首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
ObjectivesSkin tattoos have been shown to reduce localised sweat rate and increase sweat sodium concentration ([Na+]) when sweating is artificially stimulated. This study investigated whether similar responses are observed with exercise-induced sweating.DesignUnblinded, within-participant control, single trial.MethodsTwenty-two healthy individuals (25.1 ± 4.8 y (Mean ± SD), 14 males) with a unilateral tattoo ≥11.4 cm2 in size, ≥2 months in age, and shaded ≥50% participated in this investigation. Participants undertook 20 min of intermittent cycling (4 × 5 min intervals) on a stationary ergometer in a controlled environment (24.6 ± 1.1 °C; 64 ± 6% RH). Resultant sweat was collected into absorbent patches applied at two pairs of contralateral skin sites (pair 1: Tattoo vs. Non-Tattoo; pair 2: Control 1 vs. Control 2 (both non-tattooed)), for determination of sweat rate and sweat [Na+]. Paired samples t-tests were used to determine differences between contralateral sites.ResultsTattoo vs. Non-Tattoo: Neither sweat rate (Mean ± SD: 0.92 ± 0.37 vs. 0.94 ± 0.43 mg·cm−2·min−1, respectively; p = 0.693) nor sweat [Na+] (Median(IQR): 37(32–52) vs. 37(31–45) mM·L−1, respectively; p = 0.827) differed. Control 1 vs. Control 2: Neither sweat rate (Mean±SD: 1.19 ± 0.53 vs. 1.19 ± 0.53 mg·cm−2·min−1, respectively; p = 0.917) nor sweat [Na+] (Median(IQR): 29(26–41) vs. 31(25–43) mM·L−1, respectively; p = 0.147) differed. The non-significant differences for sweat rate and [Na+] between Tattoo vs. Non-Tattoo were inside the range of the within participant variability (sweat rate CVi = 5.4%; sweat [Na+] CVi = 4.4%).ConclusionsSkin tattoos do not appear to alter the rate or [Na+] of exercise-induced sweating. The influence of skin tattoos on localised sweat responses may have previously been over-estimated.  相似文献   

2.
ObjectiveTo compare the effectiveness of the prostate specific antigen (PSA) test and the acid phosphatase (AP) test for semen detection in human vaginal samples.Material and methodThe source materials were vaginal swabs that were tested at Ramathibodi Hospital between 2008 and 2010 from 2450 cases of raped women. Each swab was tested for semen by three methods: sperm detection by light microscopy, the AP enzymatic reaction, and the presence of PSA by using an immuno-chromatographic rapid kit test. The efficiencies of the AP and PSA tests were compared using the light microscopy result for the presence of sperm as the gold standard.ResultThe specificities of the AP, the PSA and the combined AP-PSA tests were 96.4%, 92.3% and 91.9%, respectively, and the sensitivities were 65.5%, 80.4% and 84.5%, respectively. The receiver operating characteristic (ROC) area of the AP, PSA and combined AP-PSA tests were 0.8091, 0.8639 and 0.8823, respectively. The ROC area of the PSA test was significantly greater than that of the AP test (p < 0.0001), and the ROC area of the combined AP-PSA test was significantly greater than both the tests individually (p < 0.0001).DiscussionBased on the ROC area, the PSA test was better than the AP test for semen detection in the vaginal swabs, and the combined results (AP + PSA) were better than the individual tests. The specificity of the AP test was higher than the PSA test in this study because a positive detection was made within only 15 s. While the PSA test was more convenient as it was available in a rapid test kit format, our recommendation is PSA detection should be done together with AP test and spermatozoa examination to identify evidence of rape.ConclusionUsing these three tests together (AP, PSA, and spermatozoa detection) was recommended as a forensic tool for investigations of vaginal swabs of the rape victims.  相似文献   

