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61.
Urinary tract infection in infants and children evaluated by ultrasound   总被引:1,自引:0,他引:1  
Kangarloo  H; Gold  RH; Fine  RN; Diament  MJ; Boechat  MI 《Radiology》1985,154(2):367-373
Fifty-nine pediatric patients with urinary tract infection (UTI) underwent renal ultrasonography, excretory urography, and voiding cystourethrography. The imaging procedures were analyzed retrospectively to determine their relative effectiveness in detecting abnormalities that might predispose the patient to UTI. Voiding cystourethrography provided valuable information, particularly the presence or absence of vesicoureteral reflux, that could not be obtained from the other procedures. Excretory urography was less specific than ultrasonography in the majority of patients, with the exception of those who had renal scarring. The authors recommended ultrasonography as the initial imaging procedure in the evaluation of children with UTI. When the sonogram is normal, excretory urography is not considered necessary, but voiding cystourethrography is thought to be essential. If sonography is abnormal, excretory urography and/or other follow-up studies are indicated.  相似文献   
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63.

Rationale

Lithium has been a standard pharmacological treatment for bipolar disorder over the last 60 years; however, the molecular targets through which lithium exerts its therapeutic effects are still not defined. Attenuation of the phosphatidylinositol signal transduction pathway as a consequence of inhibition of inositol monophosphatase (IMPase) has been proposed as one of the possible mechanisms for lithium-induced mood stabilization.

Objectives

The objective was to study the behavioral effect of the specific competitive IMPase inhibitor L-690,330 in mice in the lithium-sensitive pilocarpine-induced seizures paradigm and the forced swim test (FST).

Methods

The inhibitor was administered intracerebroventricularly in liposomes.

Results

L-690,330 increased the sensitivity to subconvulsive doses of pilocarpine and decreased immobility time in the FST.

Conclusions

It is possible that the behavioral effects of lithium in the pilocarpine-induced seizures and in the FST are mediated through the inhibition of IMPase, but reversal of the inhibitor’s effect with intracerebroventricular inositol would be an important further step in proof.  相似文献   
64.

