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81.
OBJECTIVE: Ventriculomegaly has been reported in bipolar disorder, although whether it occurs at illness onset or progresses during the course of the disorder is unknown. In addition, it is unknown whether ventriculomegaly in bipolar disorder reflects acquired volume loss or underdevelopment of periventricular structures. METHOD: Magnetic resonance imaging was used to measure the volumes of the lateral and third ventricles and periventricular structures (caudate, putamen, thalamus, hippocampus). Patients with DSM-IV bipolar disorder, 18 who were having a first episode and 17 with multiple episodes, were compared with 32 healthy subjects. RESULTS: The lateral ventricles were significantly larger in the patients with multiple-episode bipolar disorder than in the first-episode patients or the healthy subjects, even after periventricular and total cerebral volumes were taken into account. Having larger lateral ventricles was associated with a higher number of prior manic episodes. The multiple-episode patients had a smaller total cerebral volume than the healthy subjects but not the first-episode patients. The putamen was significantly larger in the first-episode patients (and nearly so in the multiple-episode patients) than in the healthy subjects, although there was no difference between patient groups. CONCLUSIONS: Lateral ventriculomegaly was greater in bipolar disorder patients who had had repeated manic episodes, but it does not appear to be secondary to small critical periventricular structures. A larger than normal striatum, which has been reported in previous studies, was observed in first-episode patients. These results support the importance of prospectively studying neuroanatomic changes in bipolar disorder.  相似文献   
82.
Breast imaging reporting and data system (BI-RADS)   总被引:14,自引:0,他引:14  
The Breast Imaging Reporting and Data System (BI-RADS) lexicon was developed by the American College of Radiology to standardize mammographic reporting. The BI-RADS lexicon defines terms to describe abnormalities on mammograms, and it defines final assessment categories that are predictive of the likelihood of malignancy. Although the lexicon is clinically useful and facilitates communication and research, there is still substantial interobserver variability in its application. Lexicons for breast sonography and breast MRI are in progress.  相似文献   
83.
Breast lesions detected on MR imaging: features and positive predictive value   总被引:13,自引:0,他引:13  
OBJECTIVE: The purpose of this study was to analyze features of breast lesions detected on MR imaging that had subsequent biopsy and to determine the positive predictive value (PPV) of these features. MATERIALS AND METHODS: Retrospective review was performed of 100 consecutive solitary MR imaging-detected breast lesions that had MR imaging-guided needle localization and surgical excision. We described lesions, using terms found in a proposed breast MR imaging lexicon. Histologic findings were reviewed. RESULTS: Carcinoma was identified in 25 lesions (25%), including ductal carcinoma in situ (DCIS) in 13 (52%) and infiltrating carcinoma in 12 (48%). Carcinoma was found in 15 (25%) of 60 masses versus 10 (25%) of 40 nonmass lesions; most malignant masses (73%) were infiltrating carcinoma, whereas most malignant nonmass lesions (90%) were DCIS. The features with the highest PPV were spiculated margin (80% carcinoma), rim enhancement (40% carcinoma), and irregular shape (32% carcinoma) for mass lesions and segmental (67% carcinoma) or clumped linear and ductal enhancement (31% carcinoma) for nonmass lesions. Visually assessed kinetic patterns were not significant predictors of carcinoma, but washout was present in 70% of infiltrating carcinomas versus 9% of DCIS lesions (p < 0.01). Carcinoma was present in 17 (19%) of 88 lesions classified as suspicious versus eight (67%) of 12 lesions classified as highly suggestive of malignancy (p = 0.001). CONCLUSION: Among MR imaging-detected breast lesions referred for biopsy, carcinoma was found in 25%, of which half were DCIS. Features with the highest PPV were spiculated margin, rim enhancement, and irregular shape for mass lesions and segmental or clumped linear and ductal enhancement for nonmass lesions. Final assessment categories were significant predictors of carcinoma.  相似文献   
84.
85.
OBJECTIVE: The purpose of this study was to determine the usefulness of the combination of percutaneous imaging-guided large-core breast biopsy and sentinel lymphadenectomy in the diagnosis and treatment of nonpalpable invasive breast cancer. MATERIALS AND METHODS: Retrospective review revealed 200 consecutive nonpalpable breast cancers diagnosed by percutaneous imaging-guided large-core biopsy and treated with surgery that included sentinel lymphadenectomy. Percutaneous breast biopsy was performed with stereotactic or sonographic guidance with an automated core needle or vacuum-assisted biopsy probe. Sentinel lymphadenectomy was performed with intradermal injection of a radioisotope and intraparenchymal injection of blue contrast agent. Technical success was defined as identification of sentinel nodes at surgery. Medical records were reviewed. RESULTS: Technical success rate was 200 (100%) of 200. In 158 (79%) of 200 cancers, sentinel nodes were tumor-free, and axillary dissection was avoided. In three (2%) of 200 carcinomas, the sentinel nodes were negative for tumor, but nonsentinel nodes suspicious on intraoperative palpation were excised and found by frozen section analysis to contain tumor. Tumor was found in sentinel nodes in 39 (20%) of 200 carcinomas; axillary dissection, performed in 31 of these 39 women, revealed additional tumor in nonsentinel nodes in seven (23%). A single surgical procedure was performed for 164 (82%) of 200 carcinomas; the breast was preserved in 191 (96%) of these 200 carcinomas. CONCLUSION: Percutaneous imaging-guided large-core breast biopsy and sentinel lymphadenectomy provide a minimally invasive approach to the diagnosis and treatment of women with nonpalpable invasive breast cancers.  相似文献   
86.
