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Background Perceived age is important to women and is a primary driver for topical product use and facial cosmetic surgery. Changes in facial features and biophysical skin parameters with chronological age and their associations with perceived age have not been described in Asian populations. Objective To investigate the relationship between biophysical properties of the skin, visual features of skin ageing and perceived facial age in Chinese women. Methods Facial photographs were collected of 250 Chinese women, aged 25–70 years in Shanghai, China. The perceived facial age was determined and related to the chronological age for each participant and to a range of visual assessments of skin appearance and objective biophysical measurements of the skin. The profile of changes in these parameters with age was investigated together with the differences in those parameters for women judged to look younger than their chronological age and those judged to look older than their chronological age. Results Large discrepancies in perceived age (up to 29 years) were found in women of the same chronological age. Each objective skin measure and visual assessment parameter had a stronger correlation with perceived age than with chronological age. The strongest relationships to perceived age were for wrinkles and hyperpigmentation. Skin colour, hydration and trans‐epidermal water loss (TEWL) had weaker associations with perceived age. Women judged to look older than their chronological age had significantly higher scores than those judged to look younger for coarse wrinkles and hyperpigmentation across all age groups. The appearance differences between these groups were evident in composite facial images of the same average chronological age. Conclusions We have identified the skin attributes which differ with perceived age in Chinese women. Perceived age is a better measure of the biological age of facial skin than is chronological age in this population.  相似文献   
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Rademaker KJ, Groenendaal F, Jansen GH, Eken P, de Vries LS. Unilateral haemorrhagic parenchymal lesions in the preterm infant: shape, site and prognosis. Acta Pædiatr 1994;83:602–8. Stockholm. ISSN 0803–5253 In a prospective cranial ultrasound study of 544 infants with a gestational age of 32 weeks or less, 20 (3.6%) infants were diagnosed as having a unilateral parenchymal lesion (PL). Based on the shape of the PL and the evolution on ultrasound, the infants were divided into three groups: group I consisted of 11 infants, in whom the PL was triangular/fan-shaped and separate from the ventricle. The PL evolved into small cystic lesions; group II comprised 3 infants who had a PL with a similar shape, but partially communicating with the ventricle; group III consisted of 6 infants who had a globular-shaped lesion in communication with the ventricle. In groups II and III, the PL evolved into one porcncephalic cyst. The PL was considered to be due to venous infarction in all cases with intraventricular haemorrhage preceding the PL in 7 cases. Sixteen infants survived. A postmortem was performed in 2 of the 4 infants who died, confirming the diagnosis of venous infarction. Neurologicdl sequelae were present in only 2 cases in the first group, while all 6 survivors of the other two groups developed mild to severe hemiplegia. Long-term follow-up was not always available and 4 of the 18 survivors were still less than 18 months when last seen. In 9 of the 11 infants in group I, the PL was localized in the frontoparietal region, while in 8 of the 9 infants in group II or III, the PL was beyond the trigone in the occipital region. The outcome of the unilateral PL is not always unfavourable. It was evident that not only the shape of the lesion and whether or not there was communication with the lateral ventricle, but also the site of the lesion (whether or not it extended into the occipital periventricular white matter) appeared to be important with regard to neurodevelopmental outcome.  相似文献   
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Newlin  N; Silver  TM; Stuck  KJ; Sandler  MA 《Radiology》1981,139(1):155-159
Ultrasonic features of 21 surgically confirmed pyogenic liver abscesses in 18 patients were analyzed. Typical lesions were round or ovoid with a discrete, irregular, echo-poor margin. The number and intensity of internal echoes and sound transmission were variable. Such lesions can be aspirated percutaneously for definitive preoperative diagnosis. Pyogenic liver abscesses appear to have more ragged walls and are less frequently elliptical or multilocular than abscesses elsewhere in the abdomen.  相似文献   
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Gonadotropin-induced loss (down-regulation) of testicular lactogen receptors was studied in 5–60-day-old rats. An i.m. injection of 600 IU/kg of hCG elicited in 5-day-old animals a 38–56% increase in testicular lactogen binding, measurable between 6 and 72 h after the hormone injection. In contrast, at the age of 60 days the same hCG dose decreased lactogen receptors by 75% at 24 h, which loss recovered in 2–3 days. When the amount of lactogen receptors was measured 24 h after the hCG injection (600 lU/kg) at different ages, the binding increased on average by 50% between ages 5 and 20 days, no effect on binding was seen at day 30, and a loss of binding by 50% was evident in animals of 40 days of age and older. The present results indicate that the plasma-membrane events elicited by gonadotropin binding to neonatal Leydig cells are clearly different from those occurring in the adult, and that down-regulation and functional coupling of LH and lactogen receptors are accompaniments of functional differentiation of the Leydig cell during pubertal maturation.  相似文献   
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