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The Centers for Disease Control and Prevention (CDC) and 35 partner organizations have engaged in developing an agenda for Preconception Health. A summit was held in June 2005 to discuss the current state of knowledge regarding preconception care and convene a select panel to develop recommendations and action steps for improving the health of women, children, and families through advances in clinical care, public health, and community action. A Select Panel on Preconception Care, convened by CDC, deliberated critical related issues and created refined definition of preconception care. The panel also developed a strategic plan with goals, recommendations, and action steps for improving preconception health. The recommendations and action steps are specific to the implementation of health behavior, access, consumer demand, research, and surveillance activities for monitoring and improving the health of women, children and families. The outcome of the deliberations is the CDC publication of detailed recommendations and action steps in the Morbidity and Mortality Weekly Report series, Recommendations and Reports.

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We have compared levels of albumin and serum amino acids in a group of 87 recent admissions to a nursing home, average age 83 years, with a group of healthy moderately old subjects, average age 69 years. We found that the nursing home group was characterized by decreased levels of albumin, by increased total levels of the measured amino acids, and by increased levels of the nonessential amino acids. In contrast, there were no significant group differences in the essential amino acids. Among the nursing home patients, there was a negative correlation between essential amino acids and disability, consistent with nutritional deficits in the more disabled patients, and a positive correlation between essential amino acids and subjective complaints of pain, suggesting that pain is associated with breakdown or mobilization of endogenous protein stores. Though the nursing home patients had decreased serum levels of tryptophan, there was no association between serum tryptophan or other variables that could be related to the availability of tryptophan for transport into brain, with ratings of either depression or pain. Glutamine levels were significantly increased in the nursing home residents, and among these patients they were positively correlated with measures of cognitive impairment.  相似文献   
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We studied nine patients with a subacute onset of a pancerebellar syndrome. Six had known cancer (three small-cell carcinoma of the lung [SCLC], one metastatic small-cell carcinoma, one small-cell carcinoma of the prostate, and one non-Hodgkin's lymphoma). Six of eight who had neurophysiologic testing, including the three patients without detectable cancer, had coexistent Lambert-Eaton myasthenic syndrome (LEMS). In two of the patients, LEMS was discovered only by neurophysiologic testing. We looked for anti-Purkinje cell autoantibodies in all patient's sera and in four patients' CSF. We also looked for autoantibodies to voltage-gated calcium channels (VGCCs) in seven patients' sera and two patients' CSF, using the 125I-omega-conotoxin radioimmunoassay. We were unable to detect anti-Purkinje cell autoantibodies in any patients' serum or CSF. However, there were raised titers of anti-VGCC autoantibodies in five of seven patients' serum, including one patient with SCLC who did not have LEMS, and in the CSF of one of two patients. We conclude that the frequency of presentation of a pancerebellar syndrome with LEMS is higher than expected by chance and is usually associated with cancer. In some of these patients, LEMS may be clinically occult. The presence of LEMS and raised titers of anti-VGCC autoantibodies in some patients with subacute cerebellar degeneration is suggestive of an autoimmune etiology even though anti-Purkinje cell antibodies could not be detected. Anti-VGCC autoantibodies are not confined to LEMS. They may be found at high titer in CSF as well as serum.  相似文献   
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To ascertain the range of neurological problems in patients with systemic cancer, we prospectively evaluated neurological symptoms, neurological diagnoses, and primary tumors in all patients with a history of systemic cancer examined by the Department of Neurology at the Memorial Sloan-Kettering Cancer Center, from Jul 1, 1990, to Dec 31, 1990. Of the 815 patients seen for neurological symptoms, less than half (45.2%) had metastatic involvement of the nervous system. The three most common symptoms were back pain (18.2%), altered mental status (17.1%), and headache (15.4%). The most common neurological diagnosis was brain metastasis (15.9%), followed by metabolic encephalopathy (10.2%), pain associated with bone metastases only (9.9%), and epidural extension or metastasis of tumor (8.4%). Of 133 patients with undiagnosed back or neck pain, 44 (33%) had epidural extension or metastases from tumor and 40 (30%) had pain associated with vertebral metastases only. In 15 (11%) the cause for the back pain was unrelated to metastatic disease. Of 132 patients seen on initial consultation for altered mental status, metabolic encephalopathy was the major neurological diagnosis (80; 61%); 20 (15%) had intracranial metastases. Of 97 patients with undiagnosed headache, 59 (61%) had a nonstructural cause. Fifty-three of these patients had either migraine, tension headache, or headache related to systemic illness (e.g., fever, sepsis). These results indicate that even in patients with systemic cancer, a group particularly prone to developing neurological disease that can be diagnosed radiologically, the role of clinicians remains important in helping distinguish noncancer-related and nonmetastatic neurological problems.  相似文献   
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Objective : To measure the geometric resistance to blood flow in human colorectal carcinoma. Although tumor blood flow is of central importance in both the detection and the treatment of cancer, the determinants of blood flow through the neoplastic circulation are poorly understood. Methods : Human colorectal carcinomas (tissue weight = 272 g ± 43 g (SD), n = 6) were perfused ex vivo with a buffered physiological salt solution of known viscosity at flow rates ranging from 2.5 to 40 ml/min and perfusion pressures from 8 to 100 mm Hg. The geometric resistance was determined from the slope of the pressure-flow curve. For examination of the principal determinant of geometric resistance, the vascular architecture, one of the tumors was perfused with Batson's No. 17 polymer and macerated in KOH to produce a positive vascular cast that was used for measurement of vascular branching patterns and dimensions. Results : The pressure-flow relationship was linear at perfusion pressures above 40 mm Hg, and the geometric resistance, z0, was constant at approximately 6.5 ± 109g/cm3. Below 40 mm Hg, z0 increased rapidly. The architecture of the arteriolar and capillary networks of human colorectal carcinoma is similar to those of experimental rodent tumors. Capillaries in planar and nonplanar mesh-works had mean segment diameters of 11 ± 2 and 9.6 ± 2 μm, lengths of 46 ± 24 and 107 ± 40 μm, and intercapillary distances of 46 ± 13 and 74 ± 24 μm, respectively. Conclusions : The geometric flow resistance in neoplastic tissue is 1–2 orders of magnitude higher than that observed in normal tissues. A decrease in functional vascular cross-sectional area may explain the additional increase in resistance at small perfusion pressures. The observed flow resistance may be due to the specialized arteriolar and capillary network architecture, pressures exerted by proliferating cancer cells, and/or coupling between vascular and extravascular flow. These observations demonstrate that tumor vascularity alone may not be indicative of flow resistance or tumor susceptibility to blood-borne therapeutic agents.  相似文献   
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The purpose of the present investigation was to determine if the salivary counts of 40 common oral bacteria in subjects with an oral squamous cell carcinoma (OSCC) lesion would differ from those found in cancer-free (OSCC-free) controls.  相似文献   
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