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1.
Trypanosoma (Trypanozoon) brucei includes three morphologically identical subspecies which are poorly defined by clinical behaviour; T. b. brucei does not infect man, whereas T. b. rhodesiense causes an acute, and T. b gambiense a chronic, disease. Thirty-three isolates of the complex, each of which had previously been identified on clinical or other criteria, were compared by the electrophoretic patterns of two trypanosomal enzymes, alanine aminotransferase (ALAT) and aspartate aminotransferase (ASAT). One particular ALAT pattern clearly segregated a group of human pathogens of which all except one were labelled T. b. gambiense. The exception was labelled T. b. rhodesiense, and in addition three putative T. b. gambiense isolates did not have this pattern; it is suggested that only one presents a serious anomaly. The T. b. gambiense group could also be subdivided by three ASAT patterns which coincided with known groupings based on serological criteria.  相似文献   

2.
The protein composition of epididymal fluid and sperm extracts of rats treated with the nitroimidazole compound ornidazole was investigated by two-dimensional gel electrophoresis. Epididymal luminal fluid from the corpus and cauda regions of male animals rendered infertile by ornidazole treatment contained a prominent protein (contraception-associated protein 1, CAP1) with a molecular mass of approximately 25 kDa and an isoelectric point (pI) of 5.8; it was not found in fluids, but was present in sperm, from fertile vehicle-fed rats. Infrared matrix-assisted laser desorption/ionization mass spectrometry indicated that the molecular mass of CAP1 was 20420+/-120 daltons. Analysis of 17 amino acids demonstrated 49% homology to a diuretic hormone from an insect (Acheta domesticus). Densitometric quantitation of CAP1 on silver-stained gels indicated its presence in greater amounts in cauda than in corpus fluid from treated animals, whereas fluid from the rete testis lacked CAP1. In vitro incubations of tissue from the caput, corpus, and cauda epididymidal regions with [35S]methionine gave no hint that CAP1 was a secretion product of the epididymal epithelium. The absence of CAP1 from luminal fluid obtained from the sperm-depleted corpus epididymidis of efferent duct-ligated ornidazole-fed rats suggested a spermatozoal origin. CAP1 was present in spermatozoa from the caput epididymidis but not from the rete testis in control animals. Less CAP1 was present in detergent extracts of cauda sperm from ornidazole-treated rats than in sperm from control animals, suggesting a contraceptive-related displacement of protein from sperm to fluid. The association of ornidazole- and alpha-chlorohydrin-induced infertility with the presence of CAP1 in epididymal fluid, probably originating from spermatozoa, suggests a critical role for this protein in fertilization.  相似文献   

3.
BACKGROUND: Nitric oxide (NO), a recognized cell messenger for activating soluble guanylate cyclase, is produced by the enzyme NO synthase in a wide variety of tissues, including vascular endothelium and the central nervous system. The authors previously reported the possible involvement of the NO pathway in the anesthetic state by showing that a specific NO synthase inhibitor, nitroG-L-arginine methyl ester (L-NAME), dose dependently and reversibly decreases the minimum alveolar concentration (MAC) for halothane anesthesia. The availability of a structurally distinct inhibitor selective for the neuronal isoform of NO synthase, 7-nitro indazole (7-NI), allowed for the possibility of dissociating the central nervous system effects of neuronal NO synthase inhibition from the cardiovascular effects of endothelial NO synthase inhibition. METHODS: The effect of two structurally distinct inhibitors of NO synthase, L-NAME and 7-NI, on the MAC of isoflurane was investigated in Sprague-Dawley rats while concurrently monitoring the animals' arterial blood pressure and heart rate. L-NAME (1 to 30 mg/kg given intravenously, dissolved in 0.9% saline) and 7-NI (20 to 1,000 mg/kg given intraperitoneally, dissolved in arachis oil) were administered after determining control MAC and 30 min before determining MAC in the presence of NO synthase inhibitor. RESULTS: L-NAME and 7-NI caused a dose-dependent decrease from isoflurane control MAC (maximal effect: 35.5 +/- 2.5% and 43.0 +/- 1.7%, respectively) with a ceiling effect observed for both NO synthase inhibitors (above 10 mg/kg and 120 mg/kg, respectively). L-NAME administration significantly increased systolic and diastolic blood pressures (maximal effect: 39.9 +/- 2.2% and 64.3 +/- 4.0%, respectively), which were not accompanied by any changes in heart rate. 7-NI administration resulted in no changes in blood pressure and a small but clinically insignificant decrease in heart rate. CONCLUSIONS: Inhibition of the NO synthase pathway decreased the MAC for isoflurane, which suggests that inhibition of the NO pathway decreases the level of consciousness and augments sedation, analgesia, and anesthesia. The MAC reduction by two structurally distinct NO synthase inhibitors supports that this is a specific effect on NO synthase. Furthermore, the action of the neuronal NO synthase inhibitor 7-NI supports an effect selective for neuronal NO synthase and also avoids the hypertensive response of generalized NO synthase inhibitors.  相似文献   

