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排序方式: 共有1154条查询结果,搜索用时 15 毫秒
1.
HJ Aubin S Tilikete C Laureaux HT Nguyen Hac MC Roullet-Volmi S Troupel D Barrucand 《European psychiatry》1995,10(8)
The aim of this study was to assess alcoholic inpatients' smoking and coffee intake variation following withdrawal. Only moderate smokers (less than 30 cigarettes/day) showed a significant increase of cigarette consumption after alcohol withdrawal. However, their urinary cotinine level did not vary, suggesting a behavioral, and not biological, compensation through smoking following alcohol withdrawal. Heavy smokers (30 cigarettes/day or more) showed no significant clinical or biological variation of smoking behavior. Coffee consumption increased after alcohol withdrawal in all patients, irrespective of smoking habits. 相似文献
2.
J. G. Boonstra Johan W. van der Pijl Yves F. C. Smets Herman H. P. J. Lemkes Jan Ringers Leendert A. van Es F. J. van der Woude Jan A. Bruijn 《Transplant international》1997,10(6):451-456
To examine the incidence of interstitial and vascular
rejection in pancreas allografts and its impact on graft survival, we studied 36 percutaneous pancreas biopsies and 10 pancreas
transplantectomy specimens from 32 patients who had undergone simultaneous pancreas-kidney transplantation. Interstitial rejection
(IR) was predominantly found in the biopsies, while vascular rejection (VR) was most prominent in the transplantectomies.
Pancreas graft survival was significantly decreased for pancreas grafts that had suffered from vascular rejection when compared
to those with only interstitial rejection. Potential rejection markers, i. e., serum amylase, glucose, creatinine, and urinary
amylase, did not correlate with histological signs of rejection, although increased levels of serum amylase were, in all but
one case, associated with rejection.We conclude that a percutaneous pancreas biopsy remains the most reliable method to determine
pancreas rejection, and that by distinguishing between IR andVR, a pancreas biopsy may provide important diagnostic as well
as prognostic information.
Received: 6 March 1997 Received after revision: 5 June 1997 Accepted: 30 June 1997 相似文献
3.
Rene C. Bakker Eduard M. Scholten Johan W. de Fijter Leendert C. Paul 《Transplantation reviews (Orlando, Fla.)》2004,18(1):54-64
Although extensively studied, the pathophysiologic characteristics of chronic cyclosporine (CsA) nephrotoxicity are still far from being completely understood. The recognition of chronic CsA nephrotoxicity in allografted kidneys is hampered by a lack of easily assessable sensitive and specific markers. Long-term results of CsA withdrawal trials and trials that evaluated CsA sparing or withdrawal after the diagnosis of chronic allograft nephropathy (CAN) have shown that chronic CsA nephrotoxicity has a more important role in the etiology of late transplant dysfunction than appreciated before. Various hypotheses have explained the renal structural changes of chronic CsA nephrotoxicity including ischemia, cellular toxicity, and the stimulation of renal fibrosis by growth factors or cytokines. Possible ways to prevent chronic CsA nephrotoxicity include improved therapeutic drug monitoring and CsA withdrawal or avoidance. Patients with aspecific CAN in late biopsy may benefit from withdrawal of CsA or a reduction of its dose. Current knowledge is being discussed. It is concluded that in the near future more strategies are likely to be used to prevent loss of allograft function as a result of drug toxicity. 相似文献
4.
BACKGROUND: A simple, rapid, inexpensive method for measuring the flow in a
patient's vascular access would permit routine monitoring during
haemodialysis, and hence provide information of access graft deterioration
sufficiently early to increase the success of minimally invasive remedial
procedures. This paper reports the validation of such a method in animals.
METHODS: A PTFE graft was implanted in sheep between the carotid artery and
the jugular vein. While the sheep was under general anaesthesia and on an
haemodialysis circuit, ultrasound velocity in its blood was perturbed by
the injection of a 5-10 ml bolus of isotonic NaCl. The pump tubing flow was
measured by a transit-time blood flow meter. This flow was combined with
the areas of perturbation generated by the injection before and after
mixing in the access flow to estimate graft flow. The calculated graft flow
was compared to flow measured directly by a transit-time probe on the same
carotid artery. RESULTS: Over a 10-fold range, 120-1260 ml/min, graft flow
measured by ultrasound velocity dilution agreed well with graft flow
measured directly with a scatter of 76 ml/min about the regression line.
CONCLUSION: Ultrasound velocity dilution provides a method for measuring
flow in the graft accurate enough for clinical evaluation of patients on
dialysis.
相似文献
5.
