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1.
The degradation and tissue compatibility characteristics of a novel class of biodegradable poly(anhydride-co-imide) polymers: poly[trimellitylimidoglycine-co-1,6-bis(carboxyphenoxy)hexan e] (TMA-gly: CPH) (in 10:90; 30:70 and 50: 50 molar ratios) and poly[pyromellitylimidoalanine-co-1,6-bis(carboxyphenoxy)hexa ne] (PMA-ala:CPH) (in 10:90 and 30:70 molar ratios) were investigated and compared with control poly(lactic acid/glycolic acid) (PLAGA in 50:50 molar ratio) matrices, a well-characterized biocompatible polymer, in rat subcutaneous tissues for 60 days. Polymers were compression-molded into circular discs of 14 mm x 1 mm in diameter. On post-operative days 7, 14, 28 and 60, histological tissue samples were removed, prepared by fixation and staining, and analyzed by light microscopy. PLAGA matrices produced mild inflammatory reactions and were completely degraded at the end of 60 days, leaving implant tissues that were similar to surgical wounds without implants. TMA-gly:CPH (10:90 and 30:70) matrices produced mild inflammatory reactions by the end of 60 days, similar to those seen with PLAGA. TMA-gly: CPH (50: 50) produced moderate inflammatory reactions characterized by macrophages and edema. PMA-ala:CPH matrices elicited minimal inflammatory reactions that were characterized by fibrous encapsulation by the end of 60 days. In vivo degradation rates of poly(anhydride-co-imides) were similar to PLAGA. Both PMA-ala:CPH and TMA-gly: CPH matrices maintained their shapes and degraded at a constant rate over the period of two months. These polymers, possessing good mechanical properties and tissue compatibility, may be useful in weight-bearing applications in bone.  相似文献   

2.
Serum samples from 1,264 feral pigs from Ossabaw Island, Georgia were initially screened for antibodies to Toxoplasma gondii by the modified agglutination test (MAT) using whole-formalinized tachyzoites and mercaptoethanol. Seropositive samples were also tested by the Sabin-Feldman dye test, the latex agglutination test (LAT), and the indirect hemagglutination test (IHAT). Ossabaw Island is a remote, barrier island located southeast of Savannah, Georgia. Antibodies to T. gondii were found in 11 (0.9%) of 1,264 pigs. The antibody titers were 1:20 (1 pig), 1:80 (2 pigs), 1:160 (2 pigs), 1:320 (4 pigs), and 1:640 (2 pigs) by the MAT, and 1:8 (2 pigs), 1:16 (3 pigs), 1:32 (1 pig), 1:64 (2 pigs), 1:128 (1 pig), and > or = 1:256 (2 pigs) by the Sabin-Feldman dye test. By the LAT, 5 pigs had a titer of > or = 1:64 and by the IHAT all 11 pigs had a titer of < 1:64. Antibodies (MAT titer, > or = 1:25) were found in 31 (18.2%) of 170 feral pigs from mainland Georgia. This seroprevalence on the mainland was significantly higher (P < 0.0001) as compared on Ossabaw Island. The markedly low prevalence of T. gondii on Ossabaw Island was attributed to the virtual absence of cats on the Island; only 1 domestic cat was known to be present.  相似文献   

3.
Thin-layer chromatographic (TLC)-UV densitometric and gas-chromatographic-mass spectrometric detection (GC-MSD) methods were developed for simultaneous quantification of morphine and codeine in poppy capsules (Papaver somniferum). Morphine and codeine were isolated by extraction with chloroform: isopropanol (3:1, v/v) at pH = 8.5 and by solid-phase extraction on Snap-Cap cartridges at pH = 8.5. The TLC-UV densitometric quantification was performed by external standard method on silica gel plates using ethyl acetate: toluene: methanol: ammonia (68:17:10:5, v/v) as developing solvent and UV detection at 275 nm. For the GC-MSD analysis, the drugs were derivatized with acetic anhydride: pyridine (1:1, v/v) and separated on a 30 m HP5 capillary column. The quantification was performed using nalorphine as internal standard.  相似文献   

