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排序方式: 共有2465条查询结果,搜索用时 31 毫秒
41.
Work stress,nonwork stress,and health 总被引:1,自引:0,他引:1
Susan Klitzman James S. House Barbara A. Israel Richard P. Mero 《Journal of behavioral medicine》1990,13(3):221-243
This paper examines the interface between work stress and nonwork stress and how it relates to health. Results indicate that the way people feel at work is largely a function of conditions at work. Similarly, the way people feel outside of work is largely a function of things that occur outside the job. Both work and nonwork stress are independently associated with physical and mental health, although the relationship between nonwork stress and health is slightly stronger. Excessive demands or stresses in one domain can interfere with life in the other. Such conflict operates equally in both directions. When present it can be an added source of stress and adversely affect health. Taken together these findings suggest that the stress people experience at work is not simply a reflection of their "personal problems." This has implications for the design of health promotion and stress prevention programs in the workplace. 相似文献
42.
A prospective study of biochemical changes after vertical banded gastroplasty for morbid obesity, in 94 patients (10 males
and 84 females, ages ranging from 18 to 59 years) has been carried out. Liver function tests and electrolyte estimations were
performed preoperatively, during hospitalisation for surgery, at 6 weeks and at 6 months postoperatively, and demonstrated
no significant changes in liver function in these patients 6 months after surgery. The study concludes that there is no increase
in the risk of liver damage or electrolyte disturbance after vertical gastroplasty, but that there may be subtle hepatic changes
present as gall bladder disease developed in 18 patients postoperation (19%). 相似文献
43.
Neurons from hypothalamic paraventricular nuclei (PVN) and supraoptic nuclei (SON) from postnatal day 6-8 rats were enzymatically dissociated and separately maintained in monolayer cultures for 14 days. The osmotic pressure of the culture medium, based on Neurobasal medium (Life Technologies), was varied (255, 300 and 330 mOsm/l) by adjustment using mannitol. The survival of oxytocin (OT), vasopressin (VP) and oxytocin-vasopressin (OT/VP) coexpressing neurons were studied under these varied conditions, and the identification of the cell phenotypes in the cultures was carried out by using double-label immunofluorescence. Under control osmolar conditions (300 mOsm/l) equivalent numbers of OT and VP neurons were found in the SON (P = 0.8398) and PVN (P = 0.4721) cultures. The OT neurons' survival did not change in 255 or 330 mOsm media in the SON cultures, but the VP neurons in the SON cultures were significantly increased in 255 mOsm/l medium as compared to control (300 mOsm/l) medium (P = 0.0088). No significant changes were found in VP neuron survival in SON cultures between the 300-330 mOsm/l media (P = 0.2372). Similar data were obtained for the VP neurons in PVN-derived cultures, but the OT neurons in these cultures survived significantly better at 300 mOs/l than at 255 mOsm/l (P<0.0001), but were not significantly different at 330 mOsm/l (P = 0.1208). In general, the VP neurons were more vulnerable than OT neurons to increases of culture medium osmolarity with respect to their survival. The number of OT/VP coexpressing neurons was greater in SON-derived cell cultures as compared to PVN-derived cell cultures, and their numbers were higher in the lower osmolarity media. The effects of adding brain-derived neurotrophic factor (BDNF) to the culture medium on survival were determined. BDNF significantly increased the numbers of all three types of neurons in both PVN and SON cell cultures (P = 0.0001-0.0060). The phenotypically identified cells, cultured in the 300 mOsm/l medium, responded by depolarization or hyperpolarization when transferred to hypertonic or hypotonic perfusion salines, respectively. 相似文献
44.
House P Barry C Morgan W Sumner C 《Australian and New Zealand journal of ophthalmology》1999,27(5):301-305
PURPOSE: To report a commonly occurring change on the anterior surface of the Acrysof intraocular lens which is presumed to be due to the proliferation of lens epithelial cells from the capsulo-rhexis margin. METHOD: Forty-one consecutive cases (31 patients) of Acrysof intraocular lens implantation were followed prospectively. Clinical charts were reviewed for changes on or within the lens and visual acuity and refractive changes recorded. All cases were dilated at 3-5 weeks postoperatively to facilitate observation of changes. Representative slit lamp photos were taken. RESULTS: Deposits on the intraocular lens surface were noted on 18 of 41 lenses at 3-5 weeks post surgery. Deposits were not found on examinations conducted during the first postoperative week. All changes had fully resolved by 3 months. CONCLUSIONS: The changes recorded had no impact on visual acuity. The deposits noted do not represent clinically important pathology. They may be an unusual marker of biocompatibility with this lens. Surgeons using this lens should be aware of these changes. 相似文献
45.
