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61.
Davidson AG 《Journal of pharmaceutical and biomedical analysis》1985,3(4):329-334
The effects of variation of temperature in the range 0 degrees -40 degrees C on the zero and second derivative ultraviolet absorption spectra of ten compounds have been investigated. When the temperature of the solutions was increased, most of the substances showed a linear reduction of maximum absorbance (A(max)), with temperature coefficients of -0.07 +/- 0.03% per degree. The second derivative amplitudes of all the substances were reduced, with temperature coefficients (-0.1 to -0.5% per degree) that bore no significant relationship to those of the corresponding A(max) values. These effects on the extrema of the derivative spectra are explained by the small reduction in curvature at the corresponding wavelengths of the fundamental spectra, that occurs with increasing temperature. The precise and accurate assay of substances by derivative UV spectrophotometry requires that the temperatures of the standard and sample solutions are identical at the time of measurement. 相似文献
62.
A. Marczell H. Rosen H. Spoula 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1987,371(3):177-181
Zusammenfassung Es wird anhand einer konsekutiven Serie über eine modifizierte fortlaufende Nahttechnik am Colon berichtet, die gerade bei älteren Patienten eine sichere und rasche Methode der Anastomosierung darstellt. Die klinisch relevante Insuffizienzrate sowie auch die Letalitätsrate betrugen in dieser Serie je 2%, wobei die Ursachen für die Letalität aber keine Folge der Insuffizienz waren. Die Komplikationsrate betrug 11%, die urologischen Komplikationen mit 6% standen hierbei im Vordergrund.
A consecutive series of 100 resections of the colon using a modified technique of continuous (running away) suture
Summary Based on a consecutive series it is reported about a modified type of continuous suture on the colon, used especially in elderly patients for being a secure and prompt method of anastomosing. The rate of insufficiency and mortality, as far as the clinical relevance is concerned, turns out to be 2% each and there was no relation between mortality and insufficient anastomosis. The complication rate was 11%, whereby the urological complications predominated with 6% of the total.相似文献
63.
Methods for non-invasive detection of ventricular late potentials--a comparative multicenter study 总被引:2,自引:0,他引:2
M Oeff E R von Leitner R Sthapit G Breithardt M Borggrefe U Karbenn T Meinertz R Zotz W Clas V Hombach 《European heart journal》1986,7(1):25-33
To evaluate the methodological problems of the non-invasive registration of late potentials the results obtained with four different averaging devices in the same 109 patients were compared. The high-resolution ECG was obtained from the body surface, high-gain amplified and filtered. With the averaging technique, the improved signal-to-noise ratio was able to detect low-amplitude cardiac activity. The incidence of late potentials detected with the four averaging systems, whose characteristics are described, ranged between 12% and 21%. Corresponding positive results were obtained in 5.5%, corresponding negative results in 68.8%. The reasons for differing results were mainly due to differences in visual or automatic interpretation of the registered fractionated electrical cardiac activity. Additionally, the determination of the end of QRS using the QRS width, obtained from reference leads, may influence the specificity of the methods. 相似文献
64.
Hans Peter Kaesermann 《Psychopharmacology》1986,89(1):31-37
Based upon the ethological element stretched attend to a conspecific, which reflects ambivalence between approach and avoidance in a social context, a simple, non-social behavioral method for studying conflict behavior in mice was investigated. Thus, stretched attend posture (SAP) and other behavioral acts were measured in untreated or drug-treated mice which were individually placed on a perforated platform previously rubbed with foreign male urine and boluses. In naive, untreated mice, the occurrence of SAP was partly housing- and lighting-dependent. After repeated exposure to the test situation, untreated mice showed less SAP, whereas static behavior (immobility and activity at rest) was increased. After single oral treatment with diazepam, clobazam or phenobarbital, SAP was reduced, whereas static behavior or going forwards in SAP was increased. Chlorpromazine and imipramine did not influence SAP. In naive mice, single IP injection of pentylenetetrazol did not significantly increase SAP. The similarity in the behavioral response between experienced, untreated mice and naive animals treated with diazepam, clobazam, or phenobarbital suggests that drug-treated mice behaved as if they were already familiar with the test situation. The latter drug-induced changes are consistent with data obtained in animal models which are based upon the measurement of behavioral inhibition. Under the present test conditions, pentylenetetrazol did not show anxiogenic properties. Nevertheless, the SAP test, based primarily on the measurement of the ambivalence element, offers a simple procedure for examining the conflict-reducing properties of drugs, dispensing with the need of noxious stimuli or prior training.Some of these results were presented at the 15th Annual USGEB/USSBE Meeting in Fribourg, Switzerland (17–18 March 1983) and, published in abstract form in Experientia (1983) 39(6):681–682 相似文献
65.
