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11.
Sjamsoedin DA Schulten EA van der Waal I 《Nederlands tijdschrift voor tandheelkunde》1994,101(7):262-263
What should a dentist or dental student do when he happens to be HIV-seropositive? Should he or she disclose the disease to the patients or, in case of a student, to the university? Does he has to give up his practice or perhaps not even open one? Apparently, the legal regulations differ in various parts of the world. In the Netherlands dentists are advised to take their own responsibility in this matter. 相似文献
12.
B. M. Ure A. M. Holschneider D. Schulten W. Meier-Ruge 《Pediatric surgery international》1997,12(5-6):377-382
A prospective study of 141 consecutive patients with intestinal neuronal malformations is presented. The single malformation of the autonomic nervous system that always required surgical intervention was aganglionosis. Giant ganglia, reduced parasympathetic tone, immature ganglia, and hypogenetic or heterotopic nerve cells were seen in all forms of malformations. However, the incidence in specific malformations was variable. Multiple giant ganglia were identified in all patients with intestinal neuronal dysplasia (IND) type B, but also in various other malformations. Heterotopic nerve cells in the myenteric plexus were seen in the proximal segment of 15 of 74 patients (20.3%) with aganglionosis and 5 of 9 patients (55.6%) with hypoganglionosis. A significant impact on symptoms was found for IND type B: 34 (45.9%) of 74 children with aganglionosis had associated IND type B, and these children more frequently developed ileus (P < 0.001) and more often needed a second resection (P < 0.05) compared to those with isolated aganglionosis. This indicates an additive effect of both malformations, and therefore, in these patients an extended resection should be carried out.Twelve of 67 patients (17.9%) without aganglionosis needed resection for untreatable constipation. This included 7 of 9 children with hypoganglionosis, both patients with heterotopia of the myenteric plexus, 1 of 20 with isolated IND type B, and 2 of 12 with reduced parasympathetic tone. None of the patients with immaturity, heterotopia of the submucous plexus, or mild dysganglionosis required surgery. Six children (8.9%) without aganglionosis underwent sphincteromyotomy and 2 with IND type B had a temporary colostomy. At follow-up (mean 2.4 ± 1.4 years), the outcome in patients with resected aganglionosis was better than in patients who had resections for other malformations; 49 (69%) of 71 patients with aganglionosis were asymptomatic compared to 4 (33.3%) of 12 with other malformations (P < 0.05). It is concluded that some intestinal malformations have a relevant clinical impact. However, the severity of symptoms in the individual patient may not be explained by specific histochemical findings from a limited number of mucosal biopsies. The pathognomonic histochemical criteria of isolated IND typeB — immaturity, reduced parasympathetic tone, heterotopia of the submucous plexus, and mild dysganglionosis —rarely require surgical therapy and should be treated conservatively. 相似文献
13.
Ionizing radiation is a carcinogen that induces oxidative DNA damage. 8-
Hydroxy-2'-deoxyguanosine (8-OHdG) is a relatively abundant, mutagenic
lesion that is widely regarded as a reliable index of oxidative DNA damage.
The purpose of this study was to examine the effects of X- radiation on
levels of 8-OHdG in the context of an experimental model for breast cancer
in which chronic radiation exposure has been shown to be carcinogenic in
Sprague-Dawley rats. A secondary objective of this study was to determine
if the use of phenol during DNA isolation affected the concentration of
8-OHdG subsequently measured. Our results indicate that a profoundly
carcinogenic dose of radiation induced a small but significant increase in
8-OHdG concentration in mammary gland DNA, and that the use of a
phenol-based versus a salt-based method of DNA isolation had no significant
impact on the levels of 8-OHdG detected in either control or irradiated
tissue.
相似文献
14.
van Kranen HJ; van Iersel PW; Rijnkels JM; Beems DB; Alink GM; van Kreijl CF 《Carcinogenesis》1998,19(9):1597-1601
The variation in colorectal cancer (CRC) incidence worldwide strongly
suggests a role for dietary influences. Based on epidemiological data,
protective effects of vegetables and fruit intake on CRC are widely
claimed, while other data indicate a possible increased CRC risk from
(higher) dietary fat intake. Therefore, we have investigated single and
interactive effects of dietary fat and a vegetable-fruit mixture (VFM) in
the ApcMin mouse, a mouse model for multiple intestinal neoplasia. In this
study, four different diets (A-D) were compared, which were either low in
fat (20% energy diets A/B) or high in fat (40% energy diets C/D). In
addition, 19.5% (wt/wt) of the carbohydrates in diets B and D were replaced
by a freeze-dried VFM. The diets were balanced so that they only differed
among each other in fat/carbohydrate content and the presence of specific
plant-constituents. Because the initiation of intestinal tumors in ApcMin
mice occurs relatively early in life, exposure to the diets was started in
utero. Without the addition of VFM, mice maintained at a high-fat diet did
not develop significantly higher numbers of small or large intestinal
adenomas than mice maintained at a low-fat diet. VFM added to a low-fat
diet significantly lowered multiplicity of small intestinal polyps (from
16.2 to 10.2/mouse, 15 animals/group), but not of colon tumors in male
ApcMin mice only. Strikingly, addition of VFM to female mice maintained on
a low-fat diet and to both sexes maintained on a high-fat diet
significantly enhanced intestinal polyp multiplicity (from 16.5 to 26.7
polyps/mouse). In conclusion, our results indicate that neither a lower fat
intake nor consumption of VFM included in a high-fat diet decreases the
development of polyps in mice genetically predisposed to intestinal tumor
development.
