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31.
OBJECTIVE: To determine the level of a single transverse scan of intra-abdominal fat between L1 and L5 vertebrae that best predicts intra-abdominal fat volumes. SUBJECTS: Sixteen male and seven female patients with non-insulin-dependent diabetes mellitus, aged 44-74 y. OUTCOME MEASURES: Volumes and areas from single scans of intra-abdominal fat measured by magnetic resonance imaging with a 1.5 Tesla magnetic field strength. RESULTS: Intra-abdominal fat volumes and were calculated from fat areas from eight cross-sectional transverse single scans (nine scans in eight men) of 20 mm thickness. Men and women, respectively, had mean body mass index (BMI) of 27.9 (s.d. 3.0) and 31.6 (s.d. 4.7) kg/m2, and intra-abdominal fat of 2.3 (s.d. 0.5) and 2.5 (s.d. 0.6) kg. Intra-abdominal fat area of the fourth scan (in the direction of L1 to L5) gave the highest prediction of total intra-abdominal fat both in men (r = 0.959, P < 0.001) and in women (r = 0.973, P < 0.001). The intra-abdominal fat area of the third scan gave almost as good a prediction. These third and fourth scans corresponded to L2 and L3 vertebrae. The intra-abdominal fat areas from the sixth and seventh scans, corresponded to the frequently used L4-L5 and had lower correlations with intra-abdominal fat. There were no gender differences in the prediction of volumes from areas of intra-abdominal fat. Intra-abdominal fat areas of the fourth scan explained 93% of variance (SEE = 0.14 kg) of total of intra-abdominal fat for both genders: intra-abdominal fat (kg) = 0.0108 x intra-abdominal fat area of the fourth scan (cm2) + 0.244. CONCLUSIONS: In large studies of intra-abdominal fat, using magnetic resonance imaging (MRI) or computerised tomography scanning, a single intra-abdominal fat area at the intervertebral disc between L-2 and L-3 vertebrae offers a cheaper, faster and safer method, with high prediction of total intra-abdominal fat volumes and masses.  相似文献   
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We report the results of a questionnaire sent to anaesthetists and midwives on the use of obstetric analgesia and anaesthesia in Norwegian hospitals in 1996. 95% of the 49 hospitals involved responded to the questionnaire, representing a total of 56,884 births. The use of epidural analgesia in labour varied from 0 to 25% in the different hospitals with a mean value of 15%. Epidural analgesia was much more widely used in university and regional hospitals than in local hospitals (p < 0.001). Five of the local hospitals did not offer epidural analgesia during labour at all. The combination of low-dose local anaesthetic and an opioid (either sufentanil or fentanyl) had not been introduced in nine of the hospitals (20%). The optimal use of epidural analgesia to relieve labour pain was judged to be more frequent by the anaesthetists than by the midwives (19% versus 11%, p < 0.01). In response to what factors limited the frequency of epidural analgesia, the anaesthetists specified factors related to the attitude of the midwife, and the midwives specified factors related to the anaesthetist. Only five of the hospitals provided written information on the various analgesic methods that could be employed during labour. The majority of midwives considered the analgesic methods employed on their maternity ward to be good or excellent. The frequency of Caesarean section was 12%; spinal anaesthesia was used in 55%, epidural anaesthesia in 17%, and general anaesthesia in 28% of the cases.  相似文献   
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Traditional T2-based imaging techniques are geared toward imaging long-T2 species. Traditional techniques are, therefore, not optimal in clinical situations where the information of interest lies in the short-T2 species. T2-selective RF excitation (TELEX) is a technique for obtaining a T2-based contrast that highlights short-T2 values while suppressing long-T2 values-opposite to traditional T2 contrast. Previously, TELEX has been demonstrated qualitatively to highlight only very short-T2 values (T2 approximately 0.001 s). When applied to longer T2 values (T2 > or = 0.01 s), TELEX becomes sensitive to deltaB0 non-uniformities. This restricts its application to problems in which the T2 of interest is very short. In this study, TELEX is characterized quantitatively. Furthermore, a bandwidth broadening scheme is developed that reduces the deltaB0 sensitivity of TELEX. This permits the technique to be applied to longer T2 values. The capabilities and limitations of a practical implementation of TELEX are discussed.  相似文献   
34.