4.
Based on the material of 24 human epididymides at ages 18 to 54, hemomicrocirculatory bed was studied of epididymis in man with the aid of a complex of morphologic techniques (injection of 20% Chinese ink-gelatine suspension, injection of a weak solution of caustic silver, transmission electron microscopy). It has been ascertained that architectonics and ultrastructural features of various links of the hemomicrocirculatory bed have signs of regional specificity for the subcapsular vascular network, small seminal ducts of caput epididymidis, ductus epididymidis of the head, body and tail of the organ. Reasons are discussed why specific hemomicrocirculatory bed should be caused to develop in different parts of the organ.  相似文献   

5.
A variety of sialic acids contained in the rat epididymis during post-natal development were examined by means of lectin and carbohydrate histochemistry. Epididymides from male Sprague-Dawley rats on post-natal days 14, 21, 30, 39, 49, 56 and 70 were fixed in Bouin's fluid and embedded routinely in paraffin wax. Hydrated sections were subjected either to the lectin methods using biotinylated Sambucus sieboldiana lectin or Maackia amurensis lectin or to the selective periodate oxidation-phenylhydrazine-thiocarbohydrazide-silver protein-physical development technique with or without saponification. The results revealed that sialic acids appeared in the epididymal epithelium at day 14, followed by particular distribution patterns corresponding to cell differentiation during days 21-39. High-level O-acetylation of sialic acids was observed in the principal cells of the initial segment and proximal caput after day 39. These results suggest that sialic acids with different linkages and O-acetylation become adult in distribution at the 'differentiation' period under the influence of androgen, before spermatozoa reach the epididymal lumen. Such carbohydrates may be correlated, at least in part, with sperm-binding sialoproteins, which increase dramatically during the window between days 21 and 39.  相似文献   

6.
We report a case of blastomycosis presenting as epididymitis and prostatitis. The diagnosis was suggested by pathologic findings in the prostate and epididymis and was further supported by serology. The diagnosis was confirmed by culture and special staining. Long-term cure was accomplished after a 12-month course of oral ketoconazole (400 mg/day). Therapy was monitored by culture and serology. Blastomycosis is an unusual but significant pathogen which occasionally presents with genitourinary tract involvement. Effective diagnostic and oral treatment regimens are now available but are dependent on a high degree of suspicion in cases of chronic prostatitis or epididymitis.  相似文献   

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The metabolism of 3H-testosterone by the epididymis and accessory organs of adult male rats exposed continuously to microdoses of cyproterone acetate from subcutaneous capsules were studied. The major metabolite of 3H-testosterone in the epididymis, vas deferens and ventral prostate of control rat was dihydrotestosterone while the formation of androstanediol by these tissues was low. The highest percentage of DHT was formed by the ventral prostate and cauda epididymis. In rats exposed to cyproterone acetate for four months, the conversion of testosterone to DHT was inhibited in all the tissues but maximally in the ventral prostate and cauda epididymis. In these rats, the secretory function of the ventral prostate was normal while that of the epididymis was markedly decreased. These data are discussed based on the differential thresholds of androgens required to regulate the functions of the accessory organs.  相似文献   

10.
Recent work on HIV counselling suggests that the protection of the moral status of the recipient is a key factor in the successful uptake of advice. This study suggests it may be equally important in the uptake of health promotion messages. A discourse analysis of the talk of 20 young injecting drug users (IDUs) identified a contradiction between their asserted self-identity as careful and socially responsible injectors, and their admission of risky lending and borrowing of injecting equipment. This contradiction was resolved by the production of discourses of exoneration, differentially tailored to the moral implications of lending and of borrowing. Lenders argued a form of 'market morality' wherein it was the duty of each to accept the consequences of his/her decisions. Lenders were therefore morally exonerated since moral failure was the 'borrowers'. Borrowing was usually depicted as 'desperate measures' for which moral culpability was disavowed because of 'powerlessness'. The exception of routine borrowing, acknowledged as risky and against community norms, was accounted for in a nihilistic discourse of indifference to infection and death. The need for a 'counter discourse' around notions of community is discussed.  相似文献   

