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41.
PURPOSE: A longitudinal biological study of 20 elite rowers was performed using capillary blood (serum) FT-IR spectra to evaluate their training load adaptations and fatigue. METHODS: Difference spectra (rest serum spectra subtracted to exercise serum spectra) were used to evaluate subjects' metabolic response to exercise. Spectra classifications were used for serum contents differentiation on the basis of biomolecular absorption. RESULTS: For two subjects, several metabolic differentiations were observed. These started with sugars metabolism on the fifth training week, followed successively by lipid metabolism and protein metabolism, when overtraining was clinically diagnosed. Several weeks further into the training program, the same onset of metabolic differentiations was observed for eight other subjects. When differentiations reached lipid metabolism, they were asked to reduce their training loads. Unlike the overtrained subjects, a rapid recovery was observed (3 vs 22 wk) and metabolism alterations disappeared. CONCLUSION: The fatigability limit in sportsmen seemed to be situated at a certain level of metabolic stress, beyond which a rapid overtraining process recover was no longer possible. 相似文献
42.
Dr. Íhsan Çaça MD Drs. Vatan Kavak PhD Dr. Kaan Ünlü MD Dr. Seyhmus Ari MD Dr. Yusuf Nergis PhD Dr. Gülnür Take MD 《Annals of Ophthalmology》2006,38(1):43-48
We evaluated the histopathological changes occurring in corneal endothelium after intracameral injection ropivacaine into
rats. Intracamerally administered ropivacaine in 1, 0.5, and 0.1% concentrations resulted in impairment of hexagonal structure
of corneal endothelial cells and inter-cellular junctions, destruction of microvilli on the cell surface, roughness of cell
borders, picnotic nucleus, diffuse vacuolization, and crystalysis in mitochondria.
The authors have stated that they do not have a significant financial interest or other relationship with any product manufacturer
or provider of services discussed in this article. The authors also do not discuss the use of off-label products, which include
unlabeled, unapproved, or investigative products or devices. 相似文献
43.
I Wórum T Fül?p J Csongor G Fóris A Le?vey 《Mechanisms of ageing and development》1984,28(2-3):315-324
The body composition of 40 healthy aged and 20 healthy young people was determined using a multi-isotope method. At the same time their hormonal status was assessed. A correlation between the body composition and the endocrine status was investigated. Our results concerning the body composition and the hormonal values correlate with the findings of the literature. A strong correlation was found between the plasma volume and the renin-angiotensin-aldosterone system. The interrelation could explain the reciprocal age related changes of plasma volume and the renin-angiotensin-aldosterone system. No or weak correlation could be found between the body composition and other measured hormones. 相似文献
44.
Delayed massive hemorrhage after pancreatic and biliary surgery: embolization or surgery? 总被引:12,自引:0,他引:12 下载免费PDF全文
de Castro SM Kuhlmann KF Busch OR van Delden OM Laméris JS van Gulik TM Obertop H Gouma DJ 《Annals of surgery》2005,241(1):85-91
OBJECTIVE: To analyze the management of delayed massive hemorrhage (DMH) after major pancreatic and biliary surgery. SUMMARY BACKGROUND DATA: Despite a decreased mortality rate for pancreatic and biliary surgery, DMH is still an important cause of postoperative mortality. The aim of the present study was to analyze the management of DMH after pancreatic and biliary surgery, and specifically to assess the role of embolization and surgical intervention. METHODS: The study group (SG) consisted of 1010 patients from 1994 to 2002 who underwent pancreatic or biliary surgery (cholecystectomy excluded). Patients from a previous study (1983-1993, n = 686) were used as a historical control group (HCG). RESULTS: The incidence of DMH (SG 2.3% vs. HCG 3.2%) declined somewhat but did not differ significantly between both periods. The number of patients with a septic complication (SG 74% vs. HCG 50%) and a sentinel bleed (SG 78% vs. HCG 100%) before the onset of DMH did not differ significantly. Embolization (SG 2 of 2 patients vs. HCG 0 of 2 patients) was not used frequently. Successful outcome after surgical intervention (SG 14 of 16 patients vs. HCG 8 of 14 patients) and the surgical procedures performed to obtain hemostasis were comparable and overall mortality (SG 22% vs. HCG 29%) was comparable. CONCLUSIONS: The incidence of DMH declined somewhat from 3.2% to 2.3% over the past years. Most patients present with septic complications and a sentinel bleed before onset of DMH. Despite general acceptance of embolization in our unit, it was used infrequently in patients with DMH. Aggressive surgical intervention was the treatment of choice in patients with DMH after pancreatic or biliary surgery. 相似文献
45.
