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81.
Caja S Torrente M Martínez I Abelenda M Puerta M 《Journal of endocrinological investigation》2005,28(7):609-615
Adiponectin is believed to be a key factor in determining insulin sensitivity. In turn, insulin sensitivity is known to change from an enhanced state in early pregnancy to a reduced one in late pregnancy. A role for adiponectin in these changes has been proposed for mice but questioned for humans. We addressed this issue in rats by measuring adiponectin expression in both visceral and subcutaneous white adipose tissue, together with tissue content and release of the hormone in non-pregnant and in pregnant rats by days 8, 15 and 19 of pregnancy. Plasma concentration was also determined. No differences were found in any of the parameters measured between non-pregnant and pregnant rats at any time of pregnancy despite changes in white adipose tissue mass and insulin sensitivity. Adiponectin was also detected in cerebrospinal fluid at a concentration 1,000 times lower than in plasma, but again no differences were found between non-pregnant and pregnant animals. It is concluded that adiponectin does not play any role in regulating changes in insulin sensitivity during pregnancy in rats. 相似文献
82.
Human skin-derived stem cells migrate throughout forebrain and differentiate into astrocytes after injection into adult mouse brain 总被引:15,自引:0,他引:15
Belicchi M Pisati F Lopa R Porretti L Fortunato F Sironi M Scalamogna M Parati EA Bresolin N Torrente Y 《Journal of neuroscience research》2004,77(4):475-486
Recent evidence indicates that neural stem cell properties can be found among a mammalian skin-derived multipotent population. A major barrier in the further characterization of the human skin-derived neural progenitors is the inability to isolate this population based on expression of cell surface markers. Our work has been devoted to purified human skin-derived stem cells that are capable of neural differentiation, based on the presence or absence of the AC133 cell surface marker. The enriched skin-derived AC133(+) cells express the CD34 and Thy-1 antigens. These cells cultured in a growth medium containing epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) proliferate, forming spheres, and differentiate in vitro into neurons, astrocytes, and rarely into oligodendrocytes. Single cells from sphere cultures initiated from human purified AC133(+) cells were replated as single cells and were able to generate new spheres, demonstrating the self-renewing ability of these stem cell populations. Brain engraftment of cells obtained from human purified AC133(+)-derived spheres generated different neural phenotypes: immature neurons and a most abundant population of well differentiated astrocytes. The AC133-derived astrocytes assumed perivascular locations in the frontal cortex. No donor-derived oligodendrocytes were found in the transplanted mouse brains. Several donor small, rounded cells that expressed endothelial markers were found close to the host vessel and near the subventricular zone. Thus, mammalian skin AC133-derived cells behave as a multipotent population with the capacity to differentiate into neural lineages in vitro and, prevalently, endothelium and astrocytes in vivo, demonstrating the great plasticity of these cells and suggesting potential clinical application. 相似文献
83.
Bandelow B Charimo Torrente A Wedekind D Broocks A Hajak G Rüther E 《European archives of psychiatry and clinical neuroscience》2004,254(6):397-405
Objective
Childhood traumatic experiences,
rearing styles, familial mental disorders and birth
risk factors have been associated with the development
of social anxiety disorder.
Method
Patients with social
anxiety disorder (n = 50) and healthy controls (n = 120)
were investigated using a retrospective interview with
203 questions.
Results
The frequency of reports of traumatic
childhood experiences was significantly higher in
patients than in controls, including separation from parents,
parents marital discord, sexual abuse, familial violence,
childhood illness, and other factors. On a 0–10
point severe trauma scale patients had significantly
higher mean scores (2.0; SD 1.28) than control subjects
(0.82; SD 1.1; p < 0.0001).Only 6 (12 %) of the social phobic
patients, but 63 (52.5%) of the controls did not report
any severe traumatic events at all (2= 24.0; p <
0.0001). Compared to controls, patients described their
parents rearing styles as significantly more unfavourable.
Patients reported higher rates of psychiatric
disorders in their families in general, in particular anxiety
disorders, depression, and suicidality. Birth risk factors
did not differ between patients and controls. In a logistic
regression model, the highest contribution was
noted for familial anxiety disorders. Separation from
parents also had a significant, but smaller influence.
There was only a trend towards a significant contribution
of childhood sexual abuse. Violence in the family,
parental rearing styles and birth risk factors did not
contribute significantly.
Conclusions
The present data
suggest that the aetiology of social anxiety disorder is
multifactorial and that familial mental disorders and
separation experiences are the most important contributing
factors. 相似文献
84.
