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71.
Summary The proportional area of each renal arterial segment was analyzed in 49 polyester resin corrosion endocasts of the renal vasculature. We defined a segmental artery as a primary or secondary branch of the renal artery that could be isolated outside the hilum. We found kidneys with five arterial segments in 30 of 49 casts (61.2% of cases) and kidneys with four arterial segments in 19 of 49 casts (38.8%). To enable the evaluation of the proportional areas of the autonomous segments (by using the point-counting planimetry method), each arterial segmental branch was injected with different-colored resin. The superior segment (apical) was present in 36 of 49 casts (73.5% of cases) and had a median proportional area of 13.02%. The anterosuperior and anteroinferior segments were present in 30 of 40 casts (61.2% of cases) and had median proportional areas of 21.36% and 17.18%, respectively. The anterior segment was present in 19 of 49 casts (38.8% of cases; when the mid-kidney anterior surface received only one segmental artery) and had a median proportional area of 28.44%. The inferior segment was present in 100% of cases and had a median proportional area of 22.65%. The posterior segment was also present in 100% of cases and was the segment with the greatest median proportional area (33.76%). 相似文献
72.
K. R. Clark J. L. R. Forsythe B. K. Shenton T. W. J. Lennard G. Proud R. M. R. Taylor 《Transplant international》1993,6(1):18-21
In renal transplantation, treatment of steroid-resistant rejection (SRR) with antithymocyte globulin (ATG) has been widely reported but over-immunosuppression remains a common problem. In the first ten patients (group 1) treated for SRR with rabbit ATG, three developed serious viral infections and two deaths occurred due to CMV pneumonitis. ATG was only omitted if thrombocytopenia or neutropenia occurred. In the next 17 patients (group 2) with SRR, ATG was administered according to the absolute T lymphocyte count. T lymphocytes were measured by flow cytometric analysis of CD3-labelled lymphocytes. ATG dosage was adjusted on a daily basis to keep the absolute T lymphocyte count under 50 cells/l. Administration of ATG according to the absolute T lymphocyte count resulted in a significant reduction in the mean dose of ATG given to the group 2 patients (P<0.001). A significant decrease in the incidence of serious viral infections (P=0.04) was achieved without reducing the ability of ATG to reverse the SRR (P=0.29) or increasing the number of grafts lost at 1 year in the group 2 patients (P=0.23). 相似文献
73.
The Effects of Permeation Enhancers on the Surface Morphology of the Rat Nasal Mucosa: A Scanning Electron Microscopy Study 总被引:2,自引:0,他引:2
A rat model has been developed to compare relative morphological changes in the nasal mucosa after exposure to potential membrane permeation enhancers. Scanning electron microscopy was used to characterize gross structural and specific cellular changes following exposure. Micrographs of the rat nasal mucosa were scored in four categories: (1) mucosal surface integrity, (2) ciliary morphology, (3) mucus/extracellular debris, and (4) presence of red blood cells. The order of increasing morphological damage resulting from a 5-min exposure to each surfactant was 0.5% Solulan C-24 0.5% Solulan C-24/0.5% sodium tauro-24,25-dihydrofusidate (STDHF) < 0.5% STDHF < 1.0% STDHF 1.0% Laureth-9 < 1.0% sodium taurodeoxycholate 1.0% sodium deoxycholate. The changes observed in the mucosal morphology after exposure to the various surfactants are in general agreement with data in the literature. This model is able to compare rapidly the relative morphological effects on the mucosal membrane of different nasal formulations. 相似文献
74.