4.
OBJECTIVES: To compare validation of reported dietary intakes from weighed records against urinary nitrogen excretion and energy expenditure measured by DLW, and to examine the utility of the Goldberg cut-off for EI:BMR in the identification of under-reporters. DESIGN: Energy (EI) and nitrogen (protein) intake (NI) were measured by 16 d of weighed diet records collected over 1 y. They were validated against urinary nitrogen excretion in 5-8 (mean 6.0) 24 h urine collections and total energy expenditure (EE) measured by doubly labelled water (DLW). Basal metabolic rate (BMR) as measured by whole body calorimetry in women or bedside ventilated hood (Deltatrac) in men. Individual subjects were identified as under-reporters if Urine N:NI was > 1.00 or if EI:EE was < 0.79. The agreement between the two ratios in detecting under-reporting was examined. The results from the direct validation by DLW were also compared with validation using the Goldberg cut-off for EI:BMR (Goldberg et al, 1991). SUBJECTS: Eighteen women aged 50-65 y and 27 men aged 55-87 y were selected from participants in two larger dietary surveys as representing the full range of dietary reporting as measured by Urine N:NI. Data from a previous study of 11 post-obese subjects were also included. RESULTS: The two ratios, Urine N:NI and EI:EE, were significantly related (r = -0.48, P < 0.01). Using the above cut-offs, seven (4F, 3M) subjects were identified as under-reporters by both methods, one (1M) by Urine N:NI only and 8 (3F, 5M) by EI:EE only. There was close agreement in post-obese subjects where 6 subjects showed a substantial degree of under-reporting by both methods (r = -0.87, P < 0.001). The correlation between direct validation by DLW and EI:BMRest was 0.65 (P < 0.001). Some limitations of the Goldberg cut-off for identifying individual under-reporters were demonstrated. CONCLUSIONS: EI:EE provides an estimate of the degree of under-reporting of energy at the group and individual level. Urine N:NI identifies under-reporting of protein intake and the most obvious under-reporters of energy, but is probably of lesser value in estimating the overall degree of under-reporting of energy at group level. Good validation by EI:BMR depends on knowledge of physical activity at both group and individual level. However, the correlation of 0.65 between EI:EE and EI:BMRest suggests that EI:BMR could be usefully incorporated into analysis of data from epidemiological studies. Validation measures consisting of at least predicted EI:BMR ratios and urinary measures should be incorporated into dietary surveys. SPONSORSHIP: This work was funded by the Ministry of Agriculture Fisheries and Food, the Medical Research Council, the Cancer Research Council and the Swedish Medical Research Council and the Henning and Johan Throne-Holst Foundation.  相似文献   

5.
Chloroform, the predominant constituent of solvents used for lipid extraction and chromatography, is believed to give rise to birth defects and serious damage to health, and may also be carcinogenic. Therefore, simple and successful methods have been developed to replace chloroform throughout the isolation of glycosphingolipids (GSLs) by less harmful solvents. Gangliosides of sheep brain (ganglio-series gangliosides GM1, GDla, GD1b and GT1b) and of lymphocyte-derived mouse hybridoma cells (namely GM3) were extracted with six different solvent mixtures. Chloroform:methanol:water (40:80:30, v/v/v) was employed as reference (solvent I). Combinations without chloroform were: n-propanol:water (40:10, v/v) (II), methylisobutylketone:methanol:water (40:80:30, v/v/v) (III), ethylacetate:methanol:water (40:72:28, v/v/v) (IV), methylacetate:methanol:water (40:72:28, v/v/v) (V) and petroleum ether:isopropanol:water (40:112:38, v/v/v) (VI). After extraction and dialysis, the weight of lipid extract as well as the content of sialic acid, gangliosides, sulphatides and phospholipids were determined. Quantitation of GSL yields in crude extracts obtained by the alternative solvent mixtures II to VI showed recoveries of brain gangliosides from nearly 67% up to 104% compared with the reference solvent I. Extraction of hybridoma cells by means of the alternative combinations without chloroform revealed at least the same and mostly better ganglioside yields in the range from 98% to 116% with regard to the reference solvent I. n-Propanol:water (II) and methylisobutylketone:methanol:water (III) were the recommended extractants for both tissues. Therefore, the methods described offer simple, less hazardous and successful strategies for GSL extraction in excellent yield without the need for using chloroform.  相似文献   

