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31.
Immunization of neonatal dogs with a conjugate of 2,4-dinitrobenzene and ovalbumin (DNP2-OA), using aluminum hydroxide as the adjuvant, elicited long-lasting (over 30 wk) anti-DNP and anti-OA IgE antibody responses of high titers as determined by homologous passive cutaneous anaphylaxis. Low antigen doses of 10 or 50 μg were more effective than the higher doses of 250 or 1,250 μg in inducing high IgE antibody levels. However, this method of immunization failed to elicit any detectable IgE antibody response in adult dogs. Bronchoprovocation with antigen of sensitized animals having IgE antibody titers in excess of 64 resulted in a marked increase in airflow resistance, which could be corrected by the administration of nebulized isoproterenol. On the other hand, sensitized animals with IgE antibody titers in the order of 64 did not manifest significant bronchoconstriction on inhalation challenge but developed anaphylaxis following intravenous injection of the antigen.  相似文献   
32.
BACKGROUND/AIMS: CD10 (CALLA) has recently been reported to be expressed in spindle cell neoplasia, and has been used to differentiate endometrial stromal sarcoma from leiomyoma and leiomyosarcoma. In the breast, myoepithelial cells express CD10, but there are few studies of the expression of CD10 in mammary fibroepithelial lesions. METHODS: Stromal CD10 expression was studied in 181 mammary phyllodes tumours (102 benign, 51 borderline malignant, and 28 frankly malignant) and 33 fibroadenomas using immunohistochemistry, to evaluate whether differences in expression correlated with the degree of malignancy. RESULTS: There was a progressive increase in the patients' age and tumour size, from fibroadenoma to phyllodes tumours with an increasing degree of malignancy (p < 0.001). Stromal CD10 expression was positive in one of 33 fibroadenomas, six of 102 benign phyllodes tumours, 16 of 51 borderline malignant phyllodes tumours, and 14 of 28 frankly malignant phyllodes tumours. The difference was significant (p < 0.001) and an increasing trend was established. Strong staining was seen in subepithelial areas with higher stromal cellularity and activity. Stromal CD10 expression had a high specificity (95%) for differentiating between benign lesions (fibroadenomas and benign phyllodes tumours) and malignant (borderline and frankly malignant) phyllodes tumours. CONCLUSIONS: CD10 may be a useful adjunct in assessing malignancy in mammary fibroepithelial lesions.  相似文献   
33.
BackgroundSevere acute respiratory syndrome (SARS) and coronavirus disease 2019 (COVID-19) are closely related. The effect of AKI on the clinical outcomes of these two conditions is unclear.MethodsThis retrospective, territory-wide cohort study used an electronic public healthcare database in Hong Kong to identify patients with SARS or COVID-19 by diagnosis codes, virologic results, or both. The primary endpoint was a composite of intensive care unit admission, use of invasive mechanical ventilation, and/or death.ResultsWe identified 1670 patients with SARS and 1040 patients with COVID-19 (median ages, 41 versus 35 years, respectively). Among patients with SARS, 26% met the primary endpoint versus 5.3% of those with COVID-19. Diabetes mellitus, abnormal liver function, and AKI were factors significantly associated with the primary endpoint among patients with either SARS or COVID-19. Among patients with SARS, 7.9%, 2.1%, and 3.7% developed stage 1, stage 2, and stage 3 AKI, respectively; among those with COVID-19, 6.6%, 0.4%, and 1.1% developed stage 1, stage 2, and stage 3 AKI, respectively. In both groups, factors significantly associated with AKI included diabetes mellitus and hypertension. Among patients with AKI, those with COVID-19 had a lower rate of major adverse clinical outcomes versus patients with SARS. Renal function recovery usually occurred within 30 days after an initial AKI event.ConclusionsAKI rates were higher among patients with SARS than those with COVID-19. AKI was associated with major adverse clinical outcomes for both diseases. Patients with diabetes mellitus and abnormal liver function were also at risk of developing severe consequences after SARS and COVID-19 infection.  相似文献   
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Five major objectives for pharmacokinetic investigations in support of toxicity studies are identified as follows: Assess whether animals exhibited measurable blood concentrations in a dose-dependent manner; estimate average area under the concentration- time curve (AUC)and maximal concentration (C max )for each treatment group; elucidate general patterns in the concentration-time (CxT)profile, and summarize relationships between CxTand treatment group; determine CxTdependence on day into study; and judge interanimal variability and identify any animals with unusual concentration response. Such objectives are generally addressed in rodent toxicity studies by including satellite animals in the study. Satellite animals are extra animals dosed as per protocol but not subjected to toxicological and pathological observations and tests. Instead, they are used exclusively for the evaluation of pharmacokinetic characteristics of the test compound. In this paper, methods are described for achieving the five listed pharmacokinetic objectives in rodent toxicity studies without the use of satellite animals. A rat toxicity study is presented as an example.  相似文献   
36.