《Health & place》2021
This study broadens contextual environments to include adults’ activity spaces—inside and outside the residential neighborhood—to examine how contextual exposures shape type 2 diabetes risk. We use novel longitudinal data from the Los Angeles Family and Neighborhood Survey, construct time-weighted exposure measures of adults’ social-structural and healthy resource environments, and execute random effects logistic models predicting the probability of being diabetic. Results indicate that residential and activity space exposures are independently associated with adult diabetes, and that residential and activity space healthy resources combine to influence diabetes risk in synergistic ways. Living in more socioeconomically advantaged neighborhoods reduces diabetes risk, particularly when spending time in activity spaces with greater access to recreational facilities. Moreover, healthier activity space environments may compensate for living in neighborhoods devoid of healthy food options to lessen diabetes risk. Adopting an activity space framework can inform multilevel interventions aimed at alleviating type 2 diabetes and other chronic ailments. 相似文献
66.
Expression of activation markers on alveolar macrophages in allergic asthmatics after endobronchial or whole-lung allergen challenge 总被引:4,自引:0,他引:4
Viksman MY Bochner BS Peebles RS Schleimer RP Liu MC 《Clinical immunology (Orlando, Fla.)》2002,104(1):77-85
We examined the effect of endobronchial (EB) or whole-lung (WL) challenge with ragweed or Timothy grass extract on alveolar macrophage (AM) activation. Expression of 17 constitutive activation markers on AM was examined by flow cytometry. Late-phase bronchial obstruction was greater after WL challenge, while changes in bronchoalveolar lavage cytology (eosinophil accumulation) were greater after EB challenge. After EB challenge, levels of 10 of 17 markers (CD11a, CD11b, CD14, CD18, CD23, CD32, CD63, CD64, HLA-class I, and HLA-DR) were significantly increased (by 33-234%, P < 0.05). Six markers (CD16, CD29, CD33, CD35, CD44, CD71, and HLA-DQ) remained unchanged. Levels of seven markers following EB challenge (CD14, CD16, CD18, CD29, CD32, HLA-class I, and HLA DQ) correlated with airway sensitivity to methacholine. WL challenge only increased expression of HLA-class I. The different results obtained with the two challenge methods probably depend on higher local concentrations of allergen in the EB challenge. We suggest that activation of AM occurs following EB challenge with antigen in asthmatics. 相似文献
67.
Summary Clinical characteristics and the outcomes of 50 patients with confirmed subarachnoid haemorrhage (SAH) of unknown aetiology were evaluated. Twenty-nine of these patients were interviewed with a mean follow-up of 7.7 years. Seven patients experienced early rebleeding during hospitalization, and one patient experienced late rebleeding during the follow-up period.On admission to the hospital the consciousness level was clear in 43 of the patients, drowsy in 6, and semicomatose in only 1. Of 10 patients who underwent computerized tomography (CT) within 3 days after SAH, 6 showed no abnormal CT findings and 3 had mild subarachnoid blood. Another patient showed severe SAH. Neurological deficit due to symptomatic vasospasm persisted in only 1 case.Two patients died after re-bleeding during hospitalization, and two others died during the follow-up, thereby representing an overall mortality rate of 8%. Of the latter cases, one died of an unrelated disease, and the other died suddenly from an unknown cause. The remaining forty-six patients (92%) had a good outcome. These results confirm previously reported clinical characteristics, namely that the symptoms of the majority of such cases are mild, the incidence of symptomatic vasospasm is rare, the risk of late re-bleeding is very low (less than 1% per year), and the prognosis is good. The CT findings suggest that some of these features resulted from only mild SAH. Thus, SAH of unknown aetiology seems to be a disease entity with a good prognosis. 相似文献
68.
