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81.
82.
Interhemispheric hyperdensity or unenhanced computed tomography was originally considered a sign of subarachnoid hemorrhage, the "falx sign." It has since been identified as a normal feature and has also been seen with interhemispheric subdural hemorrhage. To determine the differential features of interhemispheric hemorrhage, 50 patients with subarachnoid hemorrhage and 32 patients with interhemispheric subdural hematomas were reviewed. Subarachnoid hemorrhage produced anterior interhemispheric hyperdensity only, with a zigzag contour and extension from the calvarium to the rostrum of the corpus callosum. Interhemispheric subdural hematomas produce unilateral crescentic hyperdensities that are largest in the posterior superior part of the fissure, behind and above the splenium of the corpus callosum. Interhemispheric hyperdensity in children is more complex. Because the anterior part of the fissure is narrow in younger patients, subarachnoid hemorrhage may go undetected. Likewise, interhemispheric subdural hematomas in children are smaller and more difficult to recognize. They produce asymmetric thickening of the falx shadow with extension over the tentorium. They are, however, of great significance since they are generally seen in abused patients and carry a poor prognosis.  相似文献   
83.
A continuous cell culture line was established from a bone marrow metastasis of small cell anaplastic carcinoma of the lung. The cultures were characterized by light and electron microscopy, and an unusual concentric arrangement of cells was observed, both in sectioned material from the patient's tumor and from the cell cultures. The cells had two types of specialized cell junctions and contained secretory-like granules of the type described in neuroendocrine cells. Lactic dehydrogenase isozyme patterns were the same as those observed in normal human serum, and the karyotype revealed the presence of several marker chromosomes. Vasopressin was present in the cells and secreted into the culture medium in the absence of neurophysin, as shown by the immunoperoxidase technique and radioimmunoassay. Oxytocin was also absent from cells.  相似文献   
84.
Hypothalamic neurons secreting vasopressin and neurophysin.   总被引:2,自引:0,他引:2  
  相似文献   
85.
OBJECTIVE: The authors determined the frequency of anxiety disorders in a large group of depressed outpatients seeking treatment. METHOD: The Structured Clinical Interview for DSM-IV was administered to 373 depressed outpatients. RESULTS: More than one-half of the patients met the full criteria for a current anxiety disorder, and more than one-half of the patients with an anxiety disorder had more than one. When partial remissions and anxiety disorder diagnoses classified as "not otherwise specified" were included, two-thirds of the patients had a current anxiety disorder and three-quarters had a lifetime history of an anxiety disorder. CONCLUSIONS: The majority of patients with a principal diagnosis of unipolar major depressive disorder have a comorbid anxiety disorder. Because antidepressant medications have differential efficacies for anxiety disorders, knowledge of the presence of a comorbid anxiety disorder in a depressed patient may have treatment implications.  相似文献   
86.
The objectives of the present report were: a) to determine the spontaneous remission rate in depressed outpatients who do not receive antidepressant medication; b) to develop a novel method for obtaining a control group that can be used to gauge the effectiveness of antidepressant medication in clinical practice; and c) to compare response rates from the present sample with outcomes of depressed patients in our practice who were treated with antidepressant medications. By using a naturalistic design, prospective assessments were made on all depressed outpatients. Twenty-five patients who met full criteria for a major depressive episode ended up not taking antidepressant medication for a variety of reasons. "Response" rates to a no-treatment trial were determined with standard outcome criteria using the Clinical Global Impression-Improvement scale. Eight patients (32.0%) had a positive response, 5 patients (20.0%) had a partial response, and 12 patients (48.0%) were nonresponders to a no-treatment trial. These response rates were higher than expected, but significantly lower than what we had found in a cohort of depressed patients who underwent an antidepressant trial (p = .02). Likewise, treatment-resistant patients fared better on pharmacotherapy, though this difference was not statistically significant. These results suggest that the occurrence of spontaneous remissions may be common in clinical practice, and therefore the specific short-term benefits of antidepressant medication in clinical practice may frequently be overestimated. Despite the high rate of spontaneous remission in our sample, the present study allowed us to confirm the effectiveness of antidepressant medication in clinical practice using a novel method for obtaining a control comparison group.  相似文献   
87.