The aim of this study was to compare the linear growth of children with cerebral palsy (CP) with that of children without CP. The segmental lengths (humerus, ulna, femur, tibia, and spine), recumbent length, body weight, and bone age of 62 children with CP (age range 2.25 to 14 years, mean 7.13 years) were measured and compared with 68 children without CP (age range 1.50 to 12.67 years, mean 6.73 years). The results show that bone-age delay is common in children with CP (68% with a delay of more than 1 year). The linear growth of children with CP is similar to that of children without CP when bone age is used instead of chronological age. There is a strong correlation between segmental lengths and body height. Hence, this study favours using segmental lengths for estimating height in children with CP and using the comparison group as a reference for this purpose. Nutritional and non-nutritional factors on bone-age delay are discussed.  相似文献   
37.
PURPOSE: To determine whether molecular genetic analysis of ocular-adnexal lymphoid tumors, combined with histopathology and tumor location, is helpful in predicting which patients will develop systemic lymphoma. METHODS: A combined retrospective and prospective study of 77 patients with ocular-adnexal lymphoid tumors was performed. The tumors were subdivided into conjunctival, orbital, and eyelid lesions, and all were studied using both routine histopathology and molecular genetic analysis. RESULTS: Most lesions (70%) were small cell lymphomas of the mucosa-associated lymphoid tissue type, and the majority of tumors (90%) contained monoclonal or oligoclonal populations of lymphocytes discovered on molecular genetic analysis. Additionally, 72% of tumors exhibiting clonality had more than one gene rearrangement. Fifty-three percent of patients developed extraocular lymphoma sometime during the course of their disease. Patients with gene rearrangements on Southern blot hybridization had a 52% incidence of nonocular disease, compared with 63% of those without rearrangements. Patients with conjunctival tumors had a 37.5% incidence of nonocular disease, those with orbital tumors had a 54% incidence, and those with eyelid tumors had a 100% incidence of nonocular lymphoma. Only two patients died as result of systemic lymphoma. CONCLUSIONS: Most ocular-adnexal lymphoid tumors are lymphomas of the mucosa-associated lymphoid tissue type. The majority of tumors exhibit gene rearrangements on molecular genetic analysis, and this technique was not helpful in predicting which patients would develop nonocular lymphoma. Tumor location did have predictive value: Conjunctival lesions had the lowest incidence of nonocular lymphoma, and lid lesions had the highest incidence. Even with disseminated disease, most patients have a favorable prognosis with treatment.  相似文献   
38.
39.
AIM: To evaluate the role of magnetic resonance imaging (MRI) for staging local disease and lymph node metastases in papillary carcinoma of the thyroid by comparing MRI with ultrasound (US) of the neck. MATERIALS AND METHODS: Fourteen patients with papillary carcinoma underwent MRI and US. The images were prospectively reviewed for (1) identification of the primary lesion; (2) presence of multifocal thyroid disease; (3) extracapsular extension; (4) invasion into the trachea, oesophagus and major vessels; and (5) presence of lymph node metastases. Correlation was made with the surgical findings. RESULTS: The site of the primary lesion was correctly identified by US in 14 of 14 (100%) and by MRI in 13 of 14 (93%) of patients. Multifocal thyroid tumour was correctly identified by US in two of two patients (100%) and by MRI in zero of two (0%). Extracapsular extension (n = 9), oesophageal invasion (n = 1) and tracheal invasion (n = 2) were identified by MRI in seven, zero, and one, and by US in six, zero and zero patients, respectively. Invasion of the major vessels was not seen. Metastatic cervical nodes were present in 19 nodal groups in 10 patients involving the internal jugular chain (n = 10), posterior triangle (n = 4) supraclavicular fossa (n = 1) and central group (n = 4). Both MRI and US failed to identify metastatic nodes in the central group but correctly identified 14 of the 15 nodal groups outside the central group. CONCLUSION: Ultrasound should be used as the first line of investigation for detecting the primary lesion, multifocal disease and cervical lymphadenopathy. In cases where the primary tumour is not surrounded by normal thyroid tissue MR imaging should be added to assess extracapsular spread, especially into the trachea.  相似文献   
40.
Skin tumors induced in mice by initiation-promotion (2 microg DMBA-2 microg TPA) protocols were found to be under multigenic control. Eighty- one N2 mice from the cross (BALB/cAnPt x SENCARA/Pt)F1 x SENCARA/Pt that were either solidly resistant (no papillomas) or highly susceptible (> or = 7 papillomas/mouse) were subjected to a 'genome scan' using 89 microsatellite markers to check for associations with susceptible and resistant phenotypes. A locus on Chr 5 (Skts4) was found to control the susceptibility of SENCARA/Pt mice and the resistance of BALB/cAnPt mice to papilloma formation. In addition, higher than expected linkage scores were seen for the markers D9Mit271, D11Mit268 and D12Mit56. Further work is required to establish whether genes determining papilloma formation are located in these regions of the genome. In general, no evidence was seen for loss of heterozygosity in microsatellite markers on Chrs 5, 9 and 11 in 17 microdissected papillomas from (BALB/c x SENCARA)F1 hybrid mice.   相似文献   
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