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91.
对睾酮及表睾酮的三甲基硅烷化进行了详细考察,找到了较好的抗氧剂巯基乙醇,确定了较好的衍生化条件,衍生化产物单一。并采用GC—MS法测定了尿中睾酮与表睾酮的比值。实验条件为:以氦为载气,SE—54熔融石英柔性毛细管柱、程序升温进行样品分离,多离子检测(MID),监测m/z432的离子。该法专属、灵敏、快速。睾酮与表睾酮比值在1:1~10:1(睾酮为20ng/μl)与相应峰面积比呈线性关系(r=0.998),最低检测限为1ng,最低检测尿药浓度为8ng/ml。 相似文献
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薄层扫描法测定黄芪生脉颗粒中黄芪甲甙含量 总被引:5,自引:0,他引:5
目的:制订黄芪生脉颗粒中黄芪甲甙含量测定方法。方法:双波长薄层扫描法,经乙酰洗涤、正丁醇提取和D101大乳吸附树脂柱层析法制备样品,以氯仿-甲醇-水(13:7:2)下层液为展开剂,检测波长为510nm,参比波长为700nm。结果:加标回收率平均为98.7%(RSD=2.0%,n=6),标准曲线r=0.9966,重复性RSD=1.4%(n=5),精密度RSD=2.0%(n=6)。结论:方法稳定、可靠 相似文献
94.
Kanbur NO Kanli A Derman O Eifan A Ataç A 《Journal of pediatric endocrinology & metabolism : JPEM》2006,19(8):979-985
The aim of this study was to investigate the relationships between dental age and bone age in Turkish adolescents with constitutional delay of growth and compare them with a group of normal, healthy adolescents. Left hand and wrist radiographs and dental panaromic radiographs of 33 adolescents (25 boys and 8 girls) aged between 10 and 16 years with constitutionally delayed growth were assessed. The control group comprised 41 healthy adolescents (24 boys, 17 girls) aged between 10 and 16 years. Bone age was determined according to Greulich and Pyle; dental age was assessed using the Demirjian method. In the control group, no statistical difference was found between chronological, bone and dental ages. In the group of adolescents with constitutional growth delay, there was no significant difference between chronological age and dental age, but the differences between dental age and bone age and between chronological age and bone age were found to be statistically significant. It was found that Demirjian's dental age assessment is a valid method for scoring dental age in Turkish adolescents. Adolescents with constitutional delay of growth had dental maturation appropriate for chronological age, but not for bone age. 相似文献
95.
The testicular scintigraphic findings of nine patients with surgically and pathologically proved torsion of the testis of over 24 hours duration are reviewed. In the delayed blood-pool images each showed the classical avascular twisted testicle with a variable peripheral rim of hyperemia. In the dynamic blood-flow phase, eight revealed a perceptible increase of vascular perfusion in the scrotal region on the affected side, in addition to the testicular radionuclide angiogram peculiarities previously described for missed testicular torsion. This pattern of perfusion was seen only in torsion of over one day duration. A low salvage probability is expected in these cases. 相似文献
96.
Omrana?PashaEmail author Shivaprasad?S?Goudar Archana?Patel Ana?Garces Fabian?Esamai Elwyn?Chomba Janet?L?Moore Bhalchandra?S?Kodkany Sarah?Saleem Richard?J?Derman Edward?A?Liechty Patricia?L?Hibberd K?Michael?Hambidge Nancy?F?Krebs Waldemar?A?Carlo Elizabeth?M?McClure Marion?Koso-Thomas Robert?L?Goldenberg 《Reproductive health》2015,12(Z2):S11
Background
During the post-partum period, most women wish to delay or prevent future pregnancies. Despite this, the unmet need for family planning up to a year after delivery is higher than at any other time. This study aims to assess fertility intention, contraceptive usage and unmet need for family planning amongst women who are six weeks postpartum, as well as to identify those at greatest risk of having an unmet need for family planning during this period.Methods
Using the NICHD Global Network for Women’s and Children’s Health Research’s multi-site, prospective, ongoing, active surveillance system to track pregnancies and births in 100 rural geographic clusters in 5 countries (India, Pakistan, Zambia, Kenya and Guatemala), we assessed fertility intention and contraceptive usage at day 42 post-partum.Results
We gathered data on 36,687 women in the post-partum period. Less than 5% of these women wished to have another pregnancy within the year. Despite this, rates of modern contraceptive usage varied widely and unmet need ranged from 25% to 96%. Even amongst users of modern contraceptives, the uptake of the most effective long-acting reversible contraceptives (intrauterine devices) was low. Women of age less than 20 years, parity of two or less, limited education and those who deliver at home were at highest risk for having unmet need.Conclusions
Six weeks postpartum, almost all women wish to delay or prevent a future pregnancy. Even in sites where early contraceptive adoption is common, there is substantial unmet need for family planning. This is consistently highest amongst women below the age of 20 years. Interventions aimed at increasing the adoption of effective contraceptive methods are urgently needed in the majority of sites in order to reduce unmet need and to improve both maternal and infant outcomes, especially amongst young women.Study registration
Clinicaltrials.gov (ID# NCT01073475)97.
