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151.
In the human embryo, the first anlage of the bile ducts and the liver is the hepatic diverticulum or liver bud. For up to 8 weeks of gestation, the extrahepatic biliary tree develops through lengthening of the caudal part of the hepatic diverticulum. This structure is patent from the beginning and remains patent and in continuity with the developing liver at all stages. The hepatic duct (ductus hepaticus) develops from the cranial part (pars hepatica) of the hepatic diverticulum. The distal portions of the right and left hepatic ducts develop from the extrahepatic ducts and are clearly defined tubular structures by 12 weeks of gestation. The proximal portions of the main hilar ducts derive from the first intrahepatic ductal plates. The extrahepatic bile ducts and the developing intrahepatic biliary tree maintain luminal continuity from the very start of organogenesis throughout further development, contradicting a previous study in the mouse suggesting that the extrahepatic bile duct system develops independently from the intrahepatic biliary tree and that the systems are initially discontinuous but join up later. The normal development of intrahepatic bile ducts requires finely timed and precisely tuned epithelial–mesenchymal interactions, which proceed from the hilum of the liver toward its periphery along the branches of the developing portal vein. Lack of remodeling of the ductal plate results in the persistence of an excess of embryonic bile duct structures remaining in their primitive ductal plate configuration. This abnormality has been termed the ductal plate malformation. Anat Rec, 291:628–635, 2008. © 2008 Wiley‐Liss, Inc. 相似文献
152.
G. Kahraman T. Marur E. Tanyeli M. Yildirim 《Surgical and radiologic anatomy : SRA》2002,23(6):433-435
Abstract An hepatomesenteric trunk, formed by the common hepatic and superior mesenteric arteries, was found in a 50-year-old male cadaver. The left gastric and splenic arteries arose as a common trunk, the gastrosplenic trunk, from the abdominal aorta; no typical celiac trunk was present. In addition, the hepatomesenteric trunk passed posterior to the portal vein. A knowledge of variations of the common hepatic artery may be important in pancreaticoduodenectomy, as well as during hepatic artery infusion chemotherapy. 相似文献
153.
Summary Porphyria cutanea tarda (PCT) was diagnosed in 27 women aged 23–48 years (mean, 35 years) who had been under oral-hormonal-contraceptive medication for 1–18 years, in 3 women under substitutional estrogen treatment in the menopause, and in 2 men aged 65 and 76 years after estrogen treatment of prostatic carcinoma. In all patients, total urinary porphyrin excretion was elevated, with an average uro-and heptacarboxyporphyrin predominance of 88%, thus proving PCT. On the patients, 84% showed a significant decrease of erythrocyte uroporphyrinogen-decarboxylase (UD; EC 4.1.1.37) activity to 50% of control levels suggesting a hereditary predisposition for the development of a chronic hepatic porphyria. Estrogens and alcohol are capable of reducing hepatic UD activity. Women with hereditary red cell UD deficiency may be regarded as predisposed to PCT when under estrogen intake, especially in combination with the potentiating influence of alcohol and chronic liver disease. Normal erythrocyte UD values in patients with additive alcohol consumption may implicate a stronger inhibitory effect for alcohol on UD, suggesting a merely toxic form of chronic hepatic porphyria. 相似文献
154.
Summary Two hundred twenty five patients with intracranial lesions underwent diagnostic and therapeutic stereotactic surgery during the period 1978–1985. In the first 98 cases target coordinates were determined by transferring the information from the CT images to the standard stereotactic films. In the remainder, a simple, CT adapted stereotactic system has been used. Operations were as a rule performed under local anaesthesia. Positive histological diagnosis using paraffin embedding was achieved in 96% of the patients (biopsy success rate). Therapeutic procedures included abscess and cyst aspiration, cyst shunting, interstitial (Ir 192) or intracavitary (Y 90) irradiation and ventriculocisternostomy. Stereotactic surgery implied a refinement of the eventual therapeutic management in 90% of the cases. Transient neurological deficit occurred in 5.7% of the patients and there were three deaths (mortality rate 1.3%). Infection or other complications were not seen. The rationale and indications for non-functional stereotaxis are discussed. 相似文献
155.
The liver is a major site for synthesis and catabolism of plasma proteins. Albumin has various binding sites for anionic drugs,
1acid glycoprotein possesses a single binding site for cationic drugs. In spite of extensive protein binding, the liver can efficiently remove drags from the circulation. Intrahepatic dissociation of the drag-protein complex may involve dissociation-limited debinding under non-equilibrium conditions or surface interaction-facilitated dissociation phenomena. During liver or renal disease and acute-phase conditions plasma protein binding of drugs may be affected. Changes in the unbound drag fraction do not always result in proportional changes in clearance or distribution volume. Potential changes in the unbound concentration in steady-state as well as the fluctuations in total plasma levels depend on the extent of protein binding of a drug, the relative change in the unbound drug fraction, type of clearance, the size of the distribution volume, route of administration as well as concomitant changes in intrinsic (cellular) clearance function. Optimization of dosage regimens for certain drags and interpretation of liver function tests with diagnostic dyes may largely benefit from determination of the unbound rather than the total concentration of the drags involved.Part of this work was supported by Grant 900-521-078 from MEDICON, which is subsidized by The Netherlands' Organization of Pure Research. 相似文献
156.
