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41.
The incidence of disturbed sleep is strongly increased in healthy and demented elderly. Age-related alterations in the circadian timing system appear to contribute strongly to these problems. With increasing age, a lack of input to the suprachiasmatic nucleus (SCN), the biological clock of the brain, may accelerate de-activation of neurons involved in the generation of 24-h rhythm or output of this rhythm. This process appears to be reversible, since supplementation of stimuli that impinge on the SCN can re-activate these neurons and ameliorate disturbances in the sleep–wake rhythm.  相似文献   
42.
Mann  LC; Hawes  DR; Ghods  M; Bednar  EJ; Potchen  EJ 《Radiology》1987,164(1):121-122
Data obtained on 426 consecutive patients referred to a breast center by 122 physicians, including family practitioners, general surgeons, and other specialists, showed that the obstetricians-gynecologists referred the greatest average number of patients per physician, with more than 50% of these referrals for screening mammography. Internists referred fewer patients by nearly a factor of ten, with only one-third of these patients referred for screening mammography. Internists may be the weakest link in the utilization of screening mammography.  相似文献   
43.
44.
EJ Lee  ; CA Schiffer 《Transfusion》1989,29(5):384-389
Sixty consecutive patients with untreated acute leukemia alternately received either ABO-matched or ABO-mismatched random-donor platelet transfusions prepared from pooled platelet concentrate stored for 1 to 3 days. Patients were assigned randomly to receive matched or mismatched platelets as their first transfusion, and the first four transfusions were analyzed. In 40 evaluable patients, there was no significant difference (paired t test) between the 10-minute posttransfusion corrected count increments (CCI) of the initial transfusions of matched and mismatched platelets. In contrast, the second matched transfusion was significantly better than the second mismatched transfusion. This effect of ABO compatibility was particularly pronounced in a subset of patients. Six patients in whom mismatched transfusions were consistently inferior to matched transfusions had either a significant increase in anti-A or -B isoagglutinin titers following the first transfusion or elevated titers before or at the conclusion of the study. Conversely, in five patients in whom there was no apparent effect of ABO mismatching, only one had an increase in isoagglutinin titer. Platelet survival was not altered as the ratio of 18-hour to 10-minute posttransfusion CCl was 0.6 for both matched and mismatched platelet transfusions. These data demonstrate that ABO compatibility can affect the results of random-donor platelet transfusions and that patients who experience poor increments from ABO-mismatched platelets may benefit from a trial of ABO-compatible platelets before the initiation of HLA-matched platelet transfusion.  相似文献   
45.
The mechanism for consumption of terminal complement components and release of bound components from the surface of serum-resistant salmonella minnesota S218 was studied. Consumption of C8 and C9 by S218 occurred through interaction with C5b67 on the bacterial surface because C8 and C9 were consumed when added to S218 organisms previously incubated in C8-deficient serum and washed to remove all C5b67 on the bacterial surface because C8 and C9 were consumed when added to S218 organisms previously incubated in C8- deficient serum and washed to remove al but cell bound C5b67. Rapid release of (125)I C5 and (125)I C7 from the membrane of S218 was dependent on binding of C8 because (125)I C5 and (125)I C7 deposition in C8D serum was stable and was twofold higher in C8D than in PNHA, and addition of purified C8 or C8 and C9 to S218 previously incubated in C8D serum caused rapid release of (125)I C5 and (125)I C7 from the organism. Analysis by sucrose density gradient ultracentrifugation of the fluid phase from the reaction of S218 and 10 percent PNHS revealed a peak consistent with SC5b-9, in which the C9:C7 ratio was 3.3:1, but the NaDOC extracted bound C5b-9 complex sedimented as a broad peak with C9:C7 of less than 1.2:1. Progressive elution of C5b67 and C5b-9 from S218 but not serum-sensitive S. minnesota Re595 was observed with incubation in buffers of increasing ionic strength. Greater than 90 percent of the bound counts of (125)I C5 or (125)I C9 were released from S218 by incubation in 0.1 percent trypsin, but only 57 percent of (125)I C9 were released by treatment of Re595 with trypsin. These results are consistent with the concept that C5b-9 forms on the surface of the serum-sensitive S. minnesota S218 in normal human serum, but the formed complex is released and is not bactericidal for S218 because it fails to insert into hydrophobic outer membrane domains.  相似文献   
46.
47.
The purpose of this study was to 1) compare two commonly practiced stretching techniques to determine which is most effective for improving hip range of motion, and 2) evaluate the effect of these techniques on gait economy. Seven asymptomatic males, 18-22 years of age, served as subjects. Goniometric measurements of hip range of motion (ROM) and gait economy, as measured by submaximal oxygen consumption of walking and running on a treadmill, were taken before and after each of the two stretching procedures, (a) static stretching, and (b) soft tissue mobilization with proprioceptive neuromuscular facilitation (STM/PNF). Static stretching procedures resulted in significant improvements in ROM for hip extension (p < 0.01) and hip flexion (p < 0.01). The STM/PNF also resulted in significant improvements in hip extension ROM (p < 0.01) and hip flexion ROM (p < 0.05). There was a significant improvement in gait economy at 40% VO2max (p < 0.05), at 60% VO2max (p < 0.05), and at 80% VO2max (p < 0.01) following the static stretching procedure. The STM/PNF procedure improved gait economy only at one workload, 60% of VO2max (p < 0.05). These results suggest that a single bout of static stretching or STM/PNF was effective for improving hip ROM but static stretching was more effective for improving gait economy in young, asymptomatic males. J Orthop Sports Phys Ther 1989;10(9):350-357.  相似文献   
48.
The EDTNA/ERCA survey of the treatment of water for dialysis was the third project organised through the Collaborative Research Programme (CRP). Data was collected from 69 haemodialysis facilities in 14 countries. Water quality in European dialysis units was mainly self‐regulated. The majority of centres aimed to meet the requirements of the European Pharmacopoeia, but only 50% carried out tests to check compliance. All facilities used reverse osmosis to treat water for dialysis, most also used softening and carbon adsorption. There was a wide variation in policies for the maintenance of carbon filters, and for the control and monitoring of contamination in the distribution system. Endotoxin tests carried out in 27 facilities showed that higher levels of contamination are associated with systems that are infrequently disinfected, and also with older system designs. The survey indicated that guidelines for water treatment are urgently needed. EDTNA/ERCA guidelines for microbiological monitoring are now being drafted, additional guidelines are under consideration.  相似文献   
49.

