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101.
Jean-Christophe Zech Laurette Morlé Pascale Vincent Nicole Alloisio Muriel Bozon Colette Gonnet Solange Milazzo Jean-Daniel Grange Christiane Trepsat Jacqueline Godet Henri Plauchu 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1999,237(5):387-393
· Background: It has been previously described that Wagner disease is linked to chromosome 5q13-q14. This study was carried
out to describe the ophthalmological aspects and report the results of genetic linkage analysis in a large pedigree affected
by Wagner disease. · Methods: Fourty members of one same family agreed to be examined. · Results: Twenty patients presented
vitreoretinal degeneration in both eyes without any extra-ocular abnormalities. In young patients, visual acuity was usually
normal after correction of frequent mild myopia. Presenile cataracts progressed by the third decade and required removal for
visual rehabilitation. The primary disorder involved an abnormal vitreous. A few avascular vitreous bands were usually the
only optical feature in the mostly empty vitreous cavity. A circumferential vitreous condensation formed in contact with the
retina on many spots. Less common retinal findings included retinal detachment, abnormal retinal pigmentation, progressive
atrophy of the RPE simulating choroideremia and lattice degeneration. Genetic analysis revealed a highly significant linkage
(lod score >5.0) between the disease and 10 markers of the chromosome 5q13-q14 region. Two recombination events allowed us
to refine the linked interval to 20 cM between the D5S650 and D5S618 markers. · Conclusion: Ophthalmological aspects of Wagner’s
disease appear to progress with age. Regular ophthalmological examination is important for detecting retinal abnormalities.
The gene involved in Wagner’s disease lies in a 20 cM interval on chromosome 5q13-q14.
Received: 30 June 1998 Revised version received: 5 October 1998 Accepted: 6 October 1998 相似文献
102.
Dr. Rolando Grave de Peralta Menendez Sara L. Gonzalez Andino Bernd Lütkenhöner 《Brain topography》1996,9(2):117-124
Summary This paper introduces the concept of the resolution matrix as the basis for an objective theoretical comparison of distributed linear inverse solutions to the neuroelectromagnetic inverse problem. In particular, we describe how figures of merit derived from the resolution matrices can be represented graphically to evaluate merits and shortcomings of the different solutions. The use of the figures of merit is illustrated with two solutions that consider minimal a priori information about the generators: Classical Minimum Norm and Backus Gilbert. We recommend to start any analysis with the individual exploration of the resolution kernel for each grid point or at least for those points where the activity is likely to occur. This analysis might help in selecting the optimal inverse for the sources that are supposed to be active in the process under study.This work was supported by a grant from the Deutsche Forschungsgemeinschaft (Klinische Forschergruppe Biomagnetismus and Biosignalanalyse). Partial support was received from Swiss National Foundation grant 4038-044081/1. 相似文献
103.
Barrett JS Hochadel TJ Morales RJ Rohatagi S DeWitt KE Watson SK DiSanto AR 《American journal of therapeutics》1996,3(10):688-698
This open-label, two-phase cross-over study compared the safety and pharmacokinetics of transdermally administered selegiline and orally administered selegiline hydrochloride in elderly men and women (n = 6/gender). Single oral doses of 10 mg selegiline hydrochloride and single 1/2 and 1 selegiline transdermal system (STS) (delivering similar3.4 and 6.3 mg over 24 h) administered topically were safe and well tolerated in all subjects. Plasma concentrations of selegiline (SEL) and its N-desmethylselegiline (DMS), L-amphetamine (AMP), and L-methamphetamine (MET) metabolites were measured using an HPLC/MS/MS method with lower quantitation limits of 10, 50, 200, and 200 pg/mL, respectively. No significant gender-related differences were observed following single 10-mg oral doses of selegiline hydrochloride or single 24-h applications of 1/2 and 1 STS to elderly males and females. The low level of dermal irritation as assessed by erythema and edema rating scales suggests that the STS was similar to Band-Aid (Johnson & Johnson, Skillman, NJ) controls. The transdermal administration of SEL bypasses the first-pass metabolism, that is significant after oral administration (first-pass extraction >90%). Peak plasma levels of 1.19, 23.22, 4.78, and 14.08 ng/mL were observed for SEL, DMS, AMP, and MET after a single 10-mg oral dose to the elderly. By contrast, peak plasma levels of 2.10, 0.85, 1.06, and 2.71 ng/mL were observed for SEL, DMS, AMP, and MET after a single 24-h application of 1 STS. Comparison of dose-corrected areas under the curve (AUCs) (made under the assumption of linear pharmacokinetics) indicate the SEL exposure after transdermal application was more than 50-fold greater than that obtained orally. This increase in systemic SEL exposure at the expense of metabolite formation that is reduced to <70% of that obtained orally for N-DMS, L-AMP, and L-MET is hypothesized to be of therapeutic value in patients with a variety of neurodegenerative and psychiatric disorders. 相似文献
104.