Nine sawmill workers were divided into two groups according to their exposure to 2-ethylhexanoic acid, (EHA), a pesticide which has replaced the older pentochlorophenol. The men with lower exposure excreted 30±10 nmol EHA/mmol creatinine (mean ±SD,n=4) in urine samples taken after the workshift, whereas men with higher exposure excreted 1.8±1.6 mol EHA/mmol creatinine (mean±SD,n=5,p<0.01). The urinary ornithine and arginine concentrations were at the lower exposure 1.4±0.4 and 1.5±0.8 mol/mmol creatinine, respectively (mean±SD,n=4), and they increased significantly (p<0.01) to 4.5±2.5 and 3.2±1.5mol/mmol (mean±SD,n=5), respectively, at the higher exposure. This might have been caused by the inhibitory effect of EHA on urea synthesis which was partially compensated for by elevated arginine and ornithine concentrations to drive the urea cycle more efficiently. 相似文献
75.
Omoto M Imai T Seki K Nomura R Otahara Y 《Environmental health and preventive medicine》1997,2(3):105-116
Based on the fact that chemical products such as binding agents are produced by mixing three kinds of phosphates with different
ratios, we mixed metaphosphate, polyphosphate and pyrophosphate. Each was made to Na-phosphate, K-phosphate, and Ca-phosphate
and each was mixed with commercial feeds so that the content of P would be approximately 0.1, 0.15, 0.3, 0.4, 0.6 and 1.0%.
The prepared pellets were given to ICR, CF # 1 and AKR strains of mice at 29 days of age for 680 days and observations were
made through this experimental period at different stages. The observations were also carried out on the mice administered
with the experimental feeds for 1.5 months from 9 to 10.5 months of age. The observations were compared with those of the
control group at all times. As a result, plasma 1 α, 25 (OH)2 D3 and P levels were always significantly higher in the phosphate administered groups relative to the control. Urine P and Fe
increased while urine Ca decreased in the phosphate-treated groups.
The effect of phosphates on the bones was studied taking soft X-ray pictures of hind legs and applying microdensitometry to
them. Through these observations we recognized thinning of the cortex of bones, reduction of marrow trabecules and development
of osteophyte. Histological observations disclosed that changes in knee joint tissues were apparent; that is, a decrease in
or an irregular loss of the number of cells in superficial, intermediate, and radial strata of the joint cartilage, proliferation
of subchondral bone, and the development of osteophytes were noted. As for muscles, diameters of musclar fibers became smaller;
in particular, type II fibers showed greater shrinkage. Regarding kidneys, swelling and atrophy of glomerular capillaries,
proliferation of mesangial cells, nephroselerosis, swelling, thinning, and loss of tubular epithelium, interstitial tissue
inflammation, development of cylindruria, and deposition of calcium were observed. All these changes seem to be a particularly
advanced aspect of the changes which are more pronounced with increasing dose and age.
These changes were found even in the group administered with the feed containing 0.1% phosphorus, and, these changes were
dependent on the concentration level of P. It was observed that administration to older subjects for a short term (1.5 months)
produced effects stronger than those to younger subjects administered for a long term (10.5 months).
The effects of condensed Ca-phosphate on bones were similar to those of condensed Na- and K-phosphates, and, hence, it was
supposed that these effects were caused by phosphate radicals.
An erratum to this article is available at . 相似文献
76.
We compared the effect of orally administered 100 mg of hydrochlorothiazide (HCTZ) among eight patients with pseudohypoparathyroidism (PHP) type I, 11 patients with idiopathic hypoparathyroidism (IHP), and 12 patients with primary hyperparathyroidism (1oHPT). Patients with PHP type I or with IHP were studied during the treatment with 1-hydroxylated metabolites of vitamin D3. HCTZ raised serum levels of calcium (Ca) in 1oHPT (P<0.001) and PHP type I (P<0.01) but did not increase urinary excretion of Ca. Serum parathyroid hormone (PTH) in PHP type I decreased (P<0.02) after HCTZ administration in response to the increase in serum Ca. HCTZ did not raise serum levels of Ca in IHP but increased urinary excretion of Ca in this group (P<0.01). HCTZ suppressed tubular reabsorption of phosphate (P) in IHP (P<0.01) and 1oHPT (P<0.05) but not in PHP type I. Urinary excretion of cAMP did not change after HCTZ administration in PHP type I, IHP, or 1oHPT. Endogenous PTH modulated the effects of HCTZ on Ca mobilization from bone and renal reabsorption of Ca in PHP type I with normal or high serum levels of PTH and in 1oHPT with high serum levels of PTH. The inhibitory effect of HCTZ on renal tubular reabsorption of P (probably from proximal tubules) was independent of PTH. The resistance to this inhibitory effect of HCTZ on P reabsorption in PHP type I suggested a proximal tubular dysfunction in this disorder. 相似文献
77.
