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1.
Susceptibility of mink to intoxication by aflatoxins was studied by giving mink single doses (300, 600, and 900 mug of aflatoxins B1 and G1 (40:60)/kg of body weight) and observing them for 8 weeks. One, 2, and 4 of 5 mink in each group died within 4 days after ingesting the small, medium, and large doses, respectively. Enlarged liver with pale yellow to yellowish pink spots was the most consistent lesion observed in mink that died of acute aflatoxicosis. Some lobules of liver also appeared hemorrhagic and fragile, whereas others showed fatty metamorphosis. Histopathologic examination of the liver showed different degrees of fat infiltration, bile duct proliferation, and necrosis of liver cells. Hematologically, mink that survived were not appreciably different from control mink in terms of hemoglobin content, packed cell volume, and white blood cell count. Liver specimen from aflatoxin-treated mink contained more fat, was larger, and contained less protein, RNA and DNA than did liver from control mink. Aflatoxin residue (only B1 ) was recovered from liver of 6 mink and were between 0.1 and 7.6 mug of the original dose.  相似文献   

2.
A method for investigating the humoral immune response in mink (Mustela vison) was developed between October 1993 and March 1994. Protein A, 1:8000 dilution, had a high affinity for mink immunoglobulin, while anti-ferret (Mustela putorius) antibody, 1:200 dilution, had a weaker affinity. Four adult mink were immunized with a hapten, dinitrophenol (DNP), conjugated to a large carrier protein, keyhole limpet hemocyanin (KLH), and received two boosters at 3-week intervals. This provoked a strong T-lymphocyte dependent humoral immune response. An indirect enzyme linked immunosorbent assay (ELISA) was used to quantify the antibody produced. All mink had undetectable anti-DNP-KLH antibody in the pre-immune sera, with antibody levels increasing post-immunization, and peaking after the first or second booster.  相似文献   

3.
The purpose of the present study was to determine whether the blood barrier of the epididymis and vas deferens acted synchronously or not with the blood barrier of the testis. The permeability of the blood-epididymis and blood-vas deferens barrier was tested in neonatal kit mink up to puberty and monthly in adult minks throughout the annual seasonal reproductive cycle. Attention was focused particularly on time intervals when the blood barrier of the testis has been documented to be permeable, namely, before puberty and during testicular regression in the adult. One of two electron-opaque permeability tracers was perfused into the blood stream: horseradish peroxidase (HRP) or lanthanum nitrate. The convoluted tube of the epididymis was divided into three anatomical regions: the caput, corpus, and cauda. The vas deferens was divided into proximal and distal regions. At birth and throughout puberty, the three regions of the epididymis and the two of the vas deferens showed a lumen and a competent blood barrier. In the adult, a lumen persisted in the epididymis and vas deferens throughout the annual seasonal reproductive cycle, and the blood barrier of the excurrent duct remained impermeable even when the blood barrier in the testis became momentarily permeable during testicular regression. When HRP was used to test the permeability of the blood-tissue barrier of the excurrent ducts, no tracer deposits were observed on the lumenal surface of the epithelium. Conversely, when lanthanum served as the tracer, deposits of the probe were associated with microvilli and intracellular membranes despite impermeability of tight junctions. The data show that the lanthanum technique can yield false-positive results. The findings also indicate that 1) a blood-excurrent duct barrier is established before the blood-testis barrier and 2) the two barriers act asynchronously. It is therefore plausible that they are modulated by distinct factors.  相似文献   

4.
Two feeding trials were done to study the susceptibility of mink (Mustela vison) to multiple sublethal doses of aflatoxins. In the 1st trial, twenty 3-month-old male mink were divided equally among groups. Each mink in groups 1, 2, 3, and 4 was given a meatball daily that contained 15, 30, 45, or 0 mug of aflatoxins (B1:G1, 40:60), respectively. All mink in group 3 died between the 25th and the 30th days of the feeding trial. Each mink had ingested 1,035 to 1,480 mug of aflatoxins. Four of the mink in group 2 died almost as soon as did mink in group 3. Four mink in group 1 died between 40 and 59 days after the start of the feeding trial. Generally, a marked increase in plasma cholesterol and alkaline phosphatase activity appeared before mink died. The liver from animals that died of aflatoxicosis showed prominent pathologic changes which included hemorrhages and appearance of pink yellow spots. Histopathologic examination of liver from dead mink revealed fatty infiltration, bile duct proliferation, bile stasis, pseudotubular formation, congestion, and fibrosis. The feeding trial was repeated with 20 mink (8 males and 12 females) that were 1.5 to 2 years old. In this instance, 0, 20, 40, and 60 mug of aflatoxins were administered each day. All treated animals, except 1, were dead within 37 days after the experiment started. The survivor was given the lowest dosage of toxins and died after 52 days by which time 960 mug of aflatoxins were consumed. Plasma cholesterol content and alkaline phosphatase activity generally were similar to those observed in younger mink of the 1st feeding trial.  相似文献   

