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31.
D Sloan S Browne D Meagher A Lane C Larkin P Casey N Walsh E O'Callaghan 《European psychiatry》1996,11(8):407-411
This study investigated the attitudes of medical students towards psychiatry, both as a subject on the medical curriculum and as a career choice. Three separate questionnaires previously validated on medical student populations were administered prior to and immediately following an 8-week clinical training programme. The results indicate that the perception of psychiatry was positive prior to clerkship and became even more so on completion of training. On completion of the clerkship, there was a rise in the proportion of students who indicated that they might choose a career in psychiatry. Attitudes toward psychiatry correlated positively with the psychiatry examination results. Those that intended to specialise in psychiatry achieved significantly higher examination scores in the psychiatry examination. 相似文献
32.
Summary With the wider availability of magnetic resonance imaging cavernous malformations are being recognised with increasing frequency in those patients presenting with intractable epilepsy. Surgical resection is the treatment of choice. However, because these lesions are usually small and may be located in eloquent areas stereotactic resection should be considered. Stereotactically-guided resection of pathologically verified cavernous angiograms was performed in 10 patients in this series presenting with epilepsy (8 males, 2 females, mean age 32 years). Eight patients presented with medically intractable epilepsy (5 complex partial seizures, 3 grand mal seizures). Of the remaining patients one experienced multiple episodes of haemorrhage and the other headaches (with a non-diagnostic scan) both in association with epilepsy. Pre-operative localisation of the motor strip was determined in one case by functional MRI. Following resection of these lesions all patients experienced improved seizure control with a mean follow-up period of 22 months. The mean postoperative hospital stay was 5.1 days with no surgical complications recorded. We conclude that stereotactically-guided resection offers significant advantages in the management of cavernous malformations.Surgical indications for operative resection would include medically refractory epilepsy, repeated haemorrhage and those cases where there is diagnostic uncertainty. 相似文献
33.
34.
Mutations in the retinal guanylate cyclase (RETGC-1) gene in dominant cone-rod dystrophy 总被引:3,自引:0,他引:3
Kelsell RE; Gregory-Evans K; Payne AM; Perrault I; Kaplan J; Yang RB; Garbers DL; Bird AC; Moore AT; Hunt DM 《Human molecular genetics》1998,7(7):1179-1184
The dominant cone-rod dystrophy gene CORD6 has previously been mapped to
within an 8 cM interval on chromosome 17p12-p13. The retinal- specific
guanylate cyclase gene (RETGC-1), which maps to within this genetic
interval and previously was implicated in Leber's congenital amaurosis, was
screened for mutations within this family and in a panel of small families
and individuals with various cone and cone- rod dystrophy phenotypes. A
missense mutation (E837D) was identified in affected members of the CORD6
family, as well as a second missense mutation (R838C) in three other
families with dominant cone-rod dystrophy. RETGC-1 is only the fourth gene
to be implicated in cone-rod dystrophy and this is the first report of
dominant mutations in this gene.
相似文献
35.
R Cabannes P Amegnizin A Sangare D Arne R Casey H Lehmann 《Journal of medical genetics》1980,17(3):183-186
A family is described in which the proband is homozygous and several relatives are heterozygous for Hb K Woolwich (beta 130 [H10] Lys leads to Gln). These people are clinically and haematologically normal. The relationship between the presence of Hb K Woolwich and beta +-thalassaemia is discussed. The distribution of Hb K Woolwich in West Africa is discussed and it is seen to be closely associated with the Akan group. 相似文献
36.
