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1.
We studied the parathyroid function in patients with advanced renal failure by determining their plasma concentrations of ionized calcium (iCa), intact parathyroid hormone (PTH) and its inactive metabolites (PTH-MM). The suppressibility of the parathyroidism was studied with a calcium infusion test. The intact PTH values of the nondialysis and dialysis patients did not statistically differ from each other. The concentrations of PTH-MM were, however, higher in the dialysis patients than in the nondialysis patients (p less than 0.05). The ratio of PTH-MM to intact PTH was lowest in healthy reference subjects and highest in dialysis patients (p less than 0.01), and did not correlate with the degree of intact PTH elevation in the patient groups. The calcium infusion test was carried out on 15 patients. All showed suppression in the elevated plasma intact PTH concentration and in 6 the intact PTH value normalized. The PTH-MM value did not normalize in any of the patients. During oral calcium treatment the degree of intact PTH suppression at an achieved concentration of plasma iCa was predictable from the infusion test. Three patients were parathyroidectomized after the calcium infusion test. In 2 of these elevated intact PTH normalized within 24 h while in 1 no change took place. In this latter case on clinical improvement was noted. We conclude that the determination of plasma intact PTH concentration especially of combined with plasma iCa value is a reliable means of studying the hyperparathyroidism associated with chronic renal failure.  相似文献   
2.
The diagnostic significance of anticytoplasmic autoantibodies (ANCA) was studied in 71 renal patients. The ANCA test was positive in 67% of patients with Wegener's granulomatosis (WG), in 35% of those with a simultaneous renal and respiratory tract disease but not diagnosed as WG and in 22% of patients with a renal disease associated with unspecific collagenosis/vasculitis. Among WG patients ANCA positivity clearly correlated with the presence of active renal disease. Interestingly, both ANCA-positive and -negative patients were encountered in the group with acute renal failure and acute extracapillary glomerulonephritis associated with diffuse pulmonary infiltrates. The diagnostic and clinical significance of the ANCA test in these cases remains for the present obscure. In the majority of the ANCA-positive renal patients with respiratory tract abnormalities, the antibodies showed diffuse cytoplasmic staining and were mostly of the IgG class, of both IgG and IgM classes in some cases and of IgG, IgM and IgA classes in 1 patient. In patients with unspecific vasculitis/collagenosis the level of ANCA was rather low, and the distribution of different isotypes resembled that of patients with respiratory symptoms. A certain isotype of ANCA or staining pattern did not mark out any clinicopathologic subgroup among the patients. Our findings indicate that the clinical picture of ANCA-positive patients varies considerably and the ANCA test may not be as specific a marker of WG as previously suggested.  相似文献   
3.
The induction of hepatic peroxisome proliferation and drug metabolizing enzymes and of sister chromatid exchange (SCE) in lymphocytes was studied in male Han/Wistar rats after exposing them for 2 weeks to a commercial chlorophenolate formulation (Ky-5) (100mg/kg/ day), to 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD; 0.05–5 g/kg/wk) and to the pure phenoxyacetic acids, 2,4-dichlorophenoxyacetic acid (2,4-D; 100 mg/kg/day) and 2-chloro-4-methylphenoxyacetic acid (MCPA; 100 mg/kg/day). The chlorophenolate formulation and pure 2,4-D and MCPA caused significant increases in the number of peroxisomes in liver cells, although the average size of peroxisomes was not affected, whereas the effect of even the highest dose of 2,3,7,8-TCDD remained small. This finding indicates that dioxin impurities do not account for the peroxisome proliferation induced by chlorophenolate. The relative weight of the liver increased significantly in rats treated with the chlorophenolate formulation and with 2,3,7,8-TCDD (5.0 and 0.5 g/kg). The pattern of induction of xenobiotic metabolizing enzymes showed some differences between chlorophenolate treatment and 2,3,7,8-TCDD treatment. Furthermore, the effects of pure phenoxyacetic acids were different from that seen with chlorophenolate and 2,3,7,8-TCDD. The highest dose of 2,3,7,8-TCDD increased the frequency of SCE in circulating lymphocytes slightly, but significantly.  相似文献   
4.
