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1.
Blood from the adrenal gland can flow in two directions--into the caudal vena cava and by anastomoses into the portal vein. A method of multiple blood procuring from these vessels in dogs for the purpose of studying the adrenal gland function is suggested. Polyethylene catheters, 0.9 mm in diameter and 35--40 mm in length glued to capron plates, mandrins, Gordeev's needles and blood-drawing needles are necessary. Transperitoneal surgical approach to the caudal and mesenteric veins is to be provided. Purse-string suture is applied on the wall of the mesenteric vein. The catheter is washed with heparin, the mandrin is introduced into it and it is inserted into the Gordeev's needle. A puncture is made in the centre of the purse-string suture with this needle, which is introduced into the vein together with the catheter. Gordeev's needle is withdrawn and the catheter is pushed through to the portal vein. The purse-string suture is tightened, and the capron plate is fixed in the wall of the vein. The mandrin is recovered from the catheter, heparin is administered into its canal, polyethylene plug is inserted and withdrawn through the abdominal wall outside with the aid of the blood-drawing needle. The catheter is introduced into the caudal vena cava in the same way. Blood samples can be obtained on the 14th postoperative day. 相似文献
2.
Molsidomine is well absorbed by the gastro-intestinal tract and is taken up by the liver during the first passage. Its bioavailability is 60 per cent. Digestive or sublingual absorption is rapid: maximal plasma concentrations are obtained 0.5 to 1.0 hours after administration. Molsidomine is minimally bound by plasma proteins and is distributed in a volume of 1 litre/kg. The excretion is essentially extrarenal: less than 2 per cent of the administered dose is excreted in the form of unchanged molsidomine. Molsidomine is metabolized in the liver to two pharmacologically active metabolites which spontaneously and rapidly breakdown into inactive metabolites which are excreted by the kidneys. The plasma half-life of molsidomine is 1 to 2 hours: it is not modified in patients with renal failure, but it is prolonged in patients with hepatic failure. The kinetics are linear and independent of the route of administration and the dose. There is a correlation between the plasma concentration and the pharmacological effect: the minimal effective concentration is about 5 ng/ml. At the usual dose of 2 mg three times a day, there is no accumulation of the drug. 相似文献
3.
Nobis N 《The American journal of the medical sciences》2011,342(4):297-304
It is argued that using animals in research is morally wrong when the research is nontherapeutic and harmful to the animals. This article discusses methods of moral reasoning and discusses how arguments on this and other bioethical issues might be defended and critiqued. A basic method of moral argument analysis is presented and used to show that common objections to the view that "animal research is morally wrong" fail: ie, common arguments for the view that "animal research is morally permissible" are demonstrably unsound or in need of defense. It is argued that the best explanations why harmful, nontherapeutic research on human beings is wrong, ie, what it is about humans that makes such experimentation wrong, apply to many animals as well. Thus, harmful and nontherapeutic animal experimentation is wrong for reasons similar to the reasons that harmful and nontherapeutic human experimentation is wrong. 相似文献
4.
Diabetic foot is one of challenging diseases in vascular surgery. This is based on uncontrolled diabetes mellitus and its true character is the neuropathic gangrene due to microangiopathy. Diabetic foot, however, is sometimes accompanied by peripheral arterial occlusive disease, which true status is macroangiopathy. Therefore, the strategy for diabetic foot is as follows;the first step is the infection control by minor amputation and/or drainage, the second step is the assessment of the limb ischemia, and the final is the complete vascular reconstruction. To salvage these diabetic feet, it is important that doctors, who concern to diabetics, understand these strategies and also that they have a settled opinion for the diabetic foot. 相似文献
5.
肝纤维化是多种慢性肝病的共同病理过程,可导致肝硬化及相关并发症的发生,而肝纤维化具有可逆性。因此,肝纤维化诊断对慢性肝病的防治及预后评估具有重要意义。肝活检一直是诊断肝纤维化的金标准,但有其局限性,近来研究发现血清学指标与肝纤维化之间有良好的相关性,且简便易行,有望替代肝活检,本文就血清学检查在肝纤维化诊断中的研究作一概述。 相似文献
6.
Poly aluminum-ferric Chloride (PAFC) is a new type of high efficiency coagulant. In this study, high iron type gangue is used as a main raw material. It is calcined at 675 °C for 1 h and 3% CaF2 is added to the calcined powder and reacted with 20% hydrochloric acid at 93 °C for 4 h. The leaching ratio of aluminum ions is 90% and that of iron ions is 91%. After Fe2+ ions are oxidized in the filtrate, CaCO3 is used to adjust the pH of the filtrate to 0.7. The microwave power is adjusted to 80 W and the filtrate is radiated for 5 min. After being aged for 24 h, PAFC product is obtained. The prepared PAFC is used to treat mine water and compared with the results of PAC and PAF, the turbidity removal ratio of PAFC is 99.6%, which is greater than 96.4% of PAC and 93.7% of PAF. PAFC is a mixture with different degrees of polymerization. It demonstrates that extracting aluminum and iron ions from high iron content gangue to prepare PAFC by microwave is efficient and feasible. 相似文献
7.
