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21.
PURPOSETo document differences in the cerebral proton MR spectra of patients with early and late stages of human immunodeficiency virus (HIV) infection.METHODWe studied the relative N-acetyl-aspartate (NAA) levels by localized proton spectroscopy of the parietooccipital region of the brain in 43 HIV-seropositive patients, including 26 with an acquired immunodeficiency syndrome (AIDS)-defining diagnosis, and in eight control subjects.RESULTSReduced relative NAA levels were shown in those HIV-1-seropositive patients: 1) with AIDS against HIV-1-seropositive patients without AIDS (P < .04); 2) with HIV-1-associated cognitive/motor complex against neurologically healthy patients (P < .007); 3) with encephalopathic changes on MR against those with normal imaging (P < .001); and 4) on follow-up against their results on initial study (P < .03).CONCLUSIONSBy clinical (Centers for Disease Control classification) and radiologic (MR evidence of white-matter disease) criteria indicating late-stage HIV infection, reduced relative levels of NAA have been demonstrated. Spectroscopic abnormalities can be quantitatively tracked with time. This paper demonstrates the clinical use of detecting NAA as a putative in vivo measure of the neuronal loss that has been demonstrated in postmortem studies of patients with AIDS. This neuronal loss, which is believed to underlie the HIV-1-associated cognitive/motor complex, is thought to be attributable directly or indirectly to the presence of HIV in the brain. Proton spectroscopy may serve as a quantitative noninvasive indicator of this aspect of cerebral involvement in HIV disease.  相似文献   
22.
Summary We enrolled children with acute lymphoblastic leukemia (ALL) in a Pediatric Oncology Group (POG) pilot study to monitor erythrocyte (RBC) methotrexate (MTX) and folate (F) levels before and during treatment. The mean value for RBCF at diagnosis was 0.86±0.46 nmol/ml RBC in the 214 patients who achieved remission and 1.21±0.74 nmol/ml RBC in the 10 patients who did not (P=0.020). Folate levels tended to increase during remission induction, but they dropped following an intensive consolidation with methotrexate to levels that were sustained throughout chemotherapy treatment. Methotrexate levels reached mean values of approximately 0.15 nmol/ml RBC at the end of an intensive methotrexate consolidation, then fell to levels that were sustained throughout maintenance therapy. There was a weak correlation between improved event-free survival and higher RBCMTX levels after consolidation, but no correlation was found between improved survival and the level of RBCMTX or RBCF during maintenance therapy. A larger study with more complete data is needed to determine whether RBCMTX or RBCF might be useful in predicting event-free survival in patients with ALL.This work was supported in part by grants from the National Cancer Institute and the National Institute of Health (CA-30969, CA-28476, CA29139, CA-159-89, and CA-33587)  相似文献   
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24.
OBJECTIVE: The authors tested the hypothesis that neuroleptic-induced extrapyramidal syndromes are associated with painful sensations objectively conforming to the characteristics of primary sensory symptoms as reported in idiopathic and postencephalitic parkinsonism. METHOD: The frequency of subjective painful sensory symptoms and their relation to neuroleptic-induced extrapyramidal syndromes were examined in a consecutive series of 107 psychiatric patients newly admitted to acute care units at a teaching hospital. Patients without illnesses or conditions likely to be associated with pain were included in the study if they had a diagnosis other than organic mental syndromes and were receiving psychotropic medications as prescribed by their treating physicians. Structured interviews with a modified version of the McGill Pain Questionnaire to assess sensory complaints and neurological examinations for neuroleptic-induced extrapyramidal syndromes (parkinsonism and akathisia) were conducted independently by two raters blind to each other's findings and patients' medication status. RESULTS: Fourteen (23%) of 60 patients receiving neuroleptics reported experiences of spontaneous pain subjectively attributed to pharmacological treatment, compared with only one (2%) of 47 patients receiving psychotropic medications other than neuroleptics. There was no difference between these two groups in subjective complaints of paresthesia (8% versus 9%). Twelve (55%) of the 22 patients with neuroleptic-induced extrapyramidal syndromes reported pain, compared with only two (5%) of the 38 patients who received neuroleptics but did not experience extrapyramidal syndromes. CONCLUSIONS: Although consonant with the study hypothesis, these results should be regarded as preliminary and interpreted conservatively in the light of the methodological limitations of the study.  相似文献   
25.
To define the indications for elective neck treatment, the cases of 474 previously untreated patients were reviewed who had locally confined major salivary gland cancers treated between 1939 and 1982. Clinically positive nodes were present in 14% (67 of 474). Overall, clinically occult, pathologically positive nodes occurred in 12% (47 of 407). By univariate analysis, several factors appeared to predict the risk of occult metastases; however, multivariate analysis revealed that only size and grade were significant risk factors. Tumors 4 cm or more in size had a 20% (32 of 164) risk of occult metastases compared with a 4% (nine of 220) risk for smaller tumors (P less than 0.00001). High-grade tumors (regardless of histologic type) had a 49% (29 of 59) risk of occult metastases compared with a 7% (15 of 221) risk for intermediate-grade or low-grade tumors (P less than 0.00001). In view of the low frequency of occult metastases in the entire group, routine elective treatment of the neck is not recommended. High-grade tumors and larger tumors have a high rate of occult neck metastases, and treatment should be considered in this group.  相似文献   
26.