相似文献
15.
16.
Funk Walter Seitz G. Schimert Wieneke W. Lang R. Rieffert Kleinfelder Kühn Burmeister Böhm S. Norpoth Hungerland Schemensky H. Kalk W. Schöndube Schulten J. Ulbricht H. Major Margarete Karlbaum Grüning Thiele W. Tischendorf Stechele F. Krause Streicher Bross Zierz Soehring Gänshirt Ulrich Fleck 《Journal of molecular medicine (Berlin, Germany)》1952,30(9-10):230-237
17.
18.
19.
MUHAMMAD N RAZA MUHAMMAD HADID CHARLES E KEEN CORALIE BINGHAM ANDREW HJ SALMON 《Nephrology (Carlton, Vic.)》2012,17(8):748-753
Background: The use and timing of steroids in the management of acute tubulointerstitial nephritis (ATIN) remains debatable. Aims: To determine the incidence and aetiology of ATIN in our unit, and to examine trends in the use of steroids and their impact on renal outcomes. Methods: Patients with a histological diagnosis of ATIN over a 9‐year period were identified and divided into steroid‐treated (StG) and steroid‐naïve groups (SnG). Mean change in estimated glomerular filtration rate (eGFR) was determined. Results: Forty‐nine patients had ATIN as their main diagnosis, 67% of cases were drug‐induced, and proton pump inhibitors (PPI) were the second commonest implicated drug category. Majority (75%) of patients received steroids, and eGFR improved to a significantly greater degree in these steroid‐treated patients (3.4‐fold improvement vs 2.0‐fold in SnG; P < 0.05, unpaired t‐test). Despite comparable eGFR at presentation (StG: 11.7; SnG: 15.4), steroid‐treated patients were less likely to receive dialysis, although not significantly so (OR 0.27; 95% CI 0.06–1.15, P = 0.066, chi‐squared test). However, there was no significant relation between the degree of eGFR improvement and delay in starting steroids (Pearson r = ?0.25, P > 0.45), and no difference in eGFR at the time of last follow‐up (StG: 33 ± 3; SnG: 32 ± 7; P > 0.9, unpaired t‐test). Conclusion: StG patients had a greater degree of improvement in renal function, but with no correlation between degree of improvement in eGFR and delay in starting steroids, and similar eGFR values at final follow‐up. PPI were the second commonest drug category among drug‐induced cases. 相似文献
20.
Expression of fibrinogen receptors during activation and subsequent desensitization of human platelets by epinephrine 总被引:2,自引:0,他引:2
Epinephrine causes platelet aggregation and secretion by interacting with alpha 2-adrenergic receptors on the platelet surface. Platelet aggregation requires the binding of fibrinogen to a specific receptor on the membrane glycoprotein IIb-IIIa complex. Although the IIb-IIIa complex is identifiable on the surface of resting platelets, the fibrinogen receptor is expressed only after platelet activation. The current studies were designed to examine the effect of occupancy of platelet alpha 2-adrenergic receptors by epinephrine on the expression of fibrinogen receptors and on the aggregation of platelets. The ability of epinephrine to induce the expression of fibrinogen receptors was studied under two different conditions: acute stimulation (less than 1 min) and prolonged stimulation (50 to 90 min), the latter of which is associated with a reduction or "desensitization" of the platelet aggregation response. Expression of the fibrinogen receptor was monitored with 125I-fibrinogen as well as with 125I-PAC-1 (PAC-1), a monoclonal antibody that binds to the glycoprotein IIb-IIIa complex only after platelets are activated. Epinephrine caused an immediate increase in PAC-1 and fibrinogen binding that was dependent on occupancy of the alpha 2-receptor by epinephrine and on the presence of extracellular free Ca (KCa = 30 mumol/L). By itself, 1 mmol/L Mg was unable to support induction of the fibrinogen receptor by epinephrine. However, it did decrease the Ca requirement by about two orders of magnitude. Prolonged stimulation of unstirred platelets by epinephrine led to a 70% decrease in the aggregation response when the platelets were subsequently stirred. Despite their decreased aggregation response, desensitized platelets bound PAC-1 and fibrinogen normally, indicating that the loss of aggregation was not due simply to a decrease in fibrinogen receptor expression. Although desensitization was not affected by pretreatment of the platelets with aspirin, it was partially prevented when extracellular Ca was chelated by EDTA during the long incubation with epinephrine. These studies demonstrate that once platelet alpha 2-adrenergic receptors are occupied by epinephrine, extracellular Ca is involved in initiating the aggregation response by supporting the induction of the fibrinogen receptor and the binding of fibrinogen. Furthermore. Ca-dependent reactions subsequent to fibrinogen binding may be necessary for maximal platelet aggregation and are impaired when platelets become desensitized to epinephrine. 相似文献