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51.
Newlin  N; Silver  TM; Stuck  KJ; Sandler  MA 《Radiology》1981,139(1):155-159
Ultrasonic features of 21 surgically confirmed pyogenic liver abscesses in 18 patients were analyzed. Typical lesions were round or ovoid with a discrete, irregular, echo-poor margin. The number and intensity of internal echoes and sound transmission were variable. Such lesions can be aspirated percutaneously for definitive preoperative diagnosis. Pyogenic liver abscesses appear to have more ragged walls and are less frequently elliptical or multilocular than abscesses elsewhere in the abdomen.  相似文献   
52.
The effects of lesions of the nucleus tractus solitarius (NTS) on pulmonary vascular pressure and pulmonary lymph flow were investigated in 6 halothane-anesthetized sheep. After lesions of the NTS were created using bilateral thermocoagulation, pulmonary artery pressure rose to 150% of baseline and remained elevated for the 3-hour duration of the experiment. Systemic and left atrial pressures did not change. Pulmonary lymph flow doubled within 2 hours; the lymph-plasma protein ratio was unchanged from baseline. Sham NTS lesions and lesions lateral to NTS produced no changes. These experiments demonstrate that lesions of the central nervous system can alter pulmonary vascular pressures and transcapillary fluid flux independently of effects upon the systemic circulation. These findings may have relevance for the understanding of neurogenic pulmonary edema in humans.  相似文献   
53.
Plasma concentrations of isosorbide dinitrate have been measured after administration of increasing doses in the range 20--100 mg as sustained-release tablets (Isoket retard) containing 20 mg to human subjects. Means of peak concentrations of 4.2 ng/ml, 13.1 ng/ml, 20.7 ng/ml, 36.8 ng/ml, and 34.9 ng/ml were measured after doses of 20 mg, 40 mg, 60 mg, 80 mg and 100 mg, respectively. In the plasma of individual subjects, peak concentrations of isosorbide dinitrate increased in proportion to the dose administered. Areas under the plasma isosorbide dinitrate concentration-time curves also increased in proportion to the dose administered. Bioavailability parameters were better correlated to the dose over the range 20--60 mg than over the range 20--100 mg.  相似文献   
54.
Thirty-seven adults with nasal polyps were assessed in a multidisciplinary fashion. It was found that 43% of patients were allergic and 57% had asthma. Performing a polypectomy did not alter lower airway flow rates. Eosinophilia was prominent in nasal secretions of both atopics and nonatopics. Histological characteristics could not distinguish the "allergic" from the "inflammatory" polyp. Immunofluorescent studies indicated an abundance of polyp IgE leading to speculation of an IgE mediated process in polyp formation.  相似文献   
55.
Ultrasound diagnosis of hydrocolpos and hydrometrocolpos   总被引:1,自引:0,他引:1  
Wilson  DA; Stacy  TM; Smith  EI 《Radiology》1978,128(2):451
  相似文献   
56.

Background  

Improved survival due to advances in neonatal care has brought issues such as postnatal growth and development more to the focus of our attention. Most studies report stunting in children born very preterm and/or small for gestational age. In this article we study the growth pattern of these children and aim to identify factors associated with postnatal catch-up growth.  相似文献   
57.
Self-injurious behaviour (SIB) is a debilitating behaviour disorder that can have life-threatening consequences. It is often exhibited in intellectually handicapped and autistic populations, and it has been modeled with pharmacological manipulations in animals. We have characterized the induction of SIB using high doses of caffeine and pemoline in rats. Caffeine only produced very mild SIB in a small proportion of the rats, when administered repeatedly at very high doses (140-185 mg/kg/day). All the caffeine-treated rats showed profound signs of caffeine-toxicity at these doses, and lower doses did not induce any self-injury. On the other hand, pemoline was effective across a range of doses (100-300 mg/kg/day), including doses that did not produce overt signs of toxicity (100-200 mg/kg/day). The topography of the tissue injury sites (tail vs. paws and ventrum) differed between caffeine and pemoline treatments, and across doses of pemoline. The speed of onset, the incidence, and the severity of SIB occurred in a dose-orderly manner across the pemoline doses, and there was substantial individual variability in the induction of SIB when a moderately high dose (200 mg/kg/day) was used. These individual differences in vulnerability to self-injure are reminiscent of the fact that some humans with specific neurobiological disorders express SIB and some individuals with those same disorders do not. Accordingly, the pemoline model of SIB may be useful to investigate the neurobiological basis of factors that contribute to etiology of SIB.  相似文献   
58.