Facial nerve paralysis or symptoms of audiovestibular nerve dysfunction may be the first indication of one of the group of bone diseases known as the osteopetroses. We describe three such patients. The pathophysiology of these diseases and the treatment of the resulting symptoms of facial and audiovestibular nerve dysfunction are discussed. 相似文献
46.
47.
Preoperative percutaneous transfemoral catheter embolization of feeding vessels in glomus jugulare tumors, followed by immediate application of standard surgical techniques, presents the treatment of choice, allowing meticulous microsurgery with virtually complete hemostasis. Therefore, the surgeon can operate in a bloodless environment throughout the compressed and intricate anatomic field, amidst such important yet vulnerable structures as cranial nerves, inner ear, carotid artery, jugular bulb, venous sinuses, and dura, while reducing surgical error and functional deficit for the patient. Review of the last 11 cases of glomus jugulare tumors at UCLA shows that even extensive Alford grade 2 tumors of the middle ear, jugular bulb, and mastoid had only minor blood losses with this combined technique of embolization-immediate surgery, as compared with earlier surgical methods. Pertinent literature on glomus jugulare and its treatment is reviewed. Combined embolization and immediate surgery offer the best approach for treatment of resectable glomus jugulare tumors. 相似文献
48.
Gonzales AJ; Christensen JG; Preston RJ; Goldsworthy TL; Tlsty TD; Fox TR 《Carcinogenesis》1998,19(7):1173-1183
49.
Identification of differentially expressed genes in aflatoxin B1- treated cultured primary rat hepatocytes and Fischer 344 rats 总被引:4,自引:1,他引:4
Harris AJ; Shaddock JG; Manjanatha MG; Lisenbey JA; Casciano DA 《Carcinogenesis》1998,19(8):1451-1458
Aflatoxin B1 (AFB1), a mutagen and hepatocarcinogen in rats and humans, is
a contaminant of the human food supply, particularly in parts of Africa and
Asia. AFB1-induced changes in gene expression may play a part in the
development of the toxic, immunosuppressive and carcinogenic properties of
this fungal metabolite. An understanding of the-role of AFB1 in modulating
gene regulation should provide insight regarding mechanisms of AFB1-induced
carcinogenesis. We used three PCR- based subtractive techniques to identify
AFB1-responsive genes in cultured primary rat hepatocyte RNA: differential
display PCR (DD-PCR), representational difference analysis (RDA) and
suppression subtractive hybridization (SSH). Each of the three techniques
identified AFB1- responsive genes, although no individual cDNA was isolated
by more than one technique. Nine cDNAs isolated using DD-PCR, RDA or SSH
were found to represent eight genes that are differentially expressed as a
result of AFB1 exposure. Genes whose mRNA levels were increased in cultured
primary rat hepatocytes after AFB1 treatment were corticosteroid binding
globulin (CBG), cytochrome P450 4F1 (CYP4F1), alpha-2 microglobulin,
C4b-binding protein (C4BP), serum amyloid A-2 and glutathione S-transferase
Yb2 (GST). Transferrin and a small CYP3A-like cDNA had reduced mRNA levels
after AFB1 exposure. Full-length CYP3A mRNA levels were increased. When
liver RNA from AFB1-treated male F344 rats was evaluated for transferrin,
CBG, GST, CYP3A and CYP4F1 expression, a decrease in transferrin mRNA and
an increase in CBG, GST, CYP3A and CYP4F1 mRNA levels was also seen.
Analysis of the potential function of these genes in maintaining cellular
homeostasis suggests that their differential expression could contribute to
the toxicity associated with AFB1 exposure.
相似文献
50.
Characterization of the insulin-like growth factor axis in a human hepatoma cell line (PLC) 总被引:4,自引:0,他引:4
Scharf JG; Schmidt-Sandte W; Pahernik SA; Ramadori G; Braulke T; Hartmann H 《Carcinogenesis》1998,19(12):2121-2128