A review entitled “The human toxicity of marijuana” was published in 1992 in the Medical Journal of Australia. The authors claimed that the adverse effects of cannabis use have been trivialized and that the effects are much more serious than earlier reported. We have made a careful study of this review and examined the claims made. We compared the claims of the authors with the information contained in the documents they cited and found that at least 28 of the 35 citations in this article were cited inaccurately. Five of these publications were misquoted, or the findings of the study were not fully reported. Twenty-three citations contained other errors, leaving only six to eight (two citations could not be retrieved because of their obscurity) accurate citations among 35. All of these inaccuracies operate in the direction of finding an adverse effect of marijuana. 相似文献
78.
Masato Kochi Shuichi Takaki Jun -ichi Kuratsu Hiroshi Seto Isao Kitamura Yukitaka Ushio 《Journal of neuro-oncology》1994,19(3):239-244
Summary Ventriculolumbar perfusion of methyl 6-[3-(2-chloroethyl)-3-nitrosoureido]-6-deoxy-alpha-D-glucopyranoside (MCNU), a water soluble nitrosourea with log P-0.71, may be efficacious in the treatment of subarachnoid dissemination of malignant glioma. We used 2 dogs to study the neurotoxicity and pharmacokinetics of MCNU. MCNU (1 mg), dissolved in 10 ml of artificial CSF, was administered via the right lateral ventricle during a period of 18 to 42 min and the CSF was drained by lumbar puncture. The perfusion was repeated once a week for 10 consecutive weeks. No neurological and systemic symptoms were noted after perfusion. Histological examination of the brain and spinal cord showed local denudation of the ependyma and local subependymal spongy degeneration and gliosis in the lateral ventricle into which MCNU was administered in one dog and local denudation of the ependyma in the other. When administration was over a period of 21 to 38 min, the MCNU concentration in the lumbar CSF peaked at 11.11 to 50.67 g/ml, in 28 to 78 min. The area under the drug concentration-time curve (AUC) was 1152 g×min/ml on average, significantly larger than that of ACNU. The elimination phase followed linear kinetics and the half-time was 41.1 min on average, significantly longer than that of ACNU. These findings suggest that ventriculolumbar perfusion of MCNU may be effective in the treatment of subarachnoid dissemination of malignant glioma notwithstanding some local histological changes. 相似文献
79.
Mohsen Shahsavari Gholam A. Peyman Michael R. Niesman Michael V. Miceli Jesse Jaynes 《International ophthalmology》1995,19(1):29-34
An investigation was undertaken to determine the toxicity of an intravitreal injection of a novel peptide drug, Shiva-1, in rabbits. The drug, a synthetic peptide modeled after lytic peptides secreted by certain insects, has antiproliferative and antibacterial properties. Initial in vitro experiments showed that the drug, at a concentration of 100 M, was toxic to both Y-79 retinoblastoma cells and human retinal pigment epithelial cells. A wide range of doses (6–1200 g) was injected into the rabbit vitreous in an attempt to determine the maximum tolerated dose. Retinal toxicity was evaluated clinically, by electroretinography, and by light microscopy. Some localized toxicity was evident at 200 g; all doses of 240 g and above were toxic. While the drug appears to exhibit a narrow range between effective and toxic doses, the results suggest that this and other peptides of similar design merit further investigation for the treatment of proliferative and infectious diseases of the eye.Supported in part by U.S. Public Health Service grants EY07541 and EY02377 from the National Eye Institute, the National Institutes of Health Services, Bethesda, MD, USA 相似文献
80.