Of the families who had received genetic counselling between 1972 and 1981, 791 replied to a questionnaire which covered recall of information, post-counselling reproduction and attitudes towards counselling and prenatal diagnosis. Eighty percent had adequate knowledge of mode of inheritance and 74% of recurrence risk. Knowledge of mode of inheritance was poorest in multifactorial transmission (63%) and knowledge of recurrence risk in X-chromosomal disorders (61%). Forty-five per cent of the families had started a pregnancy after the counselling. 25%). Early lethality of the disorder and feasibility of a prenatal study contributed to positive reproductive decisions. Nine per cent of the children born after the counselling were affected by the disorder in question. The observed risks tended to match well with the expected ones. Sixty-two per cent of the respondents felt that the counselling had had a great or moderate impact on their reproductive plans. Forty-two per cent expressed a wish to hear the counsellor's opinion in addition to the facts. This was more common when the disorder was severe. Although most couples (53%) wished to have a prenatal study, if feasible, and abort an affected foetus, 16% were against abortion in such a case and 31% wished to have the study but were ambiguous about an abortion.  相似文献   
5.
Summary: Non-invasive monitoring of adaptive immunity in infection, cancer, and autoimmunity remains a major challenge. Current techniques to monitor lymphocytes involve numeric and functional determinations of immune cells isolated from the peripheral blood (most often) and tissue (rarely). Invasive measurements are prone to sampling errors and are poorly reflective of the dynamic changes in the location, number, and movement of lymphoid cells. These limitations indicate the need for non-invasive whole-body imaging methodologies that allow longitudinal, quantitative, and functional analyses of the immune system in vivo . Positron emission tomography (PET), a clinically based whole-body imaging modality, has the potential to revolutionize diagnostics and therapeutic monitoring in both clinical and pre-clinical settings. This review discusses studies using PET to image adaptive immune responses in small animal models. We address the challenges inherent in assessing whole-body immunity with PET and recent developments that can improve its performance. Finally, we discuss work to translate PET immune imaging into clinical practice.  相似文献   
6.
PURPOSE: We assess the effect of finasteride, a 5alpha-reductase inhibitor, on objective voiding parameters in men with lower urinary tract symptoms and benign prostatic enlargement on digital rectal examination (known as clinical benign prostatic enlargement) in a double-blind placebo controlled multicenter study using strict standard pressure flow study techniques. MATERIALS AND METHODS: A modification of the Abrams-Griffiths nomogram was used by 1 reader to ensure that all patients met objective criteria for bladder outlet obstruction at baseline. After performing a pressure flow study patients with obstruction were randomized 2:1 to receive 5 mg. finasteride (81) or placebo (40) daily. A second pressure flow study was performed at month 12. At baseline and month 12 free urinary flow studies and transrectal ultrasound were performed, and International Prostate Symptom Score questionnaires were completed. Patients were treated between May 1994 and July 1996. RESULTS: Finasteride caused a significant decrease (-8.1 cm. water) in detrusor pressure at maximum flow (p <0.05 versus placebo p = 0.02), increase (+1.1 ml. per second) in maximum flow rate (p <0.05 versus placebo p = 0.02) and decrease (-22.8%) in prostate volume (p <0.05 versus placebo p <0.001). Men with prostates larger than 40 cc had greater improvement in detrusor pressure at maximum flow (between group difference -14.5 cm. water, 95% confidence interval -26.2 to -2.6, p = 0.02) and maximum flow rate (mean treatment effect +1.6 ml. per second, 95% confidence interval -0.2 to 3.0, p = 0.02) compared to those with prostates 40 cc or less (between group differences not significant). CONCLUSIONS: Finasteride treatment resulted in improvements in urodynamic parameters, which were greater in men with large prostates.  相似文献   
7.
Zusammenfassung Nach 4- und 12wöchiger Implantation in der Rückenmuskulatur von 6 Monate alten gleichgewichtigen männlichen Kaninchen sowie nach ein- bis viermaligem Autoklavieren erfolgte die Untersuchung von standardisierten Probekörpern aus Polyacetalharz (Polyoxymethylen-Copolymer), Polyester (Polyäthylenterephthalat), Polyäthylen und Teflon (Polytetrafluoräthylen) im Rahmen eines Zugversuches. Dabei zeigte es sich, daß Polyester durch Implantation und Autoklavieren eine starke Verminderung der viscoelastischen Eigenschaften erfährt. Während Polyäthylen und Teflon nach beiden Behandlungen im wesentlichen unveränderte Eigenschaften aufweisen, läßt sich bei Polyacetalharz nach 12wöchiger Implantation und viermaligem Autoklavieren nur eine leichte Verminderung der viscoelastischen Eigenschaften im Sinne einer Versprödung von 10 bis 15% nachweisen.Die histologisch-qualitative Beurteilung des umliegenden Gewebes ergibt eine überragende Gewebsverträglichkeit von Polyäthylen, während bei den drei übrigen Kunststoffen Polyacetalharz, Polyester und Teflon eine vergleichbare Fremdkörperreaktion nach 4 Wochen erkennbar ist, die nach 12 Wochen jedoch deutlich abgenommen hat.