Serrano-Martinez M Palacios M Martinez-Losa E Lezaun R Maravi C Prado M Martínez JA Martinez-Gonzalez MA 《European journal of nutrition》2005,44(6):348-354
Summary
Background
A
Mediterranean dietary pattern has
been associated with a reduced
risk of coronary heart disease, as
well as a reduction of oxidative
stress, but studies indicating possible
interactions between food intake
and inflammatory mediators
production at specific sites are
lacking.
Aim of the study
To assess
the relationship between Mediterranean
diet consumption and inflammatory
related molecules production
in coronary vessels.
Methods
A previously reported
Mediterranean–diet score was
computed summing–up the quintiles
of eight dietary components
from a validated food frequency
questionnaire in 24 patients with
unstable angina. Tumor necrosis
factor (TNF–α) and vascular cell
adhesion molecule (VCAM–1) concentrations
were measured in
coronary sinus blood.
Results
Both
biomarkers showed an inverse association
with the Mediterraneandiet
score. The association between
VCAM–1 and the Mediterranean–diet score had an adjusted
β coefficient of –35.1 ng/ml (95%
coefficient interval, CI: –63.5 to
–6.7). The adjusted β coefficient
using TNF–α as the dependent
variable was –41.6 pg/ml (95 % CI:
–76.2 to –7.1). The consumption of
olive oil as a single item showed a
significant inverse association, and
a Mediterranean–diet score
excluding olive oil was also inversely
associated with TNF–α and
VCAM–1 serum levels in coronary
venous blood.
Conclusions
Adherence
to a Mediterranean dietary
pattern may protect against coronary
artery wall production of
inflammatory mediators. This
finding could provide a novel
mechanistic explanation for the
recognized lower coronary risk
associated with a Mediterranean
diet. 相似文献
46.
Kraemer CK Menegon DB Cestari TF 《Photodermatology, photoimmunology & photomedicine》2005,21(5):242-248
BACKGROUND: The use of an adequate initial dose of ultraviolet A (UVA) radiation for photochemotherapy is important to prevent burns secondary to overdosage, meanwhile avoiding a reduced clinical improvement and long-term risks secondary to underdosage. The ideal initial dose of UVA can be achieved based on the phototype and the minimal phototoxic dose (MPD). The objective measurement of constitutive skin color (colorimetry) is another method commonly used to quantify the erythematous skin reaction to ultraviolet radiation exposure. The aim of this study was to determine variations in MPD and constitutional skin color (coordinate L(*)) within different phototypes in order to establish the best initial dose of UVA radiation for photochemotherapy patients. METHODS: Thirty-six patients with dermatological conditions and 13 healthy volunteers were divided into five groups according to phototype. Constitutional skin color of the infra-axillary area was assessed by colorimetry. The infra-axillary area was subsequently divided into twelve 1.5 cm(2) regions to determine the MPD; readings were performed 72 h after oral administration of 8-methoxypsoralen (MOP) followed by exposure of the demarcated regions to increasing doses of UVA. Results: The majority of the participants were women (73.5%) and their mean age was 38.8 years. The MPD ranged from 4 to 12 J/cm(2) in phototypes II and III; from 10 to 18 J/cm(2) in type IV; from 12 to 24 J/cm(2) in type V and from 18 to 32 J/cm(2) in type VI. The analysis of colorimetric values (L(*) coordinate) and MPD values allowed the definition of three distinctive groups of individuals composed by phototypes II and III (group 1), types IV and V (group 2), and phototype VI (group 3). CONCLUSIONS: MPD and L(*) coordinate showed variation within the same phototype and superposition between adjacent phototypes. The values of the L(*) coordinate and the MPD lead to the definition of three distinct sensitivity groups: phototypes II and III, IV and V and type VI. Also, the MPD values bear a strong correlation to coordinate L(*) values. Mean MPD values described for each of the three major sensitivity groups were higher than the values commonly used in clinical settings for the different phototypes. Therefore, phototype alone is not a good parameter to define the initial UVA dose. MPD and colorimetry could be used in pre-treatment evaluation of patients who are to be submitted to photochemotherapy, in a non-invasive and more accurate way when compared with the classical phenotype clinical criteria. 相似文献
47.
Previous studies showed that bile duct injury after cholecystectomy is associated with substantial morbidity and a negative effect on Quality of Life. In a recent study, patients with a bile duct injury after cholecystectomy exhibited a 3-fold increase in mortality during a follow-up period of nine years compared to patients without injury. This is the first study to demonstrate a negative impact of bile duct injury on survival. Repair by a less experienced surgeon leads to an 11% higher mortality during follow-up. Cholangiography should probably be performed routinely during cholecystectomy. A bile duct lesion should be suspected when the patient has not recovered within 48 hours. Endoscopic or percutaneous treatment of stenoses or leakage is usually successful, even after several weeks. 相似文献
48.