Gino Kerkhoffs Leendert Blankevoort Idsart Kingma Niek van Dijk 《Knee surgery, sports traumatology, arthroscopy》2007,15(6):817-824
Questions addressed in this in-vitro study are (1) what are the actual three-dimensional kinematics of talus and calcaneus during an anterior drawer test as performed with the quasi-static anterior ankle tester (QAAT) (2) does laxity measurement with the QAAT represent the true anterior translation of talus relative to the tibia?. Simultaneous measurements were made with the QAAT and a three-dimensional kinematics analysis system in five specimens. The three-dimensional translations and rotations on three axes were analysed at 25, 50 and 100 N of applied anterior load, with increased ligament damage. For four out of five remaining specimens, anterior translation values of talus and calcaneus and values as measured with the QAAT show a significant increase with growing ligament damage and with higher loads. Skeletal motions of talus and calcaneus show great similarity in three different motion axes, with increased ligament damage and at any given load. Skeletal translations and rotations of talus and calcaneus show great similarity during an anterior drawer movement of the ankle joint. Anterior skeletal translation of the talus and calcaneus show fair correlation with the anterior displacements measurements of the QAAT. These QAAT measurements show an overestimation of the laxity value by more than 200% irrespective of the load applied. 相似文献
6.
Antibody Response Against the Glomerular Basement Membrane Protein Agrin in Patients with Transplant Glomerulopathy 总被引:3,自引:0,他引:3
Simone A. Joosten Yvo W.J. Sijpkens Vanessa van Ham Leendert A. Trouw Johan van der Vlag Bert van den Heuvel Cees van Kooten Leendert C. Paul 《American journal of transplantation》2005,5(2):383-393
Chronic allograft nephropathy (CAN) of renal allografts is still the most important cause of graft loss. A subset of these patients have transplant glomerulopathy (TGP), characterized by glomerular basement membrane (GBM) duplications, but of unknown etiology. Recently, a role for the immune system in the pathogenesis of TGP has been suggested. In 11 of 16 patients with TGP and in 3 of 16 controls with CAN in the absence of TGP we demonstrate circulating antibodies reactive with GBM isolates. The presence of anti-GBM antibodies was associated with the number of rejection episodes prior to diagnosis of TGP. Sera from the TGP patients also reacted with highly purified GBM heparan sulphate proteoglycans (HSPG). Indirect immunofluorescence with patient IgG showed a GBM-like staining pattern and colocalization with the HSPGs perlecan and especially agrin. Using patient IgG, we affinity purified the antigen and identified it as agrin. Reactivity with agrin was found in 7 of 16 (44%) of patients with TGP and in 7 of 11 (64%) patients with anti-GBM reactivity. In conclusion, we have identified a humoral response against the GBM-HSPG agrin in patients with TGP, which may play a role in the pathogenesis of TGP. 相似文献
7.
M Kaplan HJ Vreman C Hammerman C Leiter B Rudensky MG MacDonald DK Stevenson 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(4):455-457
The incidence (%) of hyperbilirubinemia (serum bilirubin ≥257 μmol/l) was similar in neonates with a combination of ABO incompatibility and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency (45%), with ABO incompatibility (54%) or G-6-PD deficiency (37%), alone (ns). Carboxyhemoglobin values, corrected for inspired CO, were similarly elevated in all three groups (0.87 ± 0.32%, 0.82 ± 0.29%, 0.76 ± 0.18%, respectively, ns), but correlated with bilirubin only in those with ABO incompatibility alone. ABO-incompatible/G-6-PD-deficient neonates, compared with those with either condition alone, are not at increased risk for hemolysis or hyperbilirubinemia. 相似文献
8.
The effects of co-culture with human fibroblasts on human embryo development in vitro and implantation 总被引:5,自引:0,他引:5
Wetzels AM; Bastiaans BA; Hendriks JC; Goverde HJ; Punt-van der Zalm AP; Verbeet JG; Braat DD 《Human reproduction (Oxford, England)》1998,13(5):1325-1330
In a human in-vitro fertilization (IVF) programme, the effect of co-
culture of embryos with human fibroblasts was evaluated with respect to
pregnancy rate and embryo development. Patients were included in the study
after giving informed written consent. The IVF treatments were randomly
assigned by stratification of both age (<36 versus > or =36 years)
and previous IVF attempts (yes versus no). After fertilization was
established, the zygotes were transferred to a 4-well dish with or without
fibroblasts and cultured for 2 days. On the third day after ovum pick-up
(OPU), cell number and quality [5 (good) to 1 (poor)] of the embryos were
scored and a maximum of three embryos was transferred. Supernumerary
embryos of good quality were cryopreserved. The design of this study was a
group sequential trial with the objective of detecting differences between
pregnancy rates following IVF with conventional incubation or incubation in
co-culture with fibroblasts. This design included one evaluation at
half-way data collection. In the study, 148 patients had an OPU, of whom 77
were allocated to the co-culture group. There was no statistically
significant difference in pregnancy rate, cell number and embryo quality
between the two groups. The ongoing pregnancy rate per embryo transfer was
27% in co-culture and 30% in the conventional culture group. The
implantation rates per transferred embryo were 17 and 18% respectively.