11.
AIM: Although the relationship between the dose delivered to adjacent organs (urinary bladder and rectum) and the frequency and severity of treatment complications has been reported in many series, the factors influencing pelvic dose distribution are not well defined. The aim of the study was to assess retrospectively the influence of the size of cervical cancer brachytherapy applicators (ovoids and uterine tandems) on pelvic dose distribution and the impact of various therapy-dependent factors on patient anatomy and on dose distribution in particular applications. PATIENTS AND METHOD: The subject of this study were 356 cervical cancer patients treated with Selectron LDR as a part of their radical radiotherapy. Analysed factors included preceding external beam radiotherapy (EBRT) or brachytherapy applications, use of general anaesthesia for application and the system of pellet loading. RESULTS: Significant correlation was found between the size of applicators and doses to bladder, rectum and points B: larger vaginal applicators produced lower dose in bladder and rectum and higher dose in point B (all p < 0.0001), longer uterine tandems produced lower dose in rectum and higher dose in point B (both p < 0.0001). Significant decrease in the frequency of use of large applicators (ovoids: p < 0.0001, tandems: p = 0.055) and worsening of dose distribution, i.e. higher doses to critical organs (respectively: bladder p = 0.0012, rectum p = 0.02) and lower point B dose (p = 0.0001) were observed at consecutive brachytherapy applications. Similar situation occurred in patients, who received EBRT prior to brachytherapy (ovoids: p < 0.001, tandem: p = 0.04, bladder dose: p = 0.009, rectal dose: p = 0.073, point B dose: p = 0.059). Vaginal applicators were larger (p = 0.026) and the dose distribution was better (bladder: p = 0.023, rectum: p = 0.002, point B: p = 0.0001) in patients who had their insertions performed under general anaesthesia. The comparison of 2 consecutively used systems of pellet loading revealed more favourable dose distribution: lower dose for bladder (p = 0.014) and higher dose for point B (p < 0.0001) for the system, which utilised more sources in ovoids and in the distal part of the uterine tandem, in spite of more frequent use of smaller applicators in this group of patients. In multivariate analysis ovoid size was related to preceding external beam radiotherapy (p = 0.025). Uterine tandem length was dependent on the number of preceding intracavitary applications (p < 0.001) and preceding external beam radiotherapy (p = 0.007). Bladder dose was related to preceding brachytherapy (p = 0.011) and the pattern of pellet loading (p = 0.031). Rectal dose was dependent only on the use of general anaesthesia during application (p = 0.001) and point B dose was dependent on the pattern of pellet loading (p < 0.001) and marginally-on the use of preceding external beam radiotherapy (p = 0.06). CONCLUSIONS: The results of this study allow for identification of treatment-related factors determining pelvic dose distribution in cervical cancer brachytherapy and may potentially enable optimisation of this distribution in particular clinical situation.  相似文献   

12.
The presence and localization of glycerylphosphorylcholine (GPC) on the surface of human sperm, as well as the metabolism of its breakdown product L-glycerol 3 phosphate (G3P), were investigated. GPC was found to be associated with sperm after penetrating cervical mucus and was present after repeated washing of the sperm. GPC was partially released by treatment with 0.4 M NaCl in 0.01 M sodium phosphate buffer (pH 7.4) and localized to the head region after sperm fractionation. G3P did not increase O2 uptake of uncapacitated human sperm. However, under aerobic conditions, lactate accumulated when exogenous G3P or uterine GPC diesterase was added to sperm in suspension. The uptake of O2 by washed capacitated sperm pre-incubated with 1 unit of rat uterine GPC diesterase for 30 min was significant. This effect was inhibited by 2 microM oligomycin indicating that oxidative phosphorylation had occurred. The present study indicates that GPC may play a role in the metabolism of human sperm after capacitation.  相似文献   

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The authors describe a rare case of congenital cyst of cisterna ambiens treated surgically. Histological examination of cyst wall suggested that the cyst belonged to the group of developmental anomalies of the type of dysraphic intracranial cerebral herniae.  相似文献   

