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141.
Previous occupational survey studies have identified waiter and cook as possible high risk occupations for cancer. However, few cohort studies have been performed among persons in the restaurant business, and we therefore have analyzed cancer incidence in two cohorts of Norwegian waiters and cooks. The cohorts consisted of skilled male workers, 1,463 waiters and 2,582 cooks, who received their craft certificate between 1958 and 1983. The cohorts were followed from 1959 through 1991. The standardized incidence ratio (SIR) for all causes of cancer was 1.4 (95 percent confidence interval [CI]=1.2–1.7] for waiters, and 1.1 (CI=0.9–1.4) for cooks. Cancers of the tongue, mouth, pharynx, larynx, esophagus, and liver were grouped together as alcohol-associated cancers. SIR for these cancers combined was 5.1 (CI=3.4–-7.4) for waiters and 4.2 (CI=2.2–7.2) for cooks. For lung cancer, SIR was 2.0 (CI=1.3–2.9) for waiters and 0.7 (CI=0.2–1.7) for cooks. For alcohol-associated cancers, the analysis carried out according to number of years since first employment showed a larger number of cases than expected for both occupations in all time-periods. The excess of lung cancer cases among waiters appeared after 30 years or more of employment. The study shows that waiters and cooks are at high risk of cancers associated with alcohol consumption, and that waiters, in addition, show high rates for lung cancer. The hypothesis of an occupational lung-cancer risk in cooks was not supported by this study.Dr Kjerheim and Mr Andersen are with The Cancer Registry of Norway. Address crrespondence to Dr Kjerheim, The Cancer Registry of Norway, Institute for Epidemiological Cancer Research, Montebello, 0310 Oslo, Norway. This project was supported by grants from the Confederation of Norwegian Business and Industry.  相似文献   
142.
Summary One hundred subjects with normal knees and 47 patients with chronic rupture of the anterior cruciate ligament were tested in the Genucom Knee Analysis System; the 13 different laxity tests were carried out on both knees. Measurements on right and left knees in normal subjects showed that only the lateral pivot shift test, performed at 25° of knee flexion, had a good side-to-side correlation, but did not differentiate the involved and uninvolved knees in the patients with anterior cruciate ligament deficiency. The sensitivity of the lateral pivot shift was 30% and specificity 91%. The corresponding figures for the anterior drawer test at 30° flexion using 93 N force were 45% and 88%. Measurements showed great variation. Care should be taken in interpreting the results from the Genucom System. It should be considered as an experimental device with little value in assessing patients with anterior cruciate ligament deficiency.
Résumé Cent personnes avec des genoux normaux et 47 patients avec une rupture chronique du ligament croisé antérieur ont été testés par le système d'analyse du genou Genucom. Un total de 13 différents tests de laxité contenus dans le protocole Genucom ont été effectués sur les deux genoux. L'analyse des mesures faites sur les genoux droit et gauche de sujets normaux a montré qu'un seul test, le Lateral Pivot Shift exécuté sur le genou en flexion de 25°, avait une bonne corrélation entre un côté et l'autre, mais sans être capable de distinguer le genou atteint du genou sain chez les patients ayant un ligament croisé antérieur déficient. La sensibilité de ce test était de 30% et sa spécificité de 91%. La sensibilité du tiroir antérieur sur le genou en flexion de 30°, avec une force de 93 Newton, était de 45% et sa spécifité de 88%. Les mesures ont généralement montré de grandes variations dont il faut tenir compte pour interpréter les résultats du Genucom. Celui-ci doit être considéré comme un instrument d'expérience et il n'a que peu d'utilité pour l'évaluation des patients présentant un déficit du ligament croisé antérieur.
  相似文献   
143.
