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111.
Sixteen patients with suspected cerebral metastases were studied with magnetic resonance (MR) imaging before and after the intravenous administration of 0.1 mmol/kg of gadolinium diethylenetriaminepenta-acetic acid. The images were interpreted blindly by two neuroradiologists; all clinical, radiologic (computed tomographic and MR imaging), and pathologic data were reviewed to arrive at a final "best diagnosis," which was then compared with the prior blinded interpretations. Of seven patients found to have multiple metastases, six (86%) had at least one tumor nodule depicted by postinfusion MR imaging that was missed by one or both observers on review of preinfusion images alone. Lesions missed on preinfusion studies were usually small nodules hidden by or not detected next to regions of high-signal edema thought to be related to the adjacent tumor nodule. The authors believe that contrast enhancement improves detection of metastatic foci with MR imaging and that the findings indicate broader implications for the detection of multiple lesions from other causes.  相似文献   
112.
Four patients with proved osteopetrosis (three with the infantile malignant form and one with the benign form) were examined with magnetic resonance imaging at 1.5 T. All patients were studied in the coronal and sagittal planes using both short and long repetition time/echo time sequences. The infantile malignant form was characterized by a complete lack of signal from the marrow alternating with a signal intensity equivalent to that of the intervertebral disks, resulting in a "stepladder" appearance. In the benign form or after successful marrow transplantation in the infantile malignant form, intermediate or high signal intensity in the vertebrae was noted, suggesting the presence of some marrow elements.  相似文献   
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This paper describes the establishment of faculties of medical library and information science in four of the national medical universities in the People's Republic of China. These faculties were established in the mid-1980s, and each is fully integrated into its university. Students receive three years of non-clinical medical training followed by two years of training in library and information science. The first students to follow this five-year curriculum will graduate in 1992.  相似文献   
116.
Transmission of Ovine Herpesvirus 2 in Lambs   总被引:4,自引:1,他引:4       下载免费PDF全文
The pattern of acquisition of ovine herpesvirus 2 (OHV-2) infection in lambs was examined by a competitive-inhibition enzyme-linked immunosorbent assay and PCR. Newborn lambs (n = 118) did not exhibit antibody at birth. Viral DNA in peripheral blood leukocytes was detected in only 3% (n = 77) of newborn lambs before suckling. After nursing, viral DNA was sporadically present in about 10 to 20% of lambs until about 3 months of age. Thereafter, strong DNA signals began to appear in increasing numbers of lambs, reaching 100% by 5.5 months of age. Viral DNA in nasal secretions began to be detectable in about 30% of lambs at 5.5 months of age, achieved significant levels in 88% of lambs by 7.5 months of age, and then declined. The kinetics of the humoral immune response in lambs paralleled those of viral DNA in nasal secretions but did not parallel its presence in blood leukocytes. In the experiment to define the time of infection of OHV-2 in lambs, all five lambs separated from the flock at 2.5 months of age remained uninfected until the termination of the experiment at 1 year of age. In contrast, lambs weaned at 2.5 months of age and returned to the flock had become infected at 3.5 months of age. Weaning and separation from the flock at 3.5 months of age did not prevent infection. The study showed that OHV-2 infection does not commonly occur in perinatal lambs and that OHV-2-free sheep can be established by separation of lambs at the proper time, which has important implications for potential control measures.  相似文献   
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Objectives

We explored mothers' and clinicians' experiences of a video feedback intervention adapted for perinatal ‘personality disorder’ (VIPP-PMH) and the acceptability of a randomised controlled trial (RCT) examining its effectiveness.

Design

In-depth qualitative interviews with participants from a two-phase feasibility study of the VIPP-PMH intervention. Participants were mothers experiencing enduring difficulties in managing emotions and relationships, consistent with a ‘personality disorder’, and their 6- to 36-month-old children.

Methods

Forty-four qualitative interviews were conducted, including all nine mothers receiving VIPP-PMH during the pilot phase, 25 of the 34 mothers participating in the RCT (14 allocated to the VIPP-PMH arm and 9 from the control arm), 11 of the 12 clinicians delivering VIPP-PMH and one researcher. Interview data were thematically analysed.

Results

Mothers described feeling motivated to take part in the research and understood the need for randomisation. Research visits were largely experienced positively, with some suggestions for improvement in questionnaire timing and accessibility. Almost all mothers initially felt anxious about being filmed, but reported positive experiences of the intervention, particularly valuing its non-judgemental, positive and child-focussed nature, their supportive relationship with the therapist and the insights they gained on their child.

Conclusions

The findings indicate the likely feasibility and acceptability of undertaking a future definitive RCT of the VIPP-PMH intervention in this population. In designing a future trial, a positive and non-judgemental therapeutic relationship will be important to allay mothers' anxieties about being filmed, and careful consideration should be given to the timing and accessibility of questionnaires used.  相似文献   
120.
High turnover rates among hospital nurses demand rigorous and valid processes of research to determine the reasons motivating such attrition. In most hospitals, the exit interview often provides the only relevant data. The case study reported here examines the relative effectiveness of exit interviews and an employee attitude survey in generating data that are useful in managing nurse retention. The conclusion reached is that the attitude survey generates more data and higher-quality data. Further, the study shows that the use of open-ended questions can provide useful information and probably should be the starting point in developing or supplementing an attitude survey for nurses. Recommendations for improving the usefulness and validity of nurse attitude surveys and exit interviews in managing nurse retention are provided.  相似文献   
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