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1.
The mechanism of repression of the beta-glucoside utilization (bgl) operon of Escherichia coli by a carboxy-terminally truncated derivative of the nucleoid-associated protein H-NS which is defective in DNA binding was investigated. The DNA-binding function of the H-NS-like protein StpA was found to be necessary for repression, which is consistent with a role for StpA as a DNA-binding adapter for mutant derivatives of H-NS.  相似文献   

2.
To clarify the importance of imaging plane in evaluation of invasion by tumor into muscle, 50 patients with bladder tumors underwent examination with magnetic resonance (MR) imaging performed with an oblique plane and the early phase of contrast enhancement. After the ideal oblique plane was selected, an oblique T2-weighted image was obtained. Gadopentetate dimeglumine was then administered, and an oblique T1-weighted image was obtained. The staging based on oblique T2-weighted and oblique contrast material-enhanced T1-weighted MR images was then correlated with histopathologic staging. The respective accuracies of oblique contrast-enhanced T1-weighted and oblique T2-weighted images were 78% and 60% for overall staging (P < .05), 90% and 74% for differentiation between (a) stage T1 and lower-stage tumors and (b) stage T2 and higher-stage tumors (P < .05), and 92% and 88% for differentiation between (a) stage T2 and lower-stage tumors and (b) stage T3a and higher-stage tumors (P > .05). Oblique MR imaging performed in conjunction with the early phase of contrast enhancement showed significantly high staging accuracy, especially in differentiation between superficial tumors and tumors with superficial muscle invasion.  相似文献   

3.
Dynamic magnetic resonance (MR) imaging was performed on a 1.5-T superconducting unit for evaluation of 26 stage I endometrial carcinomas. To establish the appearance of the normal uterus, 27 normal uteri were also evaluated. After rapid injection of gadopentetate dimeglumine, dynamic images were obtained every 30 seconds with the spin-echo technique in the sagittal plane. On dynamic studies of endometrial carcinoma, the tumor-myometrial contrast was marked at 120 seconds after administration of gadopentetate dimeglumine (contrast-to-noise ratio [C/N], 26.0). The tumor-myometrial contrast on the dynamic study was more marked than that on postcontrast T1-weighted images (C/N, 10.0) and on T2-weighted images (C/N, 2.14). Dynamic and postcontrast MR images were superior in enabling differentiation of viable tumors from necrosis or residual secretion in the endometrial cavity. In the evaluation of presence of tumor and myometrial invasion, the accuracy of T2-weighted imaging and dynamic imaging was 67.9% and 84.9%, respectively.  相似文献   

4.
PURPOSE: Many patients with urological disease do not speak English. In medical studies restricting patients to those who speak only English undermines efforts to understand disease because restrictions decrease efficiency of patient recruitment, and because language and culture are associated with variable outcomes. In Spanish speaking locations, such as South Florida, studies would suffer severe selection bias if patients were required to speak English. To allow grouping in future studies of English and Spanish speaking patients we examined the English-Spanish reliability of select instruments that measure health related quality of life in patients with urological disease. MATERIALS AND METHODS: We assembled available Spanish versions and translated English versions of questions regarding satisfaction, the American Urological Association symptom index, the University of California, Los Angeles Prostate Cancer Index and a pain inventory. We then examined English-Spanish reliability by asking bilingual men 50 years old or older to complete English and Spanish versions at the same sitting. A convenience sample was recruited from outpatients and volunteers at the Miami Veterans Affairs Medical Center and population based subjects living in largely Hispanic Hialeah, Florida. Reliability estimates were calculated with kappa coefficients for categorical data and intraclass correlation coefficients for quantitative data. RESULTS: A total of 100 subjects a median of 59 years old completed the questionnaire, including 55 born in Puerto Rico or Cuba, while the remainder were born at various sites throughout the Americas and Spain. Reliability estimates showed that kappa = > 0.81 for almost all items. For 2 items relating to health and social interactions reliability was poor, and stratification showed that poor reliability was primarily a feature of subjects in good health who are theoretically socially active. CONCLUSIONS: Almost all items tested have excellent English-Spanish reliability in a mixed sample of bilingual men. Nonreliability of 2 items relating to health and social interactions probably originates from the effect of language on perception, and invalidates English and Spanish grouping of these items. Because the sample represents many dialects of Spanish, the translations tested may be transported to other cities. In studies that use these instruments investigators can reasonably group answers from English and Spanish speaking study subjects or study the effects of acculturation on quality of life.  相似文献   