ABSTRACT: Background: Increasingly, women seek involvement in decisions about their health care. The purpose of this study was to examine women's experience of, and satisfaction with, their involvement in health care decisions during a high‐risk pregnancy. Methods: Forty‐seven women with hypertension or threatened preterm delivery (including multiple births) were interviewed after the birth of their child. They received prenatal care at home from nurses in a community program or were hospitalized. The in‐depth interviews were audiotaped and transcribed; data were analyzed using constant comparative methods. Results: Women identified an increased feeling of responsibility for the health of their baby and themselves, but differed in choosing active or passive involvement in health care decisions. Women who wanted active involvement achieved it through one of three processes: struggling for, negotiating, or being encouraged. Women who wanted passive involvement and women facing health crises used the process of trusting in the expertise of nurses and physicians. Women were satisfied if the care from health care professionals was congruent with how they wanted to be involved in decision‐making. Conclusions: Although most women want to be actively involved in health decision‐making during a high‐risk pregnancy, some prefer a passive role. The setting of prenatal care, community‐based or in‐hospital, was less important than the ability of nurses and physicians to support the woman in her preferred role in decision‐making. (BIRTH 30:2 June 2003)  相似文献   
27.
Horner syndrome     
Horner syndrome is an uncommon but important clinical entity, representing interruption of the sympathetic pathway to the eye and face. Horner syndrome is almost always diagnosed clinically, though pharmacological testing can be used to confirm the diagnosis. Imaging modalities such as PET, CT and MRI are important components of work‐up for patients presenting with acquired Horner syndrome. Our patient’s presentation with Horner syndrome unmasked the causative superior sulcus squamous cell carcinoma and a coincidental lower lobe adenocarcinoma. Successful radical treatment of these cancers resulted in complete resolution of the syndrome and disease‐free survival at 18 months. We review the anatomy and pathophysiology underlying this and other causes of Horner syndrome.  相似文献   
28.
A cell line from Wilms' tumour with deletion in short arm of chromosome II   总被引:1,自引:0,他引:1  
A cell line (T3/73) from a Wilms' tumour has been established from a 9 month-old boy with aniridia. The tumour was removed in 1973. On histological examination a diagnosis of Wilms' tumour was made which showed undifferentiated areas, marked tubule formation and abundant striped muscle fibres. The tumour cells, which are fusiform, grew rapidly in culture without the addition of growth factors, and have undergone over 100 passages. Approximately 95% and 5% were positive for desmin and cytokeratin, respectively. The cell doubling time was 28 hr. Cytogenetic studies revealed a karyotype of 46,XY,del(11) (p12::p14). Although the cells stained very intensely with a monoclonal antibody that detects oncogene ras p 21 antigen, Southern blot analysis using c-Ha-ras as a probe failed to reveal an obvious deletion or amplification of either Ha-ras allele.  相似文献   
29.
Sixty-seven patients with keratoconus were classified according to atopic status. Keratoconus patients with and without atopy did not differ significantly with regard to sex, age of onset, or rate of keratoplasty, but patients with very high IgE levels were more prone to graft rejection. Atopy was less common in patients with unilateral keratoconus, and keratoconus occurred more frequently on the side of the dominant hand. There was a significantly lower frequency of HLA B7 in the keratoconus group than in the controls. No abnormalities of essential fatty acid metabolism were found in keratoconus patients with or without atopy. There was no social class bias in the group. The study included a brother and sister with keratoconus and atopy, and a non-atopic patient whose identical twin did not have keratoconus.  相似文献   
30.
In 1986, an outbreak of Moraxella follicular conjunctivitis occurred in girls attending a Navajo boarding school in New Mexico. We diagnosed 19 cases of culture-proven, and 21 of clinical conjunctivitis based on isolation of Moraxella from conjunctival cultures and the occurrence of symptoms significantly associated with positive culture. Sharing eye makeup was significantly associated with Moraxella-positive conjunctivitis (odds ratio [OR] = 7.2, P = .004) and showed a trend toward significance in those with clinical conjunctivitis (OR = 2.9, P = .09). Eyeliner and eye shadow were implicated (OR = 4.1, P less than .05). We cultured samples of 13 students' makeup; one third of the eyeliners were positive for Moraxella. Nasal carriage of Moraxella was found in 35 (44%) of the 79 female boarders and in 20 (21%) of 97 Navajo patients at two nearby clinics. In a prospective evaluation of the effect of patient education and rifampin therapy on the occurrence of conjunctivitis during an 11-month follow-up period, both types of intervention were successful in significantly reducing the rate of conjunctivitis when compared with that in a control group.  相似文献   
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