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991.
Whole blood cryopreservation in epidemiological studies. 总被引:1,自引:0,他引:1
Richard B Hayes Craig O Smith Wen-Yi Huang Yvonne Read William C Kopp 《Cancer epidemiology, biomarkers & prevention》2002,11(11):1496-1498
Standardized and cost-effective biological sample collection, processing, and storage procedures are needed in large-scale epidemiological studies to provide material for testing a broad range of etiological hypotheses. One component of sample collection in the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial involves shipment of blood in acid-citrate-dextrose anticoagulant to a central processing laboratory, where 10% DMSO is added, and whole blood aliquots are cryopreserved. A single technician is able to routinely process 50-60 samples/day. Tests conducted to evaluate potential uses of cryopreserved whole blood showed successful EBV transformation (>90%, up to 20 months of storage). In addition, lymphocytes maintained good viability and stable T-cell:B-cell ratios, and T cells maintained the capacity to proliferate in response to solid phase anti-CD3/CD28 plus interleukin 2. Whole blood cryopreservation is a cost-effective approach to large-scale storage of viable cells in epidemiological studies. 相似文献
992.
Primary bovine mammary cells express the two IGF receptors (IGF-IR, IGF-IIR),4 insulinreceptor, and four IGFBPs (IGFBP-2, -3, -4, and -5). Examination of the IGF-IR during themammary gland lactation cycle shows that IGF-IR number declines at parturition, a changethat coincides with decreases in the blood level of its ligand, IGF-I. IGF-II and IGF-IIR arelargely unchanged. IGFBP-3 is the predominant mammary IGFBP and its concentration alsodeclines in blood and milk during lactation compared to prepartum and involution periods.Time of lactation and pregnancy were the main determinants of milk but not bloodIGFBP-3 levels. IGFBP-3 binds to membrane proteins of bovine mammary tissue; an IGFBP-3 bindingprotein has been identified as bovine lactoferrin. Lactoferrin has the capacity to compete withIGF binding to IGFBP-3. Appearance of both IGFBP-3 and lactoferrin in conditioned mediaof primary cultures of bovine mammary cells was stimulated by all trans retinoic acid (atRA).Furthermore, atRA was necessary for the entry of exogenously added lactoferrin into themammary cell nucleus, while IGFBP-3 entry into the nuclei of atRA treated cells requiredthe presence of lactoferrin. These findings reveal a novel role for lactoferrin, suggesting thatlactoferrin is critically involved in the regulation of the IGF system during the involution period. 相似文献
993.
White PF Ghoname EA Ahmed HE Hamza MA Craig WF Vakharia AS 《Anesthesia and analgesia》2001,92(2):483-487
The analgesic response to percutaneous neuromodulation therapy (PNT) is influenced by the location, frequency, and duration of electrical stimulation. We evaluated the effect of different patterns of stimulation (montages) on the acute analgesic response to PNT when applied at the same dermatomal levels in 72 consenting patients with low back pain. All of the patients received a standardized montage (I) and three alternative montage (II-IV) patterns according to a randomized, single-blinded, crossover study design. All of the PNT treatments were administered at identical alternating stimulation frequencies of 15 and 30 Hz for a period of 30 min, three times per week for two consecutive weeks, with 1 wk "off" between each modality. Pretreatment assessments included the health status survey short form (SF-36) questionnaire, as well as visual analog scale scores for pain, physical activity, and quality of sleep (with 0 = the best to 10 = the worst). The pain visual analog scale was repeated 5--10 min after each treatment session. The daily oral analgesic usage was recorded in a patient diary. All four montages produced significant improvements in pain (42%--64%), physical activity (35%--51%), and quality of sleep (28%--46%), as well as 23% to 47% reductions in the daily oral analgesic usage. However, Montage II was significantly more effective than the standard (Montage I) and the other two montages studied. These data suggest that the pattern of stimulation (i.e., montage) can influence the acute analgesic response to PNT. 相似文献
994.
