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91.
Breasts are usually only incidentally included in computed tomography (CT) scans of the abdomen and chest in spite of the fact that pathologic findings are not rare. Because postpartum women are normally healthy, they rarely require examination; therefore, the presentation of lactating breasts on a CT scan is poorly known. The most common postpartum breast feature is engorgement, which is characterized by painful swelling associated with a sudden increase in milk volume, lymphatic and vascular congestion, and interstitial edema. Its appearance on a CT scan does not seem to have been described in the literature to date. The CT picture of a lactating breast shows the enlarged gland with bilateral cord- and mass-like hyperattenuated tissue. After abrupt cessation of breast-feeding, the edema component supervenes and breast tissue may become hypoattenuated. In such cases, further ultrasound evaluation is needed. We present 3 cases of postpartum breast engorgement as seen on CT.  相似文献   
92.
BACKGROUND: Physical exercise during childhood has been shown to enhance bone mineral density, thus reducing the risk of osteoporosis. OBJECTIVE: To examine bone properties, as measured by quantitative ultrasound, in prepubertal and early-pubertal female athletes engaged in impact and nonimpact sports. DESIGN: Survey. SETTING: General community. PARTICIPANTS: Twenty-five acrobatic gymnasts, 21 swimmers, and 21 control subjects. Athletes had been training for at least 1(1/2) years. MAIN OUTCOME MEASURE: Bone speed of sound (bilateral) at the distal radius and the midtibia. RESULTS: Gymnasts were significantly shorter and lighter than swimmers and control girls (P<.001) but had a body mass index similar to that of swimmers. Adiposity was lower in athletes than in controls. Speed of sound did not correlate with measures of body size. Higher mean +/- SD radial speed of sound values (nondominant side) were observed in gymnasts (3764 +/- 104 m/s; P =.045) than in swimmers and control girls (3732 +/- 99 and 3721 +/- 83 m/s, respectively). Mean +/- SD tibial speed of sound values (nondominant side) were similar in gymnasts and swimmers (3629 +/- 87 and 3619 +/- 78 m/s, respectively) and higher in the athletic groups than in the control group (3516 +/- 127 m/s; P<.001). In all 3 groups, no differences were observed between dominant and nondominant sides in the radii or tibias. CONCLUSIONS: Physical exercise, impact and nonimpact, is related to enhanced bone properties, as measured by quantitative ultrasound. Longitudinal studies using various modes of bone evaluation are necessary to determine the long-term effect of various types of exercise on bone properties.  相似文献   
93.
OBJECTIVES: To compare propofol with ketamine sedation delivered by pediatric intensivists during painful procedures in the pediatric critical care department (PCCD). DESIGN: Prospective 15-month study. SETTING: An 18-bed multidisciplinary, university-affiliated PCCD. INTERVENTIONS: All children were randomized to the propofol or ketamine protocol according to prescheduled procedure dates. Propofol was delivered by continuous infusion after a loading bolus dose and a minidose of lidocaine (PL). Ketamine was given as a bolus injection together with midazolam and fentanyl (KMF). Repeated bolus doses of both drugs were given to achieve the desired level of anesthesia. The studied variables included procedures performed, anesthetic drug doses, procedure and recovery durations, and side effect occurrence. The patient's parents, PCCD nurse and resident physician, pediatric intensivist, and the physician performing the procedure graded the adequacy of anesthesia. MEASUREMENTS AND MAIN RESULTS: Of the 105 procedures in 98 children, PL sedation was used in 58 procedures, and KMF was used in 47. Recovery time was 23 mins for PL and 50 mins for KMF, and total PCCD monitoring was 43 mins for PL and 70 mins for KMF. Five children (10.6%) in the KMF group and in none in the PL group experienced discomfort during emergence from sedation. Transient decreases in blood pressure, partial airway obstruction, and apnea were more frequent in the PL than in the KMF sedation. All procedures were successfully completed, and no child recalled undergoing the procedure. The overall sedation adequacy score was 97% for PL and 92% for KMF (p <.05). CONCLUSIONS: Both PL and KMF anesthesia are effective in optimizing comfort in children undergoing painful procedures. PL scored better by all evaluators, recovery from PL anesthesia after procedural sedation was more rapid, total PCCD stay was shorter with PL, and emergence from PL was smoother than with KMF. Because transient respiratory depression and hypotension are associated with PL, it is considered safe only in a monitored environment (e.g., a PCCD).  相似文献   
94.
95.