Christopher L. Amling Sara M. O''Hara John S. Wiener Cameron S. Schaeffer Lowell R. King 《The Journal of urology》1996,156(6):2020-2024
Purpose
We evaluated the use of renal ultrasound for monitoring pyelocaliectasis after pyeloplasty in children.Materials and Methods
Changes in pyelocaliceal dilatation following pyeloplasty were assessed by serial ultrasound. Of 104 children 0 to 12 years old who underwent pyeloplasty between 1982 and 1992, 44 (47 renal units) were monitored with serial ultrasound for at least 2 years (range 2 to 9, mean 3.8). Patient ages at pyeloplasty were 0 to 3 months (17), 4 to 12 months (8), 1 to 6 years (13) and 7 to 12 years (6). Preoperative and postoperative ultrasound was reviewed by a single pediatric radiologist blinded to the date of surgery. The degree of pyelocaliectasis was graded as 0 to 4 according to the classification of the Society for Fetal Urology.Results
Preoperative ultrasound revealed grade 4 pyelocaliectasis in 26 kidneys (55 percent) and grade 3 disease in 21 (45 percent). Grade was the same or worse 1 month after pyeloplasty in the majority of kidneys (92 percent) studied at this interval. Of the 47 renal units assessed 43 (91 percent) showed improvement in pyelocaliectasis during postoperative followup. Only 38 percent of the kidneys improved during the first 6 months of followup, while 81 percent were improved 2 years postoperatively. Improvement to grade 0 or 1 dilatation occurred in only 9 kidneys (19 percent). The rate of resolution of pyelocaliectasis was not related to preoperative grade or patient age at pyeloplasty.Conclusions
Improvement on renal ultrasound after pyeloplasty appears to be gradual. Less than half of the patients had improvement in the initial 6 months after pyeloplasty and pyelocaliectasis rarely resolved completely. While renal ultrasound can provide an accurate and cost-effective means of monitoring children on a long-term basis after pyeloplasty, sonographic evaluation in the early postoperative period commonly shows increased or unchanged pyelocaliectasis. 相似文献105.
Tetsumi Sato Kazuyoshi Hirota Akitomo Matsuki Elemer K. Zsigmond Sara F. Rabito 《Journal canadien d'anesthésie》1996,43(2):172-178
Purpose
Droperidol (D) is effective in the treatment of patients with status asthmaticus. It has been reported that D inhibits the bronchoconstriction induced by serotonin (5-HT) but not that by histamine (H) or acetylcholine. However, haloperidol, another butyrophenone, is known to interact with and inhibit calmodulin, an intracellular Ca++-binding protein which is important in the contraction of smooth muscles. The present study was designed to investigate the effects of D on tracheal contractions induced by 5-HT, H or carbachol (C) and to determine the contribution of α-adrenoceptors to the relaxant effect of D in vitro.Methods
Tracheas of female guinea pigs were cut spirally into strips and mounted in water-jacketed organ baths in Tyrode’s solution, aerated with a mixture of 95% O2 and 5% CO2 at 37°C. The changes in isometric tension induced by each spasmogen in the strips were measured with a transducer and a polygraph.Results
We found that D inhibited the tracheal contractions induced by 5-HT, H or C in a concentration-dependent manner. At 1.25 × 10?6 M D blocked the effect of 10?4 M 5-HT by 44.1 ± 4.3% and at 2.5 × 10?6 M by 63.8 ± 3.8%. Similarly, at 5.0 × 10?6 M concentration, D blocked the effect of 10?5 M H by 27.7 ± 5.3% and at 10?5 M by 56.2 ± 2.6%. Furthermore, 5 ×10?6 M of D reduced the contractions produced by 10?7 M C by 37.1 ± 3.0% and 70?5 M of D by 76.1 ± 3.2%. The inhibiting effect of D was strongest on contractions induced by 5-HT. Prazosin (70?6 M) affected neither 5-HT-induced contractions nor the inhibition by D.Conclusion
Our data indicate that D partially blocks the contractile responses not only to 5-HT, an effect which would be mediated through a blockade of the 5-HT receptors, but also to H or C, probably through inhibition of calmodulin. Our data support previous reports indicating that droperidol may be an important therapeutic agent in the treatment of patients with hyperreactive airways. 相似文献106.
