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21.
An early accurate diagnosis of subungual melanoma depends upon an alert podiatric physician. Clinically, the lesion is often easily misdiagnosed and mistreated because of its resemblance to benign nail conditions. This paper discusses the incidence, histology, clinical findings, diagnosis, and treatment of this malignant lesion. An illustrative case report is presented.  相似文献   
22.
Protein synthesis in skeletal muscle is known to decrease during contractions but the underlying regulatory mechanisms are unknown. Here, the effect of exercise on skeletal muscle eukaryotic elongation factor 2 (eEF2) phosphorylation, a key component in protein translation machinery, was examined. Eight healthy men exercised on a cycle ergometer at a workload eliciting ∼67% peak pulmonary oxygen consumption     with skeletal muscle biopsies taken from the vastus lateralis muscle at rest as well as after 1, 10, 30, 60 and 90 min of exercise. In response to exercise, there was a rapid (i.e. < 1 min) 5- to 7-fold increase in eEF2 phosphorylation at Thr56 that was sustained for 90 min of continuous exercise. The in vitro activity of skeletal muscle eEF2 kinase was not altered by exercise indicating that the increased activity of eEF2 kinase to eEF2 is not mediated by covalent mechanisms. In support of this, the increase in AMPK activity was temporally unrelated to eEF2 phosphorylation. However, skeletal muscle eEF2 kinase was potently activated by Ca2+–calmodulin in vitro , suggesting that the higher eEF2 phosphorylation in working skeletal muscle is mediated by allosteric activation of eEF2 kinase by Ca2+ signalling via calmodulin. Given that eEF2 phosphorylation inhibits eEF2 activity and mRNA translation, these findings suggest that the inhibition of protein synthesis in contracting skeletal muscle is due to the Ca2+-induced stimulation of eEF2 kinase.  相似文献   
23.
Clinical aspects of pelvic inflammatory disease   总被引:2,自引:0,他引:2  
Pelvic inflammatory disease (PID) is a common and poorly managed condition. Untreated or inadequately treated, it leads to tubal infertility, ectopic pregnancy and chronic pelvic pain. Diagnostic difficulties are compounded by the wide variety of clinical presentations and the insensitivity and poor specificity of laboratory tests. Better recognition of mild and atypical disease needs a high index of suspicion whenever young, sexually active women present with gynaecological symptoms. Laparoscopy supplemented by microbiological tests and fimbrial minibiopsy should be regarded as the diagnostic 'gold standard' for research studies; new studies are required to identify techniques which might reduce under- and over-diagnosis. Early treatment reduces the risk of an adverse effect on fertility. Any therapeutic regimen selected should be effective against the common aetiological agents Chlamydia trachomatis, Neisseria gonorrhoeae, genital mycoplasmas and aerobic and anaerobic bacteria. Since at least 60% of cases of PID can be attributed to infection with a sexually transmitted organism, partner notification forms an essential part of management.   相似文献   
24.
Impalement injuries to the upper extremity are rare. A case is described of penetration of a 10 x 3.5-inch fence post into the left shoulder of a 16-year-old boy, pinning the shoulder to the chest wall. Sequelae of potential serious brachioplexus, vascular, and intrathoracic injuries are reviewed. The author presents a systematic treatment approach to the assessment, extrication, and microneurovascular repair of damaged structures, and to soft tissue reconstruction following massive foreign body injuries.  相似文献   
25.
Lymphocytes were cultured from cardiac biopsies following heart transplantation using interleukin-2-conditioned medium. Using the technique of limiting dilution analysis the frequency of donor specific cytotoxic T lymphocytes was measured in cells cultured from biopsies and compared with that in peripheral blood lymphocytes taken at the same time as the biopsy. The graft cell population showed a considerably higher frequency of donor-specific CTL when compared with the PBL. CTL frequencies in the graft cells were always higher against the donor than against third-party cells. These data demonstrate that there was either selective sequestration or selective expansion of donor-reactive T cells in the heart following cardiac transplantation. These results emphasize the need to investigate more closely the events occurring in the heart, and may explain the lack of specificity and sensitivity in immune monitoring (IM) or cytoimmune monitoring (CIM) seen in many centers.  相似文献   
26.
Epidermal growth factor (EGF)-related polypeptides may be involved in the growth of human prostate cancer cells, and in the androgen stimulation of hormone-responsive prostatic carcinomas. We have shown that androgen-responsive LNCaP cells, like the autonomous DU 145 human prostate cancer cell line, synthesize and secrete EGF and related polypeptides, including immunoreactive transforming growth factor-alpha (TGF-alpha). As determined by radioimmunoassay, intracellular EGF levels were approximately 100 times those of TGF-alpha, but together these accounted for less than half of the total EGF-like polypeptides detected in a radioreceptor assay. Although LNCaP cell growth was stimulated by dihydrotestosterone (DHT), there was no evident effect on immunoreactive EGF levels in the medium after correction for cell number. Moreover, metabolic labeling experiments showed no effect of the androgen on EGF synthesis by LNCaP cells. Gel filtration chromatography of conditioned medium showed both high molecular weight species and the mature 6,000 dalton form of immunoreactive EGF. We conclude that although LNCaP prostate cancer cell growth is stimulated by DHT, it is unlikely that it is mediated directly via increased EGF synthesis by the tumor cells.  相似文献   
27.