Obstetricians-gynecologists often have a special and long-term relationship with their patients and are ideally placed to assess their fracture risk and to institute appropriate therapy for osteoporosis. Assessment of risk factors according to the World Health Organization and more recent guidelines (e.g., age, smoking history, previous fracture, parental fracture, corticosteroid use, weight) enables the clinician to target patients for testing of bone mineral density by techniques such as dual-energy x-ray absorptiometry at the proximal femur. The current therapy of choice is an oral bisphosphonate, which has proven efficacy in increasing bone mineral density, reducing bone-turnover markers, and reducing fracture rates. Their main drawback is inconvenient dosing requirements, which necessitates taking the drug in the morning at least 30 minutes before the first meal or drink of the day; this may contribute to poor adherence with therapy and suboptimal outcomes. The availability of daily or weekly (alendronate and risedronate) or monthly (ibandronate) bisphosphonates means that patients can have therapy at their preferred frequency, and along with education regarding lifestyle issues such as nutrition, exercise, smoking, and alcohol use, and measures to reduce tripping in the home, should reduce the prevalence of osteoporotic fractures. Target Audience: Obstetricians & Gynecologists, Family Physicians Learning Objectives: After completion of this article, the reader should be able to recall that there are high-risk fracture patients, explain that Ob/Gyn physicians should target their diagnostic and treatment options to these patients, and state that there are ways that increase compliance to recommended bisphosphonates in addition to the recommended lifestyle changes. 相似文献
98.
W Oh DK Stevenson JE Tyson BH Morris CE Ahlfors G Jesse Bender RJ Wong R Perritt BR Vohr KP Van Meurs HJ Vreman A Das DL Phelps T Michael O’Shea RD Higgins 《Acta paediatrica (Oslo, Norway : 1992)》2010,99(5):673-678
Objectives: To assess the influence of clinical status on the association between total plasma bilirubin and unbound bilirubin on death or adverse neurodevelopmental outcomes at 18–22 months corrected age in extremely low birth weight infants. Method: Total plasma bilirubin and unbound bilirubin were measured in 1101 extremely low birth weight infants at 5 ± 1 days of age. Clinical criteria were used to classify infants as clinically stable or unstable. Survivors were examined at 18–22 months corrected age by certified examiners. Outcome variables were death or neurodevelopmental impairment, death or cerebral palsy, death or hearing loss, and death prior to follow‐up. For all outcomes, the interaction between bilirubin variables and clinical status was assessed in logistic regression analyses adjusted for multiple risk factors. Results: Regardless of clinical status, an increasing level of unbound bilirubin was associated with higher rates of death or neurodevelopmental impairment, death or cerebral palsy, death or hearing loss and death before follow‐up. Total plasma bilirubin values were directly associated with death or neurodevelopmental impairment, death or cerebral palsy, death or hearing loss, and death before follow‐up in unstable infants, but not in stable infants. An inverse association between total plasma bilirubin and death or cerebral palsy was found in stable infants. Conclusions: In extremely low birth weight infants, clinical status at 5 days of age affects the association between total plasma bilirubin and death or adverse neurodevelopmental outcomes at 18–22 months of corrected age. An increasing level of UB is associated a higher risk of death or adverse neurodevelopmental outcomes regardless of clinical status. Increasing levels of total plasma bilirubin are directly associated with increasing risk of death or adverse neurodevelopmental outcomes in unstable, but not in stable infants. 相似文献
99.
100.