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排序方式: 共有7021条查询结果,搜索用时 14 毫秒
1.
Decreases in sex hormone levels with menopause may bring about a number of consequences in women's general health and sexual well-being, especially when levels decline suddenly and prematurely, as in surgical menopause. In addition to the well-established role of estrogens in preserving the biological basis of sexual response, there is emerging evidence that androgens are significant independent determinants affecting sexual desire, activity and satisfaction, as well as mood, energy and other components of women's health. Hypoactive sexual desire disorder (HSDD), a persistent absence of sexual fantasies or thoughts and/or desire for and receptivity to sexual activity that causes personal distress, is experienced by some postmenopausal women. Even though conventional hormone therapy with estrogens or estrogens and progestogens may be effective for vaginal atrophy, increasing vaginal lubrication and reducing dyspareunia, it has not been shown to consistently increase sexual desire or activity and many women with sexual dysfunction remain unresponsive. Several recent, large, phase III studies have shown that the addition of transdermal testosterone to conventional hormone therapy can be helpful in surgically menopausal women presenting with HSDD. After 24 weeks of treatment in these studies, testosterone-treated women experienced significantly greater increases in satisfying sexual activity and sexual desire, and greater decreases in distress, than placebo-treated women. Accurate clinical assessment and individualized management of sexual symptoms are fundamentally important for all menopausal women with HSDD or other sexual problems. 相似文献
2.
C Schmitt J Brachmann W Saggau T Beyer B Waldecker K Scharowski T Hilbel M Montero B Offner W Sch?ls 《Zeitschrift für Kardiologie》1991,80(11):665-672
In 41 patients with recurrent sustained ventricular tachycardia and/or ventricular fibrillation an integrated pacemaker-defibrillator-system (PCD, Medtronic, model 7216 A or 7217 B) was implanted. In 21 out of 24 (88%) patients a new transvenous implantation technique in combination with a subcutaneous patch electrode was used. The implanted devices comprise antibradycardiac pacemaker functions, two different forms of antitachycardiac pacemaker functions (ramp and burst pacing), and internal cardioversion or defibrillation capabilities. During a mean follow-up of 8 months 147 episodes of ventricular tachycardia were detected, 131 of them were terminated successfully by antitachycardiac pacing; in 13 episodes internal cardioversion was applied to revert ventricular tachycardia. Twenty-seven episodes of ventricular fibrillation or rapid ventricular tachycardia (greater than 200/min) were detected and successfully terminated by internal defibrillation. In six patients with intermittent rapid atrial fibrillation, change of antiarrhythmic therapy was required to avoid activation of the device. The new integrated pacemaker-defibrillator systems improve therapy in patients with life-threatening tachyarrhythmias by reducing the number of internal cardioversions/defibrillations; the non-thoracotomy approach reduces the post operative risk. 相似文献
3.
J. Viac C. Goujon L. Misery V. Staniek M. Faure D. Schmitt A. Claudy 《Photodermatology, photoimmunology & photomedicine》1997,13(3):103-108
Ultraviolet radiation B (UVB) on the skin induces erythema, inflammation and modifications of the immune system. These changes have been reported after excessive short-term or long-term exposure to broad spectrum UVB. In this study, we examined the effects of local repetitive UVB irradiation of 311 nm wavelength on the skin of seven young volunteers. Skin biopsies were taken before and after UVB irradiation, and we immunohistochemically analyzed the expression of CD1a and HLA-DR antigens of Langerhans cells (LC), the possible infiltration of dermis/epidermis by CD11b macrophages, the modifications or the induction of intercellular adhesion molecule-1 (ICAM-1), E-selectin and vascular cell adhesion molecule-1 (VCAM-1) involved in the binding of leukocytes to the endothelial surface and the development of perivascular infiltrates of LFA-1+ mononuclear cells. We also determined the expression of substance P receptors (SPR) using biotinylated substance P (SPB). Exposure of UVB 311 nm induced a drastic reduction of CD1a+ cells and a moderate increase of HLA-DR+ dendritic cells in the epidermis without infiltration by CD11b macrophages. An increase of the binding of SPB to upper layer epidermal cells was noted in five of seven biopsies. In the dermis, vessel-associated ICAM-1 expression increased and an induction of E-selectin occurred on nearly 20 to 40% of endothelial cells, but VCAM-1 expression remained undetectable. The percentage of LFA-1+ cells did not change significantly after irradiation. These observations may be compatible with a selective role of UVB 311 nm on the skin immune response. 相似文献
4.
