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51.
While depressive symptomatology is typically discussed in terms of a cognitive-behavioral-affective triad, research and clinical work has tended to focus primarily on thought and behavior. Disengagement from incentives in depression should also be examined explicitly from the affective sphere. In the present study, the semantic differential technique was used to map the reactions of depressed and nondepressed college students to global concepts of a self-referent (self, past, future) versus external (friends, family, school) nature. Findings revealed that depressed subjects rated all concepts significantly less potent, less active, and less evaluatively positive as compared to their nondepressed peers.  相似文献   
52.
Ultrasound: biological effects and industrial hygiene concerns   总被引:1,自引:0,他引:1  
Due to the increased use of high intensity ultrasonic devices, there is now a greater risk of worker exposure to ultrasonic radiation than there was in the past. Exposure to high power ultrasound may produce adverse biological effects. High power ultrasound, characterized by high intensity outputs at frequencies of 20-100 kHz, has a wide range of applications throughout industry. Future applications may involve equipment with higher energy outputs. Contact ultrasound, i.e., no airspace between the energy source and the biological tissue, is significantly more hazardous than exposure to airborne ultrasound because air transmits less than one percent of the energy. This paper discusses biological effects associated with overexposure to ultrasound, exposure standards proposed for airborne and contact ultrasound, industrial hygiene controls that can be employed to minimize exposure, and the instrumentation that is required for evaluating exposures.  相似文献   
53.
We studied the degenerative "ancient" changes in 19 cases of benign cutaneous schwannoma (BCS). Using conventional and immunohistochemical stains, we found (a) degenerative changes in 15 of 19 BCS; (b) prominent vascular abnormalities in 11 of 15 BCS; and (c) cytologic atypia in 15 of 19 BCS, without mitotic figures. We concluded that (1) degenerative, i.e., "ancient" changes are common in BCS and are qualitatively similar to those described in cellular schwannoma; (2) vascular abnormalities may be related to these degenerative changes; (3) cytologic atypia is commonly associated with "ancient" changes in BCS, but BCS is less cellular and has few if any mitotic figures as opposed to cellular schwannomas; and (4) the changes in "ancient" schwannoma do not indicate a "cellular" schwannoma.  相似文献   
54.
55.
(Formyl-sarcosine)1-LH-RH (I), (acetyl-sarcosine)1-LH-RH (II), (2-pyrrolidone-4-carboxylic acid)1-LH-RH (III), (N-methyl-2-pyrrolidone-4-carboxylic acid)1-LH-RH (IV, hydroxyproline1-LH-RH (V) and (cyclopentane-carboxylic acid)1-LH-RH (VI) were synthesized by solid phase methods on a benzhydrylamine resin support. Peptides I-IV were assayed for LH- and FSH-releasing activity over a 4-h period after subcutaneous injection into immature male rats in order to detect any prolongation of activity. The peptides were found to have the following integrated LH-releasing activities compared with LH-RH: I, 64%; II, 72%; III, 19%; IV, 58%. None of the peptides were found to be longer acting than LH-RH. Peptides V and VI were far less active, 0.001% and 1.4%, respectively.  相似文献   
56.
C Milos  S Karoly 《Orvosi hetilap》1975,116(19):1094-1097
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57.
The receptor protein tyrosine phosphatase beta (RPTPbeta) is a functional biomarker for several solid tumor types. RPTPbeta expression is largely restricted to the central nervous system and overexpressed primarily in astrocytic tumors. RPTPbeta is known to facilitate tumor cell adhesion and migration through interactions with extracellular matrix components and the growth factor pleiotrophin. Here, we show that RPTPbeta is expressed in a variety of solid tumor types with low expression in normal tissue. To assess RPTPbeta as a potential target for treatment of glioblastoma and other cancers, antibodies directed to RPTPbeta have been developed and profiled in vitro and in vivo. The recombinant extracellular domain of human short RPTPbeta was used to immunize mice and generate monoclonal antibodies that selectively recognize RPTPbeta and bind to the antigen with low nanomolar affinities. Moreover, these antibodies recognized the target on living tumor cells as measured by flow cytometry. These antibodies killed glioma cells in vitro when coupled to the cytotoxin saporin either directly or via a secondary antibody. Finally, in vivo studies showed that an anti-RPTPbeta immunotoxin (7E4B11-SAP) could significantly delay human U87 glioma tumors in a mouse xenograft model. Unconjugated 7E4B11 provides a modest but statistically significant tumor growth delay when delivered systemically in mice bearing U87 glioma tumors.  相似文献   
58.
In 1925, Calvé described vertebra plana as an aseptic necrosis of bone involving a single vertebral body of the spinal column. This theory was set aside in 1954 by Compere, who concluded that vertebra plana is caused by eosinophilic granuloma and not by osteochondritis as suggested by Calvé. It has been well documented in literature that many factors other than eosinophilic granuloma can cause vertebra plana-like destruction of the vertebral body. However, the definition of the terms was not clear, and there was no consensus on whether to call these cases vertebra plana or not. Some authors did, some did not. Anyhow, no publication so far has reported on osteochondritis as a rare cause of vertebra plana. The case of a 12-year-old girl, presented here by the authors, suggests this explanation. Some important conclusions can be drawn from this regarding the nomenclature, the diagnosis, and the therapy.  相似文献   
59.
BACKGROUND: Receptors for luteinizing hormone-releasing hormone (LHRH) on human prostate cancers can be used for targeted chemotherapy with cytotoxic analogs of LHRH, such as AN-207, which consists of superactive doxorubicin derivative 2-pyrrolino doxorubicin (AN-201) linked to carrier [D-Lys6] LHRH. METHODS: The effects of AN-207 and AN-201 were investigated in DU-145 androgen independent and LuCaP-35 androgen sensitive human prostate cancers xenografted into nude mice. Toxicity was evaluated by survival rates, changes in body weights, and leukocyte counts. LHRH receptors on DU-145 and LuCaP-35 tumors were evaluated by radioreceptor assays and RT-PCR. The effects on apoptosis and cell proliferation were investigated by histology and evaluation of apoptotic oncogenes Bcl-2 and Bax by Western Blot analysis. RESULTS: AN-207 inhibited growth of DU-145 tumors significantly by 75% (P < 0.01) and LuCaP-35 human prostate cancers by 80% (P < 0.01), and was less toxic than AN-201. Receptors for LHRH were expressed on DU-145 and LuCaP-35 tumors. Blockade of LHRH receptors with LHRH agonist Triptorelin nullified the effects of AN-207. Treatment with AN-207, but not with AN-201, decreased Bcl-2/Bax ratio in DU-145 tumors and Bcl-2 in LuCaP-35 tumors indicating an increase in apoptotic activity. AN-207, but not AN-201, decreased cell proliferation in both models. CONCLUSIONS: Targeted chemotherapy with AN-207 could be considered for treatment of advanced prostate cancer.  相似文献   
60.
Marshman L  David KM 《Journal of neurosurgery. Spine》2006,4(6):516-7; author reply 517
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