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BACKGROUND: A National Institutes of Health consensus conference concluded that a daily calcium intake of 1500 mg reduces the severity of osteoporosis. Because dairy products are the main natural source of dietary calcium, a diet providing 1500 mg Ca must contain large quantities of dairy products. However, it is widely believed that the lactose content of these products will not be tolerated by persons with lactose maldigestion (approximately 30% of the adult US population). OBJECTIVE: We evaluated the symptoms of lactose maldigestion and digestion when the diet was supplemented with dairy products providing 1300 mg Ca/d. DESIGN: Sixty-two women (31 with lactose maldigestion and 31 without) were studied in a double-blind, randomized protocol. Symptoms were compared during 1-wk periods when the diet was supplemented with 480 mL (2 cups) milk, 56 g cheese, and 240 mL yogurt provided as conventional products (34 g lactose/d) or as lactose-hydrolyzed products (2 g lactose/d). RESULTS: Women who digested lactose reported no significant difference in symptoms between the 2 treatment periods. Women with lactose maldigestion reported significantly increased flatus frequency and subjective impression of rectal gas during the period of high lactose intake; however, bloating, abdominal pain, diarrhea, and the global perception of overall symptom severity were not significantly different between the 2 treatment periods. CONCLUSION: The symptoms resulting from lactose maldigestion are not a major impediment to the ingestion of a dairy-rich diet supplying approximately 1500 mg Ca/d. 相似文献
74.
The purpose of this study was to examine the meaning of local control, especially on survival, in breast cancer patients treated by lumpectomy with or without radiotherapy. We analyzed the survival results of four major published randomized trials that compare conservation surgery with or without radiation using three different statistical approaches: p-values, confidence intervals, and Bayesian techniques. All four trials report statistically significant increased local control and improved survival for the irradiated patients. Survival based on p-values and confidence intervals shows statistical significance for long-term follow-up of the NSABP-B06 trial, but not for the other trials, probably because of small sample sizes and short follow-up. At 10 years, the overall survival rates for the NSABP-B06 were 65% and 71% for lumpectomy alone or with radiation respectively. Interpreted in a Bayesian framework, the expected advantage in 10-year survival was 6% (the mean of NSABP-B06 10-year survival) with an 83% probability that the 10-year survival difference may lie between 2% and 10%. An 85% probability that 3% of patients will survive at 10 years because of irradiation translates into a 30% reduction in annual odds of death several years after treatment in stage I good prognosis patients and 15% in stage I poor prognosis patients. Analysis of the randomized trials comparing lumpectomy with or without radiation indicate a clear improvement in survival for the irradiated patients associated with increased local control. Combination of improved survival with the reduced psychological and economic costs associated with local recurrence argues well for the inclusion of radiation for many breast cancer patients. 相似文献
75.
OBJECTIVE: To determine the relation of gas passage and abdominal bloating to the production of gas in the colon. DESIGN: Randomized, double-blind, crossover study of gaseous symptoms during a 1-week period. SETTING: A Veterans Affairs medical center. PARTICIPANTS: 25 healthy medical center employees. INTERVENTION: Participants' diets were supplemented with either a placebo (10 g of lactulose, a nonabsorbable sugar), psyllium (a fermentable fiber), or methylcellulose (a nonfermentable fiber). MEASUREMENTS: All participants were polled for gaseous symptoms (including number of gas passages, impression of increased rectal gas, and abdominal bloating), and five were examined for breath hydrogen excretion. RESULTS: Participants passed gas 10 +/- 5.0 times per day (mean +/- SD) during the placebo period. A significant increase in gas passages (to 19 +/- 12 times per day) and a subjective impression of increased rectal gas were reported with lactulose but not with either of the two fiber preparations. Breath hydrogen excretion, an indicator of hydrogen production in the colon, did not increase after ingestion of either of the fibers. However, a statistically significant (P < 0.05) increase in feelings of abdominal bloating (which the participants perceived as excessive gas in the bowel) was reported with both fiber preparations and with lactulose. CONCLUSIONS: The physician should distinguish between excessive gas (which indicates excessive gas production) and feelings of bloating (which are usually unrelated to excessive gas production). Treatment of the former consists of limiting the supply of fermentable material to the colonic bacteria. Symptoms of bloating usually indicate the irritable bowel syndrome, and therapy should be directed accordingly. 相似文献
76.