6.
OBJECTIVE: To evaluate a technique of lateral ovarian transposition by laparoscopy. DESIGN: Case report. SETTING: Tertiary care center. PATIENT(S): A 34-year-old woman with rectal carcinoma. INTERVENTION(S): Laparoscopic ovarian transposition. MAIN OUTCOME MEASURE(S): Return of normal menstruation after irradiation. RESULT(S): Lateral ovarian transposition could be done by laparoscopy. However, division of the ovarian ligament was needed. The location of the ovaries after surgery was outside the radiation field. CONCLUSION(S): Lateral ovarian transposition can be done by laparoscopy. Contrary to a previous report, division of the ovarian ligament is required.  相似文献   

7.
Thermochemical studies on complex of [Sm(o-NBA)_3phen]_2   总被引:1,自引:0,他引:1  
A ternary complex [Sm(o-NBA)3phen]2 (o-NBA: o-Nitrobenzoate; phen: 1,10-phenanthroline) was synthesized and characterized by elemental analysis, IR, molar conductance, and thermogravimetric analysis. The dissolution enthalpies of SmCl3·6H2O(s), o-HNBA(s) and phen·H2O(s) in mixed solvent (VHCl :VDMF :VDMSO=2:2:1) were determined by calorimetry at 298.15 K. The enthalpy change of the reaction was determined to be rHmΔθ=252.49±1.60 kJ/mol. Using the relevant data in the literature and a thermochemical recycle according to Hess’s Law, the standard molar enthalpy of formation of [Sm(o-NBA)3 phen]2 (s) was estimated to be f mHΔθ=–4109.2±7.3 kJ/mol.  相似文献   

8.
Unsaturated fatty acids of odd carbons, 13:1(12), 17:1(10trans), 19:1(7) and 19:1(10) inhibited release of myeloperoxidase (MPO) from fMet-Leu-Phe-cytochalasin B-treated neutrophils. The inhibitory effect was smaller than that of aseanostatins which have been isolated as microbial-derived free fatty acids with a methyl blanch (i-14:0 and ai-15:0) (Journal of Antibiotics (1991) 44, 524-532). These unsaturated fatty acids also inhibited lactoferrin release by the same treatment. On the other hand, 13:1(12), 15:1(10) and 19:1(10) inhibited fMet-Leu-Phe-stimulated superoxide generation of neutrophils, and the fatty acids 15:1(10), 17:(10) and 19:2(10,13) induced superoxide generation in both unstimulated cells and the cell-free system. However, none of unsaturated fatty acids of odd carbons tested inhibited beta-glucuronidase release, whereas 15:1(10), 17:1(10), 19:1(10) and 19:2(10,13) rather enhanced an increase in beta-glucuronidase activity liberated from cells at high concentrations over 35 microM, indicating cellular damages by these fatty acids. These observations suggest that unsaturated free fatty acids having odd carbons such as 13, 15, 17 and 19 may act as modulators of neutrophil functions including degranulation and superoxide generation.  相似文献   

9.
PURPOSE: To compare the accuracy and precision of the elevation topography from two commercially available instruments using videokeratoscopy or rasterstereography. SETTING: University of Ottawa Eye Institute, Ottawa General Hospital, Ontario, Canada. METHODS: Repeated measurements of elevation topography of six calibrated surfaces were done with the PAR Corneal Topography System (CTS) and the Tomey Topographic Modeling System (TMS-1). The shapes simulated normal (A: aspheric, B: spherocylindric) and postsurgical corneas (C: hyperopic, D: myopic, E: central island, F: phototherapeutic keratectomy). Surface shapes were described by parametric equations. Equation parameters associated with each elevation measurement were determined by best-fit analysis. Measurement precision was assessed by the standard deviation of the difference between the fitted and the measured data. Fitted parameters were compared with nominal values obtained from an independent calibration of each surface. The root mean square error (RMSE) of the deviation of the fitted from the nominal surfaces was used to evaluate the accuracy of each instrument. RESULTS: The accuracy of the CTS exceeded that of the TMS-1 for all surfaces measured. The RMSE values (micron) were (A: 0.1, 6.5), (B: 0.3, 3.8), (C: 1.1, 11.8), (D: 5.0, 43.0), (E: 1.2, 3.2) and (F: 2.2, 17.5) for the CTS and TMS-1, respectively. The differences in the measured data from the fit surface were generally smaller with the TMS-1. CONCLUSION: Quantitative analysis of elevation measurements showed that the CTS represented surface topography more accurately than the TMS-1.  相似文献   

