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1.
C Leclercq G Maiani A Polito A Ferro-Luzzi 《Nutrition (Burbank, Los Angeles County, Calif.)》1991,7(5):350-354
The p-aminobenzoic acid (PABA) test has been successfully used as an indicator of completeness of 24-h urine collection in field studies of the general population. Our study was designed to investigate its validity for elderly people. Urinary excretion of fractionated oral doses of PABA was measured in 21 young control subjects (19-39 yr old) and 356 elderly (60-89 yr old) men and women. PABA excretion over 24 h was lower in elderly than in control subjects. Subjects aged greater than or equal to 70 yr had a lower recovery of the PABA dose than subjects aged 60-69 yr over the first 24 h, followed by a higher recovery over the next 24-48 h. The cumulative 48-h recovery was similar in all age classes of elderly subjects. However, 48% of the elderly subjects had a cumulative PABA recovery below the conventional cutoff for completeness (85%). These subjects also had consistently lower creatinine output and urinary volume. The lower 24-h urinary PABA recovery over 70 yr of age is interpreted to reflect the delayed renal clearance of the marker substance and indicates that the PABA test is unsuitable for this age group. The low 48-h cumulative recoveries found in all age classes of the elderly are thought to be caused by small unreported losses, which are recurrent in free-living populations. 相似文献
2.
Giuseppe Lippi Gian Luca Salvagno Martina Montagnana Franco Manzato Gian Cesare Guidi 《Blood coagulation & fibrinolysis》2007,18(5):525-528
Preparation of blood specimens is a major bottleneck in the laboratory throughput. Reliable strategies for reducing the time required for specimen processing without affecting quality should be acknowledged, especially for laboratories performing stat analyses. The present investigation was planned to establish a minimal suitable centrifuge time for primary samples collected for routine coagulation testing. Five sequential primary vacuum tubes containing 0.109 mol/l buffered trisodium citrate were collected from 10 volunteers and were immediately centrifuged on a conventional centrifuge at 1500 x g, at room temperature for 1, 2, 5, 10 and 15 min, respectively. Hematological and routine coagulation testing, including prothrombin time, activated partial thromboplastin time and fibrinogen, were performed. The centrifugation time was inversely associated with residual blood cell elements in plasma, especially platelets. Statistically significant variations from the reference 15-min centrifuge specimens were observed for fibrinogen in samples centrifuged for 5 min at most and for the activated partial thromboplastin time in samples centrifuged for 2 min at most. Meaningful biases related to the desirable bias were observed for fibrinogen in samples centrifuged for 2 min at most, and for the activated partial thromboplastin time in samples centrifuged for 1 min at most. According to our experimental conditions, a 5-10 min centrifuge time at 1500 x g may be suitable for primary tubes collected for routine coagulation testing. 相似文献
3.
4.
Effects of androgen treatment in impotent men with normal and low levels of free testosterone 总被引:1,自引:0,他引:1
Cesare Carani M.D. Dante Zini M.D. Augusto Baldini M.D. Luciano Della Casa M.D. Anna Ghizzani M.D. Paolo Marrama M.D. 《Archives of sexual behavior》1990,19(3):223-234
The relation between sexual function and serum free testosterone (fT) levels, which represent the active fraction of circulating testosterone, was evaluated. Two groups of impotent male subjects with mild hypogonadism were treated with oral testosterone undecanoate (TU); these men presented with tT/luteinizing hormone (LH) ratio and tT levels at the lower limits of normal. The first group had serum fT below 6.6 ng/ml, considered the lower normal value, according to our laboratory method, whereas the second group had normal fT limits. Administration of TU improved sexual function only in impotent men with low fT levels, but not in subjects with normal fT levels, even though the tT levels and the tT/LH ratio of the two groups were not significantly different. The results of our study suggest the presence of a minimun serum fT threshold, lying near the lower normal range, which determines the male sexual function. Moreover, serum fT levels were a more sensitive index than tT for identifying impotent men who can be successfully treated with androgens. 相似文献
5.
Total parenteral nutrition is now a broadly used method whose efficacy is confirmed, even if it is still not free from risk of complications. The Authors report their own clinical experience on 130 cases in the period 1981-1988. Complications were registered in 4.6% of the observed cases. They underline the problems relating to this subject. 相似文献
6.
Mario R. Angi Maurizio Clementi Cristina Sardei Ettore Piattelli Cesare Bisantis 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1993,231(10):580-585
The existence of a visual feedback control of eye growth in humans is controversal, as the contributions of genetic and environmental factors are still unknown. To evaluate the heritability of refractive defects, we measured ocular refraction in 19 monozygote and 20 dizygote twin pairs (mean age 5 years). Monozygosity was ascertained by a common chorion, similarity of somatic traits, and identical dermatogliphes and was confirmed in myopes by blood marker diagnosis. Ocular refractive defects and axial length were evaluated by eye-loplegic autorefractometry and biometry. By comparing identical and fraternal twins heritability of refractive defects was estimated to be 0.08–0.14; this low value indicates that the observed variability in refractive errors is nongenetic in origin. Three monozygote pairs were anisomyopic; differences between eyes in identical twins were related to the increased axial length of myopic eyes. In one eye, myopia was attributed to visual deprivation induced by a congenital cataract, while in five eyes it was correlated directly to the degree of astigmatic defects. The discordant axial length observed in monozygote twins is nongenetic. In agreement with previous findings reported in the literature, it is proposed that visual impoverishment of retinal images may play an early regulatory role in postnatal eye growth.Deceased 相似文献
7.