STUDY OBJECTIVES: To investigate the relationship of thoracic kyphosis following tuberculosis to the development of ventilatory failure and to assess the efficacy on nocturnal noninvasive ventilatory support. DESIGN: Retrospective consecutive case series with crossover from a phase without noninvasive ventilatory support to a phase with this treatment. SETTING: The Respiratory Support and Sleep Centre, Papworth, Hospital, Cambridge, England. PATIENTS: Seven patients with thoracic kyphosis following tuberculous osteomyelitis which had been contracted by the age of 4 years were studied. Their mean age was 53 (SD 7.1) years and the mean angle of kyphosis was 113.60. All patients were in ventilatory failure. INTERVENTIONS: The patients were treated with nocturnal noninvasive ventilation with either an individually constructed cuirass shell and a negative pressure pump or nasal intermittent positive pressure ventilation using a volume preset ventilator. MEASUREMENT AND RESULTS: Each patient underwent an initial clinical assessment along with radiologic studies of the spine, pulmonary function tests, daytime arterial blood gas tensions, and overnight recordings of arterial saturation, and transcutaneous carbon dioxide tension. They were reassessed in detail at a mean of 5 years after starting ventilatory support. Symptoms, vital capacity, daytime carbon dioxide tension, and overnight oximetry had all improved following treatment. Temporary withdrawal of ventilatory support led to severe sleep fragmentation in four patients and the appearance of central apneas and hypopneas in the other three. Six of the 7 patients were alive at a mean of 5.7 years after starting nocturnal ventilation. CONCLUSION: These results show that ventilatory failure may develop, after an interval of many years, in patients with a severe thoracic kyphosis due to tuberculosis in childhood. Noninvasive nocturnal ventilatory support can control the symptoms of ventilatory failure, improve the physiologic abnormalities, and is associated with prolonged survival.  相似文献   
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Puncture and injection (usually by methotrexate) of ectopic pregnancies are relatively new modalities of treatment. Lately, these have been applied to cornual ectopic pregnancies. We describe here a proposed transvaginal ultrasound-guided puncture route, leading the needle into the cornual ectopic pregnancy, first traversing the myometrium and approaching the gestational sac from the medical aspect. After extracting the needle, there is potentially less chance for rupture and bleeding. In six of the seven injected cornual pregnancies, this technique was used without complication. The only one punctured from the lateral aspect bled and required laparoscopic intervention. This technique may enable the wider use of this treatment modality by lowering the complication rate caused by bleeding at the puncture site.  相似文献   
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OBJECTIVE: To evaluate the effect of maternal age on outcomes for IVF and GIFT in women 40 to 45 years of age. DESIGN: Retrospective. SETTING: Boston IVF, a free-standing university-affiliated IVF and GIFT unit. PATIENTS: A total of 2,931 cycles of IVF and 1,826 cycles of GIFT were analyzed in women undergoing assisted reproductive technologies (IVF or GIFT) using autologous eggs. INTERVENTIONS: Medical records of patient outcomes were reviewed. RESULTS: For patients undergoing IVF, the cancellation rate for initiated cycles showed significant differences in women aged 25 to 39 (38.3%), women aged 40 to 43 (49.5%), and women aged 44 to 45 years (69.5%). A significantly lower delivery rate per stimulation and delivery rate per retrieval was found in women aged 40 to 43 years when compared with women aged 25 to 39 years. No deliveries occurred in 59 cycles in women aged 44 to 45 years, thereby representing a significant difference when compared with both women aged 25 to 39 years and women aged 40 to 43 years. For patients undergoing GIFT, the cancellation rate for initiated cycles was significantly higher in women aged 40 to 43 (25.0%) and 44 to 45 years (31.0%) when compared with women aged 25 to 39 years (15.1%). A significantly lower delivery rate per stimulation and delivery rate per retrieval was found in women aged 40 to 43 and 44 to 45 years when compared with women aged 25 to 39 years. CONCLUSIONS: Success rates for IVF and GIFT decline significantly in women > 40 years old. Women aged > or = 44 years are unlikely to benefit from the use of IVF and GIFT.  相似文献   
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