PURPOSE: We developed and tested the reliability of a new, structured, parent administered questionnaire to determine the prevalence of and risk factors for daytime urinary incontinence in children. MATERIALS AND METHODS: A new questionnaire was developed and evaluated in a pilot study for ease of understanding and acceptability. It was then tested for reproducibility of responses in a randomly selected sample of new primary school entrants in Western Sydney 4 weeks after baseline data were collected. The questionnaire obtained data on demographics, prevalence of daytime incontinence, family history of incontinence, voiding symptoms and socioeconomic status. Categorical data agreement was assessed using the kappa statistic and continuous data agreement was analyzed using the Bland-Altman method. RESULTS: A total of 166 subjects 3.5 to 7 years old (mean and median ages 5.6 and 5.7, respectively) completed the repeat questionnaire with a 78.5% response rate. Mean agreement of the responses to the first and second questionnaires was 91% (range 83% to 100%, mean kappa = 0.70, range 0.34 to 1.00). For continuous data the 95% confidence limits were narrow (0.3 for birth weight data). CONCLUSIONS: We have developed a new daytime urinary incontinence questionnaire using parent reported data and demonstrated that it is reproducible. We consider it to be a useful instrument for ascertaining information on urinary incontinence and other voiding symptoms. 相似文献
995.
996.
Multiple Intrapulmonary Arteriovenous Fistulas in Childhood 总被引:1,自引:0,他引:1
Pulmonary arteriovenous fistulas (AVFs) are a rare but recognized cause of cyanosis in childhood. Lesions may be acquired
as in hepatopulmonary syndrome or they may be congenital, particularly in association with certain multisystem disorders.
Large fistulas are more common than multiple small connections. Two cases, both boys, presenting in the first decade of life
are described. ``Bubble' echocardiography was the most telling investigation and strongly suggested the presence of AVFs
in both cases. Each patient then underwent cardiac catheterization, which demonstrated normal pulmonary artery pressure and
diffuse pulmonary telangiectasis. Both patients were treated effectively with nifedipine and continue with this mode of therapy. 相似文献
997.
Craig ME Howard NJ Silink M Chan A 《Journal of pediatric endocrinology & metabolism : JPEM》2000,13(4):363-372
OBJECTIVES: 1. To determine the incidence of type 1 (insulin dependent) diabetes in children aged 0-14 years who were resident in the state of New South Wales, Australia over the period 1992-1996. 2. To analyse the trends in incidence over the period 1990-1996. METHODS: Primary ascertainment of patients was performed using a prospective incidence register established in 1990. The secondary source of ascertainment was the National Diabetes Supply Scheme, a government subsidised scheme for diabetic supplies. RESULTS: There were 1,230 patients identified over the five-year period. Using the capture-recapture method, ascertainment was estimated to be 99% complete. The lowest incidence occurred in 1992 (16.9 per 10(5) person years) and the highest incidence was in 1995 (21.7 per 10(5)). The crude incidence of IDDM from 1990-1996 was 17.8 per 10(5) and there was a statistically significant rise in the incidence of type 1 diabetes over this period (p=0.0003). The annual incidence has increased on average by 3.2% per year since 1990. CONCLUSION: The incidence of childhood type 1 diabetes in NSW has increased significantly since 1990. 相似文献
998.
We report nine cases of severe early pertussis in infants less than 7 weeks of age. Clinical features at this age are atypical
and may be confused with more common illnesses such as bronchiolitis. All were very difficult to manage. Ventilation was required
for apnoeas in five cases, seizures in two or respiratory failure in two. Complications included hypotension in seven cases,
pulmonary hypertension in one, pneumothoraces in two, seizures in five and co-infection in five. Two cases were referred for
extracorporeal membrane oxygenation and six died. Infection was confirmed either at post mortem or by culture from pernasal
swabs. The mother or other close family members were symptomatic at the time and thought to be the source of infection.
Conclusion The nine cases suggest a significant resurgence of the infection, which may be fatal in early life. If reporting continues
to increase, the immunisation schedule will need to be reviewed and secondary transmission prevented where possible, to protect
this vulnerable pre-immunisation group.
Received: 5 October 1999 / Accepted: 22 May 2000 相似文献
999.
1000.
In this study, 196 young adolescents who reported that they bullied their peers were identified out of a sample of 1,758 students in Grades 5 through 8. After selecting from the total sample a group of nonbullying youth who were matched on gender, school, and grade, a comparison was made of the groups' dating experiences, quality of friend and boyfriend or girlfriend relationships, and acts of physical and social aggression. The results indicated that bullies started dating earlier and engaged in more advanced dyadic dating than comparison adolescents. Bullies were highly relationship oriented, yet their views of their friends and boyfriends or girlfriends were less positive and less equitable than the comparison adolescents. Finally, bullies were more likely to report physical and social aggression with their boyfriends or girlfriends. Although the bullies reported more advanced pubertal development, this factor did not fully account for their dating precocity and negative romantic relationships. The results confirmed our hypotheses that adolescents whose peer relationships are characterized by bullying are at risk in their development of healthy romantic relationships. 相似文献