10.
The lipopolysaccharide from Klebsiella oxytoca rough mutant R29 (O1-/K29-) has been isolated and its complete structure has been elucidated by compositional analyses, NMR spectroscopy, and laser-desorption mass spectrometry. The carbohydrate backbone has the structure [formula: see text] of which the GlcN residues (the lipid A backbone) are acylated by 14:(3-OH) (amide-linked) and 12:0, 14:0(3-OH)(ester-linked) fatty acids.  相似文献   

11.
The antichlamydial effects of several fatty acids and monoglycerides were studied by incubating Chlamydia trachomatis bacteria with equal volumes of lipid solutions for 10 min and measuring the reduction in infectivity titer compared with that in a control solution without lipid. Caprylic acid (8:0), monocaprylin (8:0), monolaurin (12:0), myristic acid (14:0), palmitoleic acid (16:1), monopalmitolein (16:1), oleic acid (18:1), and monoolein (18:1) at concentrations of 20 mM (final concentration, 10 mM) had negligible effects on C. trachomatis. In contrast, lauric acid (12:0), capric acid (10:0), and monocaprin (10:0) caused a greater than 10,000-fold (>4-log10) reduction in the infectivity titer. When the fatty acids and monoglycerides were further compared at lower concentrations and with shorter exposure times, lauric acid was more active than capric acid and monocaprin was the most active, causing a greater than 100, 000-fold (>5-log10) inactivation of C. trachomatis at a concentration of 5 mM for 5 min. The high levels of activity of capric and lauric acids and particularly that of monocaprin are notable and suggest that these lipids have specific antichlamydial effects. The mode of action of monocaprin was further studied by removal of the lipid by centrifugation before inoculation of Chlamydia onto host cells and by electron microscopy. The results indicate that the bacteria are killed by the lipid, possibly by disrupting the membrane(s) of the elementary bodies. A 50% effective concentration of 30 microgram/ml was found by incubation of Chlamydia with monocaprin for 2 h. The rapid inactivation of large numbers of C. trachomatis organisms by monocaprin suggests that it may be useful as a microbicidal agent for the prevention of the sexual transmission of C. trachomatis.  相似文献   

12.
OBJECTIVES: To compare the long term metabolic effects of two diets for treating hyperlipidaemia. DESIGN: Randomised controlled study: after three weeks of normal (control) diet, subjects were randomly allocated to one of two test diets and followed up for six months. SETTING: Lipid clinic of tertiary referral centre in Naples. SUBJECTS: 63 subjects with primary type IIa and IIb hyperlipoproteinaemia entered the study, and 44 completed it. Exclusion criteria were taking drugs known to influence lipid metabolism, evidence of cardiovascular disease, homozygous familial hypercholesterolaemia, and body mass index over 30. INTERVENTIONS: Two test diets with reduced saturated fat (8%) and cholesterol (approximately 200 mg/day): one was also low in total fat and rich in carbohydrate and fibre, and the other was low in carbohydrate and fibre and rich in polyunsaturated and monounsaturated fats. MAIN OUTCOME MEASURES: Fasting plasma lipid and lipoprotein concentrations; blood glucose, insulin, and triglyceride concentrations before and after a test meal. RESULTS: In comparison with the control diet, both test diets induced significant and similar decreases in low density lipoprotein cholesterol concentrations (by a mean of 0.72 (SE 0.15) mmol/l, P < 0.001, for low total fat diet; by 0.49 (0.18) mmol/l, P < 0.05, for high unsaturated fat diet) and plasma triglyceride concentrations (by 0.21 (0.09) mmol/l, P < 0.05, for low total fat diet; by 0.39 (0.15) mmol/l, P < 0.05, for high unsaturated fat diet), while high density lipoprotein cholesterol concentrations after fasting and plasma glucose and insulin concentrations during test meals were not modified by either diet. CONCLUSIONS: Both test diets are suitable (alone or in combination) for treatment of hypercholesterolaemia.  相似文献   

