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71.
The effect of 1-[β-[3-(4-methoxyphenyl)pro- poxy]-4-methoxyphenethyl]-1H-imidazole hydrochloride (SKF 96365) on Ca2+ signaling in Madin Darby canine kidney (MDCK) cells was examined. SKF 96365 at 25–100 μM evoked a robust [Ca2+]i transient in a dose-dependent manner, measured by fura-2 fluorimetry. A concentration of 10 μM SKF 96365 did not have an effect. The transient consisted of a slow rise, a gradual decay, and a sustained plateau in physiological Ca2+ medium. Removal of extracellular Ca2+ reduced the Ca2+ signals evoked by 50–100 μM SKF 96365 by nearly half in the area under the curve, suggesting that SKF 96365 induced intracellular Ca2+ release and also extracellular Ca2+ influx. A concentration of 100 μM SKF 96365 caused significant Mn2+ quench of fura-2 fluorescence, which was partly inhibited by La3+ (1 mM) or Gd3+ (0.1 mM), indicating that the SKF 96365-induced Ca2+ influx had two components: one is sensitive to La3+ (1 mM) or Gd3+ (0.1 mM), the other is not. The internal Ca2+ source for the SKF 96365-induced [Ca2+]i transient was the endoplasmic reticulum Ca2+ store because, pretreatment with thapsigargin and cyclopiazonic acid, two inhibitors of the endoplasmic reticulum Ca2+ pump nearly abolished the SKF 96365-induced [Ca2+]i increase in Ca2+-free medium. In contrast, pretreatment with 100 μM SKF 96365 only partly depleted the thapsigargin-sensitive Ca2+ store. Addition of 10 mM Ca2+ induced a significant [Ca2+]i increase after prior incubation with 100 μM SKF 96365 in Ca2+-free medium, demonstrating that SKF 96365 induced capacitative Ca2+ entry. This capacitative Ca2+ entry was about 40% of that induced by 1 μM thapsigargin. Additional to inducing its own capacitative Ca2+ entry, 100 μM SKF 96365 partly inhibited thapsigargin- or uridine trisphos-phate (UTP)-induced capacitative Ca2+ entry. We also investigated the mechanisms underlying the decay of the SKF 96365-induced [Ca2+]i transient. Inhibition of the plasma membrane Ca2+ pump with La3+ or Gd3+, or lowering extracellular Na+ level to 0.35 mM, significantly increased the SKF 96365-induced [Ca2+]i transient. In contrast, the mitochondrial uncoupler carbonylcyanide m-chlorophenylhydrazone had little effect. In Ca2+-free medium, the thapsigargin-induced [Ca2+]i increase was greatly reduced by pretreatment with SKF 96365. Collectively, we have found that besides its well-known inhibitory action on capacitative Ca2+ entry in many cell types, in MDCK cells SKF 96365 exerted multiple and complex effects on Ca2+ signaling. It induced a considerable increase in [Ca2+]i by releasing Ca2+ from the endoplasmic reticulum store followed by capacitative Ca2+ entry. It also caused a direct Ca2+ entry. The decay of the SKF 96365 response was significantly governed by efflux via the plasma membrane Ca2+ pump or Na+/Ca2+ exchange. Sequestration by mitochondria or the endoplasmic reticulum played a minor role. We caution use of SKF 96365 as an inhibitor of capacitative Ca2+ entry. Received: 21 September 1998 / Accepted: 2 December 1998  相似文献   
72.
Rates of prostate cancer (PCa) have increased so dramatically over the last decade that the age adjusted incidence rate for PCa is now greater than that any other cancer among men in the United States. This review, published as a three part series, provides a state-of-art assessment of the PCa problem in its divergent aspects.Part 1 covers epidemiology, incidence and progression. Several epidemiological studies have demostrated that first degree male relatives of men with PCa are at increased risk of developing the disease. Familial and genetic factors as well as medical, anthropometric, dietary, hormonal and occupational factors involved in PCa are discussed. Postmortem examination of the prostate in men without evidence of PCa documented a high frequency of adenocarcinoma. Latent disease occurred as early as the second decade of life. Although there is no significant difference in incidence between Caucasian and African-American males, high grade prostatic intraepithelial neoplasia (HGPIN) is higher in the latter group. While dietary fat, androgens and certain environmental factors may be determinants for PCa, the exact mechanism of tumorigenesis is still relatively unknown. The current thinking of the role of genomic instability, chromosomal alterations, tumor suppressor genes and the androgen receptor are explored.  相似文献   
73.
