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61.
Narrow-band ultraviolet B (UVB) is a newer treatment modality for photoresponsive skin diseases. Since its introduction, dermatologists continue to use it for a myriad of dermatoses. Polycythemia vera is one cause of intractable pruritus that has recently been treated successfully with narrow-band UVB. We describe the case of a 77-year-old Caucasian male with a 4-year history of polycythemia vera complicated by intractable pruritus. Narrow-band UVB was successfully used to treat his pruritus. The patient noted an improvement in pruritus within the first four treatments and almost complete resolution after 18 treatments.  相似文献   
62.
Ex vivo T cell depletion of donor marrow grafts in humans and mice has virtually eliminated severe graft-versus-host disease (GVHD). However, as a consequence of T cell depletion, sustained donor cell engraftment is likely compromised. Since the majority of T cell depletion techniques also deplete natural killer (NK) cells, we investigated the role of donor NK cells in engraftment and GVHD in a murine model. Using a monoclonal antibody directed against an NK-specific epitope, we have selectively depleted NK cells while preserving donor marrow T cells. In an established model of engraftment, selective NK depletion demonstrated that removal of donor NK cells did not impair the engraftment process under conditions in which donors and recipients are major histocompatibility complex-disparate. In contrast, recipients of anti-Thy 1.2 plus complement (C')-treated marrow grafts had a significantly higher incidence of either partial engraftment or graft rejection as compared with recipients of selective NK-depleted donor grafts or control grafts. In addition, we have observed that NK-specific depletion of donor marrow/splenocyte inocula does not alter the incidence of GVHD. Recipients of NK-depleted donor grafts developed lethal acute GVHD, whereas recipients of anti-Thy 1.2-depleted donor grafts did not (P less than 0.0001). Interestingly, NK 1.1-depleted donor graft recipients had a significantly increased mortality in comparison with control groups receiving C'-treated grafts (P = 0.04) or anti-Thy 1.2 plus C'-treated grafts (P less than 0.05). Thus, NK depletion may reduce immunosurveillance, thereby increasing the risk of posttransplant infection. We conclude from these results that donor NK cells play an insignificant role in engraftment as well as in the afferent phase of GVHD, but may be important in immunosurveillance when murine bone marrow is transplanted across the major histocompatibility barrier.  相似文献   
63.
64.
This research aimed to investigate the changes in ethical issues in everyday clinical practice recognized by critical care nurses during two observation periods. We conducted a retrospective analysis of data obtained by prospective questionnaire surveys of nurses in the intensive care units (ICU) of a tertiary university-affiliated hospital in Seoul, Korea. Data were collected prospectively during two different periods, February 2002-January 2003 (Period 1) and August 2011-July 2012 (Period 2). Significantly fewer cases with ethical issues were reported in Period 2 than in Period 1 (89 cases [2.1%] of 4,291 ICU admissions vs. 51 [0.5%] of 9,302 ICU admissions, respectively; P < 0.001). The highest incidence of cases with identified ethical issues in both Periods occurred in MICU. The major source of ethical issues in Periods 1 and 2 was behavior-related. Among behaviorrelated issues, inappropriate healthcare professional behavior was predominant in both periods and mainly involved resident physicians. Ethical issue numbers regarding end-oflife (EOL) care significantly decreased in the proportion with respect to ethical issues during Period 2 (P = 0.044). In conclusion, the decreased incidence of cases with identified ethical issues in Period 2 might be associated with ethical enhancement related with EOL and improvements in the ICU care environment of the studied hospital. However, behaviorrelated issues involving resident physicians represent a considerable proportion of ethical issues encountered by critical care nurses. A systemic approach to solve behavior-related issues of resident physicians seems to be required to enhance an ethical environment in the studied ICU.

Graphical Abstract

相似文献   
65.

Objectives

To evaluate the effect of obstructive sleep apnea (OSA) surgery on long-term (5-year) subjective outcomes, including sleep disordered breathing (SDB) symptoms and other complications, in patients with OSA.

Methods

We enrolled patients who underwent diagnostic polysomnography for OSA between January 2006 and December 2006 in ten hospitals. Patients either were treated for OSA or were not treated for OSA. All patients completed a brief telephone survey regarding their SDB signs and symptoms (e.g., snoring, apnea, nocturnal arousals, and daytime sleepiness), positive airway pressure (PAP) compliance, and any adverse effects of either the surgery or PAP. A positive subjective outcome for either surgery or no treatment was taken to be the alleviation of apnea, defined as a ≥50% increase in score. A positive subjective outcome (compliance) for PAP was defined as a PAP usage of ≥4 hours per night and ≥5 days per week.

Results

A total of 229 patients were included in this study. Patients were divided into three groups: a surgery group (n=87), a PAP group (n=68), and a control (untreated) group (n=74). The surgery group exhibited significant improvement in all SDB symptoms compared with the control group. The long-term subjective outcomes of the surgery (52.9%) and PAP (54.4%) groups were significantly better than those of the control group (25.0%). The subjective outcome of the surgery group was not significantly different from that of the PAP group. The overall surgical complication rate was 23.0% (20 of 87) in the surgery group, and 55.0% (22 of 40) of all patients with PAP experienced adverse effects.

