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排序方式: 共有931条查询结果,搜索用时 31 毫秒
1.
Petri Koivunen Niko Rantala Kalevi Hyrynkangas Kalevi Jokinen Olli-Pekka Alho 《European archives of oto-rhino-laryngology》2002,259(10):543-546
A population-based survey was conducted in northern Finland in order to study the incidence rate and survival in patients with pharyngeal cancer diagnosed between 1986 to 1996. A total of 95 new patients with hypopharyngeal, oropharyngeal or nasopharyngeal cancers were identified. The overall age-adjusted incidence rates (per 100,000 years) were 1.28 in men and 0.60 in women, giving an overall incidence rate of 0.89. Most of the tumours were diagnosed at stage IV, and the median disease-specific survival times were 27.6 months for the patients with oropharyngeal cancer, 13.5 months for nasopharyngeal cancer and 17.7 for hypopharyngeal cancer. The most important factors that were associated with a poor prognosis were stage IV in oropharyngeal [Hazard ratio (HR) 3.68, 95% confidence interval (CI) 0.97-13.92] and hypopharyngeal cancer (HR 3.99, CI 1.51-10.67) and age over 65 years in nasopharyngeal cancer (HR 9.28, CI 1.79-47.99). 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.
4.
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
5.
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
6.
The NTP has a long history of using Fischer rats and has compiled a large database of incidences of lesions seen in control animals. Such a database is lacking for Harlan Sprague-Dawley (SD) rats. The intention of this paper is to report spontaneous lesions observed in female vehicle control Harlan SD rats, and to compare the incidence in 2 strains of rats (Fischer and Harlan SD) used in NTP studies. Female Harlan SD rats served as the test animals for a special series of 2-year studies. Male rats were not used in these studies. Complete histopathology was performed on all animals, and the pathology results underwent comprehensive NTP pathology peer review. The most commonly observed neoplasms in these female control Harlan SD rats were mammary gland fibroadenoma (71%), tumors of the pars distalis of the pituitary (41%) and thyroid gland C-cell tumors (30%). Female Fischer rats had incidences of 44% for mammary gland fibroadenomas, 34% for tumors of the pars distalis, and 16% for thyroid gland C-cell tumors. Fischer rats had a 15% incidence of clitoral gland tumors, while the Harlan SD rats had an incidence of < 1%. In contrast to Fischer F344 rats, the Harlan SD rats had a high incidence of squamous metaplasia of the uterus (44.2%). Squamous metaplasia is not a lesion commonly observed in NTP control Fischer rats. The Harlan SD rats had a very low incidence of mononuclear cell leukemia (0.5%), compared with an incidence of 24% in female Fischer rats. 相似文献
7.
Anne Jokinen Pekka Santtila Niklas Ravaja Sampsa Puttonen 《International journal of psychophysiology》2006,62(1):175-184
Guilty Knowledge Test measuring electrodermal reactions was carried out in order to investigate the quality of different questions and the validity of the test in a situation that resembled a true crime. Fifty participants were randomly assigned to commit one of two realistic mock crimes, and were later tested with GKTs concerning both the crime they had enacted and the one they had no knowledge of. Different scoring systems (SCRs and peak amplitudes as well as raw and standardised scores) were employed and compared when analyzing the results. Although there were some false positives, the test was able to differentiate between the groups of guilty and innocent participants. With the best scoring systems, the test was able to classify up to 84% of the innocent and up to 76% of the guilty correctly according to a logistic regression analysis. ROC areas reflecting these same results reached values above .80. Questions on matters that demanded the participants' attention and were easier to remember had better discriminative power. With nearly all scoring methods, there was a significant interaction between the salience of the relevant items and the guilt of the participants. Participants reacted more strongly to salient relevant items when they were guilty, while no different reactions were observed for the non-salient items between guilty and innocent participants. It is suggested that, although the Guilty Knowledge Test appears to be a valid measure of guilty knowledge even in crimes that are close to real crimes, the principles on which guilty knowledge test questions are constructed should be more clearly specified. 相似文献
8.
The anticonvulsant drug phenytoin, in less than cytotoxic concentrations, caused significant reductions in Ig secretion by unstimulated or EBV-stimulated normal MNC, as measured by PFC or secretion of Ig into the culture medium. Isotype-specific LBL varied in their sensitivity, the secretion of IgA (1 line) and IgG (3 lines) being reduced by phenytoin near therapeutic concentrations, whereas that of IgM (1 line) was resistant. Six-day exposure of MNC to phenytoin caused no selective depletion of or enrichment for B cells, monocytes or T cell subsets. The results suggest that the reduction in serum Ig levels reported in phenytoin-treated epileptic patients is, at least in part, due to a direct effect of the drug on the B lymphocyte. However, among EBV-activated normal MNC, those secreting IgA were no more sensitive to the drug than those secreting IgG or IgM, and other factors may, therefore, operate to cause the preferential reduction in serum IgA in phenytoin-treated patients. 相似文献
9.
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
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