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1.
Abstract Observations on the effect of unemployment on health include note that the clustering in certain geographic areas of low income, job insecurity and poor housing are the experience of the same groups of people. Considerable difficulties exist in isolating the different aspects involved. Nonetheless, it is argued (1) that the effects of each separate strand are dependent upon and reinforced by the others; (2) that it is possible to clarify the ways in which the elements interrelate; and (3) that it is the whole pattern that most satisfactorily explains currently available data on unemployment and health.  相似文献   
2.
Orbital exenteration at the Mayo Clinic. 1967-1986   总被引:2,自引:0,他引:2  
Orbital exenteration was performed in 102 patients at the Mayo Clinic during the 20-year period from 1967 through 1986. The surgical procedure was performed for mucormycosis in one patient and for pain and deformity after a severe facial burn in another; in the remaining 100 patients, exenteration was used to treat a neoplastic disorder. Although 19 different neoplasms were encountered, squamous cell carcinoma, basal cell carcinoma, and melanoma constituted 70% of the total. In 82 patients with no known residual tumor or metastases at operation, the 1-year survival rate was 88.6%, the 5-year rate was 56.8%, and the 5-year rate free of recurrence or metastases was 48.3%. In 18 patients with known residual tumor or metastases at exenteration, 55.0% were alive 1 year postoperatively, and the 5-year survival rate was 25.8%. Unusual findings in this series included two patients with metastatic basal cell carcinoma and one patient with a metastatic thyroid Hürthle cell carcinoma.  相似文献   
3.
目的 探索LDH实验检测细胞活力的可行性。方法 原代培养骨髓细胞和软骨细胞,用LDH实验测定上述两组细胞的活力,并与镜下活体观察到细胞的生长状况相比较。与目前比较成熟的测定细胞活力的MTS实验的测得的值相比较。结果 LDH实验对上述两组细胞的活力的测定结果与镜下活体观察到的结果相符合。与MTS实验的测得的结果经统计学处理无显著差异。结论 LDH实验可用于细胞活力的直接测定,而对活细胞的生存、繁殖无影响。  相似文献   
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John Milton (1608–1674) often has been regarded as the greatest poet of his time, yet he did not compose his most famous work,Paradise Lost, until after he had become blind in both eyes. On the basis of clues in Milton's writings, several possible diagnoses have been advanced to explain his loss of vision. The evidence for and against each theory is presented.  相似文献   
6.
The interrelationships between hemodynamic variables including right ventricular (RV) performance with filling/ejection dynamics of the Novacor left ventricular assist system (LVAS) were determined in 10 of 11 patients who received LVAS as a bridge to heart transplant. Nine were successfully transplanted. Data were obtained intraoperatively, at periodic intervals up to 48 h postimplant and at explant. The hypotheses investigated included (a) RV performance influences LVAS filling characteristics and (b) LVAS pump output is influenced by systemic vascular resistance (SVR). During the period of LVAS support (2-126 days), pumping characteristics included a mean filling volume of 51 ml (range, 24-70), residual volume of 4.9 ml (range, 1-18), pump rate of 113/min (range, 63-175), and pump output of 5.81/min (range, 2.8-8.2). Multiple regression analysis identified pulmonary vascular resistance (PVR), RV stroke work index (RVSWI), and pulmonary capillary wedge pressure, but not RV ejection fraction, pulmonary artery pressure, or central venous pressure (CVP) as the most important correlates with LVAS filling volume (p less than 0.001, R2 = 0.6). In addition, LVAS pump output was influenced mainly by RVSWI, PVR, and SVR (p less than 0.001, R2 = 0.7). It was concluded that LVAS performance is highly dependent on RV function and systemic/pulmonary vascular resistances.  相似文献   
7.
Parathyroid hormone secretion is negatively regulated by a 7- transmembrane domain, G-protein coupled Ca(2+)-sensing receptor. We hypothesized that activating mutations in this receptor might cause autosomal dominant hypoparathyroidism (ADHP). Consistent with this hypothesis, we identified, in two families with ADHP, heterozygous missense mutations in the Ca(2+)-sensing receptor gene that cosegregated with the disorder. None of 50 normal controls had either mutation. We also identified a de novo, missense Ca(2+)-sensing receptor mutation in a child with severe sporadic hypoparathyroidism. The amino acid substitution in one ADHP family affected the N-terminal, extracellular domain of the receptor. The other mutations involved the transmembrane region. Unlike patients with acquired hypoparathyroidism, patients with these mutations had hypercalciuria even at low serum calcium concentrations. Their greater hypercalciuria presumably reflected activation of Ca(2+)-sensing receptors in kidney cells, where the receptor negatively regulates calcium reabsorption. This augmented hypercalciuria increases the risk of renal complications and thus has implications for the choice of therapy.   相似文献   
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AIM: To determine the presence and nature of amyloid in prostatic corpora amylacea using immunohistological studies. METHODS: Prostatic tissue from 18 transurethral and two open resection specimens was studied. Paraffin wax embedded tissue sections were stained with haematoxylin and eosin and the alkaline Congo red method with and without previous treatment with potassium permanganate. Sections were also stained with antibodies to amyloid A, beta 2 microglobulin, lambda and kappa light chains, prealbumin IgA, G, M, S100 protein, prostatic specific antigen, amyloid P component and CAM 5.2 (control and blocking studies were performed). RESULTS: The prostatic corpora amylacea universally showed the presence of amyloid. In all instances this contained beta 2 microglobulin. CONCLUSION: Prostatic corpora amylacea represents a localised amyloidosis of beta 2 microglobulin origin that is unrelated to chronic renal failure and haemodialysis.  相似文献   
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