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MR imaging of the female pelvis with a local coil (multiple phased array coils) has been reported. With this method, the signal-to-noise ratio (S/N) is improved so that high-resolution images can be obtained. Dynamic contrast-enhanced MR imaging has been reported to be useful in diagnosing uterine neoplasms. However, dynamic MR imaging is done in only limited imaging planes. When multisection dynamic MR imaging with fast gradient-echo sequences is combined with the use of a local coil, high-resolution images can be obtained throughout the entire uterus during a single breath-hold. This pictorial essay illustrates the appearance of the normal uterus and malignant uterine neoplasms on high-resolution multisection dynamic MR images obtained with a Helmholtz-type surface coil.  相似文献   

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OBJECTIVE: The purpose of this study was to show the usefulness of MR imaging with a transrectal coil (TRC) in the management of various urethral abnormalities. This report also reveals the appearance of various postsurgical changes relating to the therapy of urethral abnormality. CONCLUSION: The high-resolution images obtained with TRC MR imaging were useful in evaluating urethral abnormalities. The imaging guided therapy in most cases. In two patients, TRC MR imaging more accurately depicted abnormality than did voiding cystourethrography and transvaginal sonography. In one case, TRC MR imaging was the only imaging technique that revealed the abnormality of periurethral scarring.  相似文献   

9.
A prospective study was undertaken to clarify the relationship between postoperative morphological/pathological changes in the affected root and the clinical developments after disc resection. Gadolinium-enhanced magnetic resonance (MR) imaging was performed at 1 week, 5 weeks, 3 months, and 6 months after surgery for 28 patients of 34 consecutive patients who underwent single-level disc resection. Enhancement/thickening of the affected root was found to be 100%/89% at 1 week, 50%/57% at 3 months, and 32%/37% at 6 months after surgery. Patients with root enhancement and thickening at 3 and 6 months after surgery had less clinical improvement than patients without it. There was consistent correlation between postoperative clinical developments and nerve root enhancement/thickening in enhanced MR imaging. To use enhanced MR imaging as an evaluation tool after disc surgery might increase the diagnostic accuracy and reduce failed back surgery syndrome.  相似文献   

10.
PURPOSE: We tested the hypothesis that the histochemically demonstrated prostate specific antigen (PSA) content of prostate carcinoma cells does not necessarily reflect PSA production and secretion by evaluating expressed prostatic fluid. MATERIALS AND METHODS: Expressed prostatic fluid and serum from 152 men with clinical benign prostatic hypertrophy (BPH), 132 with histologically proved BPH and 46 with prostate carcinoma were analyzed with the Hybritech PSA assay. RESULTS: Expressed prostatic fluid PSA levels from carcinoma patients (median 1.70 mg./ml., mean 2.25) were significantly higher than in the histologically proved BPH group (median 1.28 mg./ml., mean 1.42, p < 0.05). CONCLUSIONS: PSA concentration is increased in the expressed prostatic fluid of prostates of men with carcinoma compared to those with histological BPH. This finding may be a functional manifestation of a field change or paracrine effects within the prostate.  相似文献   

