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31.
Catheters were developed that can be fixed in the prostate gland by self-expanding parts for use in PDR brachytherapy. Daily CT-scans were made to investigate the magnitude of catheter displacement. The mean absolute displacement during the 3 day treatment was 1.2 mm. The resulting minor alterations in dose-volume parameters were of no clinical importance.  相似文献   
32.
Cis-diammine dichloroplatinum (cisplatin) is an effective anticancerdrug which forms adducts with DNA, in both bacterial and mammaliancells. It is suspected of producing tumors as well. To determinethe molecular nature of geneti alterations induced by cisplatin,we cloned and sequenced cisplatin-induced mutants in the adeninephosphoribosyl-transferase (aprt) gene of Cinese hamster ovary(CHO) cells. Mutation by cisplatin appears to be targeted asthe sites of mutation are consistent with the known bindingspecificity of cisplatin. Many mutations occur at or proximalto the sequence 5'-AGG-3' and 5'-GAG-3' and include transversions,transitions, frameshifts and short deletions and duplications.Several double changes were also observed. No major rearrangementswere recovered in our collection. At several locations, a numberof mutants were found to be clustered within a small targetregion, but unlike traditional hotspots, tese represent diversechanges occurring in a localized region of a few base pairs.  相似文献   
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The morphological base for the impaired function of the blood retinal barrier was studied in 50 eyes of 10 insulin dependent and 21 non-insulin dependent patients with various levels of diabetic retinopathy. The permeability of the blood retinal barrier (PBRB) was determined by vitreous fluorophotometry with correction for autofluorescence, lenstransmission and non-protein bound plasma fluorescein concentration. Morphological abnormalities of diabetic retinopathy assessed by fundus photography and fluorescein angiography were individually scored on a decimal scale and related to the PBRB by multiple regression analysis. The Pbrb was not correlated to morphological abnormalities of non-proliferative retinopathy [(1) microaneurysms, (2) hard exudates, (3) soft exudates, (4) intraretinal hemorrhages, (5) fluorescein leakage, and (6) capillary closure, p > 0.3]. The PBRB was correlated to morphological abnormalities of (pre)proliferative retinopathy [(1) intraretinal microvascular abnormalities (Sirma) and (2) new vessels (Sneo): pbrb = A – B.SIRMA – C.Sneo with PBRB in nm/sec, A = 1.5 ± 0.5, B = 0.9 ± 0.2 and C = 1.7 ± 0.4, R2 = 0.65, p < 0.0001]. It can be concluded that the increased blood retinal barrier permeability in diabetic patients is mainly due to (pre)proliferative abnormalities and not to non-proliferative abnormalities.  相似文献   
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Chronic allograft nephropathy (CAN) of renal allografts is still the most important cause of graft loss. A subset of these patients have transplant glomerulopathy (TGP), characterized by glomerular basement membrane (GBM) duplications, but of unknown etiology. Recently, a role for the immune system in the pathogenesis of TGP has been suggested. In 11 of 16 patients with TGP and in 3 of 16 controls with CAN in the absence of TGP we demonstrate circulating antibodies reactive with GBM isolates. The presence of anti-GBM antibodies was associated with the number of rejection episodes prior to diagnosis of TGP. Sera from the TGP patients also reacted with highly purified GBM heparan sulphate proteoglycans (HSPG). Indirect immunofluorescence with patient IgG showed a GBM-like staining pattern and colocalization with the HSPGs perlecan and especially agrin. Using patient IgG, we affinity purified the antigen and identified it as agrin. Reactivity with agrin was found in 7 of 16 (44%) of patients with TGP and in 7 of 11 (64%) patients with anti-GBM reactivity. In conclusion, we have identified a humoral response against the GBM-HSPG agrin in patients with TGP, which may play a role in the pathogenesis of TGP.  相似文献   
37.
We are grateful to Dr Parmar for raising this important issue.Dr Parmar appears to be under the impression that our studysample consisted of elderly men with hypertension.  相似文献   
38.
The use of highly active antiretroviral therapy (HAART) in the management of human immunodeficiency virus (HIV) infection has resulted paradoxically in the worsening of clinical symptoms of previously subclinical infections, such as herpes zoster (HZ), herpes simplex, angular cheilitis, warts, tuberculosis, hepatitis B and C, cytomegalovirus retinitis, and others, as a result of substantial reconstitution of the host's immune responses. This phenomenon is referred to as immune reconstitution inflammatory syndrome (IRIS). It may affect up to 32% of HIV-seropositive subjects within a wide range of time after the initiation of HAART, but mainly after 8-12 weeks. Mucocutaneous HZ accounts for 7%-12% of the diseases associated with HIV infection that become worse again when the subject's immunity improves from the administration of HAART. It usually occurs after 4 weeks from the initiation of HAART, and under these circumstances the clinical symptoms and natural course of mucocutaneous HZ are similar to those in HIV-seropositive subjects who do not manifest IRIS.  相似文献   
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Screw-fixated and hydroxyapatite-coated press-fit cups were studied using radiostereometry in 29 revision and 14 primary arthroplasties. The acetabular defects in the revision cases varied from none to type 3 (wall defects) according to Gustilo—Pasternak. Morsellized allograft was used in 25 revisions. Nine of these cups rested on less than 50% living bone. After 2 years, the mean migration in the revised group reached 0.36, 0.21, and 0.49 mm in the horizontal, longitudinal, and anteroposterior (AP) directions. The mean rotations varied between 0.5° and 0.7° depending on direction. The primary implants displayed smaller mediolateral migration and AP tilt. The mean proximal wear rate for the whole group was 0.11 mm/y. A central gap on the postoperative AP view implied less migration. The size of the preoperative bone defects or amount of bone—graft used had no influence on the migration. Despite extensive use of morsellized allograft, this implant displayed the smallest migration so far reported in revision hip arthroplasty.  相似文献   
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