3.
Third level dermatoglyphic markers show a high level of individuality. Despite this fact, the occurrence of individual sweat pore types is still insufficiently studied due to their problematic extraction. The aim of our study was to evaluate the variability of sweat pore types on distal fingertips in the Slovak population and to establish the most uniform method for delineating the evaluated fingerprint area of 1 cm2 in size to avoid bias in the obtained data. In this study, the variability of seven sweat pore types (round, rhomboid, elliptical, square, rectangular, triangular, hexagonal) on distal phalanges were investigated in a sample of 60 volunteers (30 females and 30 males) from the Slovak population. The evaluated area was 1 cm2. Since none of the previously used definition methods seems to be completely reliable, we developed our own method using individual types of dermatoglyphic patterns. This method allowed an uniform location of the studied fingerprint area. The results suggest that sweat pores, like other dermatoglyphic characteristics, have strong identification potential. Several statistically significant bilateral and intersexual differences were found in both male and female populations. Significant intersexual differences in all categories were found in rhomboid and rectangular sweat pore types. Their use could be applied to partial or otherwise unusable fingerprints. The results of this study could help to incorporate these prints into the identification process, allowing their full use.  相似文献   

4.
5.
This study presents a retrospective performance evaluation of an on-site oral fluid drug screening device DrugWipe® 5/5+ (Securetec). The results obtained by the device were compared with gas chromatography–mass spectrometry confirmation analysis results in whole blood. Data used in the comparison were based on 1,807 real cases in which the Finnish police had conducted an on-site drug test on persons suspected of driving under the influence of drugs. The present data cover only cases wherein the DrugWipe device has shown a positive result for at least one substance. The data were compiled from the databases of Alcohol and Drug Analytics Unit at the National Institute for Health and Welfare. The performance of the DrugWipe was evaluated for its relevant drug groups: amphetamines, cannabis, opiates, and cocaine. The evaluation was carried out by calculating the sensitivity, specificity, and accuracy as well as the positive and negative predictive values. These calculations were based on the classification of the results as true positives, false positives, true negatives, and false negatives. Additionally, the demographics of the cases and analytical findings in whole blood are discussed. According to this study, the DrugWipe device performed quite well in detecting amphetamines, the most frequently encountered group of illicit drugs in Finnish traffic. The performance of the cannabis, opiate, and cocaine tests was not at the same level.  相似文献   

6.
PURPOSE: This study examined the impact of 10 d of exercise-heat acclimation on sweat mineral concentrations. METHODS: Eight male subjects walked on a treadmill at 3.5 mph, 4% grade for 100 continuous minutes or until rectal temperature reached 39.5 degrees C on 10 consecutive days in an environmental chamber set at 45 degrees C, 20% relative humidity. Arm sweat samples were collected during the first 30 min of exercise-heat stress on days 1 and 10 using a polyethylene arm glove. RESULTS: Final core temperature and HR values were significantly lower (P < 0.05) on day 10 versus day 1. Whole-body sweating rates increased by approximately 6% (P = 0.12). Sweat sodium concentration on day 10 (36.22 +/- 7.22 mM) was significantly lower than day 1 (54.49 +/- 16.18 mM) (P < 0.05). Sweat mineral concentrations of calcium (approximately 29%), copper (approximately 50%), and magnesium (approximately 43%) were also significantly lower on day 10 versus day 1 of heat acclimation (P < 0.05). A trend for lower sweat iron (approximately 75%; P = 0.07) and zinc (approximately 23%; P = 0.10) concentrations were observed from day 1 to day 10. The estimated hourly sweat mineral losses (arm concentration x whole-body sweat rate) were reduced for calcium (approximately 27%), copper (approximately 46%), and magnesium (approximately 42%) (P < 0.05), but not iron (75%) or zinc (approximately 16%) (P > 0.05), from day 1 to day 10. CONCLUSION: Exercise-heat acclimation conserves arm sweat mineral concentrations and possibly whole-body sweat losses of calcium, copper, and magnesium, and may reduce sweat iron and zinc concentrations.  相似文献   

