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排序方式: 共有854条查询结果,搜索用时 343 毫秒
1.
Steven JY Wang Claire Cornick Jacqueline O'Dowd Michael A Cawthorne Jonathan R S Arch 《Lipids in health and disease》2007,6(1):2
Background
Mice that lack acyl CoA:diacylglycerol acyltransferase (Dgat1 -/- mice) are reported to have a reduced body fat content and improved glucose tolerance and insulin sensitivity. Studies so far have focussed on male null mice fed a high fat diet and there are few data on heterozygotes. We compared male and female Dgat1 -/-, Dgat1 +/- and Dgat1 +/+ C57Bl/6 mice fed on either standard chow or a high fat diet. 相似文献2.
The purpose of this study was to determine the degree of agreement among different frequencies of blood pressure measurements (FoM) in 24-hour ambulatory blood pressure monitoring (ABPM) in their ability to obtain useful clinical information. ABPM records were obtained with a Del Mar IV Avionics device from 49 hospitalised preeclamptic women with a FoM of 7 per hour (high-FoM). With these records, we simulated two sets of data as if measurements had been recorded at a rate of 1 measurement per hour (low-FoM) and of 2 per hour (medium-FoM). Diastolic blood pressure > 89 mmHg defined hypertension and > 109 mmHg, severe hypertension The median and 25th and 75th centiles for the differences in hypertensive rate detected (expressed as percentage points) between lowFoM vs. high-FoM was 0.00 (- 3.4-3.00) and between medium-FoM vs. high-FoM,- 1.04 (- 3.7-1.5). The agreement in the detection of severely affected patients was 85% (CI 95%: 74-96) between low-FoM and high-FoM and 87% (CI 95%: 77-98), between medium-FoM and high-FoM. Average blood pressure was similar in the three FoMs studied at day-time and night-time. We did not find any strong argument to perform ABPM at a high-FoM. Lower FoM are more comfortable for the patient and could reduce equipment deterioration, while providing equivalent information to that supplied by high-FoM. 相似文献
3.
4.
LEE JS IM HH JUNG Y JUNG IS JANG JY CHUN YK CHO YD KIM JO CHO JY KIM YS SHIM CS & KIM BS 《Neurogastroenterology and motility》2006,18(6):493-494
Background: Recent development of extracorporeal magnetic stimulation (ECMS) which uses current‐changing magnetic fields allows the induction of electrical stimulation in the desired deep tissue. Recent study showed the sacral nerve stimulation reduces corticoanal excitability that may play a functional role in anal continence mechanisms. Preliminary study shows that ECMS of sacral nerve can modify pelvic floor function and expel rectal balloon in patients with pelvic floor dyssynergia (PFD). Aims: To evaluate the effect of ECMS compared with biofeedback therapy (BF) in patients with PFD. Methods and Materials: Thirty‐eight patients who fulfilled Rome II criteria for PFD by colon transit time and anorectal function tests, were randomly treated with 8 sessions of ECMS (2/weeks; n = 19) at prone position or BF (2/weeks; n = 19) at sitting position. Stimulation parameters were set at 50–80% of maximum intensity, 10 and 50 Hz frequency, 3 s burst length with 3 and 6 s off using arm‐typed stimulator (BioCom‐1000, Mcube Co., Korea). Symptom scores for constipation with/without anorectal function test were repeatedly measured after each treatment. Response was defined as 50% or more decreased symptom score after treatment (partial response: 30–50%, poor: <30%). Results: Fifteen patients (age 49.1 ± 13.4 years, mean ± SD; 4 men) completed 8 session of BF and 14 patients (54.5 ± 17.6 years, 3 men) completed 8 session of ECMS. Four patients of BF group discontinued treatment due to unsatisfactory therapeutic effect (n = 1) and withdrew consent (n = 3) and 5 patients of ECMS group discontinued treatment because of same reasons (n = 1, 4). Total symptom scores were significantly decreased after treatment of 8 session in both treatment groups (13.4 ± 6.6 vs. 4.3 ± 4.0 for BF, p = 0.009; 14.9 ± 5.6 vs. 3.4 ± 4.0 for ECMS, p < 0.001). Bowel movements per week were also significantly increased after treatment in both groups (median 2 vs. 7 for BF, p = 0.035; median 2 vs. 7 for ECMS, p = 0.008). Thirteen out of 15 patients showed response in BF group and 12 out of 14 showed good response in ECMS group. No adverse effects in both groups. Conclusions: ECMS is as effective as BF for the treatment of PFD. Long‐term effect of ECMS for the patients with pelvic floor dyssynergia need to be evaluated in the near future. 相似文献
5.
