Immune suppression is a very important mechanism in alleviating immunologic injury,and recent study has showed that CD4~(+)CD25~(+) regulatory T cell is an important component of the immune suppression system.This T cell subset has an obvious immune-suppressing effect and produces its effect not by secreting cytokine but contacting cell directly.In this review,we describe the biological characteristics of CD4~(+)CD25~(+) regulatory T cell and its functions in infection immunity.

Objective To evaluate the learning curve in percutaneous nephrolithotomy under the guidance of B ultrasonography.Methods From January 2006 to July 2007,totally 60 cases of percutaneous nephrolithotomy were performed under the guidance of B ultrasonography by a single urologist.The patients were divided into 6 groups according to the date of the operation(10 cases in each).The time for setting the renal access and the stone-free rate were compared among the groups.Results The time for setting the renal access was(15.0?2.7),(14.0?2.1),(10.2?1.2),(5.8?0.7),(7.5?1.2),and(6.6?0.9)minutes respectively in group 1 to 6.ANOVA analysis showed significant difference among the groups(F=5.734,P=0.000).Significant difference was detected between groups 1 and 4(q = 5.655,P

Objective To evaluate the clinical application of enhancement scan and angiography of dual-source computed tomography (CT) in purulent meningitis.Methods The clinical data,imaging data of enhancement scan and angiography of dual-source CT of 8 cases with purulent meningitis were analyzed retrospectively.Results There was linear or bead-like high intensity enhancement of different degree around the cistern,groove or the cerebral vessels in 6 cases,especially around the basal cistern and ambient cistern; a ring-like enhancement was shown in the temporal lobe in 1 case; fusiform change of the cerebral arteries was shown in angiography of dual-source CT in 2 cases.Conclusion Enhancement scan and angiography of dual-source CT is valuable for early diagnosis of purulent meningitis and improve the diagnosis rate.

Objective To evaluate the efficacy and safety of ultrasonography-guided percutaneous nephrolithotomy(PCNL).Methods Between May 2006 and June 2008,110 patients underwent PCNL by a single urological team at our hospital.The clinical data of the patients were retrospectively reviewed.Of the cases,supracostal access(the 11th intercostal space) was made in 62 patients(supracostal group),and subcostal access was obtained in 48 patients(subcostal group).Forty-five patients in the supracostal group(45/62) and 36 of the subcostal group(36/48) received CT three dimensional reconstruction.Results The stone free rate of the supracostal group was 72.6%(45/62),while that of the subcostal group was 60.4%(29/48;?2=1.818,P=0.178).The mean operation time of the supracostal group was(78.6?5.1) min,while that of the subcostal group was(102.4?7.1) min(t=-20.454,P=0.000).There was one patient in each group received blood transfusion.One patient in the supracostal group had pneumothorax and recovered uneventfully by conservative treatments.Conclusion Ultrasonography-guided PCNL via the supracostal approach is effective and safe with short operation time.

Objective To evaluate the efficacy of combination of traditional educational methodology with problem-based learning pedagogy in urology.Method The traditional educational pedagogy of urological tuberculosis was modified by combining with PBL methodology.Result More students were interested and active in this pedagogy.Conclusion The combination of traditional educational methodology with PBL is a helpful pedagogy.

Objective To investigate the species and distribution of Mussaenda L. in Guangxi, and provide basis for protecting, developing and utilizing the local plant resources. Methods By field survey, specimens collection and identification and literatures consultion, Mussaenda L. in Guangxi was investigated. Results Mussaenda L. in Guangxi contains 8 species, and the majority of them are Mussaenda pubescens Ait.f and Mussaenda eros Champ. Conclusion The investigation results provide some basis for protection, development and utilization of the resources of Mussaenda L. in Guangxi.

OBJECTIVE:To establish a method for the determination of 100 pesticide residues in Morus alba. METHODS:LC-MS/MS was conducted on the column of ZORBAX Eclipse plus C18 with mobile phase of acetonitrile (containing 5% water, 0.1% formic acid,5 mmol/L ammonium formate)- water(containing 0.1% formic acid,5 mmol/L ammonium formate)(gradient elution)at a flow rate of 0.4 ml/min,column temperature was 40 ℃,injection volume was 5 μl;MS conditions:ionization source was electrospray ionization with positive ion mode,scanning mode was dynamic MRM,scanning time window was 2 min;atomiz-ing gas was nitrogen,atomizing gas pressure was 40 psi,drying gas flow rate was 5 L/min,capillary voltage was 4 000 V,and ion spray voltage was 500 V. RESULTS:The linear range of 100 pesticide residues was 2.4-150 ng/ml(r>0.990 0),recovery was 69.3%-128.2%,and the determination limit was 0.003-16 μg/kg. CONCLUSIONS:The method is simple,stable and reproduc-ible,and can be used for the determination of pesticide residues in M. alba.