M Kimura J F Crow 《Proceedings of the National Academy of Sciences of the United States of America》1978,75(12):6168-6171
The selective advantage of an allele Gi (relative to the mean of alleles at this locus) is given by (formula: see text) in which Ai is the average excess of the allele on the character, X; W(X) is the fitness function; F(X) is the frequency function; W is the mean fitness; and the prime denotes differentiation. With truncation selection si = AaF(C)/w in which F(C) is the ordinate at the culling level and w is the proportion saved; this does not depend on any assumption about the distribution of F(X). If the character is normally distributed, si = AiI/sigma2, in which I is the selection differential and sigma2 is the variance of the character distribution. Finally, if the logarithm of the fitness is proportional to the squared deviation from the optimum and the character is distributed normally, si = AiK(Xop--m), in which Xop is the optimum value of the character, m is the mean value, and K is a constant determined by the variances of the fitness function and the frequency function. Truncation is the most efficient form of directional selection in the sense of producing the maximum gene frequency change for a given effect of the gene on the character, but fitness functions can depart considerably from sharp truncation without greatly reducing the efficiency. 相似文献
8.
Ischemic cardiac injury is the leading cause of heart failure and mortality in the USA and is a major expense to health-care systems. Once the heart is injured, a highly dynamic and coordinated immune response is initiated, which is dependent on both resident and recruited leukocytes. The goal of the inflammatory response is to remove ischemic and necrotic material and to promote infarct healing. If this system is perturbed, the myocardium heals poorly, leading to significant left ventricular dysfunction. Understanding how inflammatory cells coordinate and interact with each other is required prior to designing therapeutic interventions that target pathological processes at play and leave untouched those processes that are protective. This review will discuss the intercellular cross talk between cells of the innate immune system following myocardial ischemic injury and how that response is coordinated over time. 相似文献
9.
The aim of the present paper is to investigate the influence of factors in photopolymerization process that govern microhardness of three types of dental composites—universal (UC), bulk-fill (BC), and flowable (FC). Cylindrical specimens with different thicknesses are made and light cured. The significance of light intensity, irradiation time, and layer thickness on Vickers microhardness is evaluated by experimental design, analysis of variance, and regression analysis. It is found that the main factor influencing the microhardness on the top surface of the three composites is light intensity. The second factor is layer thickness for the UC and FC, while for BC, it is curing time. The third factor is curing time for the first two composites and layer thickness for bulk-fill. The significance of factors’ influence on the microhardness of the bottom surface is the same for the UC and FC, but different for BC. The main factor for the first two composites is layer thickness, followed by curing time and light intensity. For bulk-fill, curing time is main factor, light intensity is second, and layer thickness is last. Different significance of factors influencing the microhardness on top and bottom surfaces of investigated composites is revealed for the first time in the present study. 相似文献
10.
Local care and medical treatment for ischemic diabetic ulcers 总被引:3,自引:0,他引:3
Lazareth I 《Journal des maladies vasculaires》2002,27(3):157-163
Optimal medical treatment of ischemic diabetic ulcers is multifactorial. Infection is very common and it is necessary to distinguish between limb or life threatening infections and non-limb-threatening infections. The major pathogen associated with non-limb-threatening infection is staphylococcus aureus; oral antibiotics such as amoxicillin/clavulanate or clindamycin can be used. For severe infection, empiric antibiotic therapy is broader-spectrum covering staphylococci, streptococci, gram-negative bacilli and enterococci; intravenous administration is the rule. Duration of antibiotic therapy depends on severity and depth of infection, and on requirement of surgical debridment. Granulocyte colony-stimulating factor is a growth factor stimulating proliferation and function of neutrophils. As an adjunctive therapy for limb-threatening infections, it is associated with a lower rate of amputation. Increasing arterial perfusion if the patient is unsuitable for reconstructive surgery or angioplasty is desirable. Iloprost is an analogue of epoprostenol with effects on platelet aggregability and vasodilatation. It improves ulcer healing, decreases pain, slightly diminishes the rate of amputation. Systemic hyperbaric oxygen therapy can perhaps improve clinical outcome but additional research is needed to define the specific indications and benefits of this treatment modality. Local care is not rationalized and depends on local habits. Debridment is required. Non necrotic wounds can be covered by modern dressing (hydrophilic dressing, alginates, hydrocolloid). Necrotic wounds are dryed until surgical revascularization, or excised if they are limited and superficial. Pinch grafts are very useful for arterial ulcers. The place of topical growth factor like PDGF (platelet derived growth factor) and of living skin equivalents (dermagraft, apligraf) is not defined in ischaemic diabetic ulcers. Treatment of edema is necessary, because it retards or complicates healing. Inelastic bandages can be useful with good tolerance if ischemia is not critical. Pneumatic foot compression is under evaluation. Electric stimulation could be an adjuncting treatment, but with a problem of compliance. Reducing plantar pressure is always necessary. 相似文献
11.
