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61.
Lymphocyte transformation responses to phytohaemagglutinin and pokeweed mitogen in patients at differing stages of HIV infection: are they worth measuring? 下载免费PDF全文
A S Bansal A Moran M Potter R Taylor M R Haeney B K Mandal 《Journal of clinical pathology》1993,46(9):846-848
AIMS--To determine whether the routine measurement of lymphocyte transformation responses to mitogenic stimuli provide any information additional to that available from routine T cell CD4 and CD8 analysis in patients with HIV infection. METHODS--The case records of 197 immunologically investigated HIV seropositive patients were reviewed. The influence of disease stage on T lymphocyte subsets and lymphocyte transformation responses (LyTR) to phytohaemagglutinin (PHA) and Pokeweed mitogen was assessed. RESULTS--The median CD3 and CD4 counts and LyTR to PHA and Pokeweed mitogen were highest in patients with persistent generalised lymphadenopathy (PGL) and decreased progressively in the order: asymptomatic patients, those with ARC, those with AIDS. LyTR to PHA was preserved in over 70% of all patients, but the response to Pokeweed mitogen was depressed in 8% of patients with PGL, 34% of asymptomatic patients, 68% of those with ARC and 78% of those with AIDS. Subnormal values of both CD4 + T cells and LyTR to Pokeweed mitogen were more common in patients with ARC and AIDS (68%) than in those who were asymptomatic or had PGL (20%). CONCLUSIONS--CD4 T cell analysis and LyTR to Pokeweed mitogen, but not to PHA, both correlate with disease states in patients with HIV infection. 相似文献
62.
In the first 3 papers of this series (Furshpan et al., 1986a, b; Potter et al., 1986), a sensitive microculture procedure was used to show that sympathetic principal neurons, dissociated from newborn or adult superior cervical ganglia and grown singly on cardiac myocytes, display adrenergic, cholinergic, and purinergic functions, sometimes in isolation but more often in combination. In this paper we describe additional effects on cardiac myocytes evoked by these neurons; the effects were excitatory and insensitive to adrenergic blocking agents (and to agents that block the inhibitory effects of acetylcholine and purines). In some of these microcultures, evidence consistent with secretion of serotonin was obtained; the nonadrenergic excitatory effect was diminished or abolished by serotonin blockers or reserpine. Further evidence for serotonergic transmission is presented in the accompanying paper by Sah and Matsumoto (1987). In other cases, an as-yet-unidentified agent "X" also produced a nonadrenergic excitation. The X effect characteristically required a prolonged train of neuronal impulses, had a time course of 50-200 sec, and was insensitive to agents that affected the other transmitters, including serotonin. In addition, we discuss 2 remarkable features of the transmitter repertoire of the microcultured sympathetic neurons: expression of the several transmitters in a variety of combinations, including at-least-quadruple function, and expression of the transmitters within a particular combination in varying relative strengths. The result is a diversity of transmitter release greater than that previously reported for vertebrate or invertebrate neurons. 相似文献
63.
64.
Depressed patients demonstrate dysregulation in multiple neurochemical and neuroendocrine systems. The observed abnormalities are often subtle, involving "inefficiencies" in stress-responsive systems. Norepinephrine, acetylcholine, the hypothalamic-pituitary-adrenal axis, and the hypothalamic-pituitary-thyroid axis are among the major biochemical and hormonal sites of dysregulation in depression. 相似文献
65.
66.
Edward A. Sykes Madeline Lemke Daniel Potter Terry Li Zuhaib M. Mir Guy Sheahan Vincent Wu Boris Zevin 《Canadian journal of surgery》2021,64(1):E59
BackgroundSquare knots can be difficult to construct in deep body cavities. The reversing half-hitch alternating post (RHAP) surgical knot has noninferior tensile strength and performance characteristics in deep body cavities. We compared the enterotomy repairs of novice learners in simulated deep body cavities using RHAP versus square knots after proficiency-based training.MethodsUndergraduate students were randomized to RHAP (n = 10) or square knot (n = 10) groups and trained to defined proficiency. They then performed hand-sewn enterotomy repairs of cadaveric porcine small bowels on flat surfaces and in simulated deep body cavities. We recorded time to knot-tying proficiency and to enterotomy repair, and burst pressures for the repair.ResultsMean time-to-proficiency in knot tying was equivalent between the RHAP and square knot groups (23 [standard deviation (SD) 3] v. 21 [SD 2] min, p = 0.33). Mean time for enterotomy repair in deep cavities was shorter for the RHAP group (16 [SD 2] min v. 21 [SD 1] min, p = 0.02). Mean burst pressures for enterotomy repair were equivalent on flat surfaces (128 [SD 41] v. 101 [SD 36] mm Hg, p = 0.31), and were significantly higher for the RHAP group in simulated deep body cavities (32 [SD 13] v. 105 [SD 37] mm Hg, p = 0.05).ConclusionThe RHAP knots appear to have superior performance versus square knots when tied in a deep body cavity by novice learners. Future work should focus on demonstrating the clinical relevance and broad utility of the RHAP knot in abdominal surgery. Both knot types should be taught to novice learners. 相似文献
67.