Sánchez-Fructuoso AI Prats D Marques M Ridao N Conesa J García Mena M Torrente J Barrientos A 《Transplantation proceedings》2003,35(5):1689-1690
BACKGROUND: Recent reports have demonstrated the efficacy of interleukin-2-receptor blockers in lowering the incidence of early acute rejection. The present study aimed to test the hypothesis that the use of daclizumab induction (DAC) plus low-dose tacrolimus, mycophenolate mofetil, and steroid diminishes the incidence of delayed graft function (DGF) in renal transplants from non-heart-beating donors (NHBD). METHODS: We compared the incidence of DGF and rejection in 185 renal transplants from NHBD treated as follows: Group-I: quadruple sequential therapy with antithymocyte globulin, cyclosporine, azathioprine, and steroids (n=22); Group-II: cyclosporine (8 mg/kg/d) plus azathioprine plus steroid (n=26); Group-III: low-dose cyclosporine (5 mg/kg/d) plus mycophenolate mofetil plus steroid (n=68); Group-IV: low-dose tacrolimus (0.1 mg/kg/d) plus mycophenolate mofetil plus steroid (n=17); and Group-V: DAC plus low-dose tacrolimus plus mycophenolate mofetil plus steroid (n=43). RESULTS: The incidences of DGF were 72.7% in Group-I, 73.1% in Group-II, 69.1% in Group-III, 76.5% in Group-IV, and 44.2% in Group-V. Acute rejection was higher in Group-IV. CONCLUSIONS: The combination of DAC, low-dose tacrolimus, mycophenolate mofetil, and steroids is effective in lowering the incidence of DSF in NHBD kidney transplant recipients without any increase in acute rejection. 相似文献
85.
de Diego Fernández R Tisner Madrid ML Cabrerizo Torrente P Sanjoaquín Mur T 《Revista espa?ola de anestesiología y reanimación》2003,50(4):182-187
OBJECTIVES: The purpose of this study was to compare two 27-gauge anesthesia needles with different points (a Whitacre-type point and a Quincke-type point) and to assess the incidences of postdural puncture headache (PDPH), puncture difficulty and failed anesthesia. MATERIAL AND METHODS: This prospective, randomized and double-blind trial enrolled 1,555 patients receiving spinal anesthesia for lower abdominal surgery. No age limits were established. A 27-gauge Whitacre-point needle was used in group I (n = 748) and a 27-gauge Quincke-point needle was used in group II (n = 774). RESULTS: The incidences of PDPH were significantly different in groups I (0.53%) and II (1.85%) (p < 0.01). Puncture was easy in 84.89% of the procedures in group I and in 78.81% in group II (p < 0.01). The number of cases in which a puncture could not be accomplished was similar in the two groups (2.41% in group I and 2.07% in group II). The number of failed anesthetic procedures was also similar (0.96% in group I and 1.45% in group II). CONCLUSIONS: When a 27-gauge Whitacre-point needle is used, fewer cases of PDPH develop and the puncture is easier to accomplish than when a Quincke-point needle is used. The number of failed anesthetic procedures is similar with both needles. Whitacre-point 27-gauge needles are preferable to Quincke-point 27-gauge needles. 相似文献
86.
Sánchez-Fructuoso AI Prats D Pérez-Contín MJ Marques M Torrente J Conesa J Grimalt J Del Rio F Núñez JR Barrientos A 《Transplantation》2003,76(8):1180-1184
OBJECTIVES: En bloc pediatric kidney transplants (EBPKT) are still a subject of controversy. The aim of this study was to determine whether acceptable long-term graft survival and function can be achieved in EBPKT compared with the transplant of single, cadaveric, adult donor kidneys. METHODS: A retrospective review was conducted of 66 recipients of en bloc kidneys from cadaveric pediatric donors and 434 patients who underwent transplantation with a single kidney from an adult donor between January 1990 and May 2002 at the authors' hospital. The recipients were well-matched demographically. Both transplant groups were analyzed for short- and long-term performance in terms of transplant outcome and quality of graft function. RESULTS: Overall death-censored actuarial graft survival rates at 1 and 5 years were 89.2% and 84.6% in the adult kidney transplants (AKT) and 83.3% and 81.1% in EBPKT, respectively (P=0.56). In the EBPKT group, graft function was improved over that observed in AKT. Vascular thrombosis was the most common cause of graft loss in EBPKT. Acute rejection occurred more frequently in AKT and Cox's regression analysis indicated that undergoing an AKT was a predictive factor for acute vascular rejection (adjusted risk ratio, 3.8; 95% confidence interval, 1.4-10.2; P=0.001). CONCLUSIONS: Overall graft survival was similar in both groups, vascular complications were the main cause of graft loss in EBPKT, and the EBPKT showed excellent long-term graft function and a low incidence of acute rejection. 相似文献
87.
OBJECTIVE: To determine whether children's food consumption is increased by the size of the group of children in which they are eating. DESIGN: Crossover study. SETTING: University based preschool. PARTICIPANTS: 54 children, aged 2.5-6.5 years. INTERVENTIONS: Each child ate a standardised snack in a group of three children, and in a group of nine children. MAIN OUTCOME MEASURES: Amount each individual child consumed, in grams. RESULTS: Amount eaten and snack duration were correlated (r = 0.71). The association between group size and amount eaten differed in the short (<11.4 min) versus the long (> or =11.4 min) snacks (p = 0.02 for the interaction between group size and snack duration). During short snacks, there was no effect of group size on amount eaten (16.7 (SD 11) g eaten in small groups vs 15.1 (6.6) g eaten in large groups, p = 0.42). During long snacks, large group size increased the amount eaten (34.5 (16) vs 26.5 (13.8), p = 0.02). The group size effect was partially explained by a shorter latency to begin eating, a faster eating rate and reduced social interaction in larger groups. CONCLUSIONS: Children consumed 30% more food when eating in a group of nine children than when eating in a group of three children during longer snacks. Social facilitation of food consumption operates in preschool-aged children. The group size effect merits consideration in creating eating behaviour interventions. 相似文献
88.