A survey of pediatricians in private practice in the Denver and Baltimore metropolitan areas was conducted to assess pediatricians' satisfaction with the telephone in their practices. The response rates were 84% (89/106) in Denver and 72% (90/125) in Baltimore. In both cities, 42% of the physicians were dissatisfied with their telephone systems. Dissatisfied physicians were less likely to provide a morning telephone hour (P less than .02), less likely to delegate calls to office staff (P less than .01), more likely to believe that they lacked sufficient time to handle daytime calls (P less than .0001), and more likely to be in group rather than solo practice (P less than .05). Younger age of the respondent approached, but did not reach, statistical significance in its association with dissatisfaction. 相似文献
5.
Economic efficiency versus social equality? The U.S. liberal model versus the European social model.
This article begins by challenging the widely held view in neoliberal discourse that there is a necessary trade-off between higher efficiency and lower reduction of inequalities: the article empirically shows that the liberal, U.S. model has been less efficient economically (slower economic growth, higher unemployment) than the social model in existence in the European Union and in the majority of its member states. Based on the data presented, the authors criticize the adoption of features of the liberal model (such as deregulation of their labor markets, reduction of public social expenditures) by some European governments. The second section analyzes the causes for the slowdown of economic growth and the increase of unemployment in the European Union--that is, the application of monetarist and neoliberal policies in the institutional frame of the European Union, including the Stability Pact, the objectives and modus operandi of the European Central Bank, and the very limited resources available to the European Commission for stimulating and distributive functions. The third section details the reasons for these developments, including (besides historical considerations) the enormous influence of financial capital in the E.U. institutions and the very limited democracy. Proposals for change are included. 相似文献
6.
PTH has diverse effects on bone metabolism: anabolic when given intermittently, catabolic when given continuously. The cellular
mechanisms underlying the varying target cell response are not clear yet. PTH induces RGS-2, a member of the Regulator of
G-protein Signaling protein family, via cAMP/PKA, and inactivates PKC-mediated signaling. To investigate intracellular signaling
pathways with different PTH concentration-time patterns, we treated UMR 106-01 osteoblast-like cells in a perfusion system.
PTH was administered intermittently (4 min/h, 10−7 M) or continuously at an equivalent cumulative dose (6.6 × 10−9 M). cAMP was measured using radioimmunoassay, mRNA levels using real-time rtPCR and ribonuclease protection assay, and protein
levels using Western immunoblotting. A single PTH pulse transiently increased cAMP levels by 2000% ± 1200%. In contrast to
continuous PTH exposure, cAMP induction remained unchanged with intermittent PTH, ruling out desensitization of the PTH receptor.
In continuously perfused cells, RGS-2 abundance was three to five times higher than in cells intermittently exposed to PTH
for up to 12 h. MKP-1 and -3 were significantly less induced with pulsatile PTH; exposure-mode-dependent differences in MMP-13
and IGFBP-5 were small. Pulsatile but not continuous PTH administration prevents PTHrP receptor desensitization and accumulation
of RGS-2 in osteoblasts, which should preserve PKC-dependent signaling. 相似文献
7.
8.
G R Seabrook D Karp D D Schmitt D F Bandyk J B Towne 《American journal of surgery》1990,160(5):501-505
Lifetime anticoagulation has become a therapeutic option for surgical patients with hypercoagulable states or prosthetic arterial bypass grafts. However, physicians may not achieve optimal anticoagulation or may attempt to limit the length of the therapy period because of the perceived morbidity from hemorrhagic complications of Coumadin therapy. A protocol for anticoagulant therapy monitored and regulated by a vascular nurse-clinician was reviewed. Coumadin was prescribed for 1,891 patient-months to 93 patients to maintain their prothrombin time 1.5 to 2 times control (range: 18 to 24 seconds). The mean (+/- SD) prothrombin time for the study population was 19.8 +/- 1.8 seconds. During follow-up, 472 (14%) of 3,479 prothrombin times measured were below the therapeutic range (n = 232) or prolonged (n = 240), prompting an adjustment in the Coumadin dose in 82 (88%) patients. Four patients developed recurrent vascular graft thrombosis while receiving anticoagulation. There were 6 major and 11 minor hemorrhagic complications. Patients with a chronic risk for arterial or venous thrombosis can have out-patient anticoagulant therapy administered at optimal intensity and regulated safely with a low incidence of hemorrhagic and thrombotic events. 相似文献
9.
