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21.
Michael Phillips MRCP Preston Hensley PhD Richard A. Baiter MD Stanley L. Cohan MD 《Alcoholism, clinical and experimental research》1984,8(3):293-296
An improved method is described for the collection of breath for the subsequent assay of acetaldehyde and other volatile components. Breath is collected in a Pyrex gas-collecting tube sealed at both ends with Teflon taps. Prior to collection or assay of the samples, this tube is heated to 72 degrees C; breath is sampled for assay by piercing a rubber septum on a sideport with the needle of a similarly heated gas-tight syringe, and injected into a gas chromatograph (GC). The advantages of this system are: (1) Avoidance of the artefacts encountered in the assay of acetaldehyde in the blood; (2) suitability for sample collection at a site remote from the GC laboratory; (3) avoidance of sample loss by leakage, contamination, or partitioning into water condensed from breath; and (4) compatibility with a "nondedicated" GC lacking any special gas-collecting circuitry. A typical study of a normal human volunteer is described, demonstrating the rise and fall of the concentration of acetaldehyde and ethanol in the breath following the ingestion of an oral dose of ethanol. 相似文献
22.
Aorto-iliac aneurysms may entrap the ureters in perianeurysmal fibrosis, causing medial ureteral deviation and/or obstruction. The latter has been described only in male patients; a further 5 cases due to iliac and 3 to aortic aneurysm are reported. The radiologic picture resembles retroperitoneal fibrosis; the correct diagnosis may be suggested when ureteral tethering or narrowing lies near arterial calcification. Sonography is usually the most appropriate investigation to confirm the diagnosis. When sonography shows an aortic aneurysm, the kidneys should be scanned to rule out hydronephrosis. Similarly, films of the kidneys should be obtained when an abdominal aneurysm is demonstrated by aortography. 相似文献
23.
Joan SK Ng FRCS William Wong FRCP Ricky WK Law FRCS Joannie Hui MRCP Esther N Wong MRCP Dennis SC Lam FRCOphth 《Clinical & experimental ophthalmology》2001,29(4):239-243
Purpose : To investigate ocular complications arising from nephrotic syndrome and/or its treatments in children. Methods : A cross‐sectional study was conducted in a teaching hospital. A total of 31 paediatric patients with nephrotic syndrome were studied. Comprehensive ophthalmic assessments on best‐corrected visual acuity, intraocular pressure, slit‐lamp and fundus examination were taken. Information regarding histological diagnosis of nephrotic syndrome and its treatment regimen in each patient was reviewed and analysed. Results : Bilateral posterior subcapsular cataracts were detected in three of 29 patients (10.3%) who received steroid therapy. Two had normal vision while one had visual acuity reduced to 6/15 in both eyes. The age of onset of the nephrotic syndrome in these three patients was 2 years, which was significantly younger than those without cataract (5.4 ± 3.2 years, P < 0.001). Three patients (9.7%) had isolated asymptomatic fundal findings of tortuous and dilated retinal vessels. Hypertensive retinopathy was found in one patient (3.2%). No steroid‐induced glaucoma, uveitis, ocular infection, or other eye complications related to the use of steroids or other immunosuppressive agents were noted. Conclusions : Children who have nephrotic syndrome often require prolonged, intermittent high dose of systemic corticosteroid therapy. Paediatricians should be aware of the potential risk of developing steroid‐related complications, especially posterior subcapsular cataract. It appears to have a higher risk when steroid therapy is used in very young patients. Early detection would help to prevent amblyopia development, particularly in the group of immature eyes. 相似文献
24.
