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91.
Rats were made cryptorchid, bi- or unilaterally, by cutting gubernaculum testis at birth. At 100 days of age the basal plasma testosterone concentration was smaller in bilateral cryptorchid animals as compared to unilateral cryptorchid and control rats. After acute LH-stimulation plasma testosterone concentration increased in all rats, where the highest concentrations were found in the control group. The amount of testosterone in the testis after a 30 min LH-stimulation was lower in both kinds of cryptorchid testes but higher in the scrotal testis of the unilateral cryptorchid rats, all as compared to control testis. This decreased effect of LH observed in cryptorchid animals indicates an impaired Leydig cell function in cryptorchid testis. The results also show a compensatory hyperfunction of Leydig cells in the scrotal testes of unilateral cryptorchid rats. It was also found that the intratesticular concentration of oestradiol-17 beta was three-fold increased in unilateral cryptorchid testes and even more in bilateral cryptorchid ones. 相似文献
92.
Shahrokh F. Shariat Robert S. Svatek Derya Tilki Eila Skinner Pierre I. Karakiewicz Umberto Capitanio Patrick J. Bastian Bjoern G. Volkmer Wassim Kassouf Giacomo Novara Hans‐Martin Fritsche Jonathan I. Izawa Vincenzo Ficarra Seth P. Lerner Arthur I. Sagalowsky Mark P. Schoenberg Ashish M. Kamat Colin P. Dinney Yair Lotan Michael J. Marberger Yves Fradet 《BJU international》2010,105(10):1402-1412
Study Type – Prognosis (retrospective cohort)Level of Evidence 2b
OBJECTIVE
To externally validate the prognostic value of lymphovascular invasion (LVI) in a large international cohort of patients treated with radical cystectomy (RC) for urothelial carcinoma of the bladder (UCB).PATIENTS AND METHODS
We collected data from 4257 patients treated with RC and pelvic lymphadenectomy for UCB, without neoadjuvant chemotherapy, at 12 centres. LVI was defined as presence of nests of tumour cells within an endothelium‐lined space.RESULTS
LVI was detected in 1407 patients (33.1%); the proportion of LVI increased with advancing stage, higher grade, soft‐tissue surgical margin involvement, and lymph node metastasis (P < 0.001 for all). In standard multivariate models, LVI was associated with both disease recurrence (hazard ratio 1.43, P < 0.001) and cancer‐specific mortality (1.45, P < 0.001). In the entire cohort, adding LVI to a base model that included standard features improved only minimally its predictive accuracy for both recurrence and cancer‐specific mortality (by 1.1% and 1.2%, respectively). In 3122 patients with negative lymph nodes, LVI remained independently associated with and improved the predictive accuracy of the standard predictors for recurrence (hazard ratio 1.68, P < 0.001; +2.3%) and cancer‐specific mortality (1.70, P < 0.001; +2.4%). By contrast, in 1071 node‐positive patients, LVI only marginally improved the prediction of cancer‐specific recurrence (hazard ratio 1.20, P < 0.001; +0.2%) and survival (1.23, P < 0.001; +0.5%).CONCLUSIONS
LVI is strongly associated with clinical outcome in node‐negative patients treated with RC. The assessment of LVI might help to identify patients who could benefit from adjuvant therapy after RC. After confirmation in different populations, LVI should be included in the staging of UCB. 相似文献93.
Nedim Selimovic Bert Andersson Claes‐Håkan Bergh Gunnar Mårtensson Folke Nilsson Odd Bech‐Hanssen Bengt Rundqvist 《Transplant international》2008,21(4):314-319
Lung transplantation (LTx) is a therapeutic option for patients with end-stage lung disease. However, the mortality rate of patients on the waiting list is high. The purpose of this study was to examine the prognostic value of cardio-pulmonary hemodynamics for death in patients awaiting LTx. Retrospectively, 177 patients with advanced lung disease accepted for LTx at Sahlgrenska University Hospital from January 1990 through December 2003 were studied. Patient demographics, pulmonary function tests, gas exchange and hemodynamic variables were included in the analysis. Death while awaiting LTx was the primary endpoint for all analyses. Mean age was 49 +/- 9 years. Main diagnoses were alpha 1 antitrypsin deficiency (n = 56), chronic obstructive pulmonary disease (n = 61), cystic fibrosis (n = 14) and interstitial lung disease (n = 46). Thirty patients died (17%). LTx was performed in 143 cases. By univariate analyses, forced vital capacity (FVC) % of predicted, pulmonary vascular resistance (PVR) and diagnosis were associated with risk for death. In multivariate analysis PVR (HR, 1.22; 95% CI, 1.06-1.41; P = 0.006) and FVC% of predicted (HR, 0.97; 95% CI, 0.94-0.99; P = 0.01) were independently associated with death. Patients with increased PVR and a lower FVC % of predicted awaiting LTx should be considered for a higher organ allocation priority. Assessment of pulmonary hemodynamics needs to be considered during evaluation for LTx. 相似文献
94.
95.