Physical characteristics of the ECAT EXACT3D positron tomograph 总被引:9,自引:0,他引:9
Spinks TJ Jones T Bloomfield PM Bailey DL Miller M Hogg D Jones WF Vaigneur K Reed J Young J Newport D Moyers C Casey ME Nutt R 《Physics in medicine and biology》2000,45(9):2601-2618
The 'EXACT3D' positron tomograph, which is now in routine clinical research use, was developed with the aim of achieving unprecedented sensitivity, high spatial and temporal resolution and simplicity of design using proven detector technology. It consists of six rings of standard detector blocks (CTI/Siemens EXACT HR+) with 4.39 mm x 4.05 mm x 30 mm elements, giving an axial field of view (FOV) of 23.4 cm. This extended FOV and the absence of interplane septa and retractable transmission rod sources has allowed greatly simplified gantry and detector cassette design. Operation in exclusive 3D mode requires an alternative to the conventional coincidence method for transmission scanning, and a single photon approach using a hydraulically driven 137Cs point source has been implemented. The tomograph has no other moving parts. A single time frame of data without any compression is very large (> 300 Mbyte) and two approaches are employed to overcome this difficulty: (a) adjacent sinograms can be summed automatically into different combinations and (b) listmode (event-by-event) acquisition has been instituted, which is both storage efficient (particularly for acquisition of sparse data sets) and maximizes temporal resolution. The high-speed I/O and computing hardware can maintain a sustained acquisition rate of about 4 million coincidence events per second. A disadvantage of the large axial FOV in 3D is the increased sensitivity to activity outside the coincidence FOV. However, this can be minimized by additional side shielding. The mean spatial resolution is 4.8 +/- 0.2 mm FWHM (transaxial, 1 cm off-axis) and 5.6 +/- 0.5 mm (axial, on-axis). Its absolute efficiency is 5.8% for a line source in air (just spanning the axial FOV) and 10% for a central point source (with thresholds of 350-650 keV). For a uniform 20 cm diameter cylinder, the efficiency is 69 kcps kBq(-1) ml(-1) (after subtraction of a scatter fraction of 42%). Sensitivity relative to the EXACT HR+ (with four rings of blocks) is 2.5 (3D) and 12 (2D) times respectively. The rate of random events in blood flow studies in the brain and body, using 15O-labelled water, can be controlled by limiting the administered dose and inserting additional side shielding. 相似文献
37.
38.
Anderson RA; Wallace AM; Kicman AT; Wu FC 《Human reproduction (Oxford, England)》1997,12(8):1657-1662
Administration of supraphysiological doses of testosterone to normal men
causes inhibition of spermatogenesis, but while most become azoospermic,
30-55% maintain a low rate of spermatogenesis. We have investigated whether
there are differences in endogenous androgen production, of testicular and
adrenal origin, which may be related to the degree of suppression of
spermatogenesis. Thirty-three healthy Caucasian men were given weekly i.m.
injections of 200 mg testosterone oenanthate (TE), 18 became azoospermic,
while 15 remained oligozoospermic. Urinary excretion of epitestosterone, a
specific testicular product, was reduced to <10% of pretreatment values,
with no differences between the groups. Similar results were obtained for
other markers of testicular steroidogenesis. Urinary and plasma adrenal
androgens were also reduced during TE treatment: a statistically
significant decrease in both (P < 0.001 and P < 0.05 respectively)
was seen in the azoospermic but not oligozoospermic responders. These
results suggest that testicular steroidogenesis is decreased to <10% by
the administration of supraphysiological doses of exogenous testosterone.
Differences in the degree of ongoing steroidogenesis in the testis do not
appear to account for incomplete suppression of spermatogenesis, thus
differences in androgen metabolism may underlie this heterogeneous
response. A small but significant reduction in secretion of adrenal
androgens was also detectable, the relevance of which is unclear.
相似文献
39.
Summary Five normal men performed seven sets of seven squats at a load equal to 80% of their seven repetition maximum. Plasma growth
hormone (GH) and lactate levels increased during and after the completion of the exercise. A significant (r=0.93, P<0.001) linear correlation was found between GH changes and the corresponding oxygen Demand/Availability (D/A) ratio expressed
by
(where f=[lactate at time x]/[lactate at time 0]). A retrospective examination of previously published data from our laboratory and others also demonstrated
the existence of a significant correlation between changes in plasma GH levels and the D/A ratios over a wide variety of exercise;
aerobic and anaerobic, continuous and intermittent, weight lifting and cycling, in both fit and unfit subjects under normoxic
and hypoxic conditions. It is suggested that the balance between oxygen demand and availability may be an important regulator
of GH secretion during exercise.
DCIEM No. 87-P-27 相似文献
40.
Berry V; Ionides AC; Moore AT; Plant C; Bhattacharya SS; Shiels A 《Human molecular genetics》1996,5(3):415-419
Inherited cataract is a clinically and genetically heterogeneous disease.
Here we report the identification of a new locus for an autosomal dominant
anterior polar cataract on the short arm of chromosome 17. To map this new
locus we performed genetic linkage analysis with microsatellite markers in
a four-generation pedigree. After exclusion of seven candidate loci for
cataract, we obtained significant positive LOD scores for markers D17S849
(Z = 4.01 / theta = 0.05) and D17S796 (Z = 4.17 / theta = 0.05). Multipoint
analysis gave a maximum LOD score of 5.2 (theta max = 0.06) between these
two markers. From haplotype analysis, the cataract locus lies in the 13 cM
interval between markers D17S849 and D17S796. This study provides the first
genetic mapping of an autosomal dominant anterior polar cataract.
相似文献