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1.
According to the current World Health Organization (WHO), renal cell carcinomas (RCCs) that primarily affect adults are classified into 8 major subtypes. Additional emerging entities in renal neoplasia have also been recently recognized and these are discussed in further detail by Mehra et al (Emerging Entities in Renal Neoplasia, Surgical Pathology Clinics, 2015, Volume 8, Issue 4). In most cases, the diagnosis of a RCC subtype can be based on morphologic criteria, but in some circumstances the use of ancillary studies can aid in the diagnosis. This review discusses the morphologic, genetic, and molecular findings in RCCs previously recognized by the WHO, and provides clues to distinction from each other and some of the newer subtypes of RCC. As prognosis and therapeutic options vary for the different subtypes of RCC, accurate pathologic distinction is critical for patient care.  相似文献   
2.
慢性病信息系统的指标及其收集方法的研究   总被引:2,自引:0,他引:2  
目的 探讨我国目前慢性病监测系统应监测的指标、指标的收集方法。方法 DELPHI专家咨询法。结果 目前社区慢性病综合防治信息系统包括的指标有六方面内容,按照平均重要程度等级和排位的结果是死亡监测、发病或患病监测、危险因素监测、社区环境监测、疾病管理与卫生经济监测;指标的收集渠道应统一协调卫生系统的各个部门,包括医院、社区和各级疾病预防控制机构(CDC)以及公安和民政等部门;指标的收集方式主要依靠常规报告,部分指标通过流行病学调查来获得;监测指标的用途主要用于探测慢性病流行趋势和引起的疾病负担、确定防治重点、评价慢性病干预效果,以便更有效的防治慢性病;如何确保监测资料的质量和政府提供必须的费用是监测中比较普遍存在的问题。结论 死亡监测、发病或患病监测、行为危险因素监测应是慢性病综合防治信息系统应首选的内容。  相似文献   
3.
以苏州七子山垃圾填埋场为背景,采用理论分析的方法,探讨山谷型垃圾填埋场合理的渗滤液收集系统的形式和定量计算方法。  相似文献   
4.
The effect of prostaglandin on diffusional water permeability has been studied in collecting ducts in an isolated rat papilla. PGE2 increased water permeability. The effect was significant at a concentration of 10–8 mol l–1 and was maximal with a concentration of 10–6 mol l–1. The maximal increment of 0.94±0.10 (SEM) m s–1 was approximately half that produced by maximal stimulation with antidiuretic hormone (2.18±0.12 m s–1).A concentration of 10–8 mol l–1 produced an increase in basal water permeability and 25 unit ml–1 ADH, which without PGE2 present gave a similar increase, had no incremental effect. ADH 100 unit ml–1 increased permeability to a value similar to that observed in the absence of PGE2. Thus PGE2 and ADH both increase water permeability but the increments are not additive.Indomethacin in a concentration that inhibited prostaglandin production altered the response of the collecting duct to ADH. The dose response curve was shifted to the left and the maximal increase in water permeability and the lowest dose at which a response occurred took place at concentrations less than 1/2 those required in its absence.Prostaglandins influence the action of ADH and it is likely that in life they regulate and modulate the change in water permeability induced by anti-diuretic hormone.  相似文献   
5.
