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91.
M H Raasveld E Bloemena S Surachno R J ten Berge 《Nephrology, dialysis, transplantation》1992,7(6):530-533
T gamma/delta lymphocytes are able to perform allospecific cytotoxicity and natural killer cytotoxicity in vitro. However, very little is known about their function in vivo. To investigate the possible involvement of T gamma/delta lymphocytes in the immune response to renal allografts, fine-needle aspiration biopsies and peripheral blood of 15 renal transplant recipients were studied during the first 4 weeks after transplantation. In addition peripheral blood of patients before transplantation, half a year and one year after transplantation was studied. No increase in the percentage of T gamma/delta lymphocytes in the fine-needle aspiration biopsies, including those taken during acute rejection episodes, was found. A significant decrease in the percentage of T gamma/delta lymphocytes was observed in peripheral blood after transplantation. We conclude that T gamma/delta lymphocytes seem to play no major role in the immune response to renal allografts. 相似文献
92.
C. A. F. Tulleken A. van Dieren J. ten Veen F. H. Lopes da Silva 《Acta neurochirurgica》1982,61(1-3):227-240
Summary The local EEG, the local cerebral blood flow (1CBF), and the flow in the distal stump of the occluded middle cerebral artery were simultaneously recorded in 28 acute experiments in cats. Nembutal anaesthesia was used eleven times, and Halothane anaesthesia 17 times.The recordings were made via platinum electrodes: 12 in the ischaemic hemisphere, and 2–3 in the opposite non-ischaemic hemisphere. The flow in the occluded middle cerebral artery was recorded via a platinum electrode introduced into this artery via the transorbital approach. The changes in 1EEG, 1CBF, and middle cerebral artery flow were studied during normotension, hypertension, and hypotension. A beneficial effect of hypertension was noted in the acute phase of brain ischaemia. Hypertension counteracted also the diaschisis in the non-ischaemic part of the ischaemic hemisphere and in the opposite non-ischaemic hemisphere. A correlation between 1EEG changes and 1CBF changes was noted. In addition an interesting discrepancy was observed between the rapid H2 clearance in the middle cerebral artery stump and the much slower H2 clearance in the ischaemic brain area.Significant differences between experiments under Halothane and experiments under Nembutal anaesthesia were noted. In the acute phase those changes are probably the result of the different levels of blood pressure in those two groups. 相似文献
93.
Martijn ten Ham 《Drug safety》2003,26(14):991-997
Pharmaceutical products are not exempt from the practice of counterfeiting. In recent years, many reports have become available demonstrating the presence of fake medicines on the market. Several studies have demonstrated that they are quite often of bad quality. It is estimated that 5% of all world trade in branded goods is counterfeit, leading to huge financial losses for the pharmaceutical industry. But much more important, from a public health point of view, is that history has shown that such products may lead to a great health risk. The essence of counterfeit products and the reason they are so dangerous is the complete absence of quality control, since they are often indistinguishable from the genuine product. The existence of counterfeit drugs has long been ignored both by the pharmaceutical industry and by drug regulatory authorities. At present initiatives are being taken, nationally and internationally, to curb counterfeiting. It is now realised that a strong regulatory agency is essential, but the initiatives can only be successful if all parties concerned actively co-operate. 相似文献
94.
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
95.
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
96.
Positron emission tomography (PET) with fluorodeoxyglucose (FDG) allows the visualization of metabolic tissue activity. Use of FDG in in-vivo cancer imaging is based on enhanced glycolysis in tumor cells. In vivo experiments have demonstrated the potential use of FDG PET in squamous-cell head and neck tumors and the detection of tumor involvement in lymph nodes. Since its introduction in this area, several papers have appeared on the use of this imaging modality. Indications for the use of FDG PET in patients with head and neck cancer are discussed. 相似文献
97.
J A Langendijk M K Tjwa J M de Jong G P ten Velde E F Wouters 《Radiotherapy and oncology》1998,49(2):175-183
BACKGROUND AND PURPOSE: This retrospective study was conducted to investigate whether endobronchial brachytherapy (EBB) is a risk factor for massive haemoptysis in patients primarily treated by a combination of EBB and external irradiation (XRT) for NSCLC. MATERIALS AND METHODS: The records of 938 patients with inoperable NSCLC who were treated with XRT and/or EBB were reviewed. The patients were divided into five groups as follows: group XRT, treated by XRT alone (n = 421); group XRTelig, treated by XRT but eligible for EBB (n = 419); group XRTEBB, primarily treated with EBB+XRT (n = 62); group EBBrec, treated by EBB for recurrence after XRT (n = 23); and group EBB, treated by EBB alone (n = 13). EBB was delivered using HDR. Patients with bronchoscopy-proven endobronchial tumour in the proximal airways, i.e. the trachea, the main bronchus or lobar bronchus were considered eligible for EBB. RESULTS: One hundred one out of 938 patients (10.8%) died from massive haemoptysis. The incidence was 4.3% in group XRT, 13.1% in group XRTelig and 25.4% in group XRTEBB. The differences between groups XRT and XRTelig as well as between groups XRTelig and XRTEBB were statistically significant (P<0.01). The incidence of massive haemoptysis depended significantly on the fraction size of brachytherapy. When two fractions of 7.5 Gy or a single fraction of 10 Gy were used, 11.1% of the patients died from massive haemoptysis. However, when a single dose of 15 Gy was used, 47.8% died from massive haemoptysis. In the multivariate analysis, a single dose of 15 Gy EBB was the most important prognostic factor for massive haemoptysis. CONCLUSION: XRT+EBB as primary treatment for NSCLC does not lead to a higher risk of massive haemoptysis as compared to XRT alone when fraction sizes for EBB of 7.5 or 10 Gy are used. However, the risk of massive haemoptysis increases dramatically when a fraction size of 15 Gy is used. 相似文献
98.