Shinkaruk S Bayle M Laïn G Déléris G 《Current Medicinal Chemistry-Anti-Cancer Agents》2003,3(2):95-117
Angiogenesis is a process of development and of growth of new capillary blood vessels from pre-existing vessels. When pathological, it contributes to the development of numerous types of tumors, and the formation of metastases. In order to grow, carcinoma need new blood vessels to form so that they can feed themselves. Therefore, nowadays the concept according to which the development of cancer is angiogenesis dependent is generally recognized. This concept makes the control of tumoral angiogenesis one of the promising therapeutic ways in cancerology. The transition from the latent phase to the invasive and metastatic phase of a cancer is linked to what is called the angiogenic switch. It implies complex cellular and molecular interactions between cancerous cells, endothelial cells and the components of the extra-cellular matrix and namely the existence of specific proteins secreted by the tumoral cells able to stimulate the proliferation of capillary endothelial cells. Among them, VEGF, Vascular Endothelial Growth Factor was found in several types of tumors. It has shown a tumoral angiogenic activity in vitro and in vivo, and thus is a privileged target for the control of angiogenesis in an anti-tumoral goal. The role of VEGF in tumoral angiogenesis has been extensively studied. It has been proved to undergo as well autocrine as paracrine stimulation of tumoral angiogenesis. During the last few years, several members of the VEGF family have been described namely the VEGF-A, B, C, D, E and placenta growth factor (PlGF) among which VEGF-A (121 aminoacids) plays a role of prime importance in angiogenesis. VEGF is a 45 kDA glycoprotein, homodimeric, basic, and able to bind heparin. The three-dimensional structure of VEGF has been recently determined, by X-rays diffraction, and NMR spectroscopy. The different forms of the VEGF bind to receptors that exhibit a tyrosine-kinase activity (RTK). The specific action of the VEGF on the endothelial cells is mainly regulated by two types of RTK of the VEGF family, VEGFR1, or Flt-1, and VEGFR2, or KDR/Flk-1. Mutagenesis studies have shown that only a small number of VEGF residues are important and essential for the binding with RTK. Data described to date from the studies of VEGF/RTK interactions agree to the hypothesis that KDR receptor is the main human receptor responsible for the VEGF activity in both physiological and pathological vascular development, and VEGF-KDR signalling pathway has been validated as a priority target for the development of anti- and pro- angiogenic agents. Therefore angiogenesis mediated by VEGF constitutes a new target for anti-cancer therapy which has explored through different ways of intervention aiming at the blocking of the tumoral angiogenesis. The main ones are: -Struggle against the stroma degradation and invasion by the neo-vessels -Inhibition of activated endothelial cells. -Inhibition of angiogenic factors production and of their receptors. -Inhibition of the VEGF signal pathway, by peptides blocking the bond between VEGF and its receptors through the inhibition of intracellular transduction of VEGF signal. In conclusion, this bibliographic study allows to situate works of medicinal chemistry in the context of present knowledge concerning the vascular endothelial growth factor (VEGF) and its role in angiogenesis. 相似文献
49.
Etienne-Jules Marey introduced gait motion analysis at the end of the XIXth century. It was rapidly adopted by clinicians and Charcot used it at the beginning of the XXth century in La Salpêtrière. Motion analysis was widely used after the first optoelectronic system was built by Furné in 1968. The optoelectronic system calculates the orientation of each body segment in the space after the determination of the space co-ordinates of cutaneous markers placed over them. It is particularly useful for spastic gait. Many disturbances of kinematics and kinetics have been described during spastic gait. They are the consequences of spasticity and other motor and sensory deficits of central nervous system lesions. Motion analysis must be coupled with electromyographic recording of spastic muscles activity which, with kinetic analysis, enables distinguishing the mechanisms underlying gait disturbances. Motion analysis provides clinicians with an indispensable tool for understanding spasticity and evaluating therapeutic efficacy. 相似文献
50.
Denys P Even-Schneider A Rémy-Néris O Ben Smaïl D Chartier-Kastler E Bussel B 《Neuro-Chirurgie》2003,49(2-3 PT 2):395-398
Intrathecal clonidine was tested for the control of bladder hyperreflexia resistant to pararsympathicolytic drugs in spinal cord injured patients. Urodynamic parameters were significantly improved after acute bolus of intrathecal low doses of clonidine. Unfortunately, the chronic intrathecal infusion of clonidine induced cardiovascular side-effects. Intrathecal baclofen did not modified significantly neurogenic bladder dysfunction from spinal lesion. But intrathecal baclofen modified penile erection quality and impaired the ejaculation reflex induced by penile vibratory stimulation in the same population. 相似文献