M Rengo V Terrinoni G Galati A De Cesare A Martinazzoli E Fiori M Borghese A Florio 《Minerva chirurgica》1990,45(7):469-476
Underlining the importance of Profundus Femoral Artery and its capacity to make up for lower limb's haemodynamics during obliterative arteriopathy, the Authors conceive a funnel-shaped intravascular prosthesis, Goretex constructed (PTFE), to introduce, in case of obstruction, in the artery lumen with a suitable instrument. The research is performed through ten oldster dogs whose average weight is twenty-four kilograms. Isolated the deep Femoral Artery and carried out an arteriotomy of about two centimetres on the Common Femoral Artery, we bring the prothesis in Profundis Femoral Artery and we fix it to the wall of the Common Femoral Artery with 8/O microsurgical dots. After thirty days, the arteriographic test shows the patency of the endoprosthesis with normal peripheral flow in nine animals out of ten. By virtue of this preliminary experiment, the Authors point out the semplicity of this intervention, also feasible in local anaesthesia, the good tolerability of the prosthesis and its perfect integration with the surrounding arterious wall, without shifts or dissecting laminar flows between the external prosthesis wall and the vessel lumen of the animal. 相似文献
8.
Luca Oscar Redaelli De Zinis Andrea Bolzoni Cesare Piazza Piero Nicolai 《European archives of oto-rhino-laryngology》2006,263(12):1131-1135
Lymph node (LN) metastases represent the most important negative prognostic factor in squamous cell carcinoma (SCC) of the oral cavity, even though controversies still exist regarding their management. The aim of this study was to retrospectively analyze our experience in surgical management of SCC of the oral cavity with particular focus on the prevalence and localization of lymph nodal metastases and recurrences. The clinical records of 89 consecutive patients treated from 1983 to 2002 by concomitant surgery on both the T and N sites, excluding those undergoing salvage surgery, were reviewed. A total of 119 neck dissections (ND) were performed. Survival outcomes were calculated by the Kaplan–Meier method, while univariate comparisons by the log-rank and non-parametric tests were performed between different groups of patients. Five-year overall and determinate survivals were 50 and 57%, respectively. LN metastases were observed in 52% (56% of these showing extracapsular spread) and their presence strongly correlated with determinate survival (p < 0.0001). The prevalence of clinical and occult nodal disease was not related to the pT status. Neck levels II (59%) and I (56%) were most frequently involved. Metastases to level IV accounted for 15% of positive LN, even though 28% of them turned out to be skip metastases. Five neck recurrences were observed, only one of which was salvaged by surgery. The high prevalence of clinical and occult LN metastases in this setting suggests that ND should be performed on a nearly routine basis, even for lesions with a low-T category and a cN0 neck. Moreover, ND should always encompass level IV due to the possibility of skip metastases, particularly in tumors involving the oral tongue. In patients with a cN+ neck, levels from I to V should be addressed, particularly in the presence of metastases at levels III and IV. 相似文献
9.
10.
Carbon dioxide laser salvage surgery after radiotherapy failure in T1 and T2 glottic carcinoma. 总被引:2,自引:0,他引:2
Roberto Puxeddu Cesare Piazza Maria C Mensi Gian Peppino Ledda Federico Argiolas Giorgio Peretti 《Otolaryngology--head and neck surgery》2004,130(1):84-88
OBJECTIVES: Recurrent glottic carcinoma after radiotherapy (RT) may be managed by open neck or endoscopic surgery. The impact of endoscopic treatment with CO(2) laser for recurrent glottic carcinoma after RT is reported. METHODS: We present the oncologic and vocal outcomes of a retrospective study based on a series of 16 patients with rT1 and rT2 glottic carcinoma who were endoscopically managed between February 1995 and December 1999 after RT failure. All patients were males with a mean age of 68.7 years (range, 50 to 87 years). Before RT, the lesions had been staged as T1 N0 in 11 patients and T2 N0 in 5, and after RT as rT1 N0 in 12 and rT2 N0 in 4. According to the European Laryngological Society classification, a total of 9 transmuscular, 3 total, and 4 extended cordectomies were performed. Mean follow-up was 45 months (range, 9 to 79 months). RESULTS: Endoscopic salvage surgery was successful in 14 patients. One of them developed a second recurrence and was definitively cured with an additional endoscopic procedure. Two of the 16 patients had recurrent disease after salvage laser surgery and died due to progression of disease. Ultimate local control with laser alone at 3 years was 87.1%, according to the Kaplan-Meier method. Laryngeal preservation was obtained in all survivors after endoscopic rescue surgery. Voice analysis showed a clear correlation between the amount of vocal cord tissue resected and decrease of the vocal outcome. CONCLUSIONS: The present series indicates that selected recurrences after primary RT for T1 and T2 glottic carcinoma are eligible for endoscopic salvage surgery with oncologic results comparable to those with open neck procedures but with a lower complication rate and a favorable functional outcome. 相似文献