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In a five-generation selection experiment, separate lines of standard mink (Mustela vison) were subjected to selection for litter size at 3 wk (F line), body weight in September (BS line), underfur density (P line), or combined selection for litter size and body weight (I line). One unselected line served as a control (C line). The present paper focuses on correlated responses to selection regarding fertility and fitness traits, fur quality, and body size traits. Genetic and environmental parameters were estimated with REML (Restricted Maximum Likelihood) techniques using a multi-trait, reduced animal model in a derivative-free way. Genetic and phenotypic correlations were estimated from four subsets of data consisting of 1) female September weight, litter size, and kit mortality; 2) body size traits; 3) September weight and fur traits graded on live mink; and 4) fur traits graded on live mink and skins. September weight was found to be negatively correlated with fertility and fitness traits as well as with fur traits. Selection for underfur density resulted in an improvement in guard hair quality and in general impression of the fur and almost eliminated the fur defect metallic sheen.  相似文献   

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Thirty cadaver dissections and injections of the pancreatic caudal arteries brought the authors to the conclusion that the ligature of a recurrent artery (going from the splenic hilum to the pancreatic cauda) is an exceptional cause of acute pancreatitis after splenectomy : this complication is more often due to direct trauma to the pancreas.  相似文献   

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BACKGROUND: The benefit of splenectomy, performed for complications of chronic lymphocytic leukemia (CLL) including autoimmune hemolytic anemia, thrombocytopenia, hypersplenism, and symptomatic splenomegaly, has not been clearly demonstrated. The objective of this study was to determine if splenectomy achieves a predictable hematologic and survival advantage over conventional chemotherapy in patients with CLL. STUDY DESIGN: A retrospective review was performed of 77 consecutive patients with CLL who underwent splenectomy between 1970 and 1994 at the University of Texas M. D. Anderson Cancer Center. Indications for splenectomy, pre- and postoperative hematologic profiles, response to splenectomy, and time to progression and death were recorded. Kaplan-Meier life tables were constructed, and a comparison to an age- and gender-matched cohort of CLL patients treated with fludarabine and no splenectomy was performed using log rank statistical analysis. RESULTS: Seventy-six percent of the patients studied were Rai stage III/IV. Twenty of 29 patients with hemoglobin counts (Hb) < or = 10 g/dL and 11 of 18 patients with platelet counts (plt) < 50 x 10(9)/L achieved an excellent hematologic response to splenectomy. Splenectomy significantly improved survival in patients with Hb < or = 10 g/dL or plt < or = 50 x 10(9)/L (p = 0.025). Thrombocytopenia did not significantly increase postoperative morbidity, and mortality rate was not significantly different between treatment groups. CONCLUSIONS: Splenectomy significantly improves survival in selected subgroups of patients with advanced-stage CLL over that achieved with conventional chemotherapy. Based on these results, splenectomy should be performed early in the course of the disease in CLL patients with either an Hb < or = 10 g/dL or plt < or = 50 x 10(9)/L.  相似文献   

12.
A homogeneous sample of 56 women who were between the ages of 20 and 59 years and worked in acute emergency care, child psychiatry, or a pediatric outpatient clinic comprised the subjects of this study to determine the relationship between job strain and blood pressure. Job strain was measured with a standardized questionnaire, and blood pressure during workhours with self-triggered equipment. Endocrine factors (morning concentration of plasma prolactin, cortisol, and dehydroepiandrosterone) and emotional states recorded in diaries were also studied. Significant interrelationships occurred among perceived job strain, plasma prolactin, and diastolic blood pressure during workhours even when body mass index, age, family history of hypertension, level of education, and mood state were adjusted for in a multiple regression analysis. Thus job strain of female care givers was associated with systolic and diastolic blood pressure during workhours and also with diastolic blood pressure at rest, but not with blood pressure during leisure time.  相似文献   