Voltage-sensitive calcium channels (VSCC) open in response to external stimuli, including calcitropic hormones, that alter plasma membrane calcium (Ca2+) permeability. Ca2+ that enters the cell through these channels serves a second messenger function, eliciting cellular responses that include secretion and changes in gene expression. In osteoblasts, VSCCs serve as key regulators of Ca2+ permeability and are a major class of calcitropic hormone-sensitive Ca2+ channels present in the plasma membrane. The members of the VSCC family exist as a complex of polypeptide subunits that are comprised of a pore-forming 1 subunit, an intracellular subunit, a dimer of disulfide-linked 2 and subunits, and in some tissues, a subunit. Previous studies in our laboratory have shown that the major functional 1 subunit present in osteoblasts is the 1C (CaV1.2). To determine the complement of auxiliary subunits present in rodent osteoblastic cells, we employed RT-PCR using a battery of subunit specific primers and appropriate tissue controls. Immunohistochemistry also was performed, using available subunit specific antibodies, to measure protein expression and localization. Cell types examined included MC3T3-E1 at various stages of differentiation, ROS 17/2.8 osteosarcoma, and primary cultures of rat calvarial osteoblasts. The results indicate that all cells expressed multiple subunit classes and 2 dimers, but no subunits, regardless of differentiation state. We propose a structure for the functional osteoblast VSCC that consists of 1, , 2 subunits and is devoid of a subunit. 相似文献
96.
97.
Modjtaba Zandian Ioannis Ioakimidis Cecilia Bergh Per S?dersten 《Physiology & behavior》2009,96(4-5):518-521
It has been suggested that restrained eating is a cognitive strategy that an individual uses for control of food intake. If losing control, the restrained eater enters a state of disinhibition and is therefore thought to be at risk for developing eating disorders and obesity. Restrained eaters eat at a constant rate and can therefore also be referred to as linear eaters. Here, we have tested the hypothesis that restrained eating is a state that can be modified by teaching linear eaters to eat at a decelerated rate. Seventeen female linear eaters scored high on a scale for restrained eating. When challenged to eat at an increased rate, a test of disinhibition, the women overate by 16% on average. The women then practiced eating at a decelerated rate by use of feedback from a training curve displayed on a computer screen during the meals. The training occurred three times each week and lasted eight weeks. When re-tested in the absence of feedback, the women ate at a decelerated rate, they did not overeat in the test of disinhibition and they scored lower on the scale for restrained eating. It is suggested that restrained eating is a state that can be reduced by training. 相似文献
98.
Stephan Pauly David Fiebig Bettina Kieser Bjoern Albrecht Alexander Schill Markus Scheibel 《Knee surgery, sports traumatology, arthroscopy》2011,19(12):2090-2097
Background
Biomechanical comparison of four different Speed-Bridge configurations with or without medial or lateral row reinforcement. Reinforcement of the knotless Speed-Bridge double-row repair technique with additional medial mattress- or lateral single-stitches was hypothesized to improve biomechanical repair stability at time zero. 相似文献99.
100.
Vascular regrowth following photodynamic therapy in the chicken embryo chorioallantoic membrane 总被引:1,自引:0,他引:1
Patrycja Nowak-Sliwinska Judy R. van Beijnum Maaike van Berkel Hubert van den Bergh Arjan W. Griffioen 《Angiogenesis》2010,13(4):281-292
Photodynamic therapy (PDT) induces damage to the endothelium, which can lead to increased vascular permeability and, under intensive PDT conditions, even to platelet aggregation, vasoconstriction, and blood flow stasis. Eventually, ischemia, hypoxia, and inflammation can occur, resulting in angiogenesis. We studied the sequence of the vascular events after Visudyne®-PDT in the chicken chorioallantoic membrane (CAM) at day 11 of development. Using epi-fluorescence microscopy, we monitored the regrowth of capillaries in the PDT treated area. Immediately after irradiation, the treatment resulted in blood flow arrest. And 24 h post PDT, sprouting of new blood vessels was observed at the edge of the PDT zone. Neovessels looping out from the edge of the PDT zone gave rise to specialized endothelial tip structures guiding the vessels towards the center of the treated area. At 48 h almost all of the treated area was repopulated with functional but morphologically altered vasculature. These observations also showed reperfusion of some of the vessels that had been closed by the PDT treatment. CAM samples were immunohistochemically stained for Ki-67 showing proliferation of endothelial cells in the PDT area. Also, several markers of immature and angiogenic blood vessels, such as αVβ3-integrin, vimentin and galectin-1, were found to be enhanced in the PDT area, while the endothelial maturation marker intercellular adhesion molecule (ICAM)-1 was found to be suppressed. These results demonstrate that the new vascular bed is formed by both neo-angiogenesis and reperfusion of existing vessels. Both the quantitative real-time RT–PCR profile and the response to pharmacological treatment with Avastin®, an inhibitor of angiogenesis, suggest that angiogenesis occurs after PDT. The observed molecular profiling results and the kinetics of gene regulation may enable optimizing combination therapies involving PDT for treatment of cancer and other diseases. 相似文献