11.
Methicillin-resistant Staphylococcus aureus (MRSA) is a well-recognized cause of hospital-acquired sepsis. We reviewed the clinical features of a new variant of community-acquired MRSA originally described from the Kimberley region of northern Western Australia (WA MRSA). This strain has become an increasing cause of community- and hospital-acquired sepsis at Royal Darwin Hospital (RDH) in the Northern Territory, especially in Aboriginal Australians from remote communities. Fifty percent of WA MRSA was community-acquired, with 76% in Aboriginals. Like the MRSA from eastern Australia (EA MRSA), WA MRSA commonly caused skin sepsis but was less likely to cause respiratory or urinary infections compared with EA MRSA. Twelve out of 125 (9.6%) WA MRSA and 7/93 (7.5%) EA MRSA infections were septicaemias. Septicaemia due to WA MRSA occurred in adult medical patients, especially those with temporary haemodialysis catheters, while EA MRSA septicaemia occurred throughout the hospital. Aboriginal people were more likely to develop both community- and hospital-acquired WA MRSA septicaemia [overall relative risk (RR) 12.3 (95% CI 3.7-40.7)]. Control of WA MRSA requires policies to reduce transmission in both hospitals and communities. Community-based control programmes need support for individual patient management, improved housing and hygiene, control of skin sepsis and appropriate use of antibiotics, especially in rural Aboriginal communities in northern Australia.  相似文献   

12.
OBJECTIVE: The purposes of this study were to assess the appearance of stage 1 neoplasia of the cervix by high-resolution MR imaging with an enveloping transvaginal receiver coil and to correlate the imaging findings with the pathologic findings. SUBJECTS AND METHODS: Fifteen patients (25-73 years old; mean, 40 years old) with clinical stage I disease were examined with a 37-mm-diameter ring-design solenoid receiver coil placed around the cervix. Axial 2.5-mm contiguous slices were obtained with a field of view of 10-15 cm on a 1.0-T HPQ Vista scanner with T1-weighted (660/20 msec [TR/TE]) and T2- weighted (2500/80 msec) spin-echo sequences and dynamic gradient-echo sequences during injection of gadopentetate dimeglumine (0.1 mmol/kg). Ten patients subsequently underwent Wertheim's hysterectomy, two underwent radiotherapy, two underwent extended cone biopsy for microinvasive disease, and one underwent a punch biopsy. For seven of 10 patients who had a hysterectomy, the widths of the tumor and the residual stroma were measured at eight radial points on the transverse images and at corresponding points on the histologic specimens at 5, 10, 15, 20, and 25 mm from the ectocervix. We then compared the widths of the tumor and the stroma on images and histologic specimens at each of these 40 points. Tumor volumes were calculated from the MR imaging and pathologic data and compared. For the other three patients, detailed MR imaging-pathology correlation was not possible because of multifocal tumor distribution (two patients) and insufficient detailed pathologic data (one patient). RESULTS: Three carcinoma types were recognized. Squamous carcinoma (nine cases) was seen as a centrally expanding intermediate-signal-intensity mass, whereas oat (small)-cell carcinoma (one case) and clear-cell carcinoma (one case) showed a multifocal distribution. For patients who had a radical hysterectomy, we noted good agreement between the widths of the tumor and the stroma determined by MR imaging and histology. Tumor volumes were determined to be 0-28.2 cm3 by MR imaging and 0-18.4 cm3 by pathology. We observed tumor extension into the immediate parametrium in four patients by MR imaging; one of these cases was not confirmed at surgery. Parametrial extension was not underestimated by MR imaging in any case. CONCLUSION: High-resolution imaging of the cervix with a transvaginal coil provides accurate assessment of the intra- and extracervical extents of tumors in clinical stage 1 cervical neoplasia.  相似文献   

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Rhabdomyosarcoma is the most common primary orbital malignancy of childhood. It can present insidiously, mimicking other (benign) processes clinically and radiographically. CT and MR imaging are crucial in the diagnostic evaluation, treatment planning, and follow-up monitoring of the disease. Such imaging, especially when contrast is used, can accurately detect and state the extent of tumor involvement.  相似文献   

15.
MR imaging is an essential tool for the evaluation of musculoskeletal neoplasms in children. It provides useful information for diagnosis, determination of extent of disease, assessment of response to treatment, and detection of complications and effects of therapy. This article reviews the current role of MR imaging in each of these situations. A protocol for the evaluation of these lesions is suggested. Also addressed are issues related to differentiating pathologic conditions, normal marrow, and cartilaginous structures of the pediatric skeleton.  相似文献   

