correlation coefficients (r > 0.9992). Appraisal of the greenness of the developed methods and comparison with different reported chromatographic methods was performed using the analytical Eco-scale (AES) approach and the novel Analytical GREEnness (AGREE) metric. 相似文献
88.
Macrophage migration inhibitory factor: a therapeutic target across inflammatory diseases 总被引:4,自引:0,他引:4
Macrophage migration inhibitory factor (MIF), a cytokine originally reported in the 1960s as the prototypic T lymphokine, has emerged in recent years as a key factor regulating inflammatory responses. Both by directly activating immune cells, and by participating in activation entrained by other stimuli, MIF is important in innate and adaptive immune responses as well as tissue-specific mechanisms of damage. As a consequence of its involvement in multiple stages of the immune-inflammatory response, MIF has the potential to be involved in the pathogenesis of a range of immune-mediated inflammatory diseases affecting multiple organ systems. Diseases in which a role for MIF has been strongly validated include rheumatoid arthritis, inflammatory bowel disease, multiple sclerosis, atherosclerosis, asthma, inflammatory liver disease, and most recently systemic lupus erythematosus. Recent data have provided mechanisms of action for MIF which further support its suitability as a therapeutic target. Finally, MIF has a unique relationship with glucocorticoids, acting to counter-regulate their anti-inflammatory effects, such that MIF antagonist therapy may be a direct route to 'steroid-sparing'. Methods of targeting MIF therapeutically have also emerged in recent years, based on the unique protein structure of MIF which affords opportunities for direct antagonism by small molecules, as well as by protein therapeutics such as monoclonal antibodies. Clinical trials of MIF antagonist therapies are likely before the end of the current decade. 相似文献
89.