Human resources and access to maternal health care. 总被引:5,自引:0,他引:5
P ten Hoope-Bender J Liljestrand S MacDonagh 《International journal of gynaecology and obstetrics》2006,94(3):226-233
The lack of human resources is one of the main bottlenecks to achieving the Millennium Development Goals on maternal and child health. A coherent national policy, recognized across government, needs to be in place to overcome this especially in countries severely affected by HIV/AIDS. Such a policy should cover selection of pre-service students, the qualifications of trainers and training sites, supportive supervision, career path development, a package of carefully thought-out incentives for the retention of staff, strategies for interaction with communities, and an agreed-upon health staff HIV/AIDS policy. Without such coherent human resource planning, a large number of countries will fail to reduce maternal and newborn mortality. 相似文献
99.
De Hert SG Vander Linden PJ ten Broecke PW De Mulder PA Rodrigus IE Adriaensen HF 《Anesthesiology》2000,93(2):374-381
BACKGROUND: In a subset of coronary surgery patients, a transient increase in cardiac load by leg elevation resulted in a decrease in maximal rate of pressure development (dP/dtmax) and a major increase in end-diastolic pressure (EDP). This impairment of left ventricular (LV) function appeared to be related to a deficient length-dependent regulation of myocardial function. The present study investigated whether analysis of transmitral flow patterns with transesophageal echocardiography constituted a noninvasive method to identify these patients. METHODS: High-fidelity LV pressure tracings and transmitral flow signals were obtained in 50 coronary surgery patients during an increase in cardiac load by leg elevation. Using linear regression analysis, changes in transmitral E-wave velocity and deceleration time (DT) were related to changes in dP/dtmax and EDP. RESULTS: Changes in dP/dtmax with leg elevation were closely related to corresponding changes in E-wave velocity (r = 0.81; P < 0. 001) and to changes in DT (r = 0.78; P < 0.001). Similarly, changes in EDP were related to changes in E-wave velocity (r = 0.83; P < 0. 001) and to changes in DT (r = 0.84; P < 0.001). The decrease in dP/dtmax and the major increase in EDP in some patients was associated with an increase in E-wave velocity and a decrease in DT, indicating development of a restrictive LV filling pattern. CONCLUSIONS: Impairment of LV function with leg elevation was associated with the development of a restrictive transmitral filling pattern. Analysis of transmitral flow patterns by means of transesophageal echocardiography therefore allowed noninvasive identification of a subset of coronary surgery patients with impaired length-dependent regulation of LV function. 相似文献
100.
Preoperative evaluation of patients with primary head and neck cancer using dual-head 18fluorodeoxyglucose positron emission tomography 总被引:4,自引:0,他引:4
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OBJECTIVE: To evaluate the value of 18fluorodeoxyglucose (FDG) positron emission tomography (PET) in primary head and neck cancer. BACKGROUND DATA: Head and neck carcinomas tend to metastasize to regional lymph nodes rather than to spread hematogenously. With nodal metastases, cure rates decrease by approximately 50%. Moreover, in approximately 3% of the patients, a second primary tumor is found at initial presentation. METHODS: Fifty-four consecutive patients (31 men and 23 women; mean age 60 years, range 34-81 years) with previously untreated squamous cell carcinomas of the oral cavity or oropharynx were studied. Before surgery and within a period of 3 weeks, clinical examination, chest x-ray, computed tomography (CT), ultrasonography with fine-needle aspiration cytology (US/ FNAC), and FDG-PET were performed. All study results were scored per neck side and were also classified as 0 (no metastases), 1 (single metastasis), or 2 (multiple metastases). RESULTS: The sensitivity for the detection of lymph node metastases per neck side was 96%, 85%, and 64% for FDG-PET, CT, and US/FNAC, respectively. The specificity was 90%, 86%, and 100% for FDG-PET, CT, and US/FNAC, respectively. In terms of the classification, FDG-PET showed the best correlation with the histologic data. Finally, in nine patients (17%), a second primary tumor was detected by FDG-PET and confirmed by histologic evaluation. CONCLUSION: Because of the high prevalence of second primary tumors detected by FDG-PET and the decreased error rate in the assessment of lymph node involvement compared with CT and US, FDG-PET should be routinely performed in patients with primary head and neck cancer. 相似文献