Feldkamp G 《Zeitschrift für Rheumatologie》2008,67(6):478-484
The wrist is the most commonly involved joint in rheumatoid arthritis (RA). Because it becomes involved early in the disease course and because this involvement rapidly progresses, early and adequate treatment is necessary to prevent disease progression. Arthroscopic synovectomy is recommended for pain relief and functional recovery in early-stage RA and is also helpful in advanced RA. The technique is complicated, and the learning curve is steep, but its efficiency is high. Arthroscopic synovectomy of the wrist reduces pain and improves function in most cases. It also improves motion, which is an advantage to the open procedure, and patient acceptance of this procedure is high. Nevertheless, arthroscopic synovectomy may delay the need for complex surgery, such as wrist arthrodesis or total wrist arthroplasty in selected cases. 相似文献
12.
Asthma in the elderly 总被引:1,自引:0,他引:1
Braman SS 《Clinics in Geriatric Medicine》2003,19(1):57-75
Asthma is common in the elderly population and the differences between younger and older asthmatics should be appreciated (Table 2). Asthma is frequently overlooked in the geriatric population. Objective measures of pulmonary function can aid in a prompt diagnosis and lead to effective treatment and improved quality of life. Because smoking is an important risk factor for asthma-like symptoms of wheezing, cough, and sputum production, asthma is frequently confused with COPD. When airflow obstruction is found, attempts to demonstrate reversibility can uncover an asthmatic component to the disease. In patients who have asthma symptoms and no airflow obstruction, methacholine testing is helpful. When a normal methacholine challenge is present, a diagnosis of asthma can be excluded and the physician can pursue other diagnostic considerations such as heart failure, chronic aspiration syndrome, pulmonary embolic disease, and carcinoma of the lung. The onset of wheezing, shortness of breath, and cough in an elderly patient is likely to cause concern. Although the adage "all that wheezes is not asthma" is true at any age, it is especially true in the elderly. Diagnosis based on objective measures is essential. 相似文献
13.
M C Dauge C Bersay M Sarfati L Bocquet P Marland 《Archives des maladies du coeur et des vaisseaux》1985,78(2):279-281
A case of leiomyosarcoma of the inferior vena cava in a 74 year old woman is reported. The clinical and pathological features are described and the outcome and response to treatment analysed. This is a very rare form of malignant disease (less than 100 published cases) which mainly affects elderly women. The diagnosis is often made at a late stage because the symptomatology is not specific and because the tumour is so rare. Treatment is mainly surgical and is only possible in the infrarenal part of the inferior vena cava. It is very difficult or impossible to operate on the upper part of the vessel. The prognostic is poor. There are no reports of survival after 5 years. 相似文献
14.
Bronchiolitis obliterans and airways obstruction associated with graft-versus-host disease 总被引:1,自引:0,他引:1
G R Epler 《Clinics in Chest Medicine》1988,9(4):551-556
Bronchiolitis obliterans is a nonspecific pathologic lesion seen after fume inhalation and infections, which is associated with connective tissue disorders and is a complication of organ transplantation. Bronchiolitis obliterans with organizing pneumonia is also associated with the connective tissue disorders but is usually idiopathic and has better prognosis with corticosteroid therapy. Bone marrow-related obliterative bronchiolitis is limited to patients who develop chronic graft-versus-host disease. Symptoms begin with cough in 3 to 6 months and progress to dyspnea and severe airflow obstruction. The roentgenogram is normal or shows hyperinflation. Prognosis is poor and most patients develop disabling irreversible airflow obstruction. Bronchiolitis obliterans is the most important clinical complication in heart-lung transplant recipients. It is not preceded by typical features of chronic graft-versus-host disease, but has the same clinical course of dyspnea, airflow obstruction, and poor response to therapy. Bronchiolitis obliterans in transplant recipients may represent a form of allograft rejection. 相似文献
15.