16.
OBJECTIVE: To examine the effect of oxygen on apneas and sleep quality in patients with frequent central apneas during sleep. DESIGN/SUBJECTS: Prospective intervention study of 20 consecutive patients with predominant central apnea identified from 570 patients referred for suspected sleep apnea syndrome. Sixteen patients had congestive heart failure and seven of them had a previous stroke. Three of the remaining four patients without heart failure had experienced a previous stroke, and one was being treated with morphine. SETTING: The Department of Pulmonary Medicine at Ume? (Sweden) University Hospital. INTERVENTIONS: The patients were investigated for one night receiving nasal oxygen and one night without it. MEASUREMENTS: Overnight polysomnography with transcutaneous PCO2 and arterial blood gases. RESULTS: Central apneas occurred during Cheyne-Stokes respiration in 18 of 20 patients and two patients had idiopathic central apneas. Without oxygen, the median number of all central apneas and hypopneas was 33.5 (range, 8.0 to 52.0) per hour of sleep. These episodes decreased to 5.0 (range, 0.0 to 31.0)(p < 0.01) during oxygen therapy. In 17 of 20 patients, the frequency of central apneas was reduced by more than 50%. Central apneas were reduced by oxygen irrespective of the presence or absence of heart failure or Cheyne-Stokes respiration. The arousal frequency was reduced during oxygen treatment. Daytime sleepiness, difficulty falling asleep, snoring, and self-scored awakenings were reduced in seven patients who were given nocturnal oxygen at home. Obstructive and mixed apneas were unaffected by oxygen. CONCLUSIONS: Oxygen effectively reduces central sleep apnea in eucapnic patients.  相似文献   

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Spatial resolution of MRI within the true pelvis can be increased by a factor of 12 using an endorectal coil. The value of this new method for demonstrating the prostate, the rectum, the cervix and vagina and of pathological processes of these organs was examined in 89 patients and the results compared with conventional body coil MRI. In 25 patients who underwent radical surgery the results of the preoperative studies were compared with the histological findings. Detailed recognition of anatomical structures was markedly improved by using the endorectal coil. Diagnosis of carcinoma of the prostate and extension of the tumour was accurately assessed in 33 patients. Preoperative staging was correct in 87%, compared with 73% when using a body coil. The difference was less marked in examinations for carcinomas of the rectum, the cervix and vagina. Nevertheless, staging was more accurate in a few cases with a better recognition of recurrences. MRI with endorectal coils will have an important role in diagnosis of carcinomas of the prostate in the future. Its use in the diagnosis of carcinomas of the rectum and cervix must be subject to further studies.  相似文献   

19.
The last (may 1995) NHI Consensus Development Conference on cochlear implant recommends to extend the use of cochlear implant for adult patient suffering from bilateral acquired severe hearing impairment. Its indications are a severe-to-profound sensorineural hearing loss bilaterally presenting an open-set sentence recognition scores less than or equal to 30 percent under best aided conditions. We report the results of our 4 first implantees responding to these criteria, and discuss the mechanisms of the speech intelligibility improvement which has been obtained.  相似文献   

20.
The value of prostatic acid phosphatase (PAP) and prostate specific antigen (PSA) as serum markers in carcinoma of the prostate (CaP) was investigated in this study. A group of 75 patients entered this trial, 25 with CaP, 25 with benign prostatic hyperplasia (BPH) and 25 with urologic disorders other than prostatic diseases. In the CaP group, PAP was above normal levels in 48% of the patients and PSA in 92%. In the BPH group these rates were 20% and 72%, respectively. No elevation was detected in the third group. In CaP patients with capsular invasion, PAP and PSA levels were above normal in 25 and 87.5%. In metastatic carcinoma, PAP was high in 75% and PSA in 100%. Our study reveals that neither of these markers is useful in the initial diagnosis of CaP. Though PSA seems to be more sensitive, it is not more specific than PAP.  相似文献   

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