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71.
After the introduction of the colposcope for the examination of children suspected of being sexually abused in Leeds, a study was undertaken to describe the findings in detail. A total of 109 consecutive prepubertal girls, mean age 70.4 months were assessed including colposcopic genital and anal examination, and peer group review of reports and photographs. Fifty nine children had signs consistent with blunt force penetrating trauma (hymenal transection/major notch, scar, or hymenal attenuation). Transections were encountered most commonly at 6 o'clock (directly posterior). In 46 the hymenal orifice was gaping with thigh abduction only and in 47 the hymenal orifice transverse diameter was greater than 4 mm on labial separation. Overall, physical findings were commonly present and in only two cases were no signs recorded. Non-specific and frequent findings included patterns of labial and introital reddening. Supportive hymenal signs including swelling, rounding of edge, thickening, distortion, and loss of symmetry were common. Labial fusion was present in 20. Urethral dilatation with labial separation was noted in 14. Physical findings including normality are consistent with abuse and even minor anogenital signs as well as negative findings should be documented. Colposcopy and photography are valuable tools in peer review, teaching, and case management. 相似文献
72.
Ambrosi A Fersini A Tartaglia N De Fazio M Cignarelli M Neri V 《Il Giornale di chirurgia》2002,23(4):129-133
The thyroglossal duct cyst is the most common anomaly in thyroid development. To date, approximately 250 cases have been reported, the majority being papillary thyroid carcinomas. In most cases the diagnosis is established only after excision of a clinically benign thyroglossal duct cyst. Controversies exist in relation to a rational and effective therapeutic approach. A further case of thyroglossal duct papillary carcinoma affecting a 52 years-old man is presented to highlight the clinicopathological features of this condition. FNAC resulted false negative. Surgery consisted in a Sistrunk procedure, followed by total thyroidectomy and central lymphectomy after definitive histological diagnosis. In view of the prolonged course of papillary carcinoma, long-term follow-up is mandatory. 相似文献
73.
Evidence of an influence of asymmetrical occlusal interferences on the activity of the sternocleidomastoid muscle 总被引:2,自引:0,他引:2
To investigate the hypothesis of a functional coupling between occlusion and neck muscles, the immediate effect of asymmetrical occlusal interferences on the pattern of contraction of the sternocleidomastoid muscles (SCM) during maximum voluntary clench (MVC) was analysed in 30 healthy subjects. All subjects had a complete and sound permanent dentition, without temporomandibular joint (TMJ) and craniocervical disorders. A 5-s surface electromyogram (EMG) examination of the SCM was performed during (1) MVC in intercuspal position and (2) MVC with a single 200-microm occlusal interference alternatively positioned on teeth 16, 13, 23, 26. All subjects had a symmetrical EMG activity during MVC in intercuspal position. For each subject, SCM potentials were standardized as percentage of the mean potentials recorded during the MVC on natural dentition and the EMG waves of left- and right-side muscles were compared by computing the relevant percentage overlapping coefficient (POC). For each subject, the best and the worst POCs computed during the four MVC tests with occlusal interferences were found and the percentage difference between them was calculated. In the four MVC tests with occlusal interferences, SCM symmetry was very different from that recorded during MVC on natural dentition. The difference between the best and worst POCs computed within each subject was very variable, ranging from 1.52 to 41.57%. In conclusion, when young healthy subjects with a normal occlusion clench on an asymmetrical occlusal interference, they have an altered left-right side pattern of contraction of their SCM. In almost all subjects, a previously symmetrical pattern became asymmetrical. 相似文献
74.
