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排序方式: 共有881条查询结果,搜索用时 15 毫秒
1.
Accuracy of an anthropometric estimate of the muscle and bone area in a transversal cross-section of the arm 总被引:3,自引:0,他引:3
F L de Koning R A Binkhorst J M Kauer H O Thijssen 《International journal of sports medicine》1986,7(5):246-249
To standardize the maximal static force (Fo) of the arm flexors, the accuracy of an anthropometric method for estimating the mid-arm cross-sectional muscle and bone area (MBA) was investigated. This was done by comparing the anthropometrically determined area (MBA.A) with the area measured by means of computerized tomography (MBA.S). In the same way, the accuracy of Heymsfield's equations (Heymsfield et al., 1982) for predicting MBA (MBA.H) from anthropometric measures was tested. MBA.A was significantly larger than MBA.S, the relative difference increasing with the thickness of the subcutaneous fat layer. This difference was attributed to a 27% underestimation of the fat layer thickness as measured with the skinfold caliper. Women being fatter than men, this caused the standardized maximal static force (Fo/MBA) to be lower in women than in men. MBA.H was 12% smaller than MBA.S. This may have been due to a difference in the way of measuring the arm circumference between the present authors and Heymsfield et al. 相似文献
2.
Renal selective N-acetyl-L-gamma-glutamyl prodrugs: studies on the selectivity of some model prodrugs. 总被引:2,自引:1,他引:1
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J. C. Drieman H. H. Thijssen H. A. Struyker-Boudier 《British journal of pharmacology》1993,108(1):204-208
1. In this study, a number of structurally different N-acetyl-L-gamma-glutamyl prodrugs were investigated with respect to selective uptake by the kidney in male Wistar rats. 2. All prodrugs were tested in vitro in rat kidney slices and kidney homogenate to study their uptake and conversion. It was found that the prodrugs of para-nitroaniline (agPNA), aminophenyl acetic acid (agAFA), sulphamethoxazole (agSM), sulphadimethoxine (agSDM), propranolol (agPP) and metoprolol (agMP) were accumulated by a probenecid-sensitive carrier. The prodrug of 4'-aminoantipyrine (agAAP) was not accumulated by a probenecid- or buthionine sulphoximine-sensitive carrier. Unlike all other prodrugs, agAAP and agMP were not, or only a very limited extent converted to the parent compound in vitro. 3. agPNA, agAFA and agPP were also investigated in vivo. The tissue distribution of the prodrugs and the parent drugs was established, as was their urinary excretion and pharmacokinetic behaviour. agPNA and agAFA showed selective uptake by the kidney, in contrast to agPP which accumulated in the liver. The distribution of the parent compounds following prodrug administration was as follows: agPNA was found in kidney and plasma: agAFA in kidney only; agPP in liver only. 4. The factors which determine the selectivity of N-acetyl-L-gamma-glutamyl prodrugs are discussed. The main factors are: the transport into the kidney, the conversion rate, the residence time of the prodrug in the kidney and the presence or absence of competition for uptake and conversation by other tissues, e.g. the liver.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
3.
P. M. J. Zelissen H. P. F. Koppeschaar D. W. Erkelens J. H. H. Thijssen 《Clinical endocrinology》1991,35(4):369-372
OBJECTIVE: To test the hypothesis that the hyperendorphinaemia in obesity originates from outside the pituitary. DESIGN: Intravenous administration of corticotrophin-releasing hormone (CRH) after overnight suppression with 2 mg of dexamethasone in normal-weight controls and in obese subjects before and after weight reduction. PATIENTS: Eleven obese females, age (mean +/- SEM) 30 +/- 2.1 years, body mass index (BMI) 41.2 +/- 1.9 kg/m2. Eight normal-weight females served as controls, age 26 +/- 2.1 years, BMI 21.4 +/- 0.5 kg/m2. Five obese subjects were also studied after weight loss of 18.4 +/- 1.0% of original weight. MEASUREMENTS: Plasma beta-endorphin, ACTH and cortisol. Cortisol production rate in 24-hour urine. Basal (without dexamethasone suppression) plasma beta-endorphin levels. RESULTS: Basal (without dexamethasone suppression) beta-endorphin levels were 7.7 +/- 0.8 pmol/l in the obese and 3.8 +/- 0.5 pmol/l in the control subjects (P less than 0.005). The degree of suppression of beta-endorphin after dexamethasone was similar in the obese (23.2 +/- 3.7%) and in the control subjects (28.2 +/- 0.12%). Administration of CRH following dexamethasone suppression resulted in a small but significant increase of plasma beta-endorphin in both obese (from 1.55 +/- 0.12 to 2.32 +/- 0.28 pmol/l) and control subjects (from 0.98 +/- 0.24 to 1.69 +/- 0.33 pmol/l). The groups did not differ regarding this response, nor regarding the release of ACTH and cortisol after CRH. Cortisol production rate was higher (P less than 0.001) in the obese (68.7 +/- 3.3 mumol/24 h) than in the controls (40.0 +/- 3.0 mumol/24 h). No correlation between cortisol production rate and basal beta-endorphin levels was found. Weight loss appeared to have no influence on cortisol production rate, basal beta-endorphin levels, or on the responses to dexamethasone or CRH. CONCLUSIONS: Plasma beta-endorphin in obese subjects can be affected by manipulations of the hypothalamic-pituitary-adrenocortical axis; the hypothesis that the hyperendorphinaemia of obesity originates from outside the pituitary cannot be confirmed. 相似文献
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.
