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排序方式: 共有1439条查询结果,搜索用时 15 毫秒
1.
Adrenal disorders in pregnancy. 总被引:1,自引:0,他引:1
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Coronary artery bypass grafts: visualization with MR imaging 总被引:1,自引:0,他引:1
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Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence. 相似文献
5.
Huang Guo-Shu MD Chang Wei-Chou MD Lee Herng-Sheng MD † Taylor John A. M. DC DACBR ‡ Cheng Tiang-Yeu MD § Chen Cheng-Yu MD 《Dermatologic surgery》2005,31(6):717-719
BACKGROUND: Merkel cell carcinoma is a rare malignant neuroendocrine neoplasm characteristically arising from the dermis of sunlight-exposed skin. It rarely arises outside the skin. OBJECTIVE: We present a patient with primary Merkel cell carcinoma arising from subcutaneous fat, with no involvement of the overlying skin. We describe the clinical manifestations and magnetic resonance imaging (MRI) findings. METHODS: We report a 63-year-old woman with a primary lesion of Merkel cell carcinoma that arose from the subcutaneous fat layer of the left arm. The lesion presented as a subcutaneous nodule with intact overlying skin. MRI showed that the nodular lesion was located entirely in the subcutaneous fat layer, with no involvement of the dermis. Peritumoral infiltration around the lesion and enlarged lymph nodes deep to the lesion were noted. The patient received wide excision of the lesion with dissection of the regional lymph nodes and adjuvant radiotherapy and chemotherapy. RESULTS: Histopathologic examination confirmed the diagnosis of Merkel cell carcinoma with local lymphatic metastasis, and the lesion was completely located in the subcutaneous fat, with no involvement of the dermis. These findings were well correlated with MRI findings. CONCLUSION: Primary Merkel cell carcinoma may arise from the subcutaneous fat and present as an entirely subcutaneous lesion with intact skin. MRI is helpful to evaluate the local extension of the lesion and regional lymphatic metastasis. 相似文献
6.
表小檗碱对α受体的作用 总被引:2,自引:0,他引:2
表小檗碱(epiberberine,EB)是从湖北产黄连(Coptis chinensis Franch)中提取的一种生物碱,属苯喹嗪类原小檗碱,对其药理作用的研究资料甚少,未见其对α肾上腺素体作用的报道。资料表明,许多原小檗碱类化合物有α受体阻滞作用,为从该类化合物中选择 相似文献
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G Nieman C Ritter-Hrncirik Z Grossman L Witanowski W Clark C Bredenberg 《The Journal of thoracic and cardiovascular surgery》1990,100(1):129-133
The effect of high alveolar surface tension on alveolar epithelial permeability was studied in anesthetized closed-chest mongrel dogs. Alveolar surface tension was elevated by displacement of pulmonary surfactant from the alveolar hypophase by the aerosolized detergent dioctyl sodium sulfosuccinate (OT). After measurement of baseline hemodynamics, arterial blood gases, and airway pressure, the dogs were separated into groups: Group I inhaled a 1% solution of OT (15 mg/kg) in a vehicle of equal parts saline and ethanol; group II inhaled the same volume of vehicle without OT. The pulmonary clearance of technetium 99m diethylenetriamine-pentaacetic acid (99mTc-DTPA) (half-time in minutes) was studied immediately after aerosol (OT and vehicle) delivery and compared with that of historical control values. No change was seen in arterial blood gases and airway pressure after vehicle inhalation, whereas OT caused a marked fall in arterial oxygen tension and increase in airway pressure. Vehicle inhalation effected only a slight increase in DTPA clearance, whereas OT significantly reduced half-time over control and group II. These data suggest that high alveolar surface tension increases alveolar epithelial permeability. 相似文献
9.
The effect of positive end expiratory pressure (PEEP) on the rate of lung water accumulation with high surface tension pulmonary edema was examined. Alveolar surface tension was elevated by inhalation of 15 mg/kg of the aerosolized detergent dioctyl sodium sulfosuccinate (OT). Hemodynamic measurements, blood gases, and colloid oncotic pressures were recorded in anesthesized dogs for 2 hours after surfactant displacement and elevation of PEEP to 10 cm H2O pressure (group II; n = 10). These data were compared with those of an identical protocol that used only 5 cm H2O PEEP (group I; n = 10). Pulmonary extravascular water volume (PEWV) was measured gravimetrically at the end of the experiment. OT inhalation resulted in an immediate fall in Pao2 and rise in venous admixture (QVa/QT), with little change in colloid oncotic pressure or left atrial pressure. In group I, Pao2 and QVa/QT did not improve significantly over 2 hours, whereas both returned to near baseline in group II. PEWV was elevated in group I compared with normal PEWV (historic controls; n = 11) (6.1 +/- 0.07 - 3.6 +/- 0.01 ml/gm dry lung; p less than 0.01); however, PEWV in group II (9.1 +/- 1.0 ml/gm dry lung; p less than 0.01) was greater than in both group I and historic controls. These data indicate that high alveolar surface tension induces pulmonary edema and PEEP accelerates this edema formation. 相似文献
10.
The purpose of this pilot study was to observe both relaxed and deep breathing patterns in a convenience sample to determine the incidence of normal versus faulty patterns of respiration. These observations were then combined with respondent answers to a survey on pain history to determine if there is any correlation between faulty breathing and musculo-skeletal pain patterns. If such a correlation can be made, then we propose that clinicians working with chronic pain patients may have improved outcomes if they address and correct faulty breathing patterns. Based on this study, it is suggested to include the evaluation and treatment of faulty respiration in the rehabilitation of chronic musculo-skeletal conditions, most notably cervical pain. 相似文献