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221.
BACKGROUND. The interface between the subspecialties of dermatologic surgery and oculoplastic surgery is broad. However, there are many commonly seen oculoplastic conditions that are not foremost in the mind of the dermatologic surgeon. OBJECTIVES. Common oculoplastic problems are detailed in this article and should provide the reader with a basis for understanding the wide spectrum of oculoplastic problems encountered in practice.  相似文献   
222.
Low-temperature (LT) induced genes of the Wcs120 family in wheat (Triticum aestivum) were mapped to specific chromosome arms using Western and Southern blot analysis on the ditelocentric series in the cultivar Chinese Spring (CS). Identified genes were located on the long arms of the homoeologous group 6 chromosomes of all 3 genomes (A, B, and D) of hexaploid wheat. Related species carrying either the A, D, or AB genomes were also examined using Southern and Western analysis with the Wcs120 probe and the WCS120 antibody. All closely related species carrying one or more of the genomes of hexaploid wheat produced a 50 kDa protein that was identified by the antibody, and a Wcs120 homoeologue was detected by Southern analysis in all species. In the absence of chromosome arm 6DL in hexaploid CS wheat no 50 kDa protein was produced and the high-intensity Wcs120 band was missing, indicating 6DL as the location of Wcs120 but suggesting silencing of the Wcs120 homoeologue in the A genome. Levels of proteins that cross-reacted with the Wcs120 antibody and degrees of cold tolerance were also investigated in the Chinese Spring/Cheyenne (CS/CNN) chromosome substitution series. CNN chromosome 5A increased the cold tolerance of CS wheat. Densitometry scanning of Western blots to determine protein levels showed that the group 5 chromosome 5A had a regulatory effect on the expression of the Wcs120 gene family located on the group 6 chromosomes of all three hexaploid wheat genomes.  相似文献   
223.
BACKGROUND: Balloon injury models in rat have shown enhanced expression of ACE in the developing neointima. However, neointimal lesions in human coronary arteries are complex due to atherosclerosis and different types of wall laceration. This study was designed to investigate whether ACE is present in the neointima of humans, including patients with restenosis after percutaneous transluminal coronary angioplasty (PTCA). METHODS AND RESULTS: Thirty-seven sites with angioplasty injury, obtained at autopsy, were studied using immunocytochemical techniques. Sites with injury limited to a fibrous plaque and those with injury extending into the media (<2 months after PTCA) showed fibrocellular repair tissue composed mainly of smooth muscle cells that were distinctly positive for ACE. In cellular reactions at the site of injury limited to the atheromatous plaque (<2 months after PTCA), the expression of ACE appeared first in accumulated macrophages; once smooth muscle cells appeared in the repair tissue, they also expressed ACE. At a later stage (3 months after PTCA), the number of cells with ACE expression decreased markedly; from 7 months on, ACE was no longer expressed within the repair tissue. Basically, there were no differences with regard to ACE expression during the healing process after PTCA between segments with and those without angiographic evidence of restenosis. CONCLUSIONS: These results show that PTCA injury in humans results in upregulation of ACE at sites of active repair and, therefore, ACE could play an important role as one of the mediators of the healing process after PTCA.  相似文献   
224.