An experimental analogue of a discount drink policy known as the happy hour was used to study the effects of purchase price on drinking behavior. Male volunteers with a prior history of either casual (N=20) or heavy (N=14) drinking were given free access to beverage alcohol during a 20-day period. Approximately half the subjects could purchase alcohol under a single-price condition (50 ¢/drink), while a matched group was given a price reduction daily (25 ¢/drink) during a three-hour period in the afternoon. The results demonstrated that the afternoon price reduction significantly increased alcohol consumption in both casual and heavy drinkers. Reinstatement of the standard purchase price effectively suppressed drinking in both groups. The findings are discussed in terms of the theoretical and research implications of environmental influences on drinking.  相似文献   
74.
Summary The electromyographic (EMG) activities of suprahyoideal muscle were recorded to measure naloxone-precipitated abstinence signs in morphine-dependent rats anesthetized with urethane (1 g/kg). Rats were rendered dependent on morphine by implanting 2 morphine pellets (75 mg each) and abstinence signs were induced by intravenous injections of various doses of naloxone at different times after pellet implantation. Three precipitated abstinence signs, a) myoclonic twitch activity (MTA), b) mastication, and c) body shakes were observed on EMG recordings after the injection of naloxone. Of these symptoms, only the MTA induced by naloxone (10 g/kg) occurred 4 h after pellet implantation and its sensitivity to naloxone increased with prolonged pellet implantation. Both mastication and precipitated shakes could be induced at 24 h. However, higher doses of naloxone were required to produce the shakes than is required to induce mastication. There appears to be a positive correlation between the intensity of naloxone-induced MTA and the degree of physical dependence on morphine. Since the MTA and mastication can be induced by low doses of naloxone in morphine-dependent rats, we suggest that these two parameters may be used to detect morphine abstinence signs in this species.Deceased February 13, 1979  相似文献   
75.
While it is known that chamomile contains matricine, so far it was not clear whether this chamazulene precursor is as pharmacologically active as chamazulene itself. As guajazulene, moreover, is frequently used instead of matricine and chamazulene in chamomile preparations it was the purpose of this work to compare the antiphiogistic activities of all these substances. The antiphiogistic properties after oral administration of chamazulene and matricine in comparison with guajazulene, (-)-alpha-bisabolol (INN Levomenol) and salicylamide were studied in rat paw carrageenin edema. Two and three hours after administration of the substances, matricine on a molar basis was similarly effective as (-)-alpha-bisabolol. Four hours after administration, no significant differences were found between the two substances. On the other hand, chamazulene und guaj azulene showed significantly less activity than (-)-alpha-bisabolol and matricine. After four hours, the pharmacological effects of guaj azulene decreased significantly whereas chamazulene showed nearly constant activities over the entire testing period. Guajazulene thus proves to have a therapeutic performance of shorter terms than chamazulene. The results prove that matricine, chamazulene and guajazulene must be considered as having different antiphiogistic activities and that these substances cannot be replaced by each other arbitrarily in chamomile preparations.  相似文献   
76.
To investigate the relationship between "systemic" antitumor immunity and "local" antitumor immunity with respect to the histopathological stage of gastric cancer, interleukin-2 stimulated mixed lymphocyte tumor extract reactions (ILS-MLTR) of peripheral blood lymphocytes (PBL) and regional node lymphocytes (RNL) were evaluated in 59 gastric cancer patients. ILS-MLTRs of both PBL and RNL decreased with the advance of cancer stage, but ILS-MLTRs of PBL were always lower than those of RNL. Positive correlations in MLTR between PBL and RNL were found in patients with depth of invasion to muscularis propria and serosa and peritoneal dissemination. Inverse correlations between PBL and RNL were noted in patients with stage IV and distant nodal involvement. These results suggest that variations in the anticancer immunities might be effectively managed by an immunotherapy which is designed according to the responsiveness in the immune parameter ILS-MLTR.  相似文献   
77.