Using a multivariate logistic regression model for the probability of
ongoing pregnancies, the odds ratio of co-culture, adjusted for age and
previous IVF attempts, was not statistically significant. In conclusion,
co-culture with human fibroblasts does not contribute to an improvement of
embryo quality nor to a higher pregnancy rate after IVF in an unselected
group of patients.
相似文献
9.
Honecker F Kersemaekers AM Molier M Van Weeren PC Stoop H De Krijger RR Wolffenbuttel KP Oosterhuis W Bokemeyer C Looijenga LH 《The Journal of pathology》2004,204(2):167-174
Intercellular contacts, mediated by E-cadherin, are essential for germ cell migration and maturation. Furthermore, it has been suggested that decrease or loss of E-cadherin correlates with tumour progression and invasive behaviour. beta-catenin is involved in a number of different processes, including cell--cell interaction when bound to cadherins, and determination of cell fate in pluripotent cells when activated via the Wnt signal-transduction pathway. To shed more light on the role of these factors in normal fetal germ cell development and the pathogenesis of germ cell tumours (GCTs), the present study investigated the presence and localization of E-cadherin and beta-catenin by immunohistochemistry. E-cadherin was only weakly expressed in or absent from fetal germ cells of the second and third trimesters, and was not expressed in carcinoma in situ/intratubular germ cell neoplasia unclassified (CIS/ITGCNU) and gonadoblastoma, the precursor of an invasive GCT in dysgenetic gonads. In GCTs, it was generally not expressed in seminoma and dysgerminoma, but was found in the vast majority of non-seminoma cells. beta-catenin was found in the cytoplasm of fetal germ cells at all gestational ages and in spermatogenesis in post-pubertal testes. It was also present in CIS/ITGCNU and gonadoblastoma. Whereas seminomas and dysgerminoma were negative, non-seminoma cells were frequently found to express beta-catenin. Expression of both factors therefore reflects the degree of differentiation of these tumours. No differences for either E-cadherin or beta-catenin were observed between samples of tumours resistant or sensitive to chemotherapy, and E-cadherin expression did not correlate with vascular invasion. E-cadherin and beta-catenin therefore play a role in both normal and malignant germ cell development and differentiation that warrants further investigation, but they seem to be of limited value as predictive or prognostic factors in GCTs. 相似文献
10.
Endothelin receptor expression in human decidua 总被引:3,自引:1,他引:3
Kohnen G; Campbell S; Irvine GA; Church HJ; MacLachlan F; Titterington M; Cameron IT 《Molecular human reproduction》1998,4(2):185-193
The endothelins are signalling peptides that act via two receptors, ET(A)
and ET(B). In the human endometrium, endothelin receptors have been
demonstrated in glands and stroma and have been shown to vary during the
course of the menstrual cycle. The present study was undertaken to
determine whether or not expression of endothelin receptors changes during
pregnancy or after administration of exogenous progestagens. The expression
of the receptors was correlated with the appearance of basement membrane
components during decidualization of the endometrial stroma. Decidual
specimens (n = 15) were obtained during the first trimester of pregnancy
and 10 at term. Sixteen pairs of endometrial biopsies were obtained from
women with menorrhagia before and after exposure to exogenous progestagens.
A total of 15 hysterectomy specimens were used as controls for the
expression of stromal basement membrane proteins in the absence of
decidualization. Autoradiography was carried out with selective ligands for
ET(A) ([125I]-PD 151242) and ET(B) ([125I]-BQ3020). The distribution of
ligand binding was then compared with the distribution of laminin alpha2
light chain and collagen IV. ET(A), ET(B), laminin alpha2 light chain, and
collagen IV were expressed in stromal decidual cells in the first trimester
of pregnancy. ET(B) was also found on endometrial glandular epithelium.
Quantitative macro-autoradiography and multiple regression analysis
demonstrated a highly significant positive correlation (P < 0.001)
between expression of ET(B) and laminin alpha2 light chain. In the third
trimester qualitative examination suggested a reduction of ET(A) in the
stroma. Progestagen-induced decidua exhibited a similar pattern to that
found in first trimester decidua. This study has demonstrated up-regulation
of ET(B) during the progesterone- dependent process of decidualization and
suggests a paracrine or autocrine role for endothelins in the decidua.
相似文献