13.
Blood coagulation and fibrinolysis parameters were studied during 10 days of total fasting in healthy, normal weight males. A reduction of plasma levels of factor VIII activity with a concomitant decrease in factor VIII antigen was found, without other laboratory evidence for a disseminated intravascular coagulation. The effect of 10 days' starvation on blood coagulation appears to be small but the effect of more prolonged starvation might implicate impaired hemostasis.  相似文献   

14.
A cadaveric arterial injection study was performed to study the effects of percutaneous and conventional surgical plating techniques on femoral vascularity. Sixteen-hole dynamic condylar screw and condylar buttress plates were applied on the proximal and distal shafts, respectively, of intact femora in ten human cadavers. On one side, the plate was inserted using a lateral conventional plate osteosynthesis (CPO) technique with elevation of the vastus lateralis muscle to expose the shaft. On the contralateral side, the plate was inserted percutaneously beneath the muscle using a minimally invasive plate osteosynthesis (MIPPO) technique. After plating, blue silicone dye was injected through the common femoral artery. A dissection was then performed to identify the femoral perforating arteries (PAs). The pattern of periosteal filling of the injected dye was analyzed. The MIPPO technique maintained the integrity of the PAs and exhibited superior periosteal perfusion. The results of this study indicate that the MIPPO technique maintains femoral vascularity and perfusion better than the CPO technique.  相似文献   

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A study of energy transfer of Er3 /Nd3 codoped tellurite glasses was presented. By Nd3 co-doping, both the Er3 green emission corresponding to the Er3 : (4S3/2, 2H11/2)→4I15/2 transitions and the red emission corresponding to the Er3 : 4F9/2→4I15/2 transitions were quenched. The energy transfer mechanism between Er3 and Nd3 was discussed based on their energy level characteristics. The interaction parameters, CD-A , for the energy transfer processes from Er3 to Nd3 in tellurites glass were calculated. Finally, the resonant transfer Er3 : 4I9/2→Nd3 : (4F5/2, 2H9/2) was proposed to be the most probable microscopic process to occur in contrast with the other processes.  相似文献   

17.
During the breeding season under long-day conditions, male canaries sing sexually attractive songs and females respond behaviorally to such songs. This study assessed whether auditory response properties of neurons in nucleus HVc of female and male canaries are tuned to sexually salient song features: special song phrases and canary song segmentation. In sexually receptive female canaries, neurons responded to special song phrases with a decreased spike rate and were sensitive to canary song segmentation. The nonreceptive females showed no clear response to special song phrases. In females on short days, neurons responded to song phrases with an increase in activity. In males on long days, they exhibited phasic responses after the phrase onset, whatever the song phrase and song segmentation. This study demonstrates both a plasticity in relation to females' sexual responsiveness and a sexual dimorphism in the auditory processing performed in the HVc. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

18.
Corticotropin-releasing factor (CRF) has previously been shown to selectively dilate the mesenteric vascular bed, without affecting other vascular beds. Pancreatic blood flow and islet blood flow were therefore measured separately with a microsphere technique in the two regions of the rat pancreas perfused by the superior mesenteric artery (SMA) or celiac artery (CA) respectively. Intravenous infusion of CRF (0.25 microgram/kg b.w./min) caused an increase in both whole pancreatic blood flow and islet blood flow in the region of the pancreas perfused by the SMA. The fraction of whole pancreatic blood flow diverted through the islets in this part of the pancreas was, however, unaffected by CRF infusion (approximately 10%). CRF did not change either pancreatic or islet blood flow in the CA-perfused part of the pancreas, and did not affect the release of insulin.  相似文献   

19.
The development of an informative, noninvasive technique for evaluating the reserve of the cerebral circulatory system is a topical task of clinical angioneurology. The authors developed methods of Doppler evaluation of an autoregulatory response from hyperemic changes after short-term regional hypotension caused by digital compression of the cervical carotid. They calculated the indices acceptable in routine clinical practice, defined the range of their values in health and in typical variants of cerebral circulatory insufficiency in patients with disseminated neurosurgical pathology. The carotid compression test by recording linear blood flow velocity in the cerebral arteries is a safe, valid, and reproducible method of semiquantitative assessment of the autoregulation reserve which may be used to determine the tension of resistive vessels in the middle cerebral arterial bed as an important index of the functional status of the cerebral circulatory system.  相似文献   

20.
The vascular pedicles of the semitendinosus, gracilis and sartorius muscles were identified by the authors. Although devascularisation of the tendons is of no importance in plastic operations, any technic using the fleshy part of these muscles should take care to preserve the blood supply. It is therefore important to know their anatomy.  相似文献   

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