M Bialer A Yacobi D Moros B Levitt JM Houle MS Munsaka 《Canadian Metallurgical Quarterly》1998,39(5):513-519
Ocular surface mucin is secreted from both goblet cells in the conjunctival epithelium and corneal epithelial cells. To clarify its mechanism of secretion in corneal epithelial cells, a rat cornea organ culture system was used to evaluate the second messenger roles of cyclic-AMP (cAMP), cyclic-GMP (cGMP) and protein kinase C (PKC) in modulating mucin-like glycoprotein secretion. Rat cornea sections (3 mm diameter) were cultured in TC-199 medium, and radiolabeled with sodium sulfate for 18 hr. After washing, the corneas were treated with various second messenger modulating agents for 30 min. The culture media were reacted with Dolichos biflorus (DBA)-lectin, and mucin-like glycoprotein was isolated. Then the radioactivity of DBA-binding mucin-like glycoprotein was isolated. Then the radioactivity of DBA-binding mucin-like glycoprotein was measured. There was a time-dependent increase in mucin-like glycoprotein was measured. There was a time-dependent increase in mucin-like glycoprotein secretion, whereas after corneal epithelial debridement the secretion was markedly inhibited by 81%. Mucin-like glycoprotein secretion was stimulated in a dose-dependent manner following elevation of cAMP levels by exposure to either forskolin, dibutyryl cAMP or 3-isobutyl-1-methylxanthine. Concomitant exposure to the cAMP dependent protein kinase inhibitor, KT5720 completely inhibited their stimulatory effects. Neither exposure to dibutyryl cGMP nor nitroprusside affected mucin-like glycoprotein secretion. Stimulation by PKC, phorbol 12, 13-dibutyrate (PDBu) also increased mucin-like glycoprotein secretion in a dose-dependent fashion. The PKC inhibitor, calphostin C completely inhibited the stimulation by PDBu of mucine-like glycoprotein secretion. These results demonstrate that corneal epithelial cells secrete mucin-like glycoprotein, which is mediated by cAMP and PKC signal transduction pathways. 相似文献
77.
Comments on L. C. Buffardi and J. A. Nichols's (1981) list of rejection rates for psychological journals and further examines the relation between rejection rates, citation impact, and journal value. It was found that 69% of the variance in rejection rates was explained by area and type of journal. As Buffardi and Nichols reported, rejection rates were higher for APA than for non-APA journals (80.27% vs 65.37%), and citation indices were higher for APA than for non-APA journals (2.63 vs 0.91). Further results suggest that experimental journals have a higher Social Sciences Citation Indices impact than do general journals. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
Reports an error in the original article by J. Rotton et al (American Psychologist, 1993[Aug], Vol 48[8], 911–912). Table 1 listed the journal Psychological Research twice, and the journals Cognition and Child Study Journal were omitted. The mean SSCI for applied journals in Table 1 should have been 1.17. Multiple rather than squared multiple correlations were reported for rejection rates. Area and type of journal explained 48% of variance in rejection rates, and the F ratio for predicting citations should have been F(9,28)?=?14.82. On page 912, the mean SSCI for experimental journals should have been 1.51. (The following abstract of this article originally appeared in record 1994-03368-001.) Comments on L. C. Buffardi and J. A. Nichols's (1981) list of rejection rates for psychological journals and further examines the relation between rejection rates, citation impact, and journal value. It was found that 69% of the variance in rejection rates was explained by area and type of journal. As Buffardi and Nichols reported, rejection rates were higher for APA than for non-APA journals (80.27% vs 65.37%), and citation indices were higher for APA than for non-APA journals (2.63 vs 0.91)… (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
79.
SN Bykovskaja MJ Buffo M Bunker H Zhang A Majors M Herbert A Lokshin ML Levitt A Jaja D Scalise D Kosiban C Evans S Marks J Shogan 《Canadian Metallurgical Quarterly》1998,63(5):620-630
Fiducial markers are reference points used in the registration of image space(s) with physical (patient) space. As applied to interactive, image-guided surgery, the registration of image space with physical space allows the current location of a surgical tool to be indicated on a computer display of patient-specific preoperative images. This intrasurgical guidance information is particularly valuable in surgery within the brain, where visual feedback is limited. The accuracy of the mapping between physical and image space depends upon the accuracy with which the fiducial markers were located in each coordinate system. To effect accurate space registration for interactive, image-guided neurosurgery, the use of permanent fiducial markers implanted into the surface of the skull is proposed in this paper. These small cylindrical markers are composed of materials that make them visible in the image sets. The challenge lies in locating the subcutaneous markers in physical space. This paper presents an ultrasonic technique for transcutaneously detecting the location of these markers. The technique incorporates an algorithm based on detection of characteristic properties of the reflected A-mode ultrasonic waveform. The results demonstrate that ultrasound is an appropriate technique for accurate transcutaneous marker localization. The companion paper to this article describes an automatic, enhanced implementation of the marker-localization theory described in this article. 相似文献
80.
Network intrusion detection 总被引:3,自引:0,他引:3
Intrusion detection is a new, retrofit approach for providing a sense of security in existing computers and data networks, while allowing them to operate in their current "open" mode. The goal of intrusion detection is to identify unauthorized use, misuse, and abuse of computer systems by both system insiders and external penetrators. The intrusion detection problem is becoming a challenging task due to the proliferation of heterogeneous computer networks since the increased connectivity of computer systems gives greater access to outsiders and makes it easier for intruders to avoid identification. Intrusion detection systems (IDSs) are based on the beliefs that an intruder's behavior will be noticeably different from that of a legitimate user and that many unauthorized actions are detectable. Typically, IDSs employ statistical anomaly and rulebased misuse models in order to detect intrusions. A number of prototype IDSs have been developed at several institutions, and some of them have also been deployed on an experimental basis in operational systems. In the present paper, several host-based and network-based IDSs are surveyed, and the characteristics of the corresponding systems are identified. The host-based systems employ the host operating system's audit trails as the main source of input to detect intrusive activity, while most of the network-based IDSs build their detection mechanism on monitored network traffic, and some employ host audit trails as well. An outline of a statistical anomaly detection algorithm employed in a typical IDS is also included 相似文献