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991.
Troisi E Silvestrini M Matteis M Monaldo BC Vernieri F Caltagirone C 《Journal of neurology》1999,246(12):1172-1176
This study assessed the use of transcranial Doppler ultrasound in detecting selective changes in cerebral blood flow velocity
during emotional processes. The role of the respective hemispheres in emotional processing is controversial. Cerebral control
of emotional processing has previously been investigated by analysis of patients with unilateral brain damage, experiments
with selective stimulation of only one hemisphere, and more recently by imaging techniques measuring local cerebral blood
flow. We investigated mean flow velocity continuously and simultaneously in both the right and left middle cerebral arteries
(MCAs) in 16 healthy right-handed young subjects at rest and during the performance of three tasks: task 1: 15 slides with
nonemotional content; task 2: 15 slides with negative emotional content; task 3: 15 slides with nonemotional content with
different content from that in task 1. The three tasks produced significantly different effects on the right and left hemispheres.
During the two nonemotional tasks the increase in mean flow velocity over basal values was similar in the two MCAs (task 1:
left MCA = 3.27 ± 1.9%; right MCA = 3.63 ± 2.1%; task 3: left MCA = 2.42 ± 0.7%; right MCA = 2.56 ± 1.3%); the negative emotional
task was accompanied by a significantly higher increase in the right (11.31 ± 1.6%) than in the left MCA (4.72 ± 3.7%; analysis
of variance two-way interaction: side of recording x task, F = 43.6, P < 0.001). These results show the possibility of obtaining specific functional information from bilateral transcranial Doppler
ultrasound and suggest the involvement of the right hemisphere in emotional processing.
Received: 4 March 1999 Received in revised form: 29 June 1999 Accepted: 5 August 1999 相似文献
992.
993.
994.
Destito A Servello C Pisanti F Pierconti F Orlando Candidi M Lacquaniti S 《Scandinavian journal of urology and nephrology》1999,33(5):338-339
Testis leiomyoma is a very rare neoplasm. It is very difficult to perform an exact preoperative diagnosis; only histological examination can prove the presence of a leiomyoma. In our case radical orchidectomy was performed because of complete substitution of normal parenchyma, the extreme rarity at long-term follow-up of a reported benign intratesticular neoplasm, and the imperfect sensitivity of the extemporary histological examination. 相似文献
995.
996.
Screening for mutations in candidate genes for hypospadias 总被引:2,自引:0,他引:2
Nordenskjöld A Friedman E Tapper-Persson M Söderhäll C Leviav A Svensson J Anvret M 《Urological research》1999,27(1):49-55
Hypospadias, a condition with a frontally placed urethral orifice on the penis, is the most common malformation in males.
During fetal development several components are necessary for normal male genital development. Testosterone and dihydrotestosterone
act via the androgen receptor but a defective receptor function results in different degrees of genital malformations. Testosterone-5α-reductase
converts testosterone to dihydrotestosterone, which is crucial for normal differentiation, and a total lack of this enzyme
results, in syndromes with hypospadias. The Wilms' tumour 1 (WT1) gene is expressed in the fetal gonad and genital malformations
can occur due to WT1 gene mutations. These genes are therefore strong candidate genes for hypospadias. We have analysed 35
boys with hypopadias and one girl diagnosed as with complete androgen insensitivity syndrome, using exon by exon polymerace
chain reaction (PCR) amplification of the AR, WT1 and 5α-reductase genes and screened for point mutations and performed subsequent
DNA sequencing. No mutations in any of these genes were found in the 26 patients with isolated hypospadias. Two patients with
severe hypospadias with cryptorchidism were found to carry mutations in the androgen receptor gene. Also the girl with clinically
diagnosed complete androgen insensitivity was found to be homozygous for a splice mutation in the 5α-reductase gene. In summary,
mutations in the WT1, AR and 5α-reductase genes are not common causes of isolated hypospadias.
Received: 1 October 1997 / Accepted: 4 May 1998 相似文献
997.
The Ultrapulse CO2 laser (Coherent Inc., Palo Alto, CA, USA) was used in 239 patients, from March 1996 to July 1998, for full-face laser resurfacing.
In 106 (43%) of these patients rhytidectomy was performed in the same procedure. All patients submitted to laser resurfacing
were prepared for 1 to 2 months beforehand with retinoic acid and hydroquinone. The procedures were done under local anesthesia
controlled by an anesthesiologist. A clear film dressing impregnated with silicone gel (Silon TSR; Bio-Med Sciences, Bethlehem,
PA, USA) was used for 6 to 7 days and complete healing was observed in 7 to 10 days. Complications were exclusively dermatologic,
without relation to surgery. No necrosis of the cutaneous flap was observed. Skin biopsies of 10 consecutive patients undergoing
the combined procedures revealed no vascular impairment to the dermis. The patients were able to resume their activities 2
weeks after the procedure. 相似文献
998.