Background  

Food frequency questionnaires (FFQs) have been validated in pregnant women, but few studies have focused specifically on low-income women and minorities. The purpose of this study was to examine the validity of the Harvard Service FFQ (HSFFQ) among low-income American Indian and Caucasian pregnant women.  相似文献   
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This paper describes the extent of the informal caregiving unit for older people who are physically or mentally frail living in private households or resident in long-term care institutions using cross-sectional analysis of survey data. A total of 1444 people aged 65 years or more registered with a general practitioner (GP) in four areas in England and, consenting to the study, were screened for mental or physical frailty. Of 1127 older subjects living at home 7% reported receiving no informal support, 15% had a paid supporter only and 78% nominated a key informal supporter who helped with defined activities of daily living of whom 650 (74%) were interviewed. Only 13% nominated more than one informal supporter. Key supporters were spouses (38%), daughters (30%), sons (9%), daughters-in-law (4%), other relatives (11%) and friends and neighbours (8%). Of 317 frail older people resident in long-term care institutions 175 (55%) received a main visitor at least once a week of whom 132 (75%) were interviewed. Main visitors were spouses (11%), daughters (36%), sons (23%), daughters-in-law (2%), other relatives (24%) and friends (4%). Qureshi & Walker's (1989) hierarchical, decision-making model for selecting informal caregivers was applied to the data and correctly identified 85% of key informal supporters and 79% of main visitors interviewed. This large-scale comprehensive survey of informal care for frail older people supports earlier small-scale localized studies highlighting the key role of spouses and daughters in the provision of informal support. Families of frail older people provide the support to maintain people at home.  相似文献   
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68.
The extended family forms the basis for orphan care and education in sub-Saharan Africa. Initial absence followed by emergence of differentials in primary school enrollment between orphans and non-orphans have been attributed to the strength and subsequent HIV/AIDS-induced breakdown of extended family orphan care arrangements. Yet, few attempts have been made to describe how these arrangements are affected by HIV/AIDS or how they relate to observed patterns of childhood outcomes by sex and orphan status. We use a combination of quantitative and qualitative data to show that maternal orphans but not paternal or double orphans have lower primary school completion rates than non-orphans in rural Zimbabwe, and that these patterns reflect adaptations and gaps in extended family orphan care arrangements. Sustained high levels of primary school completion amongst paternal and double orphans--particularly for girls--result from increased residence in female-headed households and greater access to external resources. Low primary school completion amongst maternal orphans results from lack of support from fathers and stepmothers and ineligibility for welfare assistance due to residence in higher socio-economic status households. These effects are partially offset by increased assistance from maternal relatives. These findings indicate that programmes should assist maternal orphans and support women's efforts by reinforcing the roles of extended families and local communities, and by facilitating greater self-sufficiency.  相似文献   
69.
Two epoxy materials with or without adhesively bonded hydroxyapatite (HA) coatings were studied for their biocompatibility and mechanical pushout strength using in vivo implantation in the rabbit lower femur for a duration of 10 days to 6 months. Both were two-part epoxies cured at room temperature for 24 h, with material 1 (Ampreg 26; SP Systems Limited, Cowes, UK) postcured at 110 degrees C (Tg approximately 80 degrees C) and Material 2 (CG5052; Ciba Geigy Limited, Cambridge, UK) at 125 degrees C (Tg approximately 120 degrees C). Implantation in dead rabbit bone was performed to provide mechanical baseline levels. Polymethylmethacrylate (PMMA) and conventionally HA-coated titanium alloy (Ti-6Al-4V) were used as control materials. In the biological study, different fluorescent dyes were used to label newly formed bone. After 6 weeks of implantation, results from mechanical pushout tests showed that the interfacial shear strength (ISS) values were significantly higher than for dead bones with each of the different implants (p < .01-.001). HA-coated material 2 showed a significantly higher ISS value than the uncoated material (p < .05) after 6 weeks' implantation. However, the ISS value for the uncoated material 2 was significantly higher than for PMMA controls (p < .05). No significant differences in the ISS values were shown between HA-coated materials 1 and 2 and Ti-6Al-4V on in vivo implantation for 6 weeks. Failure points of the pushout test from the three HA-coated materials were defined by scanning electron microscopy. Specimens implanted with both HA-coated epoxies were fractured within the HA-coatings or the bone, while with HA-coated Ti-6Al-4V cracked between the coating and metal implant. The percentage of bone in contact with the implant surface was obtained by image analysis which showed that there were no significant differences between different materials after short time implantation (up to 6 week). Long-term implantation of the HA-coated material 2 showed that the percentage of bone contact had increased from 52.8+/-1.1% (6 week) to 80.0+/-0.3% (3 months) (p < .01) and remained at 81.0+/-0.8% (6 months). Measurements of bone mineralization rate (BMR) showed that after 3 weeks of implantation, there were no significant differences between PMMA and uncoated materials 1 and 2. After 6 weeks, the BMRs in animals implanted with either HA-coated material 1 or 2 were significantly higher than with HA-coated Ti-6Al-4V (p < .05-.0001 in both cases), but with HA-coated material 2 was lower than with this material uncoated (p < .05-.001). No significant differences were found between the two HA-coated epoxy materials. In addition, there were always lower BMRs during the third week of implantation than other periods regardless of biomaterial implanted. The study indicated that the adhesively bonded HA-coated novel epoxy materials were superior to conventional plasma-sprayed Ti-6Al-4V implants with respect to both BMR and bone integration with the implant surfaces. Adhesively bonded HA-coated epoxy materials had similar ISS values to HA-coated Ti-6Al-4V, but the former failed within the bone and coating, while the latter showed splitting between coating and metal.  相似文献   
70.
We present a new method of registering three dimensional image volumes of the brain of a given patient acquired at different times or with different imaging modalities, or both. Registration is an essential requirement for fusing the data from the two image sets so as to either increase the available information by exploiting complementary imaging modalities, or to measure small changes over time for prognostication, disease assessment, etc. The new technique exploits an external, removable, remountable reference frame which is attached to the head. Computer vision techniques are used to determine the positions of fiducial marks in every image. The transformation required to map each image of one image volume onto the other image volume is developed using the theory of quaternions. The results indicate that the new technique is robust and practical in a clinical setting.  相似文献   
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