R J van Suylen P H Schoof E Bos O M Frohn-Mulder J C den Hollander R Herzberger-ten Cate H J Thijssen 《European journal of cardio-thoracic surgery》1992,6(10):571-572
We report a 12-year-old girl suffering from juvenile rheumatoid arthritis with severe aortic valve incompetence who died 5 months after an initially successful Ross procedure. Pulmonary autograft failure was a result of recurrence of aggressive valvulitis. 相似文献
6.
M A Blankenstein J Szymczak J Daroszewski A Milewicz J H Thijssen 《Gynecological endocrinology》1992,6(1):13-17
Breast cancer tissue is able to maintain the tissue estradiol level in spite of the massive decrease in plasma estradiol associated with menopause, whereas fatty tissue from breasts with malignancies more closely reflects the changes in plasma. In the present study estrone and estradiol levels in fatty tissues from different origins were compared to evaluate the capacity of distant fatty tissues to act as estrogen reservoirs. Abdominal fat was obtained from 25 premenopausal and 20 postmenopausal women who underwent surgery for non-oncological reasons. Estrone and estradiol levels in these tissues were compared to those in breast fatty tissue from breast cancer patients. Plasma estrogen levels were not different in the two groups. In both groups, median plasma estradiol levels dropped sharply with menopause (from 363 to 40 pmol/l in breast cancer patients; from 280 to 45 pmol/l in the non-oncological patients; p less than 0.002), whereas a significant decrease in plasma estrone was observed only in the breast cancer patients (from 238 to 140 pmol/l; p less than 0.02). In premenopausal women, median estrone and estradiol levels in breast fatty tissue (1135 and 375 fmol/g, respectively) and abdominal tissue (1390 and 470 fmol/g, respectively) were not different. In postmenopausal women, however, significantly higher estrone levels (663 vs. 508 fmol/g; p less than 0.01) and estradiol levels (245 vs. 187 fmol/g; p less than 0.02) were found in abdominal fatty tissue. In view of the absolute estrogen levels in breast and abdominal fatty tissue and in plasma, we conclude, however, that it is unlikely that remote fat contributes substantially to the maintenance of estrogen levels in breast cancer tissue. 相似文献
7.
Increased frequency of congenital chromosomal aberrations in female partners of couples undergoing intracytoplasmic sperm injection 总被引:3,自引:7,他引:3
van der Ven K; Peschka B; Montag M; Lange R; Schwanitz G; van der Ven HH 《Human reproduction (Oxford, England)》1998,13(1):48-54
We evaluated the frequency of congenital chromosomal aberrations in a
sample of 305 couples included in an intracytoplasmic sperm injection
(ICSI) programme. Twenty individuals (3.3%) with congenital chromosomal
abnormalities could be identified. The following types of abnormalities
were observed: reciprocal translocations (n = 7), Robertsonian
translocations (n = 3), inversions (n = 3), other structural aberrations (n
= 4) and sex chromosome aberrations (n = 3). The rate of chromosomally
abnormal males (10/305, 3.3%) lay within the expected range for patients
with reduced semen quality. Surprisingly, 50% (10/20) of all abnormal
karyotypes were contributed by the female partner of ICSI patients. These
data confirm the higher incidence of chromosomal aberrations in infertile
populations as compared with the baseline population risk. Additionally,
the data imply that in some cases of male factor infertility a hidden
female chromosomal factor may be present, which cannot be identified by
standard clinical evaluation. In conclusion, we recommend chromosomal
analysis in both partners of couples undergoing ICSI treatment.