Pietra N Sarli L Maccarini PU Sabadini G Costi R Gobbi S 《World journal of surgery》2000,24(3):345-352
Consensus has never been reached regarding the need or the imaging technique for evaluating the common bile duct (CBD) in
patients considered for cholecystectomy. With the advent of laparoscopic cholecystectomy there has been a resurgence of interest
in the role of preoperative intravenous cholangiography (IVC) as an alternative for evaluating the CBD. The purpose of this
audit was to assess whether a diagnostic workup based on IVC, which permits selective use of intraoperative cholangiography
(IOC) and endoscopic treatment of CBD stones before surgery, could be useful in patients undergoing laparoscopic cholecystectomy
(LC). In patients without jaundice, gallstone pancreatitis, a prior diagnosis of CBD stones, a prior history of contrast allergy,
or a risk of contrast-associated acute renal failure, IVC was performed routinely. Patients suspected to have CBD stones based
on IVC results or with inconclusive IVC and patients with a strong clinical suspicion of CBD stones were referred for endoscopic
retrograde cholangiography (ERC). IOC was carried out in patients who had a history of contrast allergy or risk of contrast-associated
acute renal failure and whenever the surgeon was in doubt as to the biliary anatomy or CBD clearance. IVC was carried out
in 1155 patients, ERC in 225, and IOC in 54. IVC was conclusive in 1132 patients, with a diagnostic accuracy of 99%. Our workup
permitted the sequential endoscopic-laparoscopic treatment of cholecystocholedocholithiasis in 162 cases. During the follow-up
period residual CBD stones were detected in four patients. Our diagnostic workup showed that routine IVC exposes the population
to a large radiation burden, and the cost is high for the small number of patients who benefit. Moreover, it does not seem
helpful in reducing the incidence of CBD injuries during LC. 相似文献
107.
p53 mutations in human aggressive and nonaggressive basal and squamous cell carcinomas. 总被引:6,自引:0,他引:6
Svetlana Bolshakov Christopher M Walker Sara S Strom Mano S Selvan Gary L Clayman Adel El-Naggar Scott M Lippman Margaret L Kripke Honnavara N Ananthaswamy 《Clinical cancer research》2003,9(1):228-234
PURPOSE: The purpose is to investigate whether aggressive basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) differ from nonaggressive BCC and SCC with respect to the p53 mutation spectrum and whether specific mutations can serve as prognostic indicators of tumor aggressiveness. EXPERIMENTAL DESIGN: We analyzed 342 tissues from patients with aggressive and nonaggressive BCCs and SCCs for p53 mutations by single-strand conformation polymorphism and nucleotide sequencing. RESULTS: p53 mutations were detected in 33 of 50 aggressive BCCs (66%), 37 of 98 nonaggressive BCCs (38%), 28 of 80 aggressive SCCs (35%), 28 of 56 nonaggressive SCCs (50%), and 3 of 29 samples of sun-exposed skin (10%). About 71% of the p53 mutations detected in aggressive and nonaggressive BCCs and SCCs were UV signature mutations. The frequency of CC to TT mutations in aggressive (36%) and nonaggressive SCCs (39%) was 2-fold higher than in aggressive (18%) and nonaggressive (14%) BCCs. In contrast, aggressive BCCs had a higher frequency (24%) of transversions than nonaggressive BCCs (8%) and aggressive (14%) and nonaggressive (11%) SCCs did. CONCLUSIONS: Our results indicate that UV radiation is responsible for the induction of p53 mutations and perhaps for the initiation of both aggressive and nonaggressive BCCs and SCCs. Although some differences in p53 mutation frequency, types of mutation, and hot spots were seen between aggressive and nonaggressive BCCs and SCCs, these factors do not constitute as clear-cut diagnostic or prognostic indicators of tumor aggressiveness. Tumor aggressiveness may be attributable to other genetic changes or events that occur during tumor progression. 相似文献
108.
