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The influence of hereditary absence of thymus and spleen upon the numbers, organ, and class distribution of background immunoglobulin Ig-secreting cells was studied in mice by means of the protein-A plaque assay. In young adult BALB/c mice the spleen contained the largest number of Ig-secreting cells (about 0.5% ). The absolute number of Ig-secreting cells in the spleen was larger than the estimate for all lymph nodes together. Between 8 and 40 weeks of age, the number of Ig-secreting cells in spleen and lymph nodes increased by a factor of 3, maximally. In the same period, the number of Ig-secreting cells in the bone marrow, however, increased by a factor of 20, so that it became the major site of Ig synthesis. Hereditary absence of the spleen did hardly or not at all affect the number of Ig-secreting cells in the other lymphoid organs. However, the athymic state did affect the organ distribution. The most consistent finding was the decreased number of Ig-secreting cells in the Peyer's patches.The class distribution of Ig-secreting cells was found to be independent of the presence of the spleen, but did depend on the presence of the thymus. Athymic mice had a higher percentage of IgM-secreting cells and a lower percentage of IgA-secreting cells. The percentage of IgG1- and IgG2-secreting cells did not differ clearly between normal and athymic mice. Percent-wise, most IgM-secreting cells occurred in the spleen, whereas most IgG1-, IgG2-, and IgA-secreting cells occurred in the bone marrow, lymph nodes, and Peyer's patches.The specificity repertoire of the background Ig-secreting cells was tested by determining the frequencies of IgM-producing cells with specificity for a panel of six different antigens. These frequencies ranged from 1 in 85 for nitroiodophenyl(NIP)-conjugated sheep erythrocytes (SRBC) till 1 in 1500 for unconjugated SRBC and were found to be the same for the spleen of germ-free and specific pathogen-free (SPF) C3H mice, and for spleen, bone marrow, and thymus of SPF C3H mice.  相似文献   
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Cholecystokinin-decreased food intake in rhesus monkeys   总被引:1,自引:0,他引:1  
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This study analyses the influence of female and male patient age and human menopausal gonadotrophin (HMG) requirements on clinical pregnancy rates and live birth rates with ovulation stimulation using HMG in combination with intrauterine insemination (IUI). In this study, 363 consecutive HMG/IUI treatment cycles in 184 patients carried out at a university fertility centre were analysed in a retrospective fashion. The main outcomes measured were clinical pregnancy rates and live birth rates. Increased female partner age (> or = 35) and male partner age (> or = 40) were found to negatively influence pregnancy rates with HMG/ IUI therapy. In addition, this study demonstrated a critical threshold of HMG requirements beyond which pregnancy did not occur. No pregnancies occurred in treatment cycles requiring > 25 ampoules (1875 IU) of menotrophins to achieve follicular maturity, irrespective of patient age. In conclusion, female partner age, male partner age, and HMG requirements all significantly influence pregnancy rates with HMG/IUI therapy.   相似文献   
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INTRODUCTION: Core biopsy of the breast has become the method of choice for tissue diagnosis of screen detected microcalcifications and some mass lesions in many breast assessment centres. Biopsy results are not available until the following day. Imprint cytology of fresh breast core samples allows same-day reporting and patient counselling.
AIM: To determine the accuracy of core imprint cytology when compared with core biopsy diagnosis when used in a breast assessment centre setting.
METHODS: Core imprints (CI) were prepared and reported on all fresh core biopsies (CB) performed at the Sir Charles Gairdner Hospital Breast Centre from May to December 2000. Fresh core samples were placed on a glass microscope slide. Core radiographs were taken for microcalcification lesions (MC). A laboratory technician gently and quickly rolled the cores on the slide with fine forceps. The cores were fixed in formalin, processed and reported next day. The imprint slide was air dried and stained with DiffQuik. CI were reported using four categories: Insufficient, Benign, Indeterminate and Malignant. Counselling and planning for management were possible on the same day in women with malignant diagnoses. Clinicians were advised not to discuss negative or indeterminate CI results with women and to defer to the final CB report.
RESULTS: Cores were performed on 381 lesions. There were 83 carcinomas (38 in MC and 45 in masses) and 56 were called malignant on CI (absolute sensitivity 67.5%; 78.9% for MC and 57.8% for masses). 3 malignancies on CB were negative on CI giving a false negative rate of 3.6%. There were no false positive diagnoses. The predictive value of a benign diagnosis was 95.3%. There were no adverse effects in the histology of CB.
CONCLUSION: CI was an accurate method of providing an immediate diagnosis of malignancy in two thirds of malignancies confirmed on CB.  相似文献   
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Adrenergic mechanisms in cerebral circulation of the goat   总被引:1,自引:0,他引:1  
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