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1.
The role of caffeine or coffee in causing or promoting the incidence of serious disease is equivocal. Two design factors may account for the discrepancies in reported findings on the effects of coffee drinking: (a) imprecision of measurement and (b) confounding variables. A study of 2,714 white U.S. adults disclosed that, of 32 risk factors analyzed by linear and logistic regression, only sex and cigarette smoking were found to be important potential confounders of caffeine and coffee intake. Partial R2 values of the other 30 risk factors were relatively small and were inconsistent for each sex. It is unlikely that any of these factors could explain any of the reported associations between caffeine or coffee consumption and certain diseases. However, certain weak associations with caffeine or coffee intake should be included in the study design when they are known to be risk factors of a disease under investigation. These factors for men are dietary fat intake, vitamin C intake, and body mass index; and for women are vitamin use, alcohol intake, stress, and perceived health status.  相似文献   
2.
Ruggieri  PM; Laub  GA; Masaryk  TJ; Modic  MT 《Radiology》1989,171(3):785-791
The technique and feasibility of magnetic resonance (MR) angiography of intracranial vessels were studied in 35 healthy volunteers. Variations in image orientation, repetition time (TR), and flip angle were evaluated to determine their effects on flow-related enhancement. Gradient modifications--including echo time (TE), motion compensation, bandwidth, and field of view--were also studied in an effort to reduce motion-induced phase shifts. Results indicated that a FISP (fast imaging with steady precession) sequence with a TR of 50 msec, TE of 15 msec, velocity compensation in the read and section-select directions, acceleration compensation in the read direction, anisotropic volume, and a 1.25-mm partition thickness produced three-dimensional angiographic MR images that were accurate and reproducible in the depiction of the major intracranial vessels. Difficulties with field of view, persistent signal void secondary to higher-order motion, and spatial resolution remain major problems requiring additional study.  相似文献   
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BACKGROUND: In general practice, acute sinusitis is frequently diagnosed and treated with antibiotics. OBJECTIVE: This study aimed to determine the evidence for the effectiveness of antibiotic treatment in acute maxillary sinusitis in adults by assessing the methodological quality of placebo-controlled double-blind randomized trials. METHOD: An evaluation by four raters through a 35-item scoring-scale for internal and external validity of all placebo-controlled double-blind randomized trials on acute sinusitis found between January 1966 and July 1996. RESULTS: Eighty-five trials were excluded because they were not placebo-controlled, double-blind, randomized, or were carried out in patients with chronic sinusitis or in children. The three remaining trials were performed in different populations (one in general practice) between 1973 and 1978. Only one study claimed superiority of antibiotic treatment. Different inclusion criteria and major outcome measures were used by the authors. The reliability of major outcome events was reported poorly or not at all and in two studies outcome measures were clinically inappropriate. The studies scored 30-62% of the maximum attainable score for internal validity and 10-20% for external validity. CONCLUSION: The effectiveness of antibiotic treatment in acute maxillary sinusitis in a general practice population is not based sufficiently on evidence.   相似文献   
4.
Background: Research on religion and health suggests general health benefits for those who are more religiously involved. Particular aspects of religiosity that may influence this finding, however, have not been sufficiently investigated.Purpose: This study was designed to explore the relationship between religious orientation (intrinsic, extrinsic) and blood pressure reactivity among older (over 60 years) and younger (18–24 years) adults exposed to two qualitatively different laboratory stressors (cognitive, interpersonal).Methods:Participants were categorized as exhibiting either a predominately intrinsic or extrinsic religious orientation based on scores on the Religious Orientation Scale. They were subsequently exposed (in counterbalanced order) to two laboratory stressors that varied in terms of whether an interpersonal confrontation was involved. Measures of blood pressure were obtained at baseline and during stressor presentation.Results: Analyses indicated that older extrinsically religious individuals demonstrated exaggerated reactivity compared to younger participants and older intrinsically religious individuals. Older intrinsically religious participants did not differ from younger persons. Similar results were found for analysis of baseline data. Extrinsic participants had greater reactivity during the interpersonal confrontation condition than did intrinsic individuals.Conclusions: These findings suggest that religious orientation may be an important variable to study regarding cardiovascular reactivity in, particularly, older adults. This research was supported in part by National Institute on Aging Grant 1 R03 AG 18554-01. A previous version of this article was presented in August 2002 as a Citation Paper at the 110th Annual Convention of the American Psychological Association, Chicago. We thank Timothy W. Smith, James A. Blumenthal, Carl E. Thoresen, and Edward M. Heath for their assistance throughout this project. We also thank Llewellyn Jones and Jodi Hildabrandt for their efforts in collecting data.  相似文献   
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A 5-Year experience of 51 endoscopic transthoracic dorsal sympathectomies for idiopathic palmar hyperhidrosis in 26 patients is presented. Fifty-two percent complained of excessive sweating over their hands, 28% of axillary sweating and 20% over both areas, with a mean duration of 10 years. The second, third and fourth thoracic ganglia and their interconnecting fibres on the affected side were ablated using diathermy cautery. Over a mean follow up time of 26 months, this procedure was successful in curing or improving intractable sweating in 92%. However, axillary sweating was less well controlled than in the palms with 20% of patients describing residual wetness in the axilla. Compensatory sweating (75%) and gustatory sweating (48%) were the commonest side effects; despite this, most patients were satisfied with the functional and cosmetic outcome. Other complications included a temporary Horner's syndrome in one patient, a pneumothorax in the immediate post-operative period in another and a unilateral non-infective reactionary pleural effusion in a third. Two patients developed recurrence of palmar hyperhidrosis within 6 months of surgery. One has been successfully treated by re-operation on the affected side. All patients complained of mild to moderate interscapular chest pain which was easily controlled by non-steroidal anti-inflammatory agents, and resolved within 7–10 days post-operatively. The technique of endoscope transthoracic sympathectomy is effective, relatively simple to perform and usually requires only an overnight stay. It is recommended as the surgical treatment of choice for upper limb hyperhidrosis unresponsive to conservative measures.  相似文献   
7.
Co-existence of facial and occipital pain may occur in occipital neuralgia, migraine and cluster headache; suggesting convergence of trigeminal and cervical afferents. Such convergence has been shown in humans and other animals, but the site and extent of this are uncertain. In anaesthetized adult cats, the superior sagittal sinus and occipital nerve were stimulated electrically, and extracellular recordings made in the dorsolateral area of the upper cervical cord using glass-coated tungsten electrodes. Of 49 units in 10 cats, 33 (67%) had input from the superior sagittal sinus and the occipital nerve. Thirteen (27%) had superior sagittal sinus input and 3 (6%) had occipital nerve input. Convergent receptive fields were identified mechanically in 7 units. These experiments in cats show convergent input from occipital nerve and superior sagittal sinus on dorsolateral area units in two-thirds of cases studied. This experimental site of trigeminocervical convergence may relate to referral of pain in occipital neuralgia and other headaches.  相似文献   
8.
In patients with PG-dependent renal function, NSAID administration constantly reduces GFR and RBF in a dose-dependent fashion. In this situation, the risk of overt acute renal failure is high and should be taken into proper account. In contrast, the incidence of NSAID-related renal structural alterations appears to be very low, yet the absolute number of patients may be significant considering the wide use of such drugs. Concerning the antiproteinuric effect of NSAIDs, the unfavourable ratio risk/benefit does not seem to support their indication in proteinuric nephropathies. The development of PGHS-2 selective inhibitors is promising, and may open new therapeutical strategies in the treatment of the progression of renal disease.   相似文献   
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