87.
A study was undertaken to determine if gut flora contribute to the pathophysiology of experimental canine heatstroke. Fifty animals in four groups were anesthetized with sodium pentobarbital (25 mg/kg) intravenously. An air temperature of 42-46 degrees C was maintained adjacent to the dog with a water-heated blanket for approximately 2 h until rectal temperatures rose to 43.5 +/- 0.4 degrees C. Animals were then cooled passively in room air (28 degrees C, 20% RH) until death or until 18 h elapsed, and were euthanized. Reduction of intestine stool and bacterial contents with antibiotics, cathartics, and enemas prior to heatstroke increased the incidence of 18-h survival from 20.0% to 70.6%; antibiotics administered after heatstroke did not alter the incidence of survival over control values. These data suggest that gut flora, presumably through endotoxemia, contribute to the evolution of heatstroke pathophysiology.  相似文献   
88.
Intracellular reduction and oxidation pathways regulate protein functionality through both reversible and irreversible mechanisms. The Cdc25 phosphatases, which control cell cycle progression, are potential subjects of oxidative regulation. Many of the more potent Cdc25 phosphatase inhibitors reported to date are quinones, which are capable of redox cycling. Therefore, we used the previously characterized quinolinedione Cdc25 inhibitor DA3003-1 [NSC 663284 or 6-chloro-7-(2-morpholin-4-yl-ethylamino)-quinoline-5,8-dione] and a newly synthesized congener JUN1111 [7-(2-morpholin-4-yl-ethylamino)-quinoline-5,8-dione] to test the hypothesis that quinone inhibitors of Cdc25 regulate phosphatase activity through redox mechanisms. Like DA3003-1, JUN1111 selectively inhibited Cdc25 phosphatases in vitro in an irreversible, time-dependent manner and arrested cells in the G1 and G2/M phases of the cell cycle. It is noteworthy that both DA3003-1 and JUN1111 directly inhibited Cdc25B activity in cells. Depletion of glutathione increased cellular sensitivity to DA3003-1 and JUN1111, and in vitro Cdc25B inhibition by these compounds was sensitive to pH, catalase, and reductants (dithiothreitol and glutathione), consistent with oxidative inactivation. In addition, both DA3003-1 and JUN1111 rapidly generated intracellular reactive oxygen species. Analysis of Cdc25B by mass spectrometry revealed sulfonic acid formation on the catalytic cysteine of Cdc25B after in vitro treatment with DA3003-1. These results indicate that irreversible oxidation of the catalytic cysteine of Cdc25B is indeed a mechanism by which these quinolinediones inactivate this protein phosphatase.  相似文献   
89.
Our aim was to determine if the height of the cup, lateralisation or the abduction angle correlated with functional outcome or survivorship in revision total hip replacement in patients with a previous diagnosis of developmental dysplasia of the hip. A retrospective investigation of 51 patients (63 hips) who had undergone revision total hip replacement was performed. The mean duration of follow-up was 119 months. Forty-one patients (52 hips) were available for both determination of functional outcome and survivorship analysis. Ten patients (11 hips) were only available for survivorship analysis.The height of the cup was found to have a statistically significant correlation with functional outcome and a high hip centre correlated with a worse outcome score. Patients with a hip centre of less than 3.5 cm above the anatomical level had a statistically better survivorship of the cup than those with centres higher than this. Restoration of the height of the centre of the hip to as near the anatomical position as possible improved functional outcome and survivorship of the cup.  相似文献   
90.
PURPOSE: There is a paucity of long-term patient reported outcome data on surgery for hypospadias. We sought to evaluate genitourinary function and satisfaction after oral mucosa graft urethroplasty (OMGU) for hypospadias. MATERIALS AND METHODS: We identified 65 patients who had undergone OMGU at our institution between 1992 and 2003, and surveyed these patients to evaluate oral health, urinary function and satisfaction with outcomes. RESULTS: We located 51 patients who had undergone OMGU, of whom 43 (84%) agreed to participate in the study. Median followup was 6.9 years. Mean study age was 15.1 years. Of the patients 47% had severe hypospadias with failed previous repair and 42% had severe hypospadias with previous first stage surgery. Oral complaints were rare and primarily cosmetic. No patient whose oral harvest was limited to the cheek (vs lip) had cosmetic complaints. Urinary spray and stream deviation were reported by 11 patients (26%) and 12 patients (28%), respectively. American Urological Association symptom scores were generally low (mean 5.6 +/- 6.0, range 0 to 21) but 7 patients (16%) had moderate symptoms and 2 (5%) had severe symptoms. Of the patients 60% were mostly satisfied or better with urinary function. Although satisfaction with penile appearance varied (51% of patients were satisfied), most patients (84%) were satisfied with the overall hypospadias care. Urinary symptom scores were significantly worse among patients who had post-OMGU complications (p = 0.004). Of these patients 38% had moderate or severe urinary symptoms, while 95% of patients without complications had mild symptoms (p = 0.01). CONCLUSIONS: Many patients report good long-term outcomes of OMGU, although a subset of patients has significant urinary and cosmetic complaints that are more prevalent in association with surgical complications.  相似文献   
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