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91.
Gene expression in luteinizing hormone-releasing hormone (LHRH) neurons was analyzed during the periovulatory period to (1) characterize temporal patterns of LHRH gene expression and their relationship(s) to gonadotropin surges, and (2) determine if any such changes are uniform or dissimilar at different rostrocaudal levels of the basal forebrain. The number of neurons expressing mRNA for the decapeptide, and the relative degree of expression per cell were analyzed using in situ hybridization and quantitative image analysis. Rats were killed at 1800 hr on metestrus (Met), 0800 hr, 1200 hr, 1800 hr, and 2200 hr on proestrus (Pro), or 0200 hr, 0800 hr, and 1800 hr on estrus (E; n = 5-6 rats/group). All sections were processed for LHRH mRNA in a single in situ hybridization assay. Sections were atlas matched and divided into four rostrocaudal groups for analysis: vertical limb of the diagonal band of Broca (DBB), rostral preoptic area/organum vasculosum of the lamina terminalis (rPOA/OVLT), medial preoptic area (mPOA), and suprachiasmatic/anterior hypothalamic area (SCN/AHA). Plasma LH and FSH levels from all animals were analyzed by RIA. The labeling intensity per cell was similar among all time points at all four rostrocaudal levels. The number of cells expressing LHRH mRNA, however, varied as a function of time of death during the estrous cycle, and this temporal pattern varied among the four anatomical regions. At the level of the mPOA, the number of cells was highest at 1200 hr on Pro, and then declined and remained low throughout the morning of E. At the level of the rPOA/OVLT, the greatest number of LHRH neurons was noted later in Pro, at 1800 hr, dropping rapidly to lowest numbers at 2200 hr. No significant changes in LHRH cell number occurred at the DBB or SCN/AHA levels. At all anatomical levels, the secondary surge of FSH was unaccompanied by any change in the number of neurons expressing LHRH mRNA. These data demonstrate that (1) the number of detectable LHRH mRNA-expressing cells fluctuates during the periovulatory period and (2) peak numbers of LHRH-expressing cells are attained in the mPOA before the onset of the LH surge and before peak LHRH cell numbers are seen at more rostral levels. A model is proposed in which gene expression in this subpopulation of LHRH neurons may be activated by preovulatory estrogen secretion and acutely reduced following the proestrous surge of progesterone.  相似文献   
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Visual agnosia is a neuropsychological syndrome characterized by a failure of object identification. Apperceptive agnosia, an object identification deficit caused by damage to early perceptual processes, has been explained by appealing to both damaged early sensory processes and to damaged preattentive grouping processes. Which of these two explanations best accounts for the behavior of these patients? We present results from two experiments designed to distinguish rival theoretical accounts of apperceptive agnosia. In our studies, we attempted to simulate apperceptive agnosia in neurologically intact subjects. Sensory-deficit accounts of the syndrome predict that degrading visual processing would make normal subjects perform like patients; grouping-deficit accounts predict that removing perceptual organization cues from visual displays would make normal subjects perform like patients. We were able to simulate the behavior of an apperceptive agnosic patient by removing perceptual organization cues, consistent with a grouping-deficit account of this syndrome. The implications for understanding both apperceptive agnosia and normal visual functioning are discussed.  相似文献   
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Using a TCR transgenic mouse bred onto a recombinase-activating gene-2-deficient background, we have examined the influence of B7.1 and B7.2 on activation of naive, CD8+ T cells in vitro. We found that B7.1 was a more potent costimulus than B7.2 for induction of proliferation and IL-2 production by naive CD8+ T cells. This difference appeared to be quantitative in nature, as determined using transfectants expressing various defined levels of B7.1 or B7.2, or using purified B7.1 or B7.2 fusion proteins. In contrast to the quantitative differences seen in stimulation of naive T cells, B7.1 and B7.2 were comparable in their ability to costimulate responses in T cells previously primed in vitro. In addition, primed, but not naive, T cells were capable of proliferating and producing IL-2 in response to a TCR stimulus alone, apparently in the absence of B7 costimulation. Lastly, we found that B7.1 and B7.2 were equivalently capable of driving differentiation of naive CD8+ T cells into an IL-4-producing phenotype when exogenous IL-4 was added to the primary culture or to an IFN-gamma-producing phenotype in the presence of IL-12. These results indicate that signals generated by B7.1 and B7.2 are qualitatively similar, but that B7.1 is quantitatively stronger than B7.2. Further, our results indicate that the activation state of the responding T cell may influence the efficiency with which the T cell can respond to a costimulatory signal provided by either B7.1 or B7.2.  相似文献   
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OBJECTIVE: This study examines our continuing experience in performing vaginal hysterectomies and laparoscopy-assisted vaginal hysterectomies with an outpatient protocol. The purpose was to review factors associated with discharge and hospitalization. STUDY DESIGN: Surgical records from all women entering our previously reported outpatient hysterectomy protocol were reviewed. Demographics, surgical indications, intraoperative data, and postoperative data were studied, and their associations with patient discharge and hospitalization were determined. Specific attention was directed to complications. RESULTS: The study group consisted of 133 women. Twelve women (9.0%) were not discharged from the hospital and 5 (3.8%) required readmission. Surgical indications, the type of hysterectomy, and the requirement for pain medication revealed no association with hospitalization. The occurrence of an intraoperative complication (p < 0.000), the need for transfusion (p = 0.043), and postoperative antiemetics (p = 0.013) were statistically associated with hospitalization. In addition, low hematocrit values and elevated temperatures on the first and second postoperative days were associated with hospitalization. CONCLUSION: Long-term experience with outpatient hysterectomy reveals a hospitalization rate of 12.8%. Complications, blood loss, elevated temperatures, and postoperative nausea are the major determinants of patient discharge and hospitalization. Readmission rates continue to remain low.  相似文献   
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An independent examiner evaluated 179 consecutive private ambulatory litigant patients with soft tissue neck injuries (whiplash) from automobile injuries. Treatment of all patients consisted of neck and shoulder exercises with the exclusion of cervical collars, cervical traction and hospitalization. Forty-three patients had intermittent cervical traction in addition to the exercises. All patients were encouraged to resume their usual work and other activities. The presence of interscapular or upper back pain prognosticated a less favorable result. The average length of treatment was 7.4 weeks. Thirty-seven per cent of the patients with asymptomatic; 16 per cent showed no significant recovery. Older patients recovered as well as younger patients. There was no relation between X-ray findings of flattening or reversal of the cervical lordotic curve and the degree of recovery.  相似文献   
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Total joint replacement procedures should be restricted to older individuals or persons with limited physical activities or life expectancy. However, on occasion a total joint replacement may be the only means to avoid serious disability in a young, otherwise healthy individual. This report of a 19-year-old woman who underwent a total hip joint replacement following unsuccessful treatment of a severely comminuted intracapsular hip fracture. Subsequent to the total hip joint replacement the patient experienced a normal pregnancy and delivery.  相似文献   
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