The ionic conductive properties were studied of epithelia of collecting duct principal cells which had been grown in primary tissue culture from renal cortex/capsule explants. When pretreated with aldosterone (10–6 mol/l) and bathed on either surface with isotonic HCO 3 -free Ringer's solution, the transepithelial voltage,V te, varied between –21 and –72 mV (apical surface negative) while the transepithelial resistance,R te, ranged from 0.4 to 1.5 kcm2. By 10:1 step-changes in Na+ concentration the apical cell membrane was shown to have a high conductivity for sodium, inhibitable by amiloride, 10–6 mol/l. However, contrary to observations in natural collecting duct under control conditions, amiloride never reversed the polarity ofV te even at 10–4 mol/l. Both the apical and the basolateral cell membranes were conductive for potassium and both conductivities were inhibitable by Ba2+ (5 mmol/l). 10:1 reduction of apical Cl concentration strongly hyperpolarizedV te with a monophasic time course suggesting the presence of a paracellular shunt conductance for Cl. In addition there may be a small Cl conductance present in the apical cell membrane since apical application of the chloride channel blocker 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPAB) at 10–7 mol/l produced a minute but significant hyperpolarization. On the other hand, 10:1 reduction of basolateral Cl concentration caused a biphasic change inV te (initial depolarization, followed by repolarization) which indicates the presence of a large Cl conductance in the basolateral cell membrane. The latter was not inhibitable by 10–7 mol/l NPPAB. Higher concentrations of this and of an other Cl channel blocker produced non-specific effects. In conclusion, our studies of a pure principal cell epithelium confirm findings described for the intact cortical collecting duct and add new information concerning chloride conductivity and related blocking agents.Dedicated to Prof. Dr. H. Sitte, Homburg, FRG, upon his 60th birthday.  相似文献   
6.
Intracellular microelectrode techniques were used together with inhibitors of Na+ transport (amiloride) and H+ transport (acetazolamide and SITS1) to identify principal cells and intercalated cells in the outer stripe of the rabbit outer medullary collecting duct. The principal cell (n=9) had a basolateral membrane voltage (V bl) of –64.7±3.2 mV, a fractional resistance of the apical membrane (fR a=R a/R a+R bl) of 0.82±0.02, and a K+-selective basolateral membrane. Luminal amiloride hyperpolarizedV bl by 10.3±2.1 mV and increasedfR a to near unity (n=7). Bath acetazolamide and SITS were without effect on these parameters. The intercalated cell (n=5) had aV bl of –25.0±3.2 mV, afR a of 0.99±0.01, and a Cl-selective basolateral membrane. Bath acetazolamide or SITS hyperpolarizedV bl by 26.4±8.2 mV. Luminal amiloride did not alterV bl of this cell. The differential effects of the inhibitors also indicate that the principal and intercalated cells are probably not directly coupled electrically.  相似文献   
7.
To examine the effect of hydroxyapatite (HAP) seed crystals and urinary macromolecules on the crystallization under conditions similar to those in the collecting duct, we evaporated 100 ml samples of salt solutions with an ion composition assumed to correspond to that in the collecting duct without and with HAP seed crystals. The crystallization in seeded solutions was assessed both with and without dialysed urine (dU). After evaporation the number and volume of crystals were recorded in a Coulter Multisizer and the crystal morphology examined with scanning electron microscopy (SEM) and X-ray crystallography. Addition of HAP crystals was apparently followed by an approximately 15–20% increase in heterogeneous nucleation of calcium oxalate (CaOx). In these experiments SEM and X-ray crystallography showed a high percentage of CaOx in the precipitate. In samples reduced to 40–69 ml, addition of dU to the collecting duct solution containing HAP seed resulted in a greater mean (SD) number of crystals; 3895 (1841) in samples with dU and 1785 (583) in samples without. This was mainly explained by an increased mean (SD) number of small crystals. The mean crystal volume was 17.8 (1.1) and 34.3 (9.1) in samples reduced to 40–69 ml with and without dU, respectively. This might reflect the inhibitory effect of dU on the growth and/or aggregation of the CaOx-CaP precipitate or a promoted nucleation resulting in a large number of small crystals. It is concluded that calcium phosphate formed above the collecting duct might induce heterogeneous nucleation of CaOx at lower levels of the renal collecting system, and that urinary macromolecules are powerful modifiers of these processes. Received: 8 July 1998 / Accepted: 12 March 1999  相似文献   
8.
9.
陈曦 《北方药学》2014,(12):31-32
乐山产川泽泻的主要成分为23-乙酰泽泻醇B。按《中国药典》(2010版)泽泻含量测定方法比较,对乐山地区不同育苗期、移栽期、采收期的川泽泻进行质量研究。结果显示,在6月25日育苗、8月27日移栽和12月25日采收的乐山产川泽泻的总体质量最佳。  相似文献   
10.
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