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101.
AM Elliman EM Bryan AD Elliman DR Harvey 《Acta paediatrica (Oslo, Norway : 1992)》1992,81(10):836-839
Correction for gestational age continues to make a difference to the height SD score (SDS) to the age of seven years in very preterm babies. The height SDS for children born at 28 weeks' gestation increased by 0.25 SDS when postconceptual age was used instead of real age. Extrapolating from these results, the effect of correction would be an increase of approximately 0.32 SDS for a seven-year-old of 24 weeks' gestation. Unsatisfactory growth may be masked by a steady or increasing real age SDS in a few children. The risks of stopping using postconceptual age at two or three years include both false confidence in genuine cases of growth retardation and misinterpretation of a decrease in height SDS as evidence of growth retardation. As the number of very preterm babies who survive increases so does the importance of these observations. 相似文献
102.
Gadopentetate dimeglumine (gadolinium diethylenetriaminepentaacetic acid [DTPA]) was administered prospectively to 500 consecutive children and adults referred for routine cranial magnetic resonance (MR) imaging over a 4-month period. Pre- and postcontrast images were blindly and independently interpreted by two experienced neuroradiologists. Specific criteria were provided to the readers to define objectively when contrast material enhancement (or lack thereof) would be considered "radiologically helpful." Contrast-enhancing lesions were observed in 99 cases (20%). In only 15 cases (3%) did Gd-DTPA permit detection of lesions not also apparent on the precontrast studies. Contrast enhancement was considered radiologically helpful in 74 of the 99 cases. Lack of enhancement was considered helpful in 112 of the 500 cases (22%). Factors that may indicate increased usefulness of Gd-DTPA include increased patient age, definite lesion seen at computed tomography or precontrast MR imaging, prior craniotomy for tumor, and clinically documented systemic or central nervous system disease. Gd-DTPA should probably be used routinely for cranial MR imaging in most patients, except, perhaps, children and young adults with normal precontrast images. 相似文献
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Differential interleukin-1 elaboration by density-defined human monocyte subpopulations 总被引:1,自引:0,他引:1
Interleukin-1 (IL-1) is an important immunoregulatory peptide produced by monocytes and macrophages. Because mononuclear phagocytes are morphologically and functionally heterogeneous, we examined whether they differ in their ability to elaborate IL-1. We used discontinuous Percoll gradients to obtain five density-defined human blood monocyte subpopulations. Unfractionated monocytes and their subsets were compared for their ability to stimulate thymocyte proliferation. Supernatants obtained from the denser monocytes consistently contained more IL-1 activity than did supernatants from the less dense cells. This difference in IL-1 activity was the result of differences in IL-1 elaboration, not the selective production of an inhibitor of IL-1- induced thymocyte proliferation. These data demonstrate that density- defined human monocyte subpopulations differ in their capacity to elaborate IL-1. 相似文献
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106.
N Pluchino AD Genazzani F Bernardi E Casarosa M Pieri M Palumbo 《Gynecological endocrinology》2013,29(3):144-149
The aim of the present study was to evaluate, in healthy postmenopausal women, the impact of tibolone (2.5?mg), transdermal estradiol (50?μg) (TE) and different oral estrogen–progestin regimens, conjugated equine estrogens (0.625?mg) plus medroxyprogesterone acetate (5?mg) (CEE?+?MPA) and estradiol (2?mg) plus norethisterone acetate (1?mg) (E2?+?NETA) on circulating estradiol, progesterone, allopregnanolone, cortisol and dehydroepiandrosterone (DHEA) levels. Blood samples were collected before and after 1, 3, 6 and 9 months of treatment in 85 postmenopausal women. Estradiol levels increased (p?<?0.001) in the TE, CEE?+?MPA and E2?+?NETA groups after 1 month of therapy, but did not change in the tibolone group during the entire follow-up period. Both E2?+?NETA and tibolone treatments induced an increase in progesterone levels (p?<?0.05) after 1 year of therapy. Allopregnanolone levels showed an increase in all estrogen-based groups, being significant after 3 months of treatment (p?<?0.01). Patients receiving tibolone showed a significant increase in allopregnanolone levels at 3 months (p?<?0.05), but lower than in the other groups. Cortisol levels decreased significantly in the TE and CEE?+?MPA groups after 6 months and 12 months of treatment, respectively. Neither tibolone nor E2?+?NETA treatments modified circulating cortisol levels. DHEA levels significantly (p?<?0.05) decreased after 6 months of TE or estrogen–progestin therapies independently of the presence or the type of progestin used. In contrast, DHEA remained stable throughout the 12 months of treatment with tibolone. The increase of allopregnanolone, a steroid with sedative and anxiolytic properties, in response to these different treatments could underlie, at least in part, the central effects that hormone replacement therapy and tibolone have on anxiety, mood and behavior. Unlike estrogen-based therapy, tibolone treatment did not reduce the DHEA milieu in the menopause, and thus did not enhance the androgen deficiency syndrome in postmenopausal women. 相似文献
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109.
IntroductionTotal hip arthroplasty is one of the most commonly performed orthopaedic procedures. Despite this, medical evidence to inform the choice of surgical approach is lacking. Currently in the UK, the two most frequently performed approaches to the hip are the posterior and the direct lateral.MethodsThis systematic review was performed according to Cochrane guidelines following an extensive search for prospective controlled trials published in any language before January 2014. Of the 728 records identified from searches, 6 prospective studies (including 3 randomised controlled trials) involving 517 participants provided data towards this review.FindingsCompared with the lateral approach, the posterior approach conferred a significant reduction in the risk of Trendelenburg gait (odds ratio [OR]: 0.31, p=0.0002) and stem malposition (OR: 0.24, p=0.02), and a non-significant reduction in dislocation (OR: 0.37, p=0.16) and heterotopic ossification (OR: 0.41, p=0.13). Neither approach conferred a functional advantage. We draw attention to the paucity of evidence and the need for a further randomised trial. 相似文献
110.
AD White M Skelton F Mushtaq TW Pike M Mon-Williams JPA Lodge RM Wilkie 《Annals of the Royal College of Surgeons of England》2015,97(8):608-612