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91.
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   
92.
Three experiments were conducted to characterize the time course of amphetamine's effects on food consumption using procedures that would allow both decreases and increases in eating to be evident relative to control levels. In Experiment 1 we measured eating over 12 postinjection hr in rats. Orderly changes in within-day temporal patterns of eating over the 12 days of amphetamine administration suggest the role of conditioned adaptive processes. In Experiment 2, animals were not presented food until 2 hr after drug administration. Initial anorexia and subsequent hyperphagia were produced by repeated administration of amphetamine. Experiment 3 assessed both within-day and over-day changes in body weight and food consumption and showed that in addition to the drug's anorectic effect, amphetamine also reduces body weight via other mechanisms. In interpreting tolerance to anorectic drugs, it is necessary to evaluate such changes in body weight that indicate shifts in hunger that occur over days as well as shifts in within-day temporal patterns of eating that indicate the presence of conditioned adaptive changes. It is proposed that these two adaptive mechanisms account for pharmacodynamic tolerance.  相似文献   
93.
The relationship between fecundability and month of birth was investigated in a cohort of 1526 women who married between 1802 and 1929, using only women whose first marriage occurred before the age of 35 years. On the basis of their time to pregnancy (TTP, calculated as time between wedding and first birth minus gestational length), women were categorized into two groups: fecunds (TTP up to 12 months or prenuptial conceptions, n = 1348) and subfecunds (TTP >18 months, n = 118). By use of logistic regression, cosinor functions with a period of 1 year or 6 months and variable shift and amplitude were fitted through the monthly odds of subfecunds versus fecunds. The best fitting curve was unimodal, with a zenith in September (P = 0.13 for H0: no differences). Exclusion of childless women (n = 36, minimum follow-up 5 years) from the subfecunds led to a similar curve (P < 0.01), while childless women, as compared with fecunds, showed a birth distribution that was best represented with a bimodal curve with zeniths in January and July (P = 0.06). This study provides evidence for the existence of differences in fecundability by month of birth. The cause of this relationship is unclear, but may lie in a melatonin-dependent circannual variability of the quality of the oocyte.   相似文献   
94.
Transplacentally acquired lymphoid chimerism was detected in two infants with severe combined immunodeficiency (SCID) by two-colour cytofluorographic studies. These cells had no demonstrable function in studies in vitro. Following T cell-depleted maternal bone marrow stem cell transplantation, evidence of T cell function was detected 20 and 50 days later, and transient B cell function was detected 50 days later. These immune functions appeared much sooner than the 90-120 days usually required for T cell function and the 2-2.5 years for B cell function to develop after haplo-identical stem cell transplants into SCID infants without transplacental engraftment. The presence of maternal lymphoid chimerism did not interfere with haplo-identical marrow cell engraftment, even though no pre-transplant immunosuppression was given. This observation suggests that the transplanted maternal marrow stem cell in some way conferred reactivity on the engrafted but apparently non-functional mature T cells that had entered the fetal circulation transplacentally.  相似文献   
95.
An RT-PCR/ELISA system has been developed that detects and differentiates Rinderpest virus (RPV) from the other closely related morbillivirus of ruminants, Peste des petits Ruminants virus (PPRV). In addition, using lineage specific probes, it is possible to determine whether the virus sample is wild-type or vaccine, and the likely origin of the outbreak if it is wild-type. It involves carrying out a RT-PCR with one digoxygenin (Dig)-labelled primer followed by a hybridisation step with a virus-specific, biotin-labelled, probe. The hybridisation step is carried out in an ELISA format on a streptavidin-coated plate. The DIG-labelled products are detected using a specific anti-DIG monoclonal antibody and an anti-mouse horseradish peroxidase conjugate. The hybridisation step replaces nucleotide sequencing or nested PCR for confirmation of the identity of DNA product. The assay is fast and easy to carry out and can give semi-quantitative estimates of the virus content of samples.  相似文献   
96.
Virus infectivity in samples of culture medium or suspensions of animal tissue which are required for interferon assay can be rapidly and conveniently inactivated by overnight incubation with beta-propiolactone (BPL). As BPL hydrolyses spontaneously samples can be assayed with no further treatment. BPL does not affect the interfering activity of alpha, beta or gamma mouse interferons.  相似文献   
97.
98.
Immunoregulation in aged humans   总被引:2,自引:0,他引:2  
  相似文献   
99.
Symptomatology of late-life minor depression among primary care patients   总被引:10,自引:0,他引:10  
Patients of four general internists and four family physicians were interviewed by two psychiatrists to identify those suffering from depressive disorders. Nineteen elderly (60 years of age and older) patients and 22 younger (between 18 and 59 years of age) patients met Research Diagnostic Criteria (RDC) for minor depressive disorder, and 73 elderly and 79 younger patients had no psychiatric disorder. In general, the elderly depressed medical outpatients and the younger depressed medical outpatients had similar symptomatology, as did the elderly and nonelderly medical outpatients without psychiatric disorders.  相似文献   
100.
A rapid Spot-CAMP test was evaluated for its ability to accurately identify colonies of Streptococcus agalactiae (Lancefield Group B) growing on primary sheep blood agar plates. The test uses a beta-lysin-containing filtrate, which is prepared from a broth culture of Staphylococcus aureus. A drop of beta-lysin filtrate is applied adjacent to a suspected group B Streptococcus (GBS) colony and the plate is incubated and then examined for a zone of synergistic hemolysis. The Spot-CAMP test demonstrated 100% correlation with both a Standard CAMP procedure and Lancefield serogrouping. The rapid Spot-CAMP test was easy to perform and inexpensive, and could presumptively identify within 30 minutes colonies of GBS growing on primary isolation plates.  相似文献   
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