相似文献
8.
Identification of a gene disrupted by a microdeletion in a patient with X-linked retinitis pigmentosa (XLRP) 总被引:2,自引:2,他引:2
Roepman R; Bauer D; Rosenberg T; van Duijnhoven G; van de Vosse E; Platzer M; Rosenthal A; Ropers HH; Cremers FP; Berger W 《Human molecular genetics》1996,5(6):827-833
The gene for the most frequent from of X-linked retinitis pigmentosa
(XLRP), RP3, has been assigned by genetic and physical mapping to a segment
of less than 1000 kbp, which is flanked by the marker DXS1110 and the
ornithine transcarbamylase (OTC) gene. In search of microdeletions, we have
screened the DNA of 30 unrelated patients with XLRP by employing a
representative set of YAC-derived DNA fragments that were generated by
restriction enzyme digestion and PCR amplification. In one of these
patients, a 6.4 kbp microdeletion was detected which was not present in the
DNA of 444 male controls. A cosmid contig spanning the deletion was
constructed and used to isolate cDNAs from retina-specific libraries. Exons
corresponding to these expressed sequences as well as other putative exons
were identified by sequencing more than 30 kbp of the critical region. So
far, no point mutations in these putative exon sequences have been
identified.
相似文献
9.
Positional cloning of the gene for X-linked retinitis pigmentosa 3: homology with the guanine-nucleotide-exchange factor RCC1 总被引:6,自引:7,他引:6
Roepman R; van Duijnhoven G; Rosenberg T; Pinckers AJ; Bleeker-Wagemakers LM; Bergen AA; Post J; Beck A; Reinhardt R; Ropers HH; Cremers FP; Berger W 《Human molecular genetics》1996,5(7):1035-1041
The gene for retinitis pigmentosa 3 (RP3), the most frequent form of X-
linked RP (XLRP), has been mapped previously to a chromosome interval of
less than 1000 kbp between the DXS1110 marker and the OTC locus at
Xp21.1-p11.4. Employing a novel technique, YAC Representation Hybridization
(YRH)', we have recently identified a small XLRP associated microdeletion
in this interval, as well as several putative exons including the 3' end of
a gene that was truncated by the deletion. cDNA library screening and
sequencing of a cosmid centromeric to the deletion has now enabled us to
identify numerous additional exons and to detect several point mutations in
patients with XLRP. The predicted gene product shows homology to RCC1, the
guanine-nucleotide- exchange factor (GEF) of the Ras-like GTPase Ran. Our
findings suggest that we have cloned the long-sought RP3 gene, and that it
may encode the GEF of a retina-specific GTP-binding protein.
相似文献
10.
J. M. Thijssen H. J. Ter Laak P. M. A. van Well 《Pflügers Archiv : European journal of physiology》1978,374(2):199-204
In order to elucidate the effects of angiotensin II on renal function, angiotensin II (AII; 1 ng/kg per min) and the AII antagonist 1-sar-8-ala-angiotensin II (AIIA; 200 ng/kg per min) were infused into the renal artery of anesthetized dogs (pentobarbital), on either a high (8 mmol/kg per day for seven days) or a low sodium intake (0.5 mmol/kg). In sodium replete dogs AII produced renal vasoconstriction with decreased RBF (–28%;P<0.001), but with less decrease of GFR (–14%;P<0.001), leading to an increase of FF (+19%;P<0.01),andantidiuresis(–39%;P<0.001); the antinatriuresis (–58%;P<0.001) exceeded the antidiuresis (P<0.001). RBF (–10%;P<0.001) was less pronounced (P<0.001) during AII in sodium deplete dogs, GFR remained unchanged, but FF increased to the same extent (+16%;P<0.05); diuresis and urinary electrolyte excretion were however not affected. AIIA did not affect RBF, GFR, FF, nor diuresis in sodium replete dogs suggesting that endogenous AII has no tonic influence on renal function in these conditions. In sodium deplete animals AIIA produced an 11% (P<0.001) increase of RBF, without changes of GFR; FF decreased by 12% (P<0.01), but diuresis, natriuresis and kaliuresis were not affected. 相似文献