BACKGROUND: Anal cancers are thought to arise from squamous intraepithelial lesions in the anal canal, and women infected with human immunodeficiency virus-1 (HIV) may be at higher risk of anal cancer. Our aim was to determine the prevalence of human papillomavirus (HPV)-related abnormalities of the anal canal in women and to characterize risk factors for these lesions. METHODS: We evaluated HPV-related abnormalities in 251 HIV-positive and in 68 HIV-negative women. We completed physical examinations and obtained questionnaire data on medical history and relevant sexual practices. Univariate and adjusted relative risks (RRs) and 95% confidence intervals (CIs) were computed using the Mantel-Haenszel procedure and regression techniques. All statistical tests were two-sided. RESULTS: Abnormal anal cytology, including atypical squamous cells of undetermined significance, low-grade squamous intraepithelial lesions, or high-grade squamous intraepithelial lesions (HSILs), was diagnosed in 26% of HIV-positive and in 8% of HIV-negative women. HSILs were detected by histology or cytology in 6% of HIV-positive and in 2% of HIV-negative women. HIV-positive women showed increased risk of anal disease as the CD4 count decreased (P<.0001) and as the plasma HIV RNA viral load increased (P =.02). HIV-positive women with abnormal cervical cytology had an increased risk of abnormal anal cytology at the same visit (RR = 2.2; 95% CI = 1.4 to 3.3). Abnormal anal cytology in HIV-positive women was associated with anal HPV RNA detected by the polymerase chain reaction and by a nonamplification-based test (RR = 4.3; 95% CI = 1.6 to 11). In a multivariate analysis, the history of anal intercourse and concurrent abnormal cervical cytology also were statistically significantly (P =.05) associated with abnormal anal cytology. CONCLUSIONS: HIV-positive women had a higher risk of abnormal anal cytology than did HIV-negative women with high-risk lifestyle factors. These data provide strong support for anoscopic and histologic assessment and careful follow-up of women with abnormal anal lesions.  相似文献   
59.
OBJECTIVE: To determine associations among cervical cytology, colposcopy, and biopsy in HIV-seropositive women. MATERIALS AND METHODS: HIV-seropositive women and uninfected comparison women in a multicenter prospective cohort study underwent colposcopy for protocol indications. Women were eligible if they had a cervix, satisfactory cytology, and colposcopy between October 1994 and September 1999. Cytology, colposcopic impression, and biopsy were compared using equivalent categorizations. Kappa statistics with bootstrap sampling assessed strength of associations. RESULTS: Colposcopy was performed in 978/1370 HIV-seropositive women and in 154/224 seronegative women. Biopsies were performed on 603 (44%) seropositive women at least once during 1015 colposcopy visits and on 82 (37%) seronegative women at 116 visits. The positive predictive value of cytology was 72% for seropositive women and 60% for seronegative women. The positive predictive value of colposcopy was 71% for seropositive women and 55% for seronegative women. CONCLUSION: The correlation between either cervical cytology or colposcopic impression and colposcopic biopsy was poor.  相似文献   
60.
Five patients at risk for primary central nervous system lymphoma (PCNSL) recurrence were treated with high-dose methylprednisolone (HDMP) to prevent 'trafficking' of malignant lymphocytes into the central nervous system (CNS). HDMP was chosen because of its ability to stabilize the 'blood brain barrier (BBB)'. Three men with newly diagnosed PCNSL, ages 62, 76 and 78y, whose survival was projected to be 6.6 months, began treatment after achieving complete response (CR) to initial radiation therapy alone and survived 27, 37 and 59 months after treatment. In none was death from recurrent disease in CNS but one patient did die of systemic non-Hodgkin's lymphoma (NHL) five years after PCNSL diagnosis. A 20 y old man was treated with HDMP after successful combined modality therapy and is alive 75+ months after initial diagnosis without evidence of disease recurrence. A 34 y old man relapsed after combined modality initial treatment and failed to respond to HDMP when treatment was begun after unsuccessful salvage therapy; he died of disease 12 months after initial diagnosis. There were no treatment complications. The promising results in this pilot study from the basis for a North Central Cancer Treatment Group (NCCTG) 96-73-51, a Phase 2 clinical trial of brain radiotherapy and HDMP for PCNSL patients 70y of age and older, a group of patients at high risk for toxicity from intensive combined modality therapy.  相似文献   
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