Juan F. Martinez-Lage Miguel A. Perez-Espejo José Masegosa Máximo Poza 《Child's nervous system》1986,2(4):208-210
The case of a 4-year-old girl who developed bilateral brain abscesses complicating skull traction is reported. Crutchfield tongs were used to reduce a fracture dislocation at C2–3. Presenting symptoms consisted of headaches and focal seizures. Surgical treatment and antibiotics using serial CT led to a satisfactory outcome. This is the first reported case of this complication in a child. The current literature is reviewed.To whom offprint requests should be addressed at Avda. Pio Baroja 4, 30011 Murcia, Spain 相似文献
157.
E. Piazza A. Condorelli R. Arcidiacono R. Tropea I. Chiaramonte Dr. P. Mancuso 《Acta neurochirurgica》1986,83(3-4):116-120
Summary Toxoplasma gondii cerebral abscess is a common opportunistic infection in patients affected by AIDS. Making a reliable diagnosis of acute cerebral toxoplasmosis is difficult in AIDS patients because of the lack of specificity of serological data and neuroradiological findings. Brain biopsy is the only procedure which enables a reliable diagnosis to be made a trial of specific medical therapy for toxoplasmosis in patients affected by AIDS and intracranial mass lesion can be advisable before performing brain biopsy. The authors report the cases of three patients affected by AIDS and cerebral toxoplasmosis.Tissue diagnosis was made in the first patient from autopsy material while a presumptive diagnosis was made in the other two cases since specific medical therapy resulted in a dramatic improvement of the neurological status.Despite the good possibilities in the treatment of this complication AIDS, however, carries a poor prognosis. 相似文献
158.
For a drug with concentration-dependent serum protein binding, the unbound fraction of drug decreases during the drug elimination process. The clearance of the drug at a given blood flow rate is lower than would be expected from the observed unbound fraction in venous blood from a noneliminating organ. Based on both the well-stirred and parallel tube models, simulations demonstrated that consideration of concentration-dependent binding during drug elimination is important when the intrinsic clearance is higher than the blood flow and when the unbound drug concentration is much greater than the dissociation equilibrium constant of the binding complex.Supported in part by Grant GM 28423 from the National Institutes of General Medical Sciences, NIH. 相似文献
159.
目的探讨超声清创联合重组人表皮生长因子对肛周脓肿合并感染患者表皮细胞生长因子(Epidermal growth factor,EGF)、激活素A(Activin A,ACTA)水平及创面血流量的影响。方法选取2018年2月-2020年1月承德医学院附属医院肛周脓肿合并感染患者117例,依据随机数字表法分为对照A组(n=39)、对照B组(n=39)、联合组(n=39)。常规干预基础上对照A组采取超声清创,对照B组采取重组人表皮生长因子,联合组采取超声清创及重组人表皮生长因子。统计三组治疗情况、治疗前后疼痛程度评分、创面血流量及经皮氧分压、EGF、转化生长因子-β(Transforming growth factor-β,TGF-β)、ACTA、C-反应蛋白(C-reactive protein,CRP)水平及临床疗效。结果联合组创面愈合时间、感染控制时间、住院时间分别为(12.39±2.01)d、(5.22±1.56)d、(13.91±2.51)d短于对照A组、对照B组,创面细菌清除率为(89.13±4.64)%高于对照A组、对照B组(P<0.001);治疗后1 d、3 d、7 d、14 d三组VAS评分较治疗前降低,且联合组低于对照A组、对照B组(P<0.05);治疗后1 d联合组创面血流量及经皮氧分压分别为(0.92±0.25)PU、(35.69±3.20)mmHg大于对照A组、对照B组(P<0.05);治疗后1 d联合组血清EGF、TGF-β分别为(0.70±0.11)μg/L、(0.68±0.12)μg/L高于对照A组、对照B组(P<0.05);治疗后1 d联合组血清ACTA、CRP分别为(9.45±3.58)μg/L、(5.71±2.68)mg/L低于对照A组、对照B组(P<0.05);联合组疗效优于A组和B组(P<0.05)。结论联合采取超声清创及重组人表皮生长因子治疗肛周脓肿合并感染,可改善创面愈合及感染控制情况,缓解疼痛程度,增加创面血流量及经皮氧分压,调节EGF、ACTA等水平,提高整体治疗效果。 相似文献
160.
肝脏局灶性小占位的磁共振信号强度比与病灶性质的相关性 总被引:1,自引:0,他引:1
目的 计算肝细胞癌、肝转移瘤、肝脏海绵状血管瘤和肝囊肿的病灶/肝脏磁共振信号强度比(SIR),并评价其与病灶性质的关系。方法 随机选择经确诊的肝细胞癌、肝转移瘤、肝海绵状血管瘤和肝囊肿病例共92例(148个病灶)行前瞻性磁共振成像(0.5T)研究。计算4种病灶的SIR,并进行统计学分析。结果 在T1W图像上,肝海绵状血管瘤与恶性肿瘤的SIR值间差异无显著性(t=1.799,P=0.075);质子加权像上,良恶性肿瘤的SIR之间无统计学意义(t=0.691,P=0.491);T2WI上,良性病变的SIR显著高于恶性肿瘤(P<0.01),且4种病变的SIR值与回波时间(TE)之间均存在线性正向相关关系。结论 在T2WI个测得的SIR可用于区分肝脏占位性病灶的性质。 相似文献