Magnetization transfer can predict clinical evolution in patients with multiple sclerosis 总被引:3,自引:0,他引:3
Santos AC Narayanan S de Stefano N Tartaglia MC Francis SJ Arnaoutelis R Caramanos Z Antel JP Pike GB Arnold DL 《Journal of neurology》2002,249(6):662-668
The clinical course of multiple sclerosis (MS) is highly variable ranging from benign to aggressive, and is difficult to
predict. Since magnetization transfer (MT) imaging can detect focal abnormalities in normal-appearing white matter (NAWM)
before the appearance of lesions on conventional MRI, we hypothesized that changes in MT might be able to predict the clinical
evolution of MS. We assessed MR data from MS patients who were subsequently followed clinically for 5 years. We computed the
mean MT ratio (MTr) in gray matter, in lesions identified on T2-weighted MRI, and in NAWM, as well as in a thick central brain
slice for each patient. Patients were divided into stable and worsening groups according to their change in Expanded Disability
Status Scale (EDSS) scores over 5 years. We calculated the sensitivity, specificity, predictive value, and odds ratio of the
baseline MTr measures in order to assess their prognostic utility. We found significant differences in baseline MTr values
in NAWM (p = 0.005) and brain slice (p = 0.03) between clinically stable and worsening MS patients. When these MTr values
were compared with changes in EDSS over 5 years, a strong correlation was found between the EDSS changes and MTr values in
both NAWM (SRCC = −0.76, p < 0.001) and in the brain slice (SRCC = 0.59, p = 0.01). Baseline NAWM MTr correctly predicted clinical evolution in 15/18 patients (1 false positive and 2 false negatives),
yielding a positive predictive value of 77.78 %, a negative predictive value of 88.89 %, and an odds ratio of 28. The relationship
between 5-year changes in EDSS and MTr values in T2 weighted MRI lesions was weaker (SRCC = −0.43, p = 0.07). Our data support the notion that the quantification of MTr in the NAWM can predict the clinical evolution of MS.
Lower MTr values predict poorer long-term clinical outcome. Abnormalities of MTr values in the NAWM are more relevant to the
development of future patient disability than those in the T2-weighted MRI lesions.
Received: 3 May 2001, Received in revised form: 11 October 2001, Accepted: 22 October 2001 相似文献
75.
Functional characteristics of electrically stimulated quadriceps muscles of patients with multiple sclerosis (MS) were determined to investigate whether adaptations in muscle properties contribute to the higher fatigability of these patients. The estimated maximal isometric force generating capacity of MS patients was only 11.2% (P < 0.05) lower than control subjects. However, the patients were only able to voluntarily exert 75 +/- 22% (n = 12) of their maximal capacity, against 94 +/- 6% (n = 7) for the control subjects. There were no differences in muscle speed, suggesting that muscle fiber distribution was not different in the MS patients due to reduced muscle usage. During a series of repeated contractions, greater decrements occurred in isometric force and in maximal rate of force rise in the MS patients (by 31.3 +/- 10.3% and 50.1 +/- 10.0%, respectively; n = 13) than control subjects (23.8 +/- 6.6% and 39.0 +/- 8.1%, n = 15), suggesting a lower oxidative capacity. The results indicate that increasing the mass of their muscles by training may help to reduce the excessive muscle fatigue of MS patients. 相似文献
76.
PURPOSE: In pre-clinical gene therapy studies of bladder cancer there is tremendous variation in the ability of viral vectors to deliver genetic material to bladder epithelium. Possible explanations for this variability may involve the physical parameters of delivering vectors in these experimental models. We examined the effects of intravesical volume and pressure during instillation as well as chemical modification of the bladder epithelium on subsequent gene expression in the bladder in mice. MATERIALS AND METHODS: Female C57B1/6 mice underwent intravesical instillation of the replication restricted canarypox virus (ALVAC) recombinant for the reporter genes luciferase or beta-galactosidase. Similar viral titers were instilled at different volumes and a pressure transducer measured intravesical pressure when the vector was instilled. Also, various agents, including 0.6 N hydrochloric acid, 0.4% oxychlorosene, poly-L-lysine and 0.25 M. ammonium chloride, were used to modify the bladder surface before vector instillation and then assayed for transgene expression. RESULTS: As expected, maximum intravesical pressure measured during instillation was significantly greater in mice instilled with a higher volume (33.1 versus 9.8 mm. Hg). Significantly more gene expression was detected in bladders instilled with a higher volume of viral vectors (p <0.05). Likewise, higher instillation pressures resulted in higher transgene expression in distant organs. Modification of the bladder epithelium with agents such as oxychlorosene and poly-L-lysine resulted in elevated gene expression with only minimal increases in systemic activity. CONCLUSIONS: Significant differences in gene expression are achieved by varying physical parameters during intravesical instillation. Increased gene expression associated with larger volume instillation may be responsible for some reported variability of gene transfer to the bladder. Alternate manipulations, such as modifying the bladder surface, may be done to enhance gene transfer to the urothelium without increasing systemic distribution. 相似文献
77.
78.
