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排序方式: 共有946条查询结果,搜索用时 31 毫秒
1.
Magnetic resonance imaging and clinical correlates of intellectual impairment in myotonic dystrophy 总被引:4,自引:0,他引:4
S J Huber J T Kissel E C Shuttleworth D W Chakeres L E Clapp M A Brogan 《Archives of neurology》1989,46(5):536-540
Although intellectual impairment is common in patients with myotonic dystrophy, this aspect of the disease has received relatively little research attention. We examined 41 patients with myotonic dystrophy using objective neuropsychological procedures and magnetic resonance imaging. Ten patients (24%) had severe and generalized intellectual dysfunction, while lesser or no cognitive impairment characterized the remaining patients. Degree of intellectual impairment was not related to neuromuscular status or sex. Patients with severe intellectual disturbance had significantly earlier onset of both myotonia and weakness and were more likely to inherit the disease from their mother. Magnetic resonance imaging findings indicated that while degree of cerebral atrophy was not related to severity of intellectual impairment, skull thickness, focal white matter lesions, and anterior temporal lobe abnormalities were significantly more common in patients with severely disturbed intellect. This study reports a number of previously unreported cerebral magnetic resonance imaging findings associated with intellectual impairment in myotonic dystrophy, but the etiology of these changes awaits neuropathologic examination. 相似文献
2.
Golli M; Van Nhieu JT; Mathieu D; Zafrani ES; Cherqui D; Dhumeaux D; Vasile N; Rahmouni A 《Radiology》1994,190(3):741
3.
G. Fricker J. Drewe J. Vonderscher T. Kissel C. Beglinger 《British journal of pharmacology》1992,105(4):783-786
1. The somatostatin octapeptide-analogue, octreotide, is absorbed as intact peptide from the gastrointestinal (GI) tract. 2. In situ absorption experiments in rats confirmed our recent intubation studies in human volunteers demonstrating that the peptide has preferential absorption sites in the small intestine. Absorption of octreotide was higher in the jejunum than in the duodenum or the ileum. 3. Experiments with bile-duct cannulated rats demonstrated that the absorption of octreotide decreased in the presence of bile, reflecting a negative influence of biliary components on the absorption of the peptide. 4. Uptake experiments using rat jejunal brush border membranes were performed to analyse the absorption mechanisms. The transport of octreotide into jejunal brush border membranes was significantly higher than the uptake into membrane vesicles isolated from rat ileum. When initial uptake (0-15s) rates into the membrane vesicles were calculated as a function of the peptide concentration, a saturable component could be observed, indicative of transport mechanisms different from simple diffusion. 相似文献
4.
5.
At birth the human newborn is immature and has not yet acquired fully competent organ functions. During lactation especially the digestive tract and the immune system gain competence. Lactation is regulated by a complex interaction of numerous hormonal factors. Most important are probably prolactin and oxytocin—two hormones produced and secreted in the pituitary. The production and secretion of these two hormones is again regulated by several factors in the central nervous system and these mechanisms can be disturbed by a variety of exogenous factors such as drugs and any other substances interacting with dopamine metabolism in the brain. It is important to know these physiological interactions to be able to understand the regulation of lactation and to be able to assess which factors could interfere with this process. 相似文献
6.
MGC Hendriks P Dogterom JT Ebels B Oosterhuis LR Geertsema T Hulot G Bianchetti and JHG Jonkman 《Fundamental & clinical pharmacology》1998,12(5):559-565
Summary— In the present study we have compared the steady state biopharmaceutic characteristics of four diltiazem once daily controlled release capsules: Mono-Tildiem LP 300® (300 mg), Adizem® XL (300 mg)1, Cardizem® (300 mg) and Dilacor® (240 mg). Sixteen healthy male volunteers (aged 22.9 ± 3.3 years, range 19–31 years) completed an open label, multiple oral dose, randomized, four-period crossover study without a washout period in between. The volunteers received each diltiazem formulation once daily for four days. Trough diltiazem and metabolites plasma concentrations were determined on days 3 and 4. The 24-h plasma concentration-time profiles were assessed after the dose on day 4 of each period. The following steady state pharmacokinetic parameters for diltiazem were calculated: the minimum plasma concentration (cmin), the maximum plasma concentration (cmax), the time to reach that concentration (tmax), the time interval during which the plasma concentration exceeds 50% of cmax (t50), the area under the plasma concentration-time curve (AUC72–96) and the peak-to-trough fluctuation (PTF). For the metabolites of diltiazem, N-mono-desmethyl-diltiazem (NDM) and desacetyldiltiazem (DAD), AUC72–96 (AUCNDM and AUCDAD) and the ratio metabolite/parent compound were calculated. Steady state was achieved on day 3. Except one, all controlled release formulations have satisfactory controlled release properties allowing once daily administration. However, significant (P < 0.05) differences were found between the pharmacokinetic characteristics which do not allow exchange of the various formulations. Concentrations well below 50 ng·mL-1 in the morning hours were observed for Dilacor® (240 mg) and Adizem® XL (300 mg), which could be a disadvantage of these formulations as it is well-known that ischaemic events occur at a higher rate during that part of the day. The plasma concentration profiles of NDM and DAD, the major circulating metabolites, parallel the plasma concentration profiles for the parent compound. From a clinical point of view, all treatments were well tolerated. 相似文献
7.