Raoul JL; Bourguet P; Bretagne JF; Duvauferrier R; Coornaert S; Darnault P; Ramee A; Herry JY; Gastard J 《Radiology》1988,168(2):541-545
Biodistribution of iodine-131-labeled Lipiodol Ultra-Fluide (I-131 LUF) injected into the hepatic artery was studied scintigraphically in 47 patients with hepatocellular carcinoma (n = 23), hepatic metastases (n = 14), or normal livers (n = 10). The investigation was extremely well tolerated. I-131 LUF concentrated mainly in the liver (L) and the lungs (l), with L/L + l activity ratios greater than 75% for all three groups of patients. I-131 LUF distribution was homogeneous in normal livers and heterogeneous in cirrhotic livers. I-131 LUF concentrated in the tumor with a tumorous (T) to nontumorous (NT) activity ratio (T/NT) of 4.3 +/- 3.6 for hepatocellular carcinoma and 2.4 +/- 0.7 for hepatic metastases. The effective half-life of I-131 LUF is more than 4.5 days for the three groups. It was eliminated mainly through the urine. Clearance from tumor is slower than from normal liver, as shown by the increase in T/NT at day 18. Biodistribution did not change in patients who had a second injection, which indicates that there is no saturation phenomenon. The results of this study suggest that LUF may be considered as a potential carrier vehicle for therapeutic agents. 相似文献
6.
R Blok D H Margulies L Pease R K Ribaudo J Schneck J McCluskey 《International immunology》1992,4(4):455-466
The influence of CD8 on the fine specificity of MHC class I-restricted T cell allorecognition was evaluated by comparing the reactivity of CD8- and CD8-transfected forms of an allospecific, H-2Kb-restricted T hybridoma. The CD8- T hybridoma responded to cells expressing H-2Kb, H-2Kbm6, and the individual H-2Kb----bm10 back mutations 165V----M, 173K----E, and 174N----L. Under the same conditions the CD8- T hybridoma responded poorly or not at all to cells expressing H-2Kbm10, H-2Kbm8, the individual H-2Kb----bm10 back mutants 163T----A and 167W----S, and the individual H-2Kb----bm8 back mutations 22Y----F and 24E----S. In contrast, T hybridoma cells expressing high levels of CD8 reacted strongly with antigen presenting cells (APC) expressing H-2Kb and H-2Kbm6 molecules, as well as APC expressing H-2Kbm10 (weakly), H-2Kbm8, and all five individual H-2Kb----bm10 and the two H-2Kb----bm8 back mutants 22Y----F and 24E----S. The mutations which distinguish the T cell recognition of both H-2Kbm10 and H-2Kbm8 from H-2Kb are predicted to control the interaction of these class I molecules with antigenic peptides in the binding site, implying an important role for peptide antigen in T cell allorecognition. Nonetheless, CD8 expression by the H-2Kb-restricted T cells conferred novel or enhanced alloreactivity with cells expressing H-2Kbm10, H-2Kbm8, and each of the individual H-2Kb----bm10 and H-2Kb----bm8 back mutants. These findings reflect an important role for CD8 in influencing the fine specificity of MHC class I recognition by T cells and may indicate a limited structural role for peptide antigen in defining the ligand recognized by these alloreactive T cells. 相似文献
7.
A G Hohmann R R Matsumoto M K Hemstreet S L Patrick J E Margulies R P Hammer J M Walker 《Brain research》1992,593(2):265-273
The 2-deoxy-D-[1-14C]glucose ([14C]DG) method was used to examine the effects of the relatively selective sigma ligand 1,3-di-o-tolylguanidine (DTG) on cerebral metabolism in freely moving rats. Each animal received an i.p. injection of DTG (0.2, 1, or 5 mg/kg) or normal saline 20 min prior to the infusion of [14C]DG. DTG induced dose-dependent changes in local cerebral glucose utilization (LCGU) in several motor and limbic structures. Most structures showed increases in LCGU, with a maximum effect at 1 mg/kg. The most profound increases in LCGU were observed in brain regions that are rich in sigma receptors. These included cerebellar and related nuclei (interpositus, lateral and medial cerebellar n., vestibular n., olivary n.), ambiguus n., superior colliculus (superior layers), hippocampus (CA2, CA3, DG), n. basalis of Meynert interpeduncular n., and the substantia nigra pars compacta and pars reticulata. No significant decreases in glucose utilization were observed at any dose. Although the areas affected by DTG are similar to those previously reported for other sigma ligands, future studies employing a range of doses for additional selective sigma ligands must be carried out in order to confirm whether these changes in LCGU were sigma-mediated. 相似文献
8.
