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51.
Correlation in ages at death from familial ovarian cancer among sisters.   总被引:1,自引:0,他引:1  
The analysis of pedigrees taken from 97 of 1466 women attending a screening clinic for early familial ovarian cancer showed that there was a strong correlation in the ages at death from the disease among sisters (r = 0.68, confidence limits 0.51-0.82, P < 0.001), but not between mothers and daughters. This information can be used to help counsel women who are considering the appropriate time for more intensive screening or prophylactic oophorectomy.  相似文献   
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'Stroke units save lives', but organized care requires expert staff and regular training to be effective. However, the quality of inpatient care for stroke remains poor, and stroke education is often fragmented between the health-care professions. This review describes some national and local strategies aimed at ensuring that all patients are cared for by expert staff.  相似文献   
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NKX3.1 is a prostate-specific homeobox gene located on chromosome 8p21. In the mouse, Nkx3.1 has growth-suppressive and differentiating effects on prostatic epithelium. Mutations of the coding region of NKX3.1 were not found in human prostate cancer, failing to support the notion that NKX3.1 was a tumor suppressor gene. To study the expression o NKX3.1 protein in human tissues and prostate cancer, we derived a rabbit antiserum against purified recombinant NKX3.1. Among normal human tissues, NKX3.1 expression was seen in testis, in rare pulmonary mucous glands, and in isolated regions of transitional epithelium of the ureter. NKX3.1 was uniformly expressed in nuclei of normal prostate epithelial cells in 61 histological sections from radical prostatectomy specimens. We analyzed 507 samples of neoplastic prostate epithelium, most of which were contained on a tissue microarray that contained samples from different stages of prostatic neoplasia. We observed complete loss of NKX3.1 expression in 5% of benign prostatic hyperplasias, 20% of high-grade prostatic intraepithelial neoplasias, 6% of T1a/b samples, 22% of T3/4 samples, 34% of hormone-refractory prostate cancers, and 78% of metastases. Our data show that NKX3.1 expression is highly, but not exclusively, specific for the prostate. Loss of NKX3.1 expression is strongly associated with hormone-refractory disease and advanced tumor stage in prostate cancer (P < 0.0001).  相似文献   
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In an effort to compare different methods of instructing patients, 99 women 18-25 years of age were given computer, spoken, weitten, or no instructions for the collection of a clean voided urine specimen. The group who received computer instructions was the most uniform in its performance (P less than 0.002, F-test) and reported the fewest procedural problems (P less than 0.02, Fisher test). In addition, this group had fewer contaminating bacteria than the group who received written instructions (P less than 0.03 , Mann-Whitney test). The group who received no instructions had more bacteria (P less than 0.0001, Mann-Whitney test) than any of the other groups. The effectiveness of the computer instruction was probably related to numerous attributes, including the individualized quality of the dialogue, self-pacing, self-testing, and privacy.  相似文献   
57.
Intracellular and intercellular potentials in the early amphibian embryo   总被引:10,自引:2,他引:8  
1. Membrane constants of the closer muscle of the ghost crab, Ocypoda cursor, were determined before and after treatment in hypertonic glycerol solution and return to an artificial sea-water (A.S.W.) solution.2. Muscle contraction was abolished after return of the muscle to A.S.W.3. The membrane capacitance was reduced from 29.0 muF/cm(2) to 10.5 muF/cm(2).4. Other passive properties of the muscle membrane, not dependent on capacitance, were not changed.5. The presynaptic nerve, transmitter release, post-synaptic sensitivity to transmitter and ionic mechanisms of synaptic action were unaffected by glycerol treatment.6. More than 60% of the membrane capacitance/unit area is contributed by the complex tubular system.7. The tubular system in crustacea is necessary for excitation-contraction coupling.  相似文献   
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Computer-assisted biplane regional wall motion analysis of left ventriculography has been shown to allow accurate, reproducible identification of normal vs abnormal patients. Recently, however, it has become evident that further quantitation of the degree of regional wall motion abnormality is necessary for optimal clinical evaluation, particularly in assessing the results of “Intervention Ventriculography”. Six commonly utilized methods adapted for ease in desk-top computer analysis were tested on 58 patients with healed myocardial infarctions undergoing biplane left ventriculography. A method utilizing radial chords constructed at 30° intervals from an origin at the centre of the end diastolic long axis proved most successful in both localizing regional wall motion abnormalities and quantifying the degree of abnormality.  相似文献   
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