Intestinal obstruction proximal to a transition zone without an interposed physical barrier usually indicates Hirschsprung disease. The authors report one case of focal small bowel muscular thinning just distal to a transition zone that produced clinical and radiographic findings that simulated long-segment Hirschsprung disease in a 2-day-old infant. 相似文献
8.
Development of hatching blastocysts from immature human oocytes following in-vitro maturation and fertilization using a co-culture system 总被引:8,自引:0,他引:8
Hwu YM; Lee RK; Chen CP; Su JT; Chen YW; Lin SP 《Human reproduction (Oxford, England)》1998,13(7):1916-1921
Recently, in-vitro maturation (IVM) of immature human oocytes recovered
from non-stimulated follicles has been applied in the treatment of
infertility. However, in previous reports, very few embryos cultured in
conventional medium have reached the expanded blastocyst stage following
in-vitro maturation and fertilization (IVM/IVF). The objective of this
study was to investigate whether the developmental competence of human
embryos following IVM/IVF could be enhanced by the use of a human ampullary
cell co-culture system. Immature human oocytes were aspirated from small
follicles at Caesarean section and then cultured in medium containing human
menopausal gonadotrophin for 36 to 48 h, followed by insemination. Zygotes
were randomly cultured either in conventional culture medium alone or in
the co-culture system. Of 48 embryos cultured in conventional medium alone,
all arrested at the 2-16- cell stage on day 3 after insemination. Of 46
embryos cultured in the co-culture system, 26 embryos (56.5%) arrested at
the 2-16-cell stage. Six embryos (13%) developed to the morula stage.
Fourteen embryos (30.4%) developed to expanded blastocysts and two
blastocysts were hatching on day 7 after insemination. We conclude that
co-culture significantly enhances the development of blastocysts in embryos
resulting from IVM/IVF.
相似文献
9.
Salmonella-specific monoclonal antibodies against recombinant Salmonella typhi 36-kilodalton porin. 下载免费PDF全文
V Kissel C Gonzalez M Astudillo A Godard B Wachman F C Cabello 《Clinical and Vaccine Immunology : CVI》1994,1(2):250-252
Mouse monoclonal antibodies were raised against recombinant Salmonella typhi 36-kDa porin monomer. Specificities of 16 monoclonal antibodies were analyzed as reactivity patterns in dot immunobinding and Western blot (immunoblot) assays using isolated outer membrane proteins of gram-negative bacteria and cloned purified S. typhi porin monomers and trimers. Four monoclonal antibodies were specific for Salmonella spp. 相似文献
10.
The ratio of 2nd to 4th digit length: a predictor of sperm numbers and concentrations of testosterone, luteinizing hormone and oestrogen 总被引:19,自引:2,他引:19
Manning JT; Scutt D; Wilson J; Lewis-Jones DI 《Human reproduction (Oxford, England)》1998,13(11):3000-3004
The differentiation of the urinogenital system and the appendicular
skeleton in vertebrates is under the control of Hox genes. The common
control of digit and gonad differentiation raises the possibility that
patterns of digit formation may relate to spermatogenesis and hormonal
concentrations. This work was concerned with the ratio between the length
of the 2nd and 4th digit (2D:4D) in humans. We showed that (i) 2D:4D in
right and left hands has a sexually dimorphic pattern; in males mean 2D:4D
= 0.98, i.e. the 4th digit tended to be longer than the 2nd and in females
mean 2D:4D = 1.00, i.e. the 2nd and 4th digits tended to be of equal
length. The dimorphism is present from at least age 2 years and 2D:4D is
probably established in utero; (ii) high 2D:4D ratio in right hands was
associated with germ cell failure in men (P = 0.04); (iii) sperm number was
negatively related to 2D:4D in the right hand (P = 0.004); (iv) in men
testosterone concentrations were negatively related to right hand 2D:4D and
in women and men LH (right hand), oestrogen (right and left hands) and
prolactin (right hand) concentrations were positively correlated with 2D:4D
ratio and (v) 2D:4D ratio in right hands remained positively related to
luteinizing hormone and oestrogen after controlling for sex, age, height
and weight.
相似文献