Conclusion

The extent of SDB symptoms was consistently improved in patients with OSA at 5 years postsurgery. Information about the potential long-term subjective outcomes should be provided to patients when considering surgery.  相似文献   
66.
Although the APC protein is known to participate in cellular proliferation and apoptosis, APC mutations have been thought to play a major role in the early stage of colorectal tumorigenesis. The somatic APC mutation of exon 15 was assessed to determine its impact on various stages of colorectal tumorigenesis. The colorectal neoplastic tissues of serial array studied included sporadic adenomas (group 1, n = 36), adenomas (group 2, n = 33), and carcinomas (group 3, n = 32) in the synchronous adenoma and carcinoma as well as sporadic carcinomas (group 4, n = 36). Aberrant DNA was detected by protein truncation test and confirmed by direct sequencing. The mutation prevalence was 36.1% in group 1, 45.5% in group 2, 59.4% in group 3, and 41.7% in group 4 with no differences among the groups. Among the 18 patients with synchronous adenoma and carcinoma, 9 had mutation in their adenomas and 12 in their carcinomas. The mutation loci and patterns did not differ in adenomas and carcinomas. Mutations in the mutation cluster region (MCR) were much more frequent than in the preceding region of MCR, i.e., 85.7% vs. 14.3%. The mutation prevalence of villous adenomas appeared greater than that of tubular adenoma (3/21 vs. 3/4). Predominant pathogenic mutations at MCR suggest that the APC mutation is implicated in all stages of colorectal tumorigenesis.  相似文献   
67.
68.
AIM: To study the clinical significance of minimal ascites, which was only defined by the CT and whose nature was not determined preoperatively, in the relationship with the peritoneal carcinomatosis. METHODS: The medical records and the dynamic CT films of 118 patients with gastric cancer were reviewed. Factors associated with peritoneal carcinomatosis were analyzed in 40 patients who had CT-defined ascites of which the nature was surgically confirmed. RESULTS: Only 12.5-25% of the CT-defined minimal ascites, whose volume was estimated to be less than 50 mL, were associated with peritoneal carcinomatosis. When the estimated CT-defined ascitic volume was 50 mL or more, peritoneal carcinomatosis was identified in 75-100%. When CT-defined lymph node enlargements were not found beyond the regional gastric area, perigastric invasions were not suspected, and the size of tumor was less than 3 cm, peritoneal carcinomatosis seemed significantly less accompanied at the univariate analysis. However, except for the minimal volume of CT-defined ascites in comparison with the mild or more, other factors were not confirmed multivariately. CONCLUSION: In the patients with gastric cancer, CT-defined minimal ascites alone is rarely associated with peritoneal carcinomatosis, if it does not accompany other signs suggestive of malignant seeding. Therefore, consideration of active curative resection should not be hesitated, if CT-defined minimal ascites is the only delusive sign.  相似文献   
69.
Effector memory T cells (TM) play a key role in the pathology of certain autoimmune disorders. The activity of effector TM cells is under the control of Kv1.3 ion channels, which facilitate the Ca2+ influx necessary for T cell activation and function, i.e. cytokine release and proliferation. Consequently, the knock-down of Kv1.3 expression in effector TM's may be utilized as a therapy for the treatment of autoimmune diseases. In this study we synthesized lipid unilamellar nanoparticles (NPs) that can selectively deliver Kv1.3 siRNAs into TM cells in vitro. NPs made from a mixture of phosphatidylcholine, pegylated/biotinylated phosphoethanolamine and cholesterol were functionalized with biotinylated-CD45RO (cell surface marker of TM's) antibodies via fluorophore-conjugated streptavidin (CD45RO-NPs). Incubation of T cells with CD45RO-NPs resulted into the selective attachment and endocytosis of the NPs into TM's. Furthermore, the siRNA against Kv1.3, encapsulated into the CD45RO-NPs, was released into the cytosol. Consequently, the expression of Kv1.3 channels decreased significantly in TM's, which led to a remarkable decrease in Ca2+ influx. Our results can form the basis of an innovative therapeutic approach in autoimmunity.  相似文献   
70.
Osteonecrosis of the femoral head (ONFH) is a devastating disease frequently leading to femoral head collapse and hip arthritis. Specifically, non-traumatic ONFH primarily affects young and middle-aged adults. Although compromised local circulation of the femoral head seems to be pathognomonic for the disease, the pathogenesis is perplexing and continues to be an area of scrutiny and research. Comprehension of the pathogenesis is of crucial importance for developing and guiding treatments for the disease. Therefore, we provide an up-to-date consensus on the pathogenesis of non-traumatic ONFH.  相似文献   
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