BACKGROUND: The recent introduction of urea sensors for dialysis monitoring
has made possible new approaches to urea kinetic modelling. In this study
we show how the equilibrated postdialysis urea concentration (Ceq) and Kt/V
corrected for double-pool urea kinetics (Kt/Vdp) can be accurately
determined using an on-line sensor providing a continuous measure of blood
water urea. A modification of the Smye constant volume double-pool theory
led to the following equations for Ceq and Kt/Vdp [formula: see text] where
Cpre is the blood concentration measured at the start of dialysis, t is the
length of the dialysis session (in min) and S(ex) is the constant slope of
the blood urea logarithm concentration decline following development of the
intercompartmental urea concentration gradient in the first 30-60 min of
dialysis. METHODS: These equations were tested in 11 patients undergoing
165-240 min of paired filtration dialysis with continuous monitoring of
blood urea concentration. Cpre was determined as the plateau concentration
during a preliminary period of 15-20 min of slow isolated ultrafiltration.
S(ex) was accurately determined from linear regression applied to the urea
sensor data from the 80-min point to the end of dialysis. RESULTS: Ceq and
Kt/Vdp determined from the above equations compared closely to values
determined from 25-40 min of urea rebound monitoring with the urea sensor:
10.6 +/- 3.0 versus 10.8 +/- 2.7 mmol/l (mean +/- SD) for Ceq and 1.21 +/-
0.24 versus 1.18 +/- 0.20 for Kt/Vdp, compared to single-pool values of
Kt/V = 1.34 +/- 0.23. CONCLUSION: This technique may be readily programmed
into on-line urea monitors to provide current and extrapolated values of
Ceq and Kt/Vdp from about the first hour of dialysis.
相似文献
9.
Darai E; Leblanc M; Walker-Combrouze F; Bringuier AF; Madelenat P; Scoazec JY 《Human reproduction (Oxford, England)》1998,13(5):1346-1352
We evaluated the immunohistochemical expression of cadherins and CD44
variants in 20 endometriomas, 20 cystadenomas, 20 borderline ovarian
tumours as well as 20 ovarian carcinomas, and the serological and cystic
fluid concentrations of soluble E-cadherin and soluble CD44 standard
(sCD44sdt) in 20 endometriomas, 20 cystadenomas, six borderline and 11
carcinomas of the ovary. In endometriomas, immunostaining of E- and
N-cadherin was negative (20 and 30% respectively). CD44 H, v3 and v6
immunostaining were detected in 63, 10 and 40% respectively. A difference
in immunostaining for E-cadherin was found between endometriomas and
cystadenomas (P < 0.001) and for N- cadherin between endometriomas and
carcinomas (P < 0.001). A difference in CD44H immunostaining was
observed between endometriomas and cystadenomas (P < 0.035) but not with
borderline ovarian tumours and carcinomas. No difference in serum
concentrations of soluble E- cadherins and CD44 standard was found between
the four groups of tumours. Cystic fluid concentrations of E-cadherin were
lower in endometriomas than in borderline tumours and ovarian carcinomas (P
< 0.001). High concentrations of soluble CD44 standard cystic fluid were
found in endometriomas than in other ovarian cysts. Endometriomas and
borderline tumours share alterations of cadherins and CD44 isoforms which
may help in the understanding of the aggressive and invasive potentials of
endometriotic cells.
相似文献
10.
Dam J Guan R Natarajan K Dimasi N Chlewicki LK Kranz DM Schuck P Margulies DH Mariuzza RA 《Nature immunology》2003,4(12):1213-1222
The Ly49 family of natural killer (NK) receptors regulates NK cell function by sensing major histocompatibility complex (MHC) class I. Ly49 receptors show complex patterns of MHC class I cross-reactivity and, in certain cases, peptide selectivity. To investigate whether specificity differences result from topological differences in MHC class I engagement, we determined the structure of the peptide-selective receptor Ly49C in complex with H-2K(b). The Ly49C homodimer binds two MHC class I molecules in symmetrical way, a mode distinct from that of Ly49A, which binds MHC class I asymmetrically. Ly49C does not directly contact the MHC-bound peptide. In addition, MHC crosslinking by Ly49C was demonstrated in solution. We propose a dynamic model for Ly49-MHC class I interactions involving conformational changes in the receptor, whereby variations in Ly49 dimerization mediate different MHC-binding modes. 相似文献