H. C. Korting M. Schäfer-Korting H. Hart P. Laux M. Schmid 《European journal of clinical pharmacology》1993,44(4):315-318
Summary The anti-inflammatory activity of hamamelis distillate has been evaluated with respect to drug concentration (0.64 mg/2.56 mg hamamelis ketone/100 g) and the effect of the vehicle (O/W emulsion with/without phosphatidylcholine (PC) in an experimental study. The effects were compared with those of chamomile cream, hydrocortisone 1% cream and 4 base preparations. Erythema was induced by UV irradiation and cellophane tape stripping of the horny layer in 24 healthy subjects per test. Skin blanching was quantified by visual scoring and chromametry. Drug effects were compared with one another and with an untreated control area, as well as with any action due to the vehicle.UV-induced erythema at 24 h was suppressed by low dose hamamelis PC-cream and hydrocortisone cream. Hydrocortisone appeared superior to both hamamelis vehicles, hamamelis cream (without PC) and chamomile cream. The latter preparation was also less potent than hamamelis PC-cream. Erythema 4 to 8 h after the stripping of the horny layer was suppressed by hydrocortisone (P0.05). Inflammation was also less pronounced following low dose hamamelis PC-cream and chamomile cream. Hamamelis PC-cream, however, appeared less potent than hydrocortisone. In general, visual scoring was more discriminatory than chromametry.The results have demonstrated an anti-inflammatory activity of hamamelis distillate in a PC-containing vehicle. A fourfold increase of drug concentration, however, did not produce an increase in activity. 相似文献
69.
High exposures to organic solvents among graffiti removers 总被引:3,自引:0,他引:3
Helena Anundi Marie-Louise Lind Lennart Friis Nadja Itkes Sven Langworth Christer Edling 《International archives of occupational and environmental health》1993,65(4):247-251
Summary The exposure to organic solvents among 12 graffiti removers was studied. Health effects were also assessed by structured interview and a symptom questionnaire. Blood and urine samples were collected at the end of the day of air sampling. The concentrations of dichloromethane, glycol ethers, trimethylbenzenes and N-methyl-2-pyrrolidinone in the breathing zone of each worker were measured during one working day. The 8-h time-weighted average exposure to dichloromethane ranged from 18 to 1200 mg/m3. The Swedish Permissible Exposure Limit value for dichloromethane is 120 mg/m3. The air concentrations of glycol ethers, trimethylbenzens and N-methyl-2-pyrrolidinone were low or not detectable. No exposure-related deviations in the serum concentrations of creatinine, aspartate transaminase, alanine transaminase, -glutamyl transpeptidase or hyaluronan or the urine concentrations of 1-microglobulin, R2-microglobulin or N-acetyl--glucos-aminidase were found. Irritative symptoms of the eyes and upper respiratory tract were more prevalent than in the general population. This study demonstrates that old knowledge about work harzards is not automatically transferred to new professions. Another aspect is that the public is also exposed as the job is performed during daytime in underground stations. At least for short periods, bystanders may be exposed to high concentrations of organic solvent vapours. People with predisposing conditions, e.g. asthmatics, may risk adverse reactions. 相似文献
70.
M. van Dormolen C. A. W. M. Hertog F .J H. van Dijk M. A. J. Kompier R. Fortuin 《International archives of occupational and environmental health》1990,62(4):279-287
Summary A literature review was performed on the subject of combined exposure to stressors in the working situation. A general, dynamic model of workload served as the theoretical framework for the study. In this model, every factor that triggers a physiological or psychological response in the worker is regarded as a stressor. Decision latitude plays an important role in the model. A quantitative and qualitative analysis was performed on the available literature. It was concluded that the stressors that appear in studies on combined exposure stem mostly from the physical, chemical and biological environment. The task contents, the labor conditions, social relationships at work and the decision latitude are considerably less often studied in relation to combined exposure. It is concluded that important concepts in the study of combined exposure (e.g. interaction, independence, synergism, antagonism) are often quite carelessly mentioned in the literature. Explicit definition of these concepts is lacking in many publications. Establishment of maximum exposure levels is not yet possible for most stressor combinations. Examples are given of combinations that do allow more or less definite conclusions. It is recommended that more studies should be interdisciplinary organized. More studies are necessary in the field, studying effects of long exposure periods in the working population instead of studying students in laboratory situations. Exposure of susceptible groups, such as older workers and partially disabled workers, deserves special attention. 相似文献