During recent years the world has experienced the reemergence of old communicable diseases and the emergence of new ones caused by novel pathogens such as the HIV virus and Borrelia burgdorferi. The problem consists mostly in the reemergence of old diseases but specially in industrialized countries new pathogens have also been described. Although the emergence of these infections in rare instances is due to genetic changes of pathogens to more virulent forms, most commonly they are due to changes in the environment and the host. Rapidly deteriorating living standards, disintegration of sanitation and public health infrastructure, cultural changes, migration and variations in behavior are some of the factors involved in the worldwide increase of infectious diseases. The degradation of natural habitats including forests and marine niches accompanied by climatic changes, are also playing an increasing role in the detrimental evolution of these diseases. The global emergence of these diseases calls into question the doctrine of epidemiological transition and directs us to scrutinize the paradigm that bases the prevention of these diseases solely on vaccination. The current situation also highlights the limitations of classical epidemiology in dealing with unexpected problems, and strongly suggests that this discipline should incorporate into its analysis findings from other fields, including ecological, climatological, and economical information. As most of the negative social and economical developments that impinge on the detrimental evolution of these diseases are increasing world-wide, it can be predicted that the problems posed by these infections will continue and perhaps worsen in the near future.  相似文献   
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Pure autonomic failure is characterized by orthostatic hypotension, sweating disorder, urinary incontinence, and syncope. A 64 year-old man with pure autonomia failure was scheduled for suprapubic prostatectomy. We monitoring direct arterial pressure and inserted pulmonary artery catheter prior to the induction of anesthesia. General anesthesia was induced with diazepam 10 mg, fentanyl 0.3 mg, and vecuronium 8 mg for tracheal intubation. Anesthesia was maintained with sevoflurane (0.2-1.5%), 60% nitrous oxide in oxygen supplemented with intermittent epidural anesthesia. During anesthesia, blood loss was immediately replaced with banked blood because autonomic failure could not compensate hypovolemia well. Epidural anesthesia in this patient was considered to cause less hypotension than in patients with normal autonomic function. Therefore, we think epidural anesthesia is a useful anesthesia method for patients with pure autonomic failure. The emergence from anesthesia was smooth and no complications were seen during the perioperative period.  相似文献   
227.
We have previously described an in vitro sensitization (IVS) procedure which enabled the generation of therapeutic T cells from tumor-bearing mice for adoptive immunotherapy. The procedure involved culture of tumor-draining lymph node (TDLN) cells with irradiated tumor in the presence of interleukin-2 (IL-2). The availability of many recombinant cytokines affords an opportunity to examine their effects on the immune response to tumor. In this study, we investigated the effect of tumor necrosis factor-alpha (TNF alpha) on the generation and function of IVS cells utilized in adoptive immunotherapy of the murine MCA 106 sarcoma. TNF alpha administered iv at nontherapeutic doses was found to enhance the antitumor efficacy mediated by IVS cells plus IL-2 in the treatment of pulmonary metastases. In contrast, TNF alpha administration to mice bearing progressive footpad tumors had inhibitory effects on the sensitization of tumor-reactive cells in TDLN since IVS cells generated from these animals displayed a diminished antitumor effect. This effect appeared to be due to a reduced number of tumor-reactive lymphoid cells in the TDLN since TNF alpha added to IVS cultures did not alter the antitumor efficacy of the resultant IVS effector cells. These findings indicate the divergent effects of TNF alpha on the immune response to tumor and adoptive immunotherapy with IVS cells.  相似文献   
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229.
The controversy continues over the appropriate use of vaginal hysterectomy for many indications that were previously treated only with abdominal or laparoscopic methods. Current outcomes data have pointed up the need for established guidelines to ensure that patients receive appropriate surgical treatment that is most cost-effective and that meets the standard of quality care. Dr Kovac reviews recent data regarding the various surgical options for hysterectomy and offers guidelines based on objective pathologic criteria.  相似文献   
230.
OBJECTIVE: To determine whether parapapillary chorioretinal atrophy in patients with ocular hypertension remained stationary or progressed along with glaucomatous optic nerve damage. METHODS: The morphometric parameters and progression of parapapillary atrophy were retrospectively investigated, using serial photographs, in 350 eyes of 175 patients with ocular hypertension. The association of parapapillary atrophy progression with subsequent glaucomatous conversion and with other baseline patient- and eye-specific characteristics was analyzed. RESULTS: Progression in the area and extension of parapapillary atrophy before noticeable optic disc or visual field changes was observed in 48 (49.0%) of 98 eyes that converted to glaucoma, while parapapillary atrophy progression was noted in 25 (9.9%) of 252 ocular hypertensive eyes that did not develop glaucomatous damage (P<.001). The predictive sensitivity and specificity of this observation were 49% and 90%, respectively. In a logistic multiple regression model, the progression of parapapillary atrophy was associated with a family history of glaucoma (odds ratio, 2.7) and the initial size of zone beta (odds ratio, 1.64, for an increase of 0.10 of the zone beta area-disc area ratio). CONCLUSION: The progression of parapapillary chorioretinal atrophy may be an early glaucomatous finding in some patients with ocular hypertension.  相似文献   
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