We report three patients who developed severe supraglottic airway obstruction due to Epstein-Barr virus lymphoproliferative
disease following allogeneic bone marrow transplantation. In addition to enlarged pharyngeal lymphoid tissue seen in all three
patients, two had supraglottic airway narrowing and two developed pulmonary lymphoproliferative disease. They were treated
with unmanipulated T cells or EBV-specific cytotoxic T lymphocytes. Life-threatening upper airway obstruction is a radiologically
detectable complication of allogeneic bone marrow transplantation in children.
Received: 12 August 1997 Accepted: 11 December 1997 相似文献
109.
110.
Is there an incremental rise in the risk of obstetric intervention with increasing maternal age? 总被引:3,自引:0,他引:3
Adam N. Rosenthal Senior House Officer Sara Paterson-Brown Consultant Obstetrician Gynaecologist 《BJOG : an international journal of obstetrics and gynaecology》1998,105(10):1064-1069
Objective To determine whether increasing maternal age increases the risk of operative delivery and to investigate whether such a trend is due to fetal or maternal factors.
Design Analysis of prospectively collected data on a maternity unit database.
Setting A postgraduate teaching hospital.
Population 6410 nulliparous women with singleton cephalic pregnancies delivering at term (37–42) weeks of gestation) between 1 January 92 and 31 December 95.
Main outcome measures Mode of delivery, rates of prelabour caesarean section, induction of labour and epidural usage.
Results There was a positive, highly significant association between increasing maternal age and obstetric intervention. Prelabour ( P < 0.001 ) and emergency ( P < 0.001 ) caesarean section, instrumental vaginal delivery (spontaneous labour P < 0.001 ; induced labour P = 0.001 ), induction of labour ( P < 0.001 ) and epidural usage in spontaneous labour ( P = 0.005 ) all increased with increasing age. In the second stage of labour fetal distress and failure to advance, requiring instrumental delivery, were both more likely with increasing maternal age (in both P < 0.001 ). Epidural usage in induced labour and the incidence of small for gestational age newborns did not increase with increasing maternal age (P = 0.68 and P = 0.50 , respectively).
Conclusions This study demonstrates that increasing maternal age is associated with an incremental increase in obstetric intervention. Previous studies have demonstrated a significant effect in women older than 35 years of age, but these data show changes on a continuum from teenage years. This finding may reflect a progressive, age-related deterioration in myometrial function. 相似文献
Design Analysis of prospectively collected data on a maternity unit database.
Setting A postgraduate teaching hospital.
Population 6410 nulliparous women with singleton cephalic pregnancies delivering at term (37–42) weeks of gestation) between 1 January 92 and 31 December 95.
Main outcome measures Mode of delivery, rates of prelabour caesarean section, induction of labour and epidural usage.
Results There was a positive, highly significant association between increasing maternal age and obstetric intervention. Prelabour ( P < 0.001 ) and emergency ( P < 0.001 ) caesarean section, instrumental vaginal delivery (spontaneous labour P < 0.001 ; induced labour P = 0.001 ), induction of labour ( P < 0.001 ) and epidural usage in spontaneous labour ( P = 0.005 ) all increased with increasing age. In the second stage of labour fetal distress and failure to advance, requiring instrumental delivery, were both more likely with increasing maternal age (in both P < 0.001 ). Epidural usage in induced labour and the incidence of small for gestational age newborns did not increase with increasing maternal age (P = 0.68 and P = 0.50 , respectively).
Conclusions This study demonstrates that increasing maternal age is associated with an incremental increase in obstetric intervention. Previous studies have demonstrated a significant effect in women older than 35 years of age, but these data show changes on a continuum from teenage years. This finding may reflect a progressive, age-related deterioration in myometrial function. 相似文献