13.
OBJECTIVE: To assess management of penetrating internal carotid artery (ICA) injuries. DESIGN: Retrospective review of institutional protocol. SETTING: Level 1 trauma center in a major urban area. PATIENTS: Sixty-one patients with penetrating ICA injuries. INTERVENTIONS: In the period 1975 to 1987 (group 1; n = 36), management was based on individual surgeons' preferences. Between 1988 and 1995 (group 2; n = 25), an algorithm was employed: (1) hemodynamically stable patients with suspected ICA injuries underwent a diagnostic angiography; (2) surgically accessible injuries were reconstructed regardless of neurologic status with 2 exceptions: (a) neurologically intact patients with ICA occlusion were treated by anticoagulation and mild pharmacological hypertension and (b) minimal nonocclusive injuries were managed nonoperatively and followed up by serial angiography or duplex ultrasonography; and (3) heparinization, shunting, and completion angiography were employed. MAIN OUTCOME MEASURES: Neurologic status at admission and discharge were compared by the Fisher exact test. RESULTS: In group 1, 24 patients (67%) presented neurologically intact, and 12 (33%) with a deficit. Sixteen injuries were managed nonoperatively, 14 were repaired, and 6 were ligated. At discharge 6 (17%) were improved, 24 (66%) were unchanged, 6 (17%) were worse. Four patients (11%) died of cerebrovascular causes. In group 2, 19 patients (76%) presented neurologically intact, and 6 (24%) with a deficit. Eleven injuries were managed nonoperatively, 12 were repaired, and 2 were ligated. A death occurred in a patient who arrested, was admitted to the hospital in a coma, and died before ICA repair. CONCLUSIONS: Neurologic outcome after ICA injury is enhanced by an algorithm predicated on the liberal use of angiography, a predefined surgical approach, and selective observation.  相似文献   

14.
Europium doped MBrCl (M=Ca, Sr, and Ba) phosphors were prepared by solid state reaction in reductive atmosphere. Photolu-minescence (PL), photostimulated luminescence (PSL) after X-ray irradiation and optical absorption studies of MBrCl:Eu2+ (M=Ca, Sr, and Ba) revealed that: (1) blue light emission, under the excitation of 300 nm, was observed in all these phosphors; (2) the shape of the emission spectra in CaBrCl:Eu2+ could be changed by varying the bromine/chlorine ratio during synthesis, while that in SrBrCl:Eu2+ and BaBrCl:Eu2+ showed no change; and (3) PSL was observed in SrBrCl:Eu2+ and BaBrCI:Eu2+ after X-ray irradiation. Difference absorption spectrum (DAS) in SrBrCl:Eu2+ showed two broad bands centered at about 470 and 570 nm, and DAS in BaBrCI:Eu2+ showed two bands at about 550 and 675 nm, respectively. This enabled the use of He-Ne laser (633 nm) or even semiconductor light-emitting diodes (LED) instead of gas lasers for photostimulation.  相似文献   

15.
200 male undergraduates heard audiotaped counselor–client interactions that culminated in a decision by the counselor to breach or maintain confidentiality. In a control condition no confidentiality manipulation was presented. The degree of seriousness of the client's problem was manipulated in addition to the level of counselor experience, type of presenting problem, and counselor. Ss were randomly assigned to 1 of 48 cells defined by a 3 (confidentiality: confidential, nonconfidential or control) by 2 (problem seriousness: highly or moderately serious) by 2 (counselor experience: expert or nonexpert) by 2 (presenting problem: suicide or drug abuse) by 2 (counselor: A or B) between-Ss factorial design. Among other measures Ss rated counselors on trustworthiness on the Counselor Rating Form. A Confidentiality?×?Problem Seriousness Interaction indicated that with highly serious client problems breaching confidentiality was associated with significantly lower trustworthiness ratings compared to all other conditions. (11 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