7.
Identification of body fluids is a common task in medico-legal practice, but specific markers for sweat have not been identified to date. To develop a method for identification of sweat, we identified a sweat-specific protein and produced monoclonal antibodies by immunizing mice with sweat proteins fractionated by anion-exchange chromatography. Among many sweat-reactive monoclonal antibodies obtained, one monoclonal antibody (G-81) was selected because of its unique specificity. G-81 reacted to sweat but not to other body fluids (e.g. serum, saliva, semen, milk, urine and tears) in ELISA. G-81 specifically stained the eccrine sweat gland and did not stain any other tissue including the apocrine sweat gland. In western blotting, G-81 reacted strongly to a 7 kDa band and faintly to 20, 27 and 33 kDa bands of sweat protein. The N-terminal amino acid sequence (18 amino acids) of G-81-reactive peptides was determined, and an identical sequence was found in an antibiotic peptide dermcidin (110 amino acids) reported recently, suggesting that G-81 recognized a fragment of dermcidin. The G-81-reactive peptide could be detected in 8,192-fold dilutions of sweat by ELISA and could be detected in 200-fold diluted sweat samples ( n=26) independent of the protein concentration. The G-81-reactive peptide was very stable and was able to detect sweat stains left for at least 11 weeks at room temperature without substantial loss of reactivity. These facts suggest that G-81 is a very useful tool for sweat identification in medico-legal practice.  相似文献   

8.
《Radiography》2022,28(2):466-472
IntroductionScreening for metallic implants and foreign bodies before magnetic resonance imaging (MRI) examinations, are crucial for patient safety. History of health are supplied by the patient, a family member, screening of electronic health records or the picture and archive systems (PACS). PACS securely store and transmits digital radiographs (DR) and related reports with patient information. Convolutional neural networks (CNN) can be used to detect metallic objects in DRs stored in PACS. This study evaluates the accuracy of CNNs in the detection of metallic objects on DRs as an MRI screening tool.MethodsThe musculoskeletal radiographs (MURA) dataset consisting of 14.863 upper extremity studies were stratified into datasets with and without metal. For each anatomical region: Elbow, finger, hand, humerus, forearm, shoulder and wrist we trained and validated CNN algorithms to classify radiographs with and without metal. Algorithm performance was evaluated with area under the receiver-operating curve (AUC), sensitivity, specificity, predictive values and accuracies compared with a reference standard of manually labelling.ResultsSensitivities, specificities and area under the ROC-curves (AUC) for the six anatomic regions ranged from 85.33% (95% CI: 78.64%–90.57%) to 100.00% (95% CI: 98.16%–100.00%), 75.44% (95% CI: 62.24%–85.87%) to 93.57% (95% CI: 88.78%–96.75%) and 0.95 to 0.99, respectively.ConclusionCNN algorithms classify DRs with metallic objects for six different anatomic regions with near-perfect accuracy. The rapid and iterative capability of the algorithms allows for scalable expansion and as a substitute MRI screening tool for metallic objects.Implications for practiceAll CNNs would be able to assist in metal detection of digital radiographs prior to MRI, an substantially decrease screening time.  相似文献   

9.
《Brachytherapy》2022,21(4):487-493
MethodsThis retrospective study evaluated patients who received three-fraction accelerated partial breast irradiation (APBI) via brachytherapy for breast cancer between January 2016 and April 2020. Inclusion criteria included age ≥18 years and early-stage unilateral breast cancer with negative lymph nodes. We evaluated acute toxicity (<6 weeks), late toxicity (≥6 weeks), and cosmetic outcomes. Frequencies of each variable were calculated. Cancer-specific outcomes were determined via the Kaplan-Meier method.ResultsThirty consecutive patients received three-fraction APBI of 2,250 cGy over 2 d. All cancers were stage T2 or less. Median time to last follow-up was 22 months. Local recurrence-free survival was 95.8% at 22 months. Seventeen (56.7%) patients reported an acute toxicity event. All were grade 1 except one patient with grade 2 (fatigue). No patient experienced ≥ grade 3 acute toxicity. One (3.3%) patient reported grade 3 late toxicity (tissue fibrosis). No patients had breast edema, fat necrosis, or non-healing wounds. There were no ≥ grade 3 cosmetic events.DiscussionThree-fraction APBI via brachytherapy was successful in preventing disease recurrence and death in this study, with still limited follow-up. Although acute and late toxicities or adverse cosmetic outcomes were seen, very few were grade 2 or higher and compare favorably to those reported in prior 10-fraction APBI studies.ConclusionsThis study provides early single institutional evidence that three-fraction APBI may become a feasible treatment alternative.  相似文献   