Bromazepam was compared with placebo and with chlorprothixene in a randomized, double-blind group-comparative multicenter trial in general practice. Two hundred and forty-five patients with generalized anxiety disorder (DSM-III 1980) were treated for 2 weeks with two daily doses of bromazepam, 3 mg or chlorprothixene, 15 mg or placebo. Median reductions in Hamilton Anxiety rating were 12 (bromazepam), 10.3 (chlorprothixene) and 7.3 (placebo). The study revealed significant superiority of bromazepam over placebo (median differences 3.3, 95% confidence limits: 0.3 and 6.1) but not over chlorprothixene (median difference 1.4, 95% confidence limits –0.8 and +3.5). Significantly higher rates of tiredness, sedation and hypersomnia were found on bromazepam and chlorprothixene compared to placebo. Tolerance was rated as at least good in 85.6% on bromazepam, in 86% on chlorprothixene and in 87.8% on placebo. Neither previous psychopharmacological treatment nor presence of psychosocial stress were of perceptible influence. Bromazepam and chlorprothixene are both superior to placebo in generalized anxiety states treated in general practice, but spontaneous improvements/placebo effects are substantial.General practice The following general practitioners are gratefully acknowledged for their excellent co-operation: K. Andreasen (Grenaa), T. Andreasen (Helsingoer), C. Bjerre-Christensen (Viby J), J. Brix (Aabenraa), N.B. Caning (Stokkemarke), N. Christensen (Odense), P. Dehn-Jensen (Lyngby), J. Eggert (Langebaek), H. Fuglsang-Damgaard (Havndal), I. Fraemohs (Allingaabro), J. Gylling (Nykoebing Sjaelland), E. Halkjaer-Soerensen (Roedding), B. Hansson (Frederiksvaerk), C. Hauge (Espergaerde), S. Hede (Aalborg), G. Jensen (Copenhagen S), T. Knudsen (Arden), P. Kofod (Vejle), K. Kraen (Varde), V. Lade (Hjoerring), S. Mehlsen (Auning), J. Meyer-Christensen (Hobro), R. Michael (Langebaek), J. Munch (Oersted), L. Moeller-Hansen (Alleroed), U. Moeller (Graasten), K. Nielsen (Malling), S. Kjaerem Nielsen (Copenhagen), P.V. Nielsen (Odense), J. Peulicke (Espergaerde), O. Ravn (Roedding), C.U. Rosenberg (Aarhus), J. Rude (Goerlev), S. Spangsberg (Holbaek), H. Soegaard (Oelgod), O. Tang (Hoersholm)  相似文献   
144.
Structures of alternative pathway proteins have offered a comprehensive structural basis for understanding the molecular mechanisms governing activation and regulation of the amplification pathway of the complement cascade. Although properdin (FP) is required in vivo to sustain a functional alternative pathway, structural studies have been lagging behind due to the extended structure and polydisperse nature of FP. We review recent progress with respect to structure determination of FP and its proconvertase/convertase complexes. These structures identify in detail regions in C3b, factor B and FP involved in their mutual interactions. Structures of FP oligomers obtained by integrative studies have shed light on how FP activity depends on its oligomerization state. The accumulated structural knowledge allows us to rationalize the effect of point mutations causing FP deficiency. The structural basis for FP inhibition by the tick CirpA proteins is reviewed and the potential of alphafold2 predictions for understanding the interaction of FP with other tick proteins and the NKp46 receptor on host immune cells is discussed. The accumulated structural knowledge forms a comprehensive basis for understanding molecular interactions involving FP, pathological conditions arising from low levels of FP, and the molecular strategies used by ticks to suppress the alternative pathway.  相似文献   
145.
Tumor-infiltrating lymphocytes (TIL) are often found in malignant breast tumors, and have been claimed to be of prognostic value. It has been proposed that TIL may represent an enriched population of tumor-specific cytotoxic lymphocytes, reacting with antigenic determinants on the tumor cell surface through the T cell receptor (TCR) complex. We have studied the phenotype, cytotoxicity, and expression of TCR variable (V) alpha and beta chain on in vitro IL-2-cultured TIL isolated from primary malignant breast tumors from 11 patients. 10/11 cultures were dominated by CD4(+) (T-helper) cells. The different TIL cultures exhibited varying levels of cytotoxicity against the natural killer (NK)-sensitive cell line K562 and breast cancer cell line T47D. The level of clonality, as measured by PCR-based analyses of usage of the different V segments was low, as only a few tumors showed patterns of restricted V gene expression. The mean number of V alpha segments per TIL culture was higher than the number of V beta segments per culture. A significant negative correlation was observed between the number of CD4+ cells and the number of V beta segments per culture, and no other correlations between phenotypes and expression of any particular V segments were found. Neither was there any correlation between the expression of specific V alpha/V beta segments and cytotoxicity against allogeneic tumor cells.  相似文献   
146.
This paper presents a framework for comparison of screening programme designs, based on efficiency and cost effectiveness criteria. The design parameters, such as choice of screening interval, which population segments to screen and expected participation rates in the selected population segments, are varied simultaneously. The costs and effects for a range of existing and hypothetical screening programmes against cervical cancer are estimated, using a mathematical simulation model. On the basis of these estimates average costs per life year and marginal costs per life year are calculated for a range of programmes. These calculations result in the definition of a range of inefficient programmes. Moreover, it is illustrated that the cost effectiveness of the efficient screening programmes decreases at an increasing rate as programmes are intensified either by way of shortening the screening interval or extending the target population segment to encompass the very young and/or the very old. The conclusion of this paper is that one should probably not extend screening programmes against cervical cancer beyond screening women in the age group 25-59 years every 4 years. In addition, increasing the participation rate of this group is a more cost effective way of increasing the number of life years gained, rather than extending the target group or decreasing the screening interval.  相似文献   
147.