15.
The influence of pretreatment with the antihistaminic, mepyramine, or with the histamine liberator 48/80 was studied on the volume and the histamine content of pleural exudates induced in rats by intrapleural injection of turpentine, silver nitrate or carrageenan. The fluorometric determination of histamine was performed in the exudates collected at different times after injection of the irritant. In control animals the histamine levels were different from those previously found by the authors using biological assays. In rats pretreated with mepyramine or compound 48/80, the effects observed varied according to the nature of the irritant used to induce pleurisy.  相似文献   

16.
Autoradiographic study was conducted to localize 2-[125I]iodomelatonin binding in the rat epididymis. In the peripubertal (6 weeks old), postpubertal (8 weeks old) and adult (3 months old) rats, intense specific 2-[125I]iodomelatonin labelling of the corpus epididymidis was observed. The intensity of 2-[125I]iodomelatonin binding in the distal epididymal segment was significantly decreased in orchidectomized rats but the effect could be reversed with testosterone replacement. The intensity of 2-[125I]iodomelatonin binding in the distal rat epididymal segment did not show any diurnal rhythmicity when mid-light period and mid-dark period levels were compared, and was unaffected by constant lighting. Our data suggest androgen-dependent expression of 2-[125I]iodomelatonin binding sites, independent of light-induced changes in circulating melatonin, in the rat corpus epididymidis. A novel role of melatonin and its receptor in the regulation of the functions of rat corpus epididymidis is strongly implicated.  相似文献   

17.
OBJECTIVE: The purpose of the study was to evaluate the use of renal artery stents in the solitary functioning kidney of patients who have impaired renal function as a result of atherosclerotic renovascular disease by assessing primary patency, renal function outcome, and complication rates during a mean follow-up period of 15 months. MATERIALS AND METHODS: The Palmaz stent was placed in the arteries of 21 patients with solitary functioning kidneys. All patients had impaired renal function (creatinine level >150 micromol/l), and four patients were undergoing renal dialysis. Indications for stenting were recoil after percutaneous transluminal angioplasty (n = 12), arterial dissection after angioplasty (n = 2), restenosis after angioplasty (n = 1), and as the primary intervention (n = 6). Follow-up angiography was performed in 16 patients (76%). RESULTS: Initial technical success was achieved in all patients (residual stenosis, <5%). At follow-up (range, 6-25 months), renal function had returned to normal in five patients (24%), improved in four patients (19%), stabilized in six patients (29%), and deteriorated in six patients (29%). Dialysis has been discontinued in all four dialysis patients. Major complications occurred in four patients (19%), including one death within 30 days of stenting. No significant restenoses were seen on follow-up angiography. CONCLUSION: Placement of renal artery stents in the solitary kidney led to benefits in 70% of patients treated, including improved renal function in nine patients (43%) and stabilization in six patients (29%). In this high-risk group of patients, we advocate renal artery stenting as a relatively safe procedure to salvage the solitary kidney.  相似文献   

18.
孙涛  叶军  陈华珍 《黄金》2006,27(2):24-25
充填接顶是充填采矿法中重要的工艺环节。贯入式接顶充填充分利用了高浓度尾砂浆的性质,尾砂浆输送通过由地表到采场的高差而形成的流体静压力,挤压采场内的高浓度尾砂浆体,完成接顶充填。文中详述了贯入式接顶充填的技术要求和充填布置方案,与传统接顶充填相比,贯入式接顶充填具有工序简单、接顶效果好、成本低、安全程度高等优点,应用取得了很好的效果。  相似文献   

19.
Isolated hepatocytes from the rat were used to assess the maintenance of liver cell function in relation to the composition of the preservation medium. After separation by collagenase, they were incubated in Krebs-Ringer-Bicarbonate medium (KRB), Euro-Collins (EC), or University of Wisconsin (UW) solutions. Potassium influx, cell volume, and transaminase release were measured in cells freshly separated from control livers or from livers preserved in vitro up to 12 h in these media or having undergone orthotopic liver transplantation (OLT). While ion exchange levels were retained in all media, cells shrank significantly in UW but were able to restore their volume after 3 h of liver preservation. With regard to in vivo conditions, UW appears to be the best medium to prevent edema and to maintain more stable potassium exchange and enzyme production. These results are of value for liver transplantation in humans.  相似文献   

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