Joost R. M. Van Der Sijp MD Dr. Michael A. Kamm MD MRCP FRACP Jeremy M. D. Nightingale MBBS MRCP Keith E. Britton MD MSC FRCP Marie Granowska MD MSC Stephen J. Mather PhD Louis M. A. Akkermans PhD John E. Lennard-Jones MD FRCP 《Digestive diseases and sciences》1993,38(5):837-844
Many patients with severe idiopathic constipation complain of upper gastrointestinal symptoms, and these often persist after subtotal colectomy. To determine if there is a disturbance of upper gastrointestinal motility in this condition, we have studied gastric emptying for solids (111In-containing pancake) and liquids (99mTc-containing orange, juice) for a longer period after a meal (6 hr) than in previously reported gastric emptying studies. Small bowel transit for solids was also measured. All patients had emptied their colon the day before the study. Twelve women (mean age 36 years) with a bowel frequency of less than once per week, proven slow intestinal transit, and a normal diameter colon were studied. Twelve healthy controls (eight female and four male, mean age 33) were also studied. As a group the constipated patients demonstrated no statistically significant delay in emptying during the first 3 hr, although the emptying rate for three of 12 individuals fell outside the normal range. However, at 6 hr after ingestion of the meal, six of 10 patients had residual gastric contents greater than normal-up to 48% solid residue (median: 11% for patients and 0% for controls,P<0.01) and 40% of liquid (median 9% vs 0%P<0.01). Three of four patients with upper gastrointestinal symptoms 6 hr after the meal had gastric retention of solids markedly outside the normal range (48%, 32%, and 16%; normal<4%). Small bowel transit time was assessed as the time for the solid phase to pass from the duodenum to the cecum; the constipated patients demonstrated delayed transit (median: 75 vs 55 min,P<0.01). Effectiveness of small bowel transit was assessed by the proportion of solids in the cecum at the time the stomach had emptied 50% of the solid meal; this was reduced in the patients (median: 6 vs 18%,P<0.01). All patients with normal gastric emptying had normal small bowel transit, and all those with delayed gastric emptying had prolonged small bowel transit. Colonic transit of the radioisotope was slow in all patients (head of the radioisotope column, cecum to stool, median: 96 vs 31 hr,P<0.01). Many patients with severe idiopathic constipation have a disturbance of gastric and small bowel transit that may be related to symptoms and that have implications for treatment. 相似文献
25.
What do we need to know about nonA—to-E viral hepatitis? 总被引:3,自引:0,他引:3
The list of potential hepatotrophic viruses continues to grow, with the recent discovery of the GB virus-C, the TT virus,
and the SEN virus. Prevalence rates of the GB virus-C have ranged from 1.2% to 13% among healthy blood donors from all over
the world. Higher prevalence rates have been reported among intravenous drug users. Similarly, the TT virus has a global distribution.
However, in spite of numerous reports of the presence of both of these viruses in various kinds of liver diseases, definite
evidence linking it to a specific disease or illness is lacking. The SEN virus is thought to be a novel viral agent that may
be linked to cryptogenic chronic hepatitis, but data are awaited. 相似文献
26.
Dr. Linda H. Pololi MB MRCP Susan Potter BS RN 《Journal of general internal medicine》1996,11(9):545-547
We designed and evaluated a program to teach internal medicine residents behavioral counseling skills for multiple risk factor modification. Integrating physician-patient communication, negotiation skills, and the transtheoretical model of behavior change, we used small group discussion and standardized patients. The 18 participating residents increased their ability to modify patient behavior during videotaped interviews, mean pretest/posttest score: 33.1/40.1 (Student’s pairedt test, p<.0001). Physician self-efficacy in screening for risk factors and effecting behavioral change in patients was increased (p<.0001), as were positive attitudes toward psychosocial factors (p<.003). Our teaching effectively increased the residents’ self-efficacy and performance of behavioral counseling. 相似文献
27.
28.
Performance of manual hyperinflation: consistency and modification of the technique by intensive care unit nurses during physiotherapy 下载免费PDF全文
29.
Long‐term outcomes with first‐ vs. second‐generation drug‐eluting stents in saphenous vein graft lesions 下载免费PDF全文
Nagendra R. Pokala BS Rohan V. Menon BS Siddharth M. Patel BS George Christopoulos MD Georgios E. Christakopoulos MD Anna P. Kotsia MD Bavana V. Rangan BDS MPH Michele Roesle RN Shuaib Abdullah MD Jerrold Grodin MD Dharam J. Kumbhani MD SM MRCP Jeffrey Hastings MD Subhash Banerjee MD Emmanouil S. Brilakis MD PhD 《Catheterization and cardiovascular interventions》2016,87(1):34-40
30.
Routine invasive versus selective invasive strategies for Non‐ST‐elevation acute coronary syndromes: An Updated meta‐analysis of randomized trials 下载免费PDF全文