A woman's reproductive history influences her risk of breast cancer. The authors hypothesized that reproductive history also influences stage of disease at the time of diagnosis. The authors analyzed a population-based cohort of 1.5 million Danish women born between 1935 and 1978 for whom individual information on births was available. Between 1978 and 1994, 10,790 incident cases of breast cancer in women under 60 years of age were identified. Nulliparous women compared with parous women and women with a late age at first birth compared with an early age were at significantly increased risk of being diagnosed with a large tumor and with cancer that had spread to regional lymph nodes. However, such an association was not seen for women diagnosed with a small tumor and women with cancer that had not spread to regional lymph nodes. Reproductive history did not appear to influence the time interval from first symptoms to first physician visit ("patient delay") or the time interval from first physician visit to surgery ("doctor delay"). The authors conclude that reproductive history is associated both with incidence of breast cancer and with stage of the disease at diagnosis, indicating possible influences on tumor progression and growth rate. Intensified awareness is warranted to achieve earlier diagnosis among nulliparous women and women with a late age at first childbirth, with the hope of improving their prognosis.  相似文献   
148.
OBJECTIVES: Twelve countries were compared with respect to occupational class differences in ischemic heart disease mortality in order to identify factors that are associated with smaller or larger mortality differences. METHODS: Data on mortality by occupational class among men aged 30 to 64 years were obtained from national longitudinal or cross-sectional studies for the 1980s. A common occupational class scheme was applied to most countries. Potential effects of the main data problems were evaluated quantitatively. RESULTS: A north-south contrast existed within Europe. In England and Wales, Ireland, and Nordic countries, manual classes had higher mortality rates than nonmanual classes. In France, Switzerland, and Mediterranean countries, manual classes had mortality rates as low as, or lower than, those among nonmanual classes. Compared with Northern Europe, mortality differences in the United States were smaller (among men aged 30-44 years) or about as large (among men aged 45-64 years). CONCLUSIONS: The results underline the highly variable nature of socioeconomic inequalities in ischemic heart disease mortality. These inequalities appear to be highly sensitive to social gradients in behavioral risk factors. These risk factor gradients are determined by cultural as well as socioeconomic developments.  相似文献   
149.
Spiral organisms were isolated from an antral gastric mucosal biopsy specimen from a dyspeptic patient with gastritis. Only corkscrew-shaped organisms resembling "Gastrospirillum hominis" ("Helicobacter heilmannii") but no Helicobacter pylori-like organisms were seen in histological sections. H. pylori was not cultured from specimens from this patient. On the basis of biochemical reactions, morphology, ultrastructure, and 16S DNA sequencing, the isolated "G. hominis" was shown to be a true Helicobacter sp. very similar to Helicobacter felis and the "Gastrospirillum" but was separate from H. pylori. "G. hominis" is a pleomorphic gram-negative cork-screw-shaped, motile rod with 3 to 8 coils and a wavelength of about 1 micrometer. In contrast to H. pylori, it has up to 14 sheathed flagellar uni- or bipolar fibrils but no periplasmic fibrils. "G. hominis" grows under microaerobic conditions at 36 and 41 degrees C on 7% lysed, defibrinated horse blood agar plates within 3 to 7 days and can be subcultured under microaerobic but not under anaerobic conditions on media similar to those used for H. pylori and H. felis. The small translucent colonies were, in contrast to those of H. felis, indistinguishable from those of H. pylori. "G. hominis" is, like H. pylori and H. felis, motile, is oxidase, catalase, nitrite, nitrate, and urease positive, and produces alkaline phosphatase and arginine arylamidase. Like H. pylori and H. felis, it is sensitive to cephalothin (30-microgram disc), resistant to nalidixic acid (30-microgram disc), and sensitive to most other antibiotics. The 16S DNA sequence clusters "G. hominis" together with "Gastrospirillum," H. felis, Helicobacter bizzozeronii, Helicobacter salmonii, Helicobacter nemestrinae, Helicobacter acinonychis, and H. pylori.  相似文献   
150.
OBJECTIVES: The stretch reflex is functionally important during human locomotion. Muscle pain has been found to increase the stretch reflex amplitude during sitting, possibly due to an altered fusimotor drive. To further study the importance of altered fusimotor activity due to muscle pain we investigated the combined effect of muscle pain and motor task on the soleus stretch reflex. METHODS: Stretch reflexes were elicited before, during and after experimentally induced muscle pain in soleus (i.m. infusion of 6% saline) in 3 experiments: (1) in the relaxed soleus muscle and before, during and after an isometric ramp contraction (500 ms, 0-10 Nm), (2) at 3 different time periods during walking, and (3) at matched pain intensity and soleus activity during sitting and walking. RESULTS: Infusion of hypertonic saline into the soleus muscle caused a significant facilitated stretch reflex in the relaxed muscle (P<0.01), but not during walking or during sitting and walking at matched soleus EMG and matched pain levels. The infusion of isotonic saline (non-painful) did not cause any changes (P = 0.75). CONCLUSIONS: The main findings of the present study were that experimental muscle pain facilitated the stretch reflex during pain in the relaxed muscle, but caused no changes in stretch reflex amplitude during sitting and walking at higher "functional" background EMG levels.  相似文献   
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