Post-myocardial infarction cardiac rupture is an important complication and cause of death in the period following myocardial infarction. It is rarely diagnosed before death. However, early diagnosis is crucial as successful treatment is possible with surgery. A successful outcome is sometimes compromised by difficult anatomy or an extensive infarct. Presentation, diagnosis and treatment of cardiac rupture is reviewed in this article, and is illustrated by five cases of cardiac rupture. 相似文献
16.
Balloon angioplasty is being used with increasing frequency in the management of patients with peripheral vascular disease. Balloon angioplasty is useful alone and as an adjunct to conventional surgery. Angioplasty is relatively inexpensive, is performed under local anesthesia, and is associated with few complications. Technical success depends on the morphologic characteristics of a lesion and on the skill and experience of the operator. Long-term patency is more likely with larger vessels and short-segment stenosis. Careful selection of patients is vital and depends on cooperation between the vascular consultant and radiologist. PCTA is most often used at the extremes of clinical severity. Most complications are minor and do not require surgical treatment. The main disadvantage is the high incidence of restenosis. Angioplasty can be repeated easily, however, and its use does not preclude later surgery. 相似文献
17.
How we diagnose and treat deep vein thrombosis 总被引:31,自引:0,他引:31
Making a diagnosis of deep vein thrombosis (DVT) requires both clinical assessment and objective testing because the clinical features are nonspecific and investigations can be either falsely positive or negative. The initial step in the diagnostic process is to stratify patients into high-, intermediate-, or low-risk categories using a validated clinical model. When the clinical probability is intermediate or high and the venous ultrasound result is positive, acute symptomatic DVT is confirmed. Similarly, when the probability is low and the ultrasound result is normal, DVT is ruled out. A low clinical probability combined with a negative D-dimer result can also be used to rule out DVT, thereby obviating the need for ultrasonography. In contrast, when the clinical assessment is discordant with the results of objective testing, serial venous ultrasonography or venography is required to confirm or refute a diagnosis of DVT. Once a patient is diagnosed with an acute DVT, low-molecular-weight heparin (LMWH) is the agent of choice for initial therapy and oral anticoagulant therapy is the standard for long-term secondary prophylaxis. Therapy should continue for at least 3 months; the decision to continue treatment beyond 3 months is made by weighing the risks of recurrent thrombosis and anticoagulant-related bleeding, and is influenced by patient preference. Screening for associated thrombophilia is not indicated routinely, but should be performed in selected patients whose clinical features suggest an underlying hypercoagulable state. Several new anticoagulants with theoretical advantages over existing agents are undergoing evaluation in phase 3 studies in patients with venous thromboembolism. 相似文献
18.
Hyaluronic acid (HA) is implicated in functions such as vascularity, morphogenesis, repair, and the general integrity of the extracellular matrix. Hence, it is considered possible that HA is involved in the most conspicuous features of the progeroid phenotype. However, it is not known whether the increase in HA excretion seen in progeria patients is due to a primary genetic defect or is a secondary effect due to some deeper problem. The phenomenon of 'normal' aging is suggested to have a more complex etiology and phenotype than progeria and the role of HA levels is less well-defined. 相似文献
19.
The population of haemodialysis patients is increasing as is their age. There is a higher risk of cardiac comorbidities in these patients. Pacing is increasingly common in this group. We present a case highlighting the difficult issues and exemplifies the need for careful planning preprocedure. Haemodialysis patients often have difficult and limited vascular access. Insertion of pacing leads is associated with subclavian vein stenosis. If this is on the side of an AV fistula there is significant risk of losing the fistula with obvious consequences to the patient. Careful consideration of site and route of access needs to be made prior to pacing. The need for involvement of renal and vascular teams before starting the procedure is essential as it is paramount that the best route of access for pacing wires is selected. 相似文献
20.
《Baillière's clinical gastroenterology》1997,11(4):781-800
Primary sclerosing cholangitis (PSC) is a chronic, progressive cholestatic liver disease whose aetiopathogenesis is unknown. PSC is frequently associated with inflammatory bowel disease, in particular chronic ulcerative colitis, is most commonly observed in young males and is clinically characterized by fatigue, pruritus and jaundice. The diagnosis is supported by a cholestatic biochemical profile and histological abnormalities, and confirmed by visualization of an abnormal biliary tree. The natural history of the disease is currently being evaluated but is generally recognized to be slowly progressive, leading to complications of chronic cholestasis, portal hypertension and biliary cirrhosis. There is no specific medical treatment, and orthotopic liver transplantation remains the only definitive treatment for patients with end-stage PSC. A more rational approach to medical therapy will ensue upon a better understanding of the aetiopathogenesis of this disease. 相似文献