Zusammenfassung Halbstrukturierte Inteviews mit 248 (ehemaligen) jüdischen Emigranten und Lagerh?ftlingen in Deutschland und drei Ziell?ndern
der jüdischen Emigration zeigen, da? Erinnerungen an traumatische Erlebnisse im Nationalsozialismus in zahlreichen allt?glichen
Kontexten auftreten und von zentraler Bedeutung für die Wahrnehmung der pers?nlichen Lebenssituation im Alter sind. Auf der
Grundlage der Ergebnisse einer Pilotstudie zur Frage nach der subjektiven Gliederung des Lebenslaufs bei (ehemaligen) jüdischen
Emigranten und Lagerh?ftlingen werden unterschiedliche Abschnitte der pers?nlichen Entwicklung nach dem Holocaust unterschieden.
Selbsteinsch?tzungen der Untersuchungsteilnehmer zur Intensit?t von Erinnerungen an traumatische Erlebnisse in diesen Entwicklungsabschnitten
unterstützen die Annahme, da? belastende Erinnerungen im Alter deutlich zugenommen haben. Die Untersuchungsteilnehmer unterscheiden
sich erheblich in den Formen der Auseinandersetzung mit solchen Erinnerungen. Einige Untersuchungsteilnehmer reagierten mit
Depressionen, Angstzust?nden, Gefühlen von überlebensschuld und Rückzug aus sozialen Beziehungen. Andere engagierten sich
hingegen in hohem Ma?e in sozialen Beziehungen, vor allem zu Angeh?rigen der jüngeren Generation, um dadurch zur Vermeidung
von Diskriminierung, Rassismus und Fremdenfeindlichkeit beizutragen.
Eingegangen: 14. August 1997, Akzeptiert: 26. Januar 1998 相似文献
10.
Development of cytochrome P-450-altered preneoplastic and neoplastic lesions during nitrosamine-induced hepatocarcinogenesis in the rat 总被引:3,自引:0,他引:3
The expression of four cytochrome (cyt.) P-450 isoenzymes has been studied in preneoplastic and neoplastic lesions during the course of nitrosamine-induced hepatocarcinogenesis in the female Wistar rat. Following exposure to diethylnitrosamine (50 or 100 ppm in the drinking water) for 10 days, animals were taken sequentially, and the livers were analyzed for the evolution of adenosine triphosphatase deficient focal lesions. These lesions were subdivided into different phenotypes with regard to their cyt. P-450 isoenzyme expression using serial frozen sections. Our results demonstrate that about 40% of the adenosine triphosphatase-deficient lesions show concomitant alterations in their cyt. P-450 isoenzyme contents. Of these lesions, islets which are characterized by decreased levels of at least three cyt. P-450 isoenzymes show a dramatic increase in their volumetric fraction of liver tissue with progression of time. Although only very few lesions express this phenotype, the contribution to the volumetric fraction of islet tissue raises from about 2% at 10 weeks to about 60% at 35 weeks after cessation of diethylnitrosamine treatment. By contrast, lesions which express less than two alterations in cyt. P-450 isoenzyme levels develop relatively slowly. Similar results were obtained when animals were exposed continuously to diethylnitrosamine for a period of up to 8 weeks. Following treatment of islet-bearing animals with phenobarbital, an induction of cyt. P-450 isoenzymes and NADPH-cyt. P-450-reductase was observed within preneoplastic and neoplastic lesions. This induction was most pronounced in large, expansively growing nodules, a type of lesion which displayed decreased levels of these enzymes in livers of animals not treated with phenobarbital. The elevation of the cyt. P-450 isoenzymes disappeared within 2 to 3 weeks after cessation of inducer treatment. Our results indicate that a high proportion of rapidly growing lesions has assumed a constitutive deficiency in cyt. P-450 isoenzyme expression during nitrosamine-induced hepatocarcinogenesis. This deficiency, however, is not an irreversible quality, since individual cyt. P-450 isoenzymes can be markedly induced by treatment with an enzyme inducer like phenobarbital. Thus, the observed decrease in cyt. P-450 expression during development of malignancy does not result from alterations in the cyt. P-450 encoding structural genes but may rather be related to abnormalities in the function of regulatory systems of a higher order which may play a central role in the maintenance of cell homeostasis. 相似文献