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81.
The effect of GRH infusion on rat adenohypophysial morphology was studied by light microscopy, immunocytochemistry, in situ hybridization, and electron microscopy. Synthetic rat GRH was intravenously administered by osmotic minipumps at 14.4, 72, 360 and 720 μg/ day/rat for 1 week. In one group treated for 1 week with a daily dose of 720 μg GRH, the rats were killed 7 days after withdrawal of GRH. Control rats in which GRH was replaced by excipient, or those that received no treatment, were included as well. GRH infusion with daily doses of 360 and 720 μg resulted in a significant increase in pituitary weight and weaker GH immunoreactivity compared with other groups. Ultrastructurally, the somatotrophs were increased in size and became sparsely granulated, and the organelles involved in hormone sythesis were very prominent. The intensity of the GH mRNA signal did not differ from control animals, suggesting the desensitization of somatotrophs to GRH. The highest GRH dose induced an increased number of nuclei immunoreactive for proliferation cell nuclear antigen (PCNA). One week after GRH withdrawal, shrinkage of cytoplasm, involution of RER and Golgi complex, and a decrease of cell attachment sites indicated the reversibility of changes induced by GRH. In conclusion, GRH infusion induced, within days, hypertrophy and proliferation of somatotrophs with ultrastructural features of highly stimulated, sparsely granulated cells. Morphological changes were reversible.Endocr Pathol 4:131–139, 1993.  相似文献   
82.
Summary We have recorded postural performance in 50 HIV-infected patients in different stages of the disease (Walter Reed (WR) stages I–VI) by means of a force measuring platform. The results were compared with 50 age-matched controls. A significant instability was particularly evident when standing on an unstable foot support. In patients standing with eyes closed, postural sway was significantly higher in every patient group (WR I–II:P<0.02, WR III–V:P<0.001, WR VI:P<0.001). Patients in stage WR I–II showed no relevant neurological abnormalities. In agreement with other neurophysiological data in the literature we suggest that postural imbalance could be an early sign of central nervous system penetration of HIV. No correlation with electromyographic or cerebrospinal fluid findings could be found.  相似文献   
83.
PURPOSE: To determine the safety, immunogenicity, and clinical response to an allogeneic tumor vaccine for non-small-cell lung cancer, we conducted a phase I trial in patients with advanced metastatic disease. PATIENTS AND METHODS: We treated 19 patients with a vaccine based on an adenocarcinoma line (AD100) transfected with B7.1 (CD80) and HLA A1 or A2. Patients were vaccinated intradermally with 5 x 10(7) cells once every 2 weeks. Three vaccinations represented one course of treatment. If patients had complete response, partial response, or stable disease, they continued with the vaccinations for up to three courses (nine vaccinations). Immune response was assessed by a change between pre-study and postvaccination enzyme-linked immunospot frequency of purified CD8 T-cells secreting interferon-gamma in response to in vitro challenge with AD100. RESULTS: Four patients experienced serious adverse events that were unrelated to vaccine. Another four patients experienced only minimal skin erythema. All but one patient had a measurable CD8 response after three immunizations. The immune response of six surviving, clinically responding patients shows that CD8 titers continue to be elevated up to 150 weeks, even after cessation of vaccination. Overall, one patient had a partial response, and five had stable disease. Median survival for all patients is 18 months (90% CI, 7 to 23 months), with corresponding estimates of 1-year, 2-year, and 3-year survival of 52%, 30%, and 30%, respectively. HLA matching of vaccine, age, sex, race, and pathology did not bear a significant relation to response. CONCLUSION: Minimal toxicity and good survival in this small population suggest clinical benefit from vaccination.  相似文献   
84.
We present the first use of tubeless superimposed combined high- and low-frequency jet ventilation (SHFJV) with a jet laryngoscope in laryngotracheal surgery in infants and children. Twenty-eight patients underwent 53 operative procedures. The average age of the patients was 7.3 years. The most common diagnoses were laryngeal papillomatosis and subglottic stenosis. The duration of jet ventilation averaged 33 min. The gas exchange was sufficient in each case. The advantages of SHFJV in the surgery of the laryngotracheal area in infants and children are optimal view at the larynx and trachea, maximum space for the handling, application of the laser without risks, no time limitation, suitability for stenosis, and neither anesthetic nor surgical complications.  相似文献   
85.
The incidence and characteristics of foramen thyroideum (FT) in embryonic and/or fetal larynges have not been established. In the present study, 90 adult larynges and 53 embryonic-fetal larynges were studied. The incidence of FT during the embryonic-fetal period (57%) was statistically different from the adult period (31%) (P = 0.005). All the FT found in the adult period contained vessels and/or nerves, while in the embryonic and fetal period only 63% presented neurovascular elements (P < 0.001). The origin of FT in the embryonic period and its persistence during adult life is discussed.  相似文献   
86.
Tamoxifen, which is used for treating breast cancer, exhibits estrogenic and antiestrogenic characteristics, depending on the tissue. In the human breast it acts as an antiestrogen, whereas estrogenic effects have been reported on endometrium and bone. The purpose of this study was to determine whether tamoxifen (TAM) prevents bone loss in elderly, postmenopausal women. Bone mineral density of the lumbar spine (SBD) was measured in elderly women (at least 10 years after menopause) 5 years after stage I or II breast cancer (n=111). The results showed that SBD in untreated patients (n=74) was significantly lower (p0.05) than SBD in patients (n=37) treated with TAM over 5 years. In a subgroup of patients (n=24) with positive estrogen receptor status, changes in SBD 12 months after discontinuation of 5-year TAM therapy were measured and compared with the changes of extended TAM treatment over a sixth year. Twelve months after withdrawal of 5-year TAM medication (n  相似文献   
87.