Objective To analyze the features of dynamic contrast-enhanced CT of blunt hepatic injury in rabbits. Methods The model of blunt hepatic injury was established in 40 New Zealand white rabbits with a steel ball falling down to the xiphoid process of the animals. Plain CT scan and dynamic contrast-enhanced CT scan (Hispeed spiral CT/2i, GE, America) of the liver were performed. Arterial,portal and balanced phases were respectively at 8-10 s, 35-40 s and 120-150 s after initiation of the contrast medium injection. The non-enhanced and enhanced images were compared in aspects of location and range of injury, tear of the liver capsule, active bleeding, involvement of the main hepatic veins and CT features of abdominal hemorrhage, which was further compared with the results of gross anatomy. Results The rate of plain CT scan was obviously lower than that of dynamic contrast-enhanced CT scan,which defined single tear in 13 patients, multiple lacerations in 18, liver subcapsular hematoma in seven,liver hematoma in nine, liver coated gap in 17, active bleeding in nine and main hepatic vein injury in five, with coincidence rates with the results of gross observation for 13/13,18/18,7/9,9/9,25/30,9/5and 5/4 respectively. According to Moore' s classification, CT/Laparotomy performed from grade Ⅰ to grade Ⅵ were 5/4 patients at grade Ⅰ , 15/13 at grade Ⅱ, 9/11 at grade, 5/6 at grade Ⅳ, 1/2 at grade Ⅴ, O at grade respectively. Conclusion Dynamic contrast-enhanced CT scan, especially at portal and balanced phases, is of great value for diagnoses of liver injuries and determination of injury severity.

Objective:To perfect and improve the quality standard of Malloti Apeltae Radix. Methods:Microscopic identification was used to identify the transverse section and the powder. The water-soluble and the fat-soluble components were identified by TLC. Rutin was used as the reference in the characteristic chromatogram established by HPLC to determine the relative retention time and rel-ative peak area of each characteristic absorption band. A SPOLAR C18 chromatographic column ( 250 mm × 4. 6 mm,5μm) was used with acetonitrile-0. 4% phosphate solution as the mobile phase with gradient elution, the detection wavelength was set at 328 nm, the flow rate was 1. 0 ml·min-1, and the temperature was 35℃. Results: The microscopic characteristics were obvious. The spots of TLC were round and clear with good repeatability. Five characteristic absorption bands were shown in the fingerprints with the relative retention time within ± 5% of reference value of rutin, and the relative area of peak 3 and peak 4 was not lower than 0. 23 and 0. 66, respectively. Conclusion:The method is convenient, fast and repeatable, and the result is accurate and reliable, which can be used to control the quality of Malloti Apeltae Radix effectively, and as the main index of the quality standard.

Objective: To investigate the position and the size of ureteral stone in patients before treated with ureteroscopic lithotripsy or percutaneous nephrolithotomy (PCNL), as well as the dilatation of ureter caused by stone, which may be helpful for better understanding of pathogenesis of ureteral stone and improvement of the diagnosis and treatment in clinic.Methods: A total of 129 cases with ureteral stone for endourologic lithotripsy in Peking University People''s Hospital from Aug.2016 to Mar.2017 were included for the retrospective review.The CT data of the ureteral stones and the ureteral dilatation were collected, including the position of stone, the transverse and longitudinal diameter of stone, and the transverse diameter of dilated upper ureter and ureteropelvic junction (UPJ).The distribution of ureteral stones and dilatation in different parts of ureter were compared and analyzed.Results: All of the 129 cases of ureteral stone, stones were located at UPJ in 9 cases (7.0%), proximal ureter in 75 (58.0%), ureter crossing external iliac vessel (UEIV) in 6 (4.7%), distal ureter in 26 (20.2%), and ure-terovesical junction (UVJ) in 13 (10.1%).The mean transverse diameter of proximal ureteral stones was greater than that of distal ureteral stones [(8.47±2.36) mm vs.(6.74±1.99) mm, P<0.001], as the same as the mean longitudinal diameter [(11.00±4.41) mm vs.(7.50±4.28) mm, P<0.001].In 114 cases of dilated ureter for stone, the UPJ had a greater transverse diameter compared with the upper ureter [(14.39±6.09) mm vs.(11.45±3.85) mm, P<0.001].Conclusion: The most common location of stone is the proximal ureter in patients for endourologic lithotripsy, as the location in UEIV is rare.Both transverse and longitudinal diameters of stone in proximal ureter are greater than those in distal ureter.For dilated ureter, it is more severe in UPJ than in upper ureter.Traditionally, it is accepted that the stones lodge at 3 sites of natural narrowing in ureter, which may be questioned.