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91.
The role of nerve growth factor (NGF), a potent mediator acting in the development and differentitation of both neuronal and immune cells, was examined in a mouse model of allergic asthma. NGF-positive cells were detected in the inflammatory infiltrate of the lung and enhanced levels of NGF were detected in serum and broncho-alveolar lavage fluids. Mononuclear cells in inflamed airway mucosa as well as broncho-alveolar macrophages were identified as one source of NGF production. Splenic mononuclear cells from allergen-sensitized mice produced NGF in response to allergen. They responded to exogenously added NGF with a dose-dependent increase in IL-4 and IL-5 production and augmented IgE and IgG1 synthesis. In contrast, IFN-γ and IgG2a levels remained unaffected. The effects were NGF specific, since they could be blocked by an anti-NGF-antibody. Nasal application of anti-NGF to allergen-sensitized mice significantly reduced IL-4 and prevented development of airway hyperreactivity. These results show that allergic airway inflammation is accompanied by enhanced local NGF production that acts as an amplifier for Th2 effector functions and plays an important role in the development of airway hyperreactivity. Therefore it is suggested that NGF may serve as a link between the immune and nerve system.  相似文献   
92.
Octylcyanoacrylate tissue adhesive glue is a wound closure device recently approved by the U.S. Food and Drug Administration. Few complications have been reported regarding the liquid adhesive entering the wound. The following report involves a patient who developed intestinal occlusion secondary to octylcyanoacrylate used for skin closure in laparoscopic surgery.  相似文献   
93.
Logrono R  Bhanot P  Chaya C  Cao L  Waxman I  Bhutani MS 《Cancer》2006,108(4):257-266
BACKGROUND: Gastrointestinal stromal tumors (GISTs) recently have been distinguished morphologically, immunohistochemically, and genetically from other gastrointestinal-tract spindle cell neoplasms. The objective of this study was to correlate clinical and imaging findings with morphology and immunohistochemistry to diagnose GISTs and to differentiate them from other spindle cell lesions in the gastrointestinal tract. METHODS: The authors reviewed 9 patients who had tumors that were diagnosed as GIST by image-guided and endosonographic-guided fine-needle aspiration (FNA) with or without core biopsy (7 stomach tumors and 2 intraabdominal tumors). The male:female ratio was 3:6, and the patients ranged in age from 38 years to 80 years. Onsite evaluation, preliminary cytologic evaluation, and immunohistochemistry were provided for 6 patients. Immunostains were performed, depending on sample size, on aspirates and/or core biopsies. RESULTS: On imaging studies, most tumors were smooth and homogenous, consistent with GIST. Tumors ranged in size from 1.8 cm to 22 cm. The largest neoplasm showed solid/cystic and necrotic components. Aspirates consisted of spindle cell, neoplastic proliferation arranged in fascicles that exhibited focal, nuclear palisading; indistinct, cytoplasmic borders; and no significant atypia or mitosis. Focal epithelioid changes or cytologic atypia and mitoses were observed in 2 tumors. Immunostains revealed tumor expression of CD117 and/or CD34 in 5 of 6 tumors, expression of actin in 3 of 6 tumors, and expression of desmin in 1 of 6 tumors. All tumors were diagnosed as GIST (or consistent with GIST for tumors that lacked immunochemical analysis). Five patients underwent surgical excision, and the GIST diagnosis was confirmed in 3 patients, whereas 1 tumor proved to be neurofibroma, and another tumor was leiomyoma. No surgical follow-up was available for the remaining 4 patients, who had imaging and morphologic findings consistent with GIST. CONCLUSIONS: In the setting of consistent clinical and radiologic findings, the combined use of cytomorphology and immunohistochemistry on FNA and/or core biopsy in most instances provides a reliable pathologic diagnosis of GIST. The need of sufficient material for performing ancillary studies and the usual impossibility of excluding malignancy are limitations of FNA cytology of GIST.  相似文献   
94.