Volumetric rendering of MR images 总被引:1,自引:0,他引:1
The authors developed new techniques for three-dimensional display of magnetic resonance (MR) images that preserve soft-tissue definition, are fully automatic, and work with routinely used section thicknesses. MR images are segmented, selectively enhanced, and displayed by means of a volumetric rendering algorithm. These techniques were used to illustrate normal anatomy of the brain, knee, and liver. Three-dimensional rendering of balanced spin-echo images shows the ventricles and extracerebral veins and of T1-weighted images, the sulci and gyri. The large hepatic and portal vessels can be seen with these enhancement techniques. Three-dimensional views of the knee reveal articular surfaces of the tibia and clearly depict menisci and posterior and anterior cruciate ligaments. These techniques make it possible to image multiple soft tissues simultaneously while preserving the detail contained in the original images. Three-dimensional presentation of complex, overlapping anatomic regions is helpful in surgical planning and should lead to improved diagnosis. 相似文献
89.
Hasegawa BH; Naimuddin S; Dobbins JT d; Mistretta CA; Peppler WW; Hangiandreou NJ; Cusma JT; McDermott JC; Kudva BV; Melbye KM 《Radiology》1986,159(2):537-543
The feasibility of producing patient-specific beam attenuators for chest radiography has been investigated using an anthropomorphic phantom and a human volunteer. A low-dose test exposure is digitized, processed, and used to print a small cerium filter, which is placed in the x-ray beam near the collimator. The final radiograph is recorded on film. The technique results in relatively uniform film exposure, so that structures in all regions of the chest are simultaneously displayed with optimal film contrast. The equalized exposure improves image quality in the normally underpenetrated regions and reduces the role of cross-scatter from the lungs. The image is analogous to optical or computer-processed unsharp masking techniques, but the processing is accomplished in the x-ray beam and results in an improved exposure distribution, giving advantages that cannot be achieved with image processing techniques alone. 相似文献
90.
JC Szepietowski† J Salomon† P Pacan‡ E Hrehorów† A Zalewska§ 《Journal of the European Academy of Dermatology and Venereology》2008,22(7):795-799
The aim of this study was to determine the frequency of body dysmorphic disorder (BDD) identified by Polish dermatologists and to evaluate the treatment modalities applied by them.
Methods A specially designed questionnaire was distributed to 172 dermatologists. A total of 118 doctors responded (68.6%). The dermatologists were asked regarding demographic data, frequency of BDD in their everyday practice and methods of treatment they used in managing BDD patients.
Results During the whole working period, over the half of dermatologists (64%) had observed at least one BDD patient in their practice. One fifth (20%) of the respondents observed 1 or 2 BDD cases during the past 5 years, 14% observed 3 to 5 such patients, 7% observed 5 to 10 BDD cases, and 5% of the doctors reported seeing more than 10 BDD patients within this period. Almost 18% of dermatologists were currently treating a BDD patient. Our data show that 40.7% of the respondents always ask and 28.8% often ask for a psychiatric opinion. More experienced dermatologists statistically more frequently ( P < 0.05) obtained a psychiatric opinion about their patients. Only a small group of dermatologists (15.3%) use their own pharmacological treatment. If they do so, they first use anxiety-relieving drugs and placebo.
Conclusion BDD is a quite common disorder; however, not all dermatologists are sufficiently prepared to treat it. There is an urgent need for training of dermatologists on the effective approach to psychodermatoses. 相似文献
Methods A specially designed questionnaire was distributed to 172 dermatologists. A total of 118 doctors responded (68.6%). The dermatologists were asked regarding demographic data, frequency of BDD in their everyday practice and methods of treatment they used in managing BDD patients.
Results During the whole working period, over the half of dermatologists (64%) had observed at least one BDD patient in their practice. One fifth (20%) of the respondents observed 1 or 2 BDD cases during the past 5 years, 14% observed 3 to 5 such patients, 7% observed 5 to 10 BDD cases, and 5% of the doctors reported seeing more than 10 BDD patients within this period. Almost 18% of dermatologists were currently treating a BDD patient. Our data show that 40.7% of the respondents always ask and 28.8% often ask for a psychiatric opinion. More experienced dermatologists statistically more frequently ( P < 0.05) obtained a psychiatric opinion about their patients. Only a small group of dermatologists (15.3%) use their own pharmacological treatment. If they do so, they first use anxiety-relieving drugs and placebo.
Conclusion BDD is a quite common disorder; however, not all dermatologists are sufficiently prepared to treat it. There is an urgent need for training of dermatologists on the effective approach to psychodermatoses. 相似文献