Salvatore Squarcione Maria G. Pompa Daniela D'Alessandro 《European journal of epidemiology》1999,15(7):685-687
In 1994, the Italian Ministry of Health implemented a National Surveillance System to obtain data on the incidence of bacterial meningitis and its causative agents, including Haemophilus influenzae type b (Hib). As a consequence, case reporting of Hib meningitis is increasing year by year; in 1996, there were 126 notifications, of which 73% were in children under 2 years of age. Although underreporting still exists, parallel prospective or retrospective epidemiological surveys conducted in some Italian Regions allowed for partial correction of the incidence of Hib meningitis (up to 18.5/100,000 population in 1994). 相似文献
999.
David R. Stager Jr MDa b Marshall M. Parks MDb c David R. Stager Sr MDa b Maria Pesheva MDb 《Journal of AAPOS》1999,3(6):328
Background: The treatment of Brown syndrome has been undergoing an evolution toward more effective procedures with fewer operative interventions. Dr Kenneth Wright has introduced a procedure of superior oblique muscle tenotomy with a silicone expander to reduce the incidence of overcorrection. Methods: There was a retrospective study of 20 eyes of 19 consecutive patients with moderate or severe Brown syndrome (Brown syndrome “plus”). Follow-up ranged from 12 to 72 months. The expander, which varies 6 to 10 mm in length, was placed in all patients in the tenotomized superior oblique muscle tendon 5 mm nasal to the nasal border of the superior rectus muscle using 7-0 or 8-0 Prolene suture without violating the inner layer of the intermuscular septum. The intermuscular septum was closed over the silicone expander. Results: One hundred percent of patients had resolution of the down shoot in adduction and some or full ability to elevate the eye in adduction. Twenty percent of patients required reoperation (12.5% using 5-8 mm expanders) for overcorrection. Restriction of downgaze was not seen postoperatively. Patients often show an undercorrection 1 to 6 months postoperatively and improve or occasionally overcorrect at 1 to 2 years postoperatively. One patient with a 10-mm expander extruded the implant. Discussion: Placement of a 5- to 8-mm silicone expander in the tenotomized superior oblique muscle tendon is an effective means of correcting Brown syndrome with a low rate of reoperation. Initial undercorrection should not discourage the surgeon because improvement may continue for up to 3 years. The goal of treatment should be to convert a moderate or severe Brown syndrome (Brown syndrome plus) to a mild Brown syndrome (“true” Brown syndrome). Conclusion: This technique reduces the need for either simultaneous or subsequent inferior oblique muscle weakening and represents an advance in the treatment of Brown syndrome. (J AAPOS 1999;3:328-32) 相似文献
1000.
Luciano Saso Giovanni Valentini Eleonora Mattei Claudio Panzironi Maria Luisa Casini Eleonora Grippa Bruno Silvestrini 《Archives of pharmacal research》1999,22(5):485-490
The mechanism of action of fish oil (FO), currently used in different chronic inflammatory conditions such as rheumatoid arthritis (RA), is not completely understood, although it is thought that it could alter the metabolism of endogenous autacoids. In addition, we hypothesized that the known capability of fatty acids (FA) of stabilizing serum albumin and perhaps other proteins, may be of pharmacological relevance considering that it is shared by other anti-rheumatic agents (e.g. nonsteroidal antiinflammatory drugs). Thus, we studied the effect of oral administration of FO and corn oil (CO), a vegetable oil with a different composition, on the stability of rat serum proteins, evaluated by a classical in vitro method based on heat-induced protein denaturation. FO, and, to a lower extent, CO inhibited heat-induced denaturation of rat serum (RS): based on the inhibitory activity (EC50) of the major fatty acids against heat-induced denaturation of RS in vitro, it was possible to speculate that in vivo effects of palmitic acid (C16:0) and eicosapentaenoic acid (EPA, C20:5, n-3) may be more relevant than that of linolenic acid (C18:2). To better investigate this phenomenon, we extracted albumin from the serum of animals treated or not with FO with a one-step affinity chromatography technique, obtaining high purity rat serum albumin preparations (RSA-CTRL and RSA-FO), as judged by SDS-PAGE with Coomassie blue staining. When these RSA preparations were heated at 70 degrees C for 30 min, it was noted that RSA-FO was much more stable than RSA-CTRL, presumably due to higher number of long chain fatty acids (FA) such as palmitic acid or EPA. In conclusion, we provided evidences that oral administration of FO in the rat stabilizes serum albumin, due to an increase in the number of protein bound long chain fatty acids (e.g. palmitic acid and EPA). We speculate that the stabilization of serum albumin and perhaps other proteins could prevent changes of antigenicity due to protein denaturation and glycosylation, which may trigger pathological autoimmune responses, suggesting that this action may be involved in the mode of action of FO in RA and other chronic inflammatory diseases. 相似文献