Epidemiological evidence indicates that aflatoxin B1 (AFB1) intake is
associated with an increased risk of hepatocellular carcinoma (HCC). The
hepatocarcinogenesis is initiated by covalent binding of AFB1 to cellular
DNA. To determine whether nutritional factors and hormonal status may
influence the binding of AFB1 to hepatic DNA, a cross- sectional study was
performed on a total of 42 male asymptomatic hepatitis B surface antigen
(HBsAg) carriers and 43 male non-carriers in a cohort study on the
multistage development of HCC in Taiwan. The major AFB1-DNA adduct in vivo,
AFB1-N7-guanine, was measured by high- performance liquid chromatography in
urine. Urinary AFB1-N7-guanine was detectable in 40% of the subjects. HBsAg
carriers had a higher detection rate of urinary AFB1-DNA adducts than
non-carriers and the difference was statistically significant after
multivariate adjustment. After taking into account the total AFB1 urinary
metabolite level, chronic HBsAg carrier status, and other potential
confounders, plasma levels of cholesterol, alpha-tocopherol, and alpha- and
beta-carotene were positively associated with the detection rate of the
AFB1-DNA adducts in a dose-dependent manner, whereas plasma lycopene level
was inversely related to the presence of the adducts in urine. The
association of urinary AFB1-DNA adducts with the plasma levels of
cholesterol, alpha-tocopherol, lycopene, and alpha- and beta-carotene was
observed at both low and high exposure levels of AFB1. There was a
synergistic interaction of plasma alpha-tocopherol with alpha- and beta-
carotene on the adduct levels. No association with the adducts was found
for plasma levels of retinol and testosterone. This study demonstrated
different associations of antioxidant vitamins with AFB1- DNA adduct
formation. The data consistent with our previous finding in cultured
woodchuck hepatocytes that alpha-tocopherol and beta-carotene enhanced
AFB1-DNA adduct formation suggest that prospective investigation of the
relationship between plasma micronutrients and risk of AFB1-related HCC is
warranted.
相似文献
79.
The dose of glucocorticoid was evaluated in the treatment of 19 patients with salt-losing congenital adrenal hyperplasia due to complete or nearly complete 21-hydroxylase deficiency. In most cases, follow-up was from infancy to puberty. The dose of steroid was expressed as oral cortisol (mg/m2 body surface area 124 hours); the equivalent doses of the various glucocorticoid preparations was as follows: 100 mg oral cortisol = 120 mg oral cortisone acetate = 25 mg oral prednisone = 50 mg intramuscular cortisol = 60 mg intramuscular cortisone acetate. The dose of glucocorticoid producing good laboratory and clinical control varied significantly with age. The dose fell from 26 mg/m2 /24 hours in early infancy to 19 mg/m2 /24 hours between 6 and 8 years of age, and then rose to 23–24 mglm2 /hour in adolescence. In addition to these age-related changes, there were large individual variations at each age. Indeed, the values from 4 of the 19 patients were not included in the calculation of the mean because they were more than 3 SD either above or below the mean. For the rest of the patients, the coefficient of variation ranged from 14.5% to 37.2%. It is concluded that glucocorticoid therapy must be adjusted carefully to the age and needs of each patient. 相似文献
80.
OBJECTIVE--To determine the prevalence of behaviour disorders in low birthweight infants. DESIGN--Children of birth weight < or = 2000 g born to mothers resident in Merseyside in 1980-1 assessed using the Rutter parent and teacher behaviour questionnaires and the Conner modification of the Rutter teacher questionnaire. Children attending normal schools were assessed with controls matched for age, sex, and class in school. Children attending special schools were assessed unmatched. SUBJECTS--233 matched case-control pairs attending normal primary schools and 46 unmatched children attending special schools. SETTING--Primary and special schools. MAIN OUTCOME MEASURES--Emotional, conduct, and undifferentiated behaviour disorders and hyperactivity. RESULTS--On the parental questionnaire screen, 36% of the cases and 22% of the controls had a behaviour disorder and on the teacher questionnaire the proportions were 27% and 12% respectively. Hyperactivity was significantly more common among male cases than their controls (21% v 5.0%) but differed little among female cases and controls (9% v 7%). CONCLUSIONS--Improving neonatal survival of low birthweight infants is accompanied by a higher prevalence of behaviour disorders. The long term implications for psychiatric morbidity and other adult disease must be monitored. 相似文献