Background

The authors tested the hypothesis that depression is a possible factor influencing the course of cancer by reviewing prospective epidemiological studies and calculating summary relative risks.

Methods

Studies were identified by computerized searches of Medline, Embase and PsycINFO. as well as manual searches of reference lists of selected publications. Inclusion criteria were cohort design, population-based sample, structured measurement of depression and outcome of cancer known for depressed and non-depressed subjects

Results

Thirteen eligible studies were identified. Based on eight studies with complete crude data on overall cancer, our summary relative risk (95% confidence interval) was 1.19 (1.06–1.32). After adjustment for confounders we pooled a summary relative risk of 1.12 (0.99–1.26).No significant association was found between depression and subsequent breast cancer risk, based on seven heterogeneous studies, with or without adjustment for possible confounders. Subgroup analysis of studies with a follow-up of ten years or more, however, resulted in a statistically significant summary relative risk of 2.50 (1.06–5.91).No significant associations were found for lung, colon or prostate cancer.

Conclusion

This review suggests a tendency towards a small and marginally significant association between depression and subsequent overall cancer risk and towards a stronger increase of breast cancer risk emerging many years after a previous depression.
  相似文献   
50.
幽门螺杆菌感染处理的当前观念——MaastrichtⅢ共识报告   总被引:8,自引:0,他引:8  
名词缩写 欧洲幽门螺杆菌研究小组:European Helicobacter Study Group,EHSG 胃食管反流病:gastro-esophageal reflux disease,GERD  相似文献   
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