Polyarteritis nodosa is a systemic vasculitis characterized by segmental necrotizing lesions of medium and small-size arteries. Rarely, the inflammatory process is isolated and involves a single organ without systemic manifestations. We describe a patient with isolated polyarteritis nodosa of the testis who presented with a testicular mass mimicking primary testicular tumor. The postoperative laboratory evaluation was negative. Long-term follow-up, without systemic treatment, showed no evidence of recurrence in the remainder of the testis or development of systemic vasculitis.  相似文献   
96.
97.
In many invertebrates, distal stumps of severed axons degenerate slowly and survive for long periods of time; this lengthy process allows the study of the physiological and structural changes involved in axonal degeneration processes. The following experiments demonstrate a reduction in EPSP amplitude, an increase in the distance between neighboring release sites, an extended duration of transmitter release, and a doubling in the average number of quanta released per stimulus at each release site. Ultrastructural examination of those stumps revealed various degrees of glial cell invasion. In the same distal stump, some axons were partially filled with glial cells, but adjacent axons could be completely filled by them. Glial cell invasion was greater at regions closer to the site of axotomy and increased as time progressed. The glia engulfing the stumps exhibited hypertrophy and changes in nuclear morphology. The nuclei of some of those glia cells were unusually close to the axonal membrane in the distal stumps. In spite of these severe morphological changes, the stumps were still capable of conducted action potentials and releasing transmitter at their synapses.  相似文献   
98.
Laser surgery for the treatment of glottic carcinomas   总被引:3,自引:0,他引:3  
PURPOSE: The standard treatment for patients with early glottic carcinoma in Israel has been radiotherapy. In recent years, encouraging results with laryngo-microscopic carbon dioxide laser surgery as a treatment for early glottic carcinoma has changed our treatment strategy. We conducted a retrospective study to investigate the results of carbon dioxide laser excisional technique for early glottic carcinoma (T1, T2). MATERIALS AND METHODS: Twenty-six had squamous cell carcinoma (SCC), (21 patients with T1 and 5 patients with T2 lesions), 3 had carcinoma in situ, (CIS) and 3 had verrucous carcinoma (VC). RESULTS: All patients were free of disease after salvage treatment at the most recent follow-up. CONCLUSIONS: Careful patient selection with endoscopic staging and strict follow-up are essential to secure good results in the treatment of carbon dioxide laser for early laryngeal carcinoma.  相似文献   
99.
目的:评估静脉注射甲基强的松龙(IVMP)对外伤性视神经病变患者的疗效。方法:回顾性分析2000-01至2007-06我院收治的16例外伤性视神经病变(TON)患者的临床资料。1g甲基强的松龙分3d静脉应用,然后口服泼尼松龙11d,并逐渐减量。记录从损伤开始到治疗开始的时间。视力变化是本研究结果的主要功能评价指标。在入院时,治疗后1,2,3d;1wk和1mo时,分别记录最佳矫正视力(BCVA)。结果:共有16例患者纳入本研究,平均年龄为30岁,其中男性14例、女性2例。引起TON的主要原因有摩托车事故(占69%),打架斗殴(占19%)和体育运动(占12%)。所有患者都表现有相对传入性瞳孔障碍。在损伤后4d内开始静脉注射甲基强的松龙,采用Snellen视力表检查视力,绝大部分(56%)患者视力提高超过3行或大于等于0.5(6/12)。在损伤后5d以上才开始用类固醇治疗,视力则没有任何进步。结论:治疗TON,静脉注射中等到大剂量甲基强的松龙仍将起到重要作用。静脉注射甲基强的松龙治疗TON可能存在伤后4d的关键时期,超过了这个时期,该治疗可能就毫无效果。但还需要有更多的研究来为我们提供有明显统计学意义的数据。  相似文献   
100.
A wide variety of definitions are used for Treatment Resistant Depression (TRD), considering various criteria and different concepts. Some of the key issues are: the diagnosis, the treatment adequacy in terms of dose and duration, the treatment response assessment and the number of failed therapeutic trials required. Systematic research has been characterizing the concept and criteria to define the different variables involved. Lack of consensus on these issues limits comparison across clinical trials and interpretation of treatment efficacy in the management of treatment resistant patients. Through reanalyzes of available data, we point out the limits of TRD definitions and propose conceptual and operational criteria for a collaborative research project on TRD. It appears that a number of variables commonly associated to treatment resistance are independent of patients characteristics and mainly refer to misdiagnosis and inadequate treatment. The proposed criteria are intended for therapeutic trials in TRD, combining the evaluation of treatment efficiency and the validation of the concept of TRD itself. Major depression with poor response to two adequate trials of different classes of antidepressants is proposed for an operational definition of TRD. Rationale for this definition is discussed in contrast to alternative definitions.  相似文献   
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