The change of physical properties of plastics (polyoxymethylenecopolymer, polyethyleneterephthalate, polyethylene, polytetrafluorethylene) after animal implantation and autoclavation
Summary The change of physical properties of plastics (polyoxymethylene-copolymer, polyethyleneterephthalate, polyethylene, polytetrafluorethylene) and the bio-compatibility of these materials were examined by implantation in the backmuscle of 6-month-old male rabbits for 4 and 12 weeks and after autoclavation.We have found out, that after implantation and autoclavation polyethyleneterephthalate demonstrates a strong diminution of the visco-elastic qualities. Polyethylene and polytetrafluorethylene were not changed by these treatments. After an implantation of 12 weeks and an autoclavation of four times the visco-elastic properties of polyoxymethylene-copolymer were only slightly diminished by 10 to 15%.The histological investigation of the surrounding tissue demonstrated a very good bio-compatibility of polyethylene. After an implantation of 4 weeks polyoxymethylene-copolymer, polyethyleneterephthalate and polytetrafluorethylene produced a comparable foreign body reaction, which, however, was evidently diminished after an implantation of 12 weeks.


Mit Unterstützung der DFG (Schwerpunkt Biopolymere und Biomechanik von Bindegewebssystemen).

Für Beratung und Unterstützung danken wir Herrn Prof. Dr. H. Ueberberg, Biberach, Abteilung für Experimentelle Pathologie der Firma Dr. K. Thomae.  相似文献   
8.
Renal findings and glomerular pathology in diabetic subjects   总被引:3,自引:0,他引:3  
BACKGROUND: To describe the relationship between proteinuria, hematuria, and renal insufficiency, on one hand, and glomerular pathology, on the other hand, in a consecutive biopsy series of diabetic patients. SUBJECTS AND METHODS: All diabetic subjects (n = 200) biopsied from 1979 to 1995 at Tampere University Hospital were identified in retrospect. The clinician-based indication (any unexplained renal finding) for renal biopsy was consistent during the years and was: proteinuria alone in 68%; combined with hematuria in 10%; with renal insufficiency in 10%; with both in 9%, and with isolated hematuria or renal failure in 3%. One third of the subjects had proteinuria of >/=3 g/24 h and 16% a serum creatinine level of >/=200 microM. Glomerulopathy was found in 171 specimens and defined as nodular diabetic (group A), diffuse diabetic (group B) and primary (group C). The 24-hour urinary protein excretion rate [mean (range)] was 3.5 (1.6-6.9), 1.0 (0.5-3.5), and 3.6 (1.1-6.6) g in groups A, B and C, respectively (ANOVA p = 0.001). The corresponding serum creatinine values [mean (SD)] were 175 (115), 105 (142) and 169 (138) microM (p = 0.001). Results: Nodular diabetic glomerulopathy was found in 40%, diffuse diabetic glomerulopathy in 42% and primary glomerulopathy in 18%. A primary glomerulopathy was found in any indication and in both types of diabetes (prevalence range 14-26%). The best multivariate logistic regression model obtained (chi(2) = 13.5, p = 0.008) in predicting the presence of diabetic glomerulosclerosis (group A + B) in contrast to a primary glomerulopathy (group C) included retinopathy (p = 0.04), renal insufficiency (p = 0.03), hematuria (p = 0.12) and type of diabetes (p = 0.10). CONCLUSION: In this series of diabetic subjects, biopsied due to proteinuria, hematuria and not severe renal insufficiency, 18% had evidence of a primary glomerulopathy.  相似文献   
9.
Four neonates with convulsions had IgG antibodies in their cerebrospinal fluid (CSF) to varicella zoster virus (VZV). These antibodies were found in the sera of two of these patients after the age of 6 months. Antibodies to 16 different microbes were studied from the serum and CSF of 201 neonates with neurological problems. The presence of DNA specific to HSV-1, HSV-2, and VZV in the CSF was also investigated using the polymerase chain reaction (PCR). Antibodies to VZV were detected in the CSF of four neonates. Antibody indices suggested production of VZV specific antibodies in the central nervous system. These findings suggest that intrathecal production of antibodies to VZV can appear in neonates with neurological problems, which suggests that intrauterine VZV infection can be acquired without cutaneous symptoms in the mother.  相似文献   
10.
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