The purpose of this article is to examine the prevalence, degree, and natural course of pupillary neuropathy (PANP), cardiovascular autonomic neuropathy (CANP), and sensorimotor neuropathy (SNP) and to study the impact of disease stage and medication on neuropathy in 61 consecutive patients with HIV. PANP, CANP, and SNP were assessed by standardized test procedures. Overall prevalence of PANP, CANP, and SNP were 66%, 15%, and 15%, respectively. The maximal pupillary area (pupillary measure, p<0.0001) and the lying-to-standing ratio (cardiovascular measure, p<0.0001) were abnormal as compared with control subjects. The changes in CD4+ T-lymphocytes and respiratory sinus arrhythmia percentile during 2 years of follow-up correlated significantly (r=0.758, p=0.007). Patients with CANP were more often in an advanced disease stage than patients without CANP (p=0.004). SNP, but not PANP or CANP, was associated with the intake of the neuropathogenic drugs dideoxycytidine, dideoxyinosine, and 2,3 didehydro-2,3 dideoxythymidine (p<0.05). Autonomic and sensorimotor neuropathy are frequent in patients with HIV, and progression of CANP may put patients at risk for unexpected cardiorespiratory arrest.  相似文献   
88.
BACKGROUND: Fatal venous thromboembolism (VTE) is a rare complication of combined oral contraceptive (COC) treatment. This study aims to determine incidences of fatal VTE in relation to the type of COC and the percentage of cases reported to the Swedish Adverse Drug Reactions Advisory Committee (SADRAC). A further aim is to compare the characteristics of reported and not reported cases. METHODS: This retrospective study is a separate analysis using data from a larger study that included women aged 15-44 years between 1990 and 1999 with VTE coded as the underlying or contributory cause of death in the Swedish Cause of Death Register. COC use within 2 months of the date of symptom onset or death was identified in 28 cases. Sales data were obtained from the National Corporation of Swedish Pharmacies. Reported cases were identified in the SADRAC database. RESULTS: After excluding two cases where the type of COC was unknown, the crude incidences of fatal VTE were 5.1 (95% CI 2.3, 9.6), 8.6 (95% CI 4.3, 15.4) and 9.1 (95% CI 3.3, 19.8) cases per million women per year for levonorgestrel-, desogestrel- and norethisterone-containing COCs, respectively. Age-adjusted incidences were approximately twice as high for desogestrel- and norethisterone-containing COCs compared with levonorgestrel-containing COCs, although differences were not statistically significant. Thirty-six percent of cases were reported. Reporting was positively associated with information in medical records relevant to the VTE diagnosis that the patient was a COC user and was significantly higher in northern Sweden. CONCLUSION: Results from this study support a higher incidence of fatal VTE with desogestrel-containing COCs than with levonorgestrel-containing COCs.  相似文献   
89.
BACKGROUND: The proportion of Australian adults achieving physical activity levels believed to be sufficient for colon cancer prevention was estimated, and sociodemographic correlates (age, gender, educational attainment, occupation, marital status, and children in household) of meeting these levels of activity were analyzed. METHODS: Data from the 2000 National Physical Activity Survey were used to estimate the prevalence of participation in physical activity in relation to three criteria: generic public health recommendations, weekly amount of at least moderate-intensity physical activity currently believed to reduce risk of colon cancer, and weekly amount of vigorous-intensity physical activity believed to reduce risk of colon cancer. RESULTS: Overall, 46% of adults met the generic public health criterion, 26% met the colon cancer criterion based on participation in at least moderate-intensity physical activity, and 10% met the colon cancer criterion based on vigorous-intensity physical activity. Women were less likely than men to meet the colon cancer criteria. Younger and more educated persons were more likely to meet all three criteria. The most pronounced differences between gender, age, and educational attainment groups were found for meeting the amount of vigorous-intensity physical activity believed to reduce risk of colon cancer. CONCLUSIONS: The population prevalence for meeting proposed physical activity criteria for colon cancer prevention is low and much lower than that related to the more generic public health recommendations. If further epidemiologic studies confirm that high volumes and intensities of activity are required, the public health challenges for colon cancer will be significant.  相似文献   
90.
PURPOSE: Both the retinoblastoma and p53 pathways are often genetically altered in human cancers and their complex regulation is in part mediated by the three gene products p16, p14(ARF), and p15 of the INK4 locus on chromosome 9p21. Partial or complete biallelic deletions of the INK4 locus have been recognized in a variety of malignant tumors, including malignant melanoma. We have in the present study measured the frequency of INK4 deletions in a large number of melanoma metastases and determined their association with clinicopathologic variables and survival data. EXPERIMENTAL DESIGN: Quantitative real-time PCR, as well as fluorescence-based fragment analysis, has been used to perform measurements of the relative allelic concentrations of the INK4 genes in 112 human melanoma tumor samples from 86 patients. RESULTS: Thirty-eight of 86 melanoma patients (44%) had metastases with biallelic losses in INK4. Ten of 20 patients with multiple metastases showed similar deletion patterns in all analyzed tumors. There was no significant association between any of the clinicopathologic variables and loss of INK4. However, loss of INK4 had an adverse effect on median survival from time of diagnosis. Patients with tumors with diploid INK4 had a median survival of 142 months, whereas those with monoallelic or biallelic loss in INK4 had a median survival of only 47 months (P = 0.006). CONCLUSIONS: Our results point to homozygous deletions in the INK4 region as being one of the most common genetic alterations in malignant cutaneous melanoma. INK4 deletions are associated with an adverse prognosis.  相似文献   
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