Pharmacokinetic profiles were obtained for 16 heart or lung recipients following the administration of identical doses of cyclosporin as oral solution and capsules on consecutive days. A comparison of pharmacokinetic parameters (AUC, Cmax, Cmin and tmax) showed that there were no significant differences between the two formulations except for the tmax, which was significantly longer for the capsules. The mean variation in day-to-day trough levels produced by the two different forms was 25.6%. A retrospective study was carried out of consecutive cyclosporin levels in patients at steady state on oral solution. The mean variation in day-to-day trough levels was 32.3%. This was not significantly different from the variation in consecutive trough levels seen in the oral solution/capsule comparison. This study shows that cyclosporin capsules can be substituted for oral solution without causing acute changes in cyclosporin blood levels, and that the pharmacokinetics of the two formulations are similar.This work was carried out in partial fulfillment of the requirements for the Master of Science Degree in Clinical Pharmacy, University of London  相似文献   
28.
Acute treatment of common marmosets with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) caused an initial profound akinesia and other motor deficits. However, over the following months akinesia gradually disappeared although the animals remained clumsy and poorly coordinated. At 10 days following MPTP treatment there was a profound decrease in the dopamine, HVA and DOPAC content of the caudate nucleus, putamen and nucleus accumbens. By 3-4 months following MPTP treatment the animals had largely recovered from their akinesia, but the caudate nucleus and putamen dopamine, HVA and DOPAC content remained low. In contrast, the dopamine content of the nucleus accumbens had returned towards normal and the metabolite levels were higher than at 10 days. No overall alterations in 5HT or 5HIAA levels were observed at either time point. The transient and reversible nature of dopamine loss in the nucleus accumbens may contribute to the initial profound akinesia exhibited by common marmosets treated with MPTP. The restoration of dopamine levels in the nucleus accumbens may be partially responsible for the subsequent recovery of motor function that occurs in MPTP-treated marmosets.  相似文献   
29.
Long-term treatment of mouse cancer cells with interferon-alpha (IFN-alpha) converts parental B16 melanoma cells to B16alpha vaccine cells. Inoculation of syngeneic mice with B16alpha vaccine cells triggers immunity to the parental B16 tumor that is mediated by host macrophages, T cells, and natural killer (NK) cells. Lymph node cells from mice inoculated with irradiated B16alpha vaccine cells, but not with irradiated parental cells, proliferate when cultured in vitro, suggesting long-term in vivo activation of lymphoid cells. Long-term IFN-alpha treatment of B16alpha vaccine cells induced both interleukin-15 (IL-15) mRNA and IL-15 protein. The bulk of the induced IL-15 remained cell associated, either cytoplasmic or associated with the cell membrane. Immunofluorescence microscopy studies showed that the cell-associated IL-15 was broadly distributed throughout the cytoplasm. These observations suggest that long-term IFN-alpha treatment may induce primarily the truncated isoform of IL-15. Vaccination with irradiated B16alpha vaccine cells may promote tumor immunity by releasing high levels of cell-associated IL-15 when spontaneously lysed or directly killed by innate immune cells. The release of accumulated cell-associated IL-15 may then trigger a host T cell response to tumor antigens and cause host development of immunity to the B16 tumor cells.  相似文献   
30.
U Rose 《Arzneimittel-Forschung》1989,39(11):1393-1398
The anellated dihydropyridines 4a-l can be gained by Hantzsch-like synthesis from 5,5-dimethylcyclohexanedione (1), the aromatic aldehydes 2a-l and methyl-beta-aminocrotonate (3). Cyclisation of the side chains with bromosuccinimide or pyridiniumbromideperbromide leads to the octahydrofuro[3,4-b]chinoline-diones 4m-p. Structures of type 4 are characterized by the spectroscopic data. Positive inotropic effects, caused by calcium agonism, are exerted by the tested substances at the isolated, electrically stimulated left guinea pig atrium, 4j being the most potent with an intrinsic activity of 0.79, compared with ethyl 4-[2-(difluoromethoxy)phenyl]-1, 4,5,7-tetrahydro-2-methyl-5-oxo-furo[3,4-b]pyridine-3-carboxylate. BaCl2-induced contractions at the guinea pig ileum are suppressed dose-dependently.  相似文献   
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