16.
In 2 experiments rats were trained on a switching discrimination, with 4 occasion setters, A, B, C, and D and 2 target stimuli, x and y. When signaled either by A or by B, x was reinforced with food and y was not, whereas when signaled either by C or by D these reinforcement relations were reversed (i.e., A: → x+, A: y → ?, B: x → +, B: y → ?, C: x → ?, C: y → +, D: x → ?, D: y → +). In a subsequent Stage A was paired with shock, and then the degree to which food–reinforced (Experiment 1a) and nonreinforced (Experiment 1b) presentations of x and y were capable of eliciting fear was assessed. Those conditioned stimulus (CS)/unconditioned stimulus (US) relations that had been operative in the presence of the fear-eliciting occasion setter A (i.e., x → +, y → ?) elicited more fear than the alternative CS/US combinations (i.e., x → ?, y → +). The implications of these findings are discussed with reference to theories of occasion setting and of configural learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

17.
以Ti、Al、C、TiC粉末为原料,研究掺杂Si及Al含量对自蔓延高温合成Ti3AlC2的影响,合成材料的X射线衍射仪(XRD)及扫描电子显微镜(SEM)分析结果表明:物质的量比n(Ti)∶n(Al)∶n(C)∶n(TiC)∶n(Si)=2∶1.2∶1∶0.9∶0.1的原始混合粉末,经50 MPa压力压制的压坯在空气中...  相似文献   

18.
OBJECTIVE: To evaluate the outcome of intracytoplasmic sperm injection (ICSI) with sperm obtained by electroejaculation in men with psychogenic anejaculation. DESIGN: Retrospective clinical study. SETTING: In Vitro Fertilization Unit, Bikur Cholim Hospital, Jerusalem, Israel. PATIENT(S): Seven men with psychogenic anejaculation who underwent 16 sessions of electroejaculation in combination with ICSI. INTERVENTION(S): Electroejaculation, ICSI. MAIN OUTCOME MEASURE(S): Semen analysis, ICSI, fertilization rates. RESULT(S): All patients had poor sperm motility. One hundred forty-seven oocytes were injected, with a fertilization rate of 27% (39/142). One ongoing pregnancy was achieved. CONCLUSION(S): Sperm obtained by electroejaculation have low motility and reduced fertilization potential. Nevertheless, ICSI should be offered to improve the possibility of successful pregnancy.  相似文献   

19.
OBJECTIVE: The purpose of this study was to find how closely a near infrared instrument (IRI), Futrex 5000, would compare to whole body counting (WBC) of potassium-40 (40K) in assessing body composition. DESIGN: We measured lean body mass (LBM) and percent total body fat (PCF) in 177 males and 27 females by total body potassium (TBK) and by infrared interactance (IRI). TBK was assessed by 2 pi whole body counter (WBC) and IRI by Futrex (F) instrument. These subjects were measured for TBK and for IRI within 1 week of each other. RESULT: A large mean difference (p < or = 0.001) was found between the results using the two instruments: IRI data for LBM were higher and PCF lower compared to TBK. CONCLUSION: As shown by repeated TBK measurements over a 22-year period in these same volunteers, this technique is reliable. The IRI assessments did not come to a close fit with TBK.  相似文献   

20.
PURPOSE: To compare field measures of average daily energy expenditure (ADEE) against criterion data by the doubly labeled water method (DLW) in overweight women. METHODS: The subject were 20 overweight (BMI 29.9 +a- 3.0 kg.m-2) premenopausal women. Energy expenditure was measured by DLW and by the factorial method (activity diary, two techniques differing by method to obtain resting energy expenditure, REE), heart-rate monitoring (HR, two techniques differing by the FLEX-point to discriminate sedentary and activity HR), accelerometer, and pedometer. RESULTS: The ADEE(DLW) was 10.26 +a- 1.1 MJ.d-1. The mean bias (ADEE by the alternative minus ADEE(DLW) was smallest for the accelerometer (+ 0.08 +a- 1.63 MJ) and HR-FLEX10 (+ 0.11 +a- 1.67 MJ). The HR-FLEX(0) technique (lower FLEX-point) overestimated ADEE by + 1.18 (+a- 1.97 MJ). However, the random error (SD of bias) was smaller for both factorial techniques (REE measured: -0.48 +2- 0.81 MJ; REE calculated from the WHO equation: -0.22 +2- 0.88 MJ). CONCLUSION: The results show that simple factorial methods may assess ADEE with small random errors in population with a rather narrow range of physical activity. The accelerometer and HR with the higher FLEX-point have comparable results with smaller bias but larger random error compared with the factorial techniques.  相似文献   

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