10.
《Radiography》2016,22(3):e190-e195
BackgroundMammography is an important screening tool for reducing breast cancer mortality. Digital breast tomosynthesis (DBT) can potentially be integrated with mammography to aid in cancer detection.MethodUsing the PRISMA guidelines, a systematic review of current literature was conducted to identify issues relating to the use of tomosynthesis as a screening tool together with mammography.FindingsUsing tomosynthesis with digital mammography (DM) increases breast cancer detection, reduces recall rates and increases the positive predictive value of those cases recalled. Invasive cancer detection is significantly improved in tomosynthesis compared to mammography, and has improved success for women with heterogeneous or extremely dense breasts.ConclusionTomosynthesis reduces some limitations of mammography at the time of screening that until recently were most often addressed by ultrasound at later work-up. Tomosynthesis can potentially be adopted alongside mammography as a screening tool.  相似文献   

11.
《Radiography》2022,28(4):877-880
IntroductionFat-suppressed images are essential in clinical practice but are often affected by magnetic field inhomogeneity, resulting in poor image quality. We hypothesized that salt (99% sodium chloride [NaCl]) could be used as a magnetic field uniformity assist pad and verified whether salt pads improve magnetic field uniformity and the fat suppression effect in low-field magnetic resonance imaging (MRI) systems.MethodsWe conducted a small clinical study where coronal 2D fast spin-echo T2-weighted MRI with fat suppression was performed. The subjects were 10 healthy volunteers (six men and four women) with no surgical history, with a mean age of 20.5 years (range, 20–30 years). In the clinical study, we performed physical and visual evaluation by imaging a subject's knee with and without salt pads.ResultsThe results of the clinical study indicated that the use of salt pads improved the magnetic field uniformity, thus increasing the fat suppression effect.ConclusionsSalt pads improved the homogeneity of the magnetic field and the fat suppression effect in low-field MRI systems.Implications for practiceThe use of salt pads in low-field MRI systems could provide more accurate fat suppression images.  相似文献   

12.
ObjectiveTo identify the current return-to-work (RTW) screening tests conducted for athletic occupations following injury and their effectiveness of reducing reinjury risk.MethodsA search was made of multiple databases (BioMed Central, CINAHL through ebscohost, EMBASE, Google Scholar, PUBMED, Scopus, SPORTDiscus and Web of Science) from their inception to March 2022, using relevant terms to identify articles meeting predefined inclusion/exclusion criteria. The search, data extraction, risk of bias, and evaluation of the certainty of the findings were completed independently by two authors. To understand the effectiveness of screening tests and their impact in reducing in reinjury rates, results were split into the following three time points: “Short-term” (≤1 year), “Medium-term” (≥2 years) and “Long-term” (≥3 years).ResultsFive studies (n = 507) met the inclusion criteria. There was a very low level of certainty for the effectiveness of screening tools reducing reinjury risk at short-term, medium-term and long-term follow ups. Only one study recorded a large effect in the reducing reinjury risk.ConclusionThe results demonstrated very low level of certainty for the effectiveness of screening tests reducing the risk of reinjury. A gap in our understanding currently exists for the effectiveness of RTW screening tests in tactical athletic occupations following injury and further research investigating is required.  相似文献   

13.
Summary Morphine and methamphetamine, which are excreted in the sweat, are detected by the use of routine serological and physicochemical techniques for urinary examinations. Screening for drug abuse can be done with the same accuracy of that of urine. Rapid excretion of the drug via kidney (within one day) is followed by a slow but steady excretion of the sweat gland. Methamphetamine given orally in a dosis of 10 mg is excreted in the sweat at a constant rate (1.4 g/ml). No significant difference of the amount excreted by both systems is found. Alveolar lining seems to prevent the elimination of the volatile methamphetamine via respiration. Not only narcotics and stimulants, but also many alkaloids and barbiturates are excreted in the sweat and detected quantitatively by the same principles. The toxicological analysis of the sweat promises a new scope of forensic investigation.  相似文献   

14.
《Brachytherapy》2020,19(5):679-684
PurposeIntraoperