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排序方式: 共有211条查询结果,搜索用时 15 毫秒
91.
Breast metastases from extramammary malignancies 总被引:2,自引:0,他引:2
92.
Mammographic screening in southern California: 2 1/2-year longitudinal survey of fees 总被引:1,自引:0,他引:1
The American Cancer Society sponsored a community-wide low-cost mammographic screening project in March 1986. One of the major goals was to effect a decrease in mammographic screening fees. To evaluate the effectiveness of the project, a telephone survey of 58 facilities was conducted six times over 2 1/2 years, beginning January 1986 and at 6-month intervals thereafter. The number of facilities offering lower fees for screening than for consultative mammography increased from two with a mean fee of $50.00 in January 1986 to 16 with a mean fee of $68.71 in July 1988. The trend for differentiating screening and consultative examination fees occurred at both hospital- and office-based practices, but fees were significantly lower in the office-based practices. There was also a statistically significant increase in the number of facilities accepting self-referred patients between January 1986 (15.5% of facilities) and July 1988 (34.5%). At the time of the last survey, 60% of office-based practices were accepting self-referred patients. 相似文献
93.
94.
The anterolateral thigh (ALT) flap is becoming a popular option for reconstructing a variety of soft-tissue defects, especially in the head and neck. Thinning of the flap may extend its usefulness to situations requiring less bulk, and the successful use of this technique has previously been described in the Far East. However, similar results have not yet been produced in the West. To investigate this, it is proposed that 'one-stage thinning of the ALT flap does not disrupt the blood supply to any area of the flap skin'. A series of 10 ALT flaps were raised from Western European cadavers. The arteries of the flaps were injected with Indian ink and latex rubber, and six of the flaps were cleared by the Spalteholz technique. Patterns of dye filling were compared in full-thickness and thinned specimens, and the arterial organisation within the subcutaneous fat was studied. We saw 14 perforators in 10 ALT flap dissections. These arose from the descending branch of the lateral circumflex femoral artery in eight cases and from the transverse branch in two cases. Large branches from the perforator were seen to form an arterial plexus at the level of the deep fascia, which communicates with the subdermal plexus supplying the skin. Further branches arose from the perforator and travelled obliquely through the fat to reach the subdermal plexus. In the thinned cadaver ALT flaps, dye perfusion did not reach the distal portions of the subdermal plexus. There was reduced dye filling in comparison to the full-thickness specimens. Thinning of the ALT flap reduces arterial perfusion in cadaver specimens. This allows rejection of the null hypothesis. The fascial plexus and the oblique vessels supplying the subdermal plexus are likely to be damaged or removed during thinning. This may explain the observed reduction in subdermal-plexus filling in the thinned specimens. In the clinical setting, disruption of the arterial supply in this manner could lead to ischaemia and skin necrosis in thinned flaps. One-stage thinning of the ALT flap may not be advisable in the Western population. 相似文献
95.
96.
LW DOYLE P DAVIS A DHARMALINGAM E BOWMAN 《Journal of paediatrics and child health》1996,32(2):138-142
Objective : To determine the incremental consumption of ventilator resources associated with the improving survival rate of extremely low birthweight (ELBW, birthweight 500–999 g) infants, from the time assisted ventilation was introduced. Methodology : Cohort study of ELBW infants born in one tertiary perinatal centre (The Royal Women's Hospital, Melbourne). All ELBW infants born from 1971 to 1993 were included in the study. Inhospital survival rates and patient-days of assisted ventilation were the main outcome measures. Discrete eras of relatively stable survival rate and consumption of ventilator resources were identified. These comprised the years 1971–74, 1977–83, 1985–90, and 1992–93. Cost-effectiveness ratios (the incremental consumption of ventilator resources per additional survivor) were calculated between adjacent eras by dividing the increment in the consumption of ventilator resources by the increment in the survival rate. Results : The survival rates rose progressively between eras (6.2, 33.9, 49.1, 68.8%, respectively, as did the consumption of ventilator resources (0.1, 6.6, 16.2, 24.7 patient-days of assisted ventilation per livebirth, respectively). The cost-effectiveness ratio deteriorated initially, increasing from 23.2 to 63.5 additional patient-days of assisted ventilation per additional survivor, but then improved, falling to 43.1 additional patient-days of assisted ventilation per additional survivor in the last era. These changes were even more marked for those of birthweight 750-999 g (20.0, 63.2 to 35.9 additional patient-days of assisted ventilation per additional survivor, respectively). In contrast, the cost-effectiveness ratio was initially worse for those of birthweight 500-749 g, being three-fold higher than for the larger infants, and only improved substantially in the last era (59.8, 58.3 to 44.1 additional patient-days of assisted ventilation per additional survivor, respectively). Conclusions : The initial deterioration in cost-effectiveness ratios between successive eras probably reflected the increased availability of resources for assisted ventilation, without any other major advances in perinatal care. The improvement in cost-effectiveness in the last era reflected, in part, the increased use of antenatal steroid therapy and the introduction of exogenous surfactant to neonatal intensive care. 相似文献
97.
98.
99.
Popliteal venous aneurysm 总被引:1,自引:0,他引:1
Two new cases of popliteal venous aneurysm, confirmed with findings from venography, are added to seven previously reported cases revealed in the authors' search of the English-language literature. This rare anomaly usually shows as recurrent pulmonary emboli in patients with no underlying predisposition to deep venous thrombosis. Physical examination is usually not helpful in the diagnosis. Results of combined real-time and Doppler ultrasound should indicate the diagnosis, but venography is necessary for confirmation and further anatomic detail. Surgical treatment has been fraught with complications. Eight patients, including these two new cases, have undergone surgery, and none have had a recurrence of pulmonary embolism following surgery. 相似文献
100.
Thirty-two patients with symptoms referable to the brachial plexus were evaluated with magnetic resonance (MR) imaging. Sixteen patients had undergone concurrent computed tomography (CT). MR imaging demonstrated normal findings in 16, 12 neoplasms, three cases of trauma, and one case of possible neural edema. Of the 16 patients with normal findings on MR images, eight had CT scans that were also normal. In one patient, MR images showed that the "mass" seen on CT was actually a tortuous blood vessel. In six of the 12 cases of neoplasm in which CT scans were available, MR imaging revealed more extensive disease. In the other six cases of tumor, MR imaging provided sufficient clinical information to obviate the need for CT or any other imaging modality. MR imaging provided definitive diagnoses in the three cases of trauma without further imaging. In one patient with paresthesia, MR imaging showed high signal intensity of the nerves on T2-weighted images, which was compatible with neural edema. A concurrent CT scan was normal. 相似文献