88.
The Mental Health Department of the Canadian Forces Support Unit (Ottawa) developed the Care for the Caregivers program to help participants deal with stressful events experienced directly or vicariously from the NATO and United Nations military missions of the 1990s. The program was developed after complaints of postdeployment stress were received from various military care providers. The objectives were to improve the skills of support personnel and to reduce the distress that some caregivers experienced. Thirty-one chaplains who had been exposed to stressful military operations participated in five workshops. These educational 4-day small-group workshops covered topics such as post-traumatic stress disorder, vicarious traumatization, coping techniques, spirituality, self-care, and family issues. An adult education model was chosen to encourage dialogue. Outcomes included reports of professional and personal benefits, requests for additional programs, local education initiatives, and referrals to mental health professionals. Having met its objectives, the program has become a normal concluding part of stressful deployments.  相似文献   
89.
PURPOSE: Up-regulation of both inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) enzymes has been reported in colorectal cancer. We aimed at evaluating the possible interaction between the nitric oxide and COX-2 pathways, and its effect on promoting tumor angiogenesis. EXPERIMENTAL DESIGN: Expression of iNOS, COX-2, vascular endothelial growth factor (VEGF), and CD31 was analyzed in tumor samples and corresponding normal mucosa obtained from 46 surgical specimens. We also evaluated iNOS activity, prostaglandin E(2) (PGE(2)), cyclic GMP and cyclic AMP production in the same specimens. Nitrite/nitrate levels, and PGE(2) and VEGF production were assessed in HCT116 and HT29 colon cancer cell lines after induction and selective inhibition of the two enzyme pathways. RESULTS: A significant correlation was found between iNOS and COX-2 immunohistochemical expression. PGE(2) production significantly correlated with iNOS activity and cGMP levels. A significant correlation was also found among PGE(2) production, microvessel density, and VEGF expression. Coinduction of both iNOS and COX-2 activities occurred after lipopolysaccharide (LPS) and epidermal growth factor (EGF) treatment in HCT116 and HT29 cells. Inhibition of iNOS by 1400W significantly reduced both LPS- and EGF-induced PGE(2) production. Treatment with LPS, EGF, and arachidonic acid significantly increased VEGF production in the iNOS-negative/COX-2-positive HT29 cells. This effect was completely reversed by treatment with the selective COX-2 inhibitor celecoxib. CONCLUSIONS: Our data showed a prominent role of nitric oxide in stimulating COX-2 activity in colorectal cancer. This interaction is likely to produce a cooperative effect in promoting angiogenesis through PGE(2)-mediated increase in VEGF production.  相似文献   
90.
Background: The presence in bone marrow of cells which react with monoclonal antibodies against tumor-associated antigens has been proposed over the last few years as a new prognostic factor in breast cancer patients. Patients and methods: Bone marrow aspirates were obtained from 109 stage I and II breast cancer patients during or 2–4 weeks after primary surgery. The samples were processed for leukocyte separation on a Ficoll-Hypaque gradient and then used to prepare cytospin slides for immunocytochemical analysis. The slides were stained with a pool of monoclonal antibodies (MoAbs) which recognize tumor associated antigens, using the alkaline phosphatase anti-alkaline phosphatase method. The median follow-up was 36 months (range 15–62); 22 patients relapsed and 7 died. Results: Thirty-four of the 109 patients (31.1%) had MoAb positive bone marrow cells. The bone marrow was positive in 28/74 (37.9%) patients who had the aspirate taken during surgery and in 6/35 (17.1%) who had it taken after surgery (p = 0.055). No association was found between bone marrow positivity and tumour size, nodal status, menopausal status, estrogen receptor positivity or the proliferative index. No association was found between bone marrow and prognosis: the log-rank test was 0.291 (p > 0.5) for OS and 0.023 for DFS; the hazard ratio (positive vs negative) was 1.51 for OS (95% CI: 0.33–6.86) and 0.93 for DFS (95% CI: 0.35–2.45). Conclusions: In our series, bone marrow positivity did not correlate with prognostic parameters or prognosis. Of interest is the relative excess of positivity when the bone marrow was obtained during surgery.  相似文献   
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