Blood lymphocytes from rats bearing transitional cell carcinoma (TCC) of the bladder were studied for their cytotoxicity in vitro against xenogeneic YAC-1 target and against syngeneic TCC cells. Control lymphocytes were obtained from age and sex-matched syngeneic rats. The following differences were observed: (I) lymphocytes from TCC-bearing rats were cytotoxic to syngeneic TCC target cells whereas those from control rats were not; (2) lymphocytes from TCC-bearing and control rats were cytotoxic to NK sensitive YAC-I cells; however, NK cells from TCC-bearing rats were more adherent to nylon wool-columns than NK cells from control rats. The adherent and non-adherent cells from TCC-bearing rats were both cytotoxic to syngeneic TCC target cells. Levamisole treatment of effector cells from TCC-bearing rats did not affect the NK activity, yet it increased the cytotoxicity of non-adherent cells on TCC target cells. Treatment of the adherent cells with poly-l:poly-C increased slightly their NK activity on YAC-I cells and their anti-TCC cytotoxicity. However, a marked increase in the cytotoxicity by both adherent and non-adherent cell fractions was observed on TCC target cells pretreated with poly-l:poly-C. A disease-related cytotoxicity of lymphocytes from rats bearing TCC has been observed. Treatment of TCC target cells with poly-l:poly-C increased their susceptibility to lysis by the activated effector cells.  相似文献   
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97.
Assess computed tomography (CT) imaging characteristics after percutaneous cryotherapy for lung cancer.A retrospective IRB-approved analysis of 40 patients who underwent nonsurgical treatment for primary stage 1 lung cancer performed from January 2007 to March 2011 was included in this study. All procedures were performed using general anesthesia and CT guidance. Follow-up imaging with CT of the chest was obtained at 1 month, 3 months, 6 months, and 12 months postprocedure to evaluate the ablated lung nodule. Nodule surface area, density (in Hounsfield units), and presence or absence of cavitations were recorded. In addition, the degree of nodule enhancement was also recorded. Patients who were unable to obtain the aforementioned follow-up were excluded from the study.Thirty-six patients underwent percutaneous cryoablation with men to women ratio of 75% with mean age for men 74.6 and mean age for women 74.3 years of age. The average nodule surface area preablation and postcryoablation at 1-, 3-, 6-, and 12-month follow-ups were 2.99, 7.86, 3.89, 3.18 and 3.07cm2, respectively. The average precontrast nodule density before cryoablation was 8.9 and average precontrast nodule density postprocedure at 1, 3, 6, and 12 months follow-ups were 8.5, −5.9, −9.4, and −3.8 HU, respectively. There is increased attenuation of lung nodules over time with an average postcontrast enhancement of 11.4, 18.5, 16.1, and 25.7 HU at the aforementioned time intervals. Cavitations occurred in the cryoablation zone in 53% (19/36) of patients. 80.6% (29/36) of the cavitations in the cryoablation zone resolved within 12 months. Four patients (11%) had recurrence of tumor at the site of cryoablation and none of the patients had satellite or distant metastasis.Our study shows that patients who underwent cryotherapy for lung nodules treatment had characteristic changes on follow-up CT including. The surface area of the nodule increases at the 1-month follow-up with subsequent gradual decrease in the surface area. Decreased nodule density (Hounsfield units) at each interval follow-up is associated with complete ablation of the lung cancer whereas increasing nodule density was suggestive of recurrence. Cavity formation within the region of the ablated nodule, most of which typically resolved within the first 3 to 6 months. Nodule enhancement is difficult to assess because of the limited data sets that are available.  相似文献   
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99.
The relationship between elders’ marital status and length of widowhood, as well as other personal and familial resources and the sense of meaning in life, as defined by logotherapy, was tested among 180 Israeli elderly community dwellers aged 64–95. Results show that an event such as late-life widowhood can create a loss of the sense of meaning in life. In addition, a significant difference was found between married and recently widowed elders in relation to meaning in life. Other variables that affected and explained meaning in life were subjective health, education, the quality of social support relationships, and activity level. The results support Frankl’s logotherapy approach, underscoring the importance of helping older people in general, and the widowed elders in particular, to discover and create new life meanings.
Ariela LowensteinEmail:
  相似文献   
100.
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