The sonographic and computed tomographic (CT) findings were reviewed in 17 patients with acute acalculous cholecystitis (AAC) over a 6-year period from 1984 to 1989. Of the six patients in whom both ultrasound and CT were performed, CT revealed marked gallbladder (GB) wall abnormalities, including perforation, and pericholecystic fluid collections in five patients not demonstrated by sonography. Of the total group, five patients had GB wall thicknesses of 3 mm (normal) at pathologic examination, which demonstrated a spectrum of disease ranging from acute hemorrhagic/necrotizing, to gangrenous acalculous cholecystitis with perforation. Sonography was falsely negative or significantly underestimated the severity of AAC in seven of the 13 patients examined by sonography. CT because of its superior ability to assess pericholecystic inflammation may provide additional diagnostic information even after a thorough sonographic study in cases of AAC.  相似文献   
78.
Twenty-seven persons who had undergone jejunoileal bypass surgery eight months or more previously returned a questionnaire which sought information about: (a) Demographic characteristics and weight loss; (b) pre- and postoperative eating behavior and food selection; (c) dietary instruction; (d) postoperative complications; and (e) postoperative attitudes. Twenty other patients were seen in a surgery clinic and interviewed informally to aid in the evaluation of data. Neither demographic characteristics nor weight loss correlated with other variables, including food selection, behavior, attitudes, or complications. Postoperative complications did relate to the consumption of green vegetables and "snacking." Postoperative changes noted were diminished appetite and less use of alcoholic beverages. Changes in post-operative eating behavior were positively correlated with changes in patients' attitudes of self-confidence and self-esteem. Neither a dietitian nor a nutritionist had been available on a structured consultation basis. During the interviews, subjects did express a desire for dietary discussions with trained professionals. In spite of distress and complications, most subjects were satisfied with the operation and perceived an improvement in their lives.  相似文献   
79.
Objective: The symptoms of depression experienced by women during the postnatal period may have profound effects on the lifelong health of both the mother and the child. In this randomized controlled study, we systematically evaluated the effects of weekly supportive group meetings for women with postnatal distress. Methods: Sixty postnatally distressed women were randomly assigned to support (n=30) and control (n=30) groups. Women assigned to the support group participated in four supportive group sessions that comprised discussions concerning transition to motherhood, postnatal stress management, communication skills, and life planning. Results: Subjects who attended the support sessions had significantly decreased scores on the Beck Depression Inventory (BDI) and the Perceived Stress Scale (PSS), and significantly increased scores on the Interpersonal Support Evaluation List (ISEL) as evaluated at the end of the fourth weekly session. In contrast, no significant changes were observed in the control group during this period. Conclusion: This is the first controlled study to provide evidence that participation in support groups for postnatally distressed women provides quantifiable psychosocial benefits.  相似文献   
80.
The spatial memory of a single patient (YR) was investigated. This patient, who had relatively selective bilateral hippocampal damage, showed the pattern of impaired recall but preserved item recognition on standardised memory tests that has been suggested by Aggleton and Shaw [Aggleton JP, Shaw C. Amnesia and recognition memory: a reanalysis of psychometric data. Neuropsychologia 1996;34:51-62] to be a consequence of Papez circuit lesions. YR was tested on three recall tests and one recognition test for visuospatial information. The initial recall test assessed visuospatial memory over very short unfilled delays and YR was not significantly impaired. This test was then modified to test recall of allocentric and egocentric spatial information separately after filled delays of between 5 and 60 s. YR was found to be more impaired at recalling allocentric than egocentric information after a 60 s interval with a tendency for the impairment to increase up to this delay. Recognition of allocentric spatial information was also assessed after delays of 5 and 60 s. YR was impaired after the 60 s delay. The results suggest that the human hippocampus has a greater involvement in allocentric than egocentric spatial memory, and that this most likely concerns the consolidation of allocentric information into long-term memory rather than the initial encoding of allocentric spatial information. The findings also suggest that YR's item recognition/free recall deficit pattern reflects a problem retrieving or storing certain kinds of associative information.  相似文献   
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