Christian R. De Potter Anne-Marie Schelfhout 《Virchows Archiv : an international journal of pathology》1995,426(2):107-115
The neu-protein is overexpressed in about 20% of invasive duct cell carcinomas of the breast. The only reliable sign for neu-overexpression by immunohistochemistry is membrane staining. Its overexpression is correlated with decreased overall survival and disease free survival due to increased metastatic activity of neu-overexpressing tumour cells. This increased metastatic potential is a consequence of the motility enhancing activity of the neu-protein, which is exclusively expressed on pseudopodia, and to a lesser extent of its growth stimulating effect. From a clinical point of view, the assessment of neu-overexpression in breast cancer might become a useful tool in the future treatment of patients by chemotherapy, since patients whose tumour shows neu-overexpression benefit from higher doses of chemotherapy. The molecule plays a key role in the pathogenesis of Paget's disease of the breast. A chemotactic factor which is secreted by epidermal keratinocytes attracts the Paget cells to spread into the epidermis and acts via the neu-protein. In ductal carcinoma in situ, the combination of neu-overexpression and large cell type is highly correlated with extent of disease and therefore neu-overexpression might be a predictive marker for recurrence of disease after tumour resection. 相似文献
68.
Induction of inflammatory cell infiltration and necrosis in normal mouse skin by the combined treatment of tumor necrosis factor and lithium chloride. 下载免费PDF全文
R. Beyaert C. De Potter B. Vanhaesebroeck F. Van Roy W. Fiers 《The American journal of pathology》1991,138(3):727-739
Previously we reported that lithium chloride (LiCl) potentiates tumor necrosis factor (TNF)-mediated cytotoxicity in vitro and in vivo. Here, using a murine normal skin model, it is shown that a subcutaneous injection of TNF plus LiCl induces acute dermal and subcutaneous inflammation and necrosis. Histology showed a marked initial dermal and subcutaneous neutrophil infiltrate by approximately 2 hours, followed by a predominantly mononuclear infiltrate by 24 hours, which remained present for several days. Tumor necrosis factor or LiCl alone induced negligible inflammation, disappearing after 6 hours; furthermore there was never necrosis or ulceration of the overlying skin in case of single-agent application. In vitro studies showed that the combination of TNF and LiCl, but not either agent alone, was directly cytotoxic to fibroblastic cells of murine skin. No inflammatory infiltration was visible in tumors treated intratumorally or perilesionally with TNF plus LiCl, although the latter treatment resulted in a perilesional leukocyte infiltration. Furthermore the combination of TNF and LiCl had no effect on macrophage cytotoxicity to L929 tumors. 相似文献
69.
Ricour C Gorski AM Goulet O de Potter S Corriol O Postaire M Nihoul-Fekete C Jan D Revillon Y Lortat-Jacob S Pellerin D 《Clinical nutrition (Edinburgh, Scotland)》1990,9(2):65-71
It is essential that children on prolonged parenteral nutrition for anatomical or functional loss of small bowel should enjoy a quality of life which is as normal as possible. Their return home is a major factor in this. Over the past 8 years, 112 children were able to remain at home on cyclic parenteral nutrition. Forty-nine of them are no longer on home parenteral nutrition (HPN), 45 are still on HPN, and 18 have died. Growth and quality of life were good in most cases. Most of the complications were from infection, 1 septicaemia per 594 days on HPN. In the light of these results, HPN seems to be the best option for children requiring prolonged parenteral nutrition, although it can only be considered within the framework of a specialized centre, which ensures patient follow-up, and provides the logistical support required for this high-technology treatment. 相似文献
70.
There have been many recent advances in the diagnosis and management of children with retinoblastoma. Regarding diagnosis, the judicial use of ancillary studies, particularly B-scan ultrasonography, has been instrumental in supplementing the diagnosis when opaque media preclude a clear view of the underlying neoplasm. Computed tomography and magnetic resonance imaging are important in the early detection of associated pinealoblastoma, which occurs as part of the recently described syndrome of "trilateral retinoblastoma." With regard to management, the technique of enucleation continues to improve and the scleralized hydroxyapatite implant is now available to provide a better cosmetic appearance and better motility of the artificial eye. Methods have been described for harvesting fresh tumor tissue immediately after enucleation for special DNA studies. Recent reports have documented a decreasing frequency of enucleation and an increasing tendency to use eye-preserving methods of management. Plaque radiotherapy, which provides more localized irradiation to the specific tumor, is gradually supplanting external beam irradiation for localized retinoblastoma that does not exhibit extensive vitreous seeding. The indications and contraindications for cryotherapy and photocoagulation have been more clearly delineated. The role of chemotherapy is being evaluated in the treatment of primary retinoblastoma and for metastatic disease. New breakthroughs in genetic research are being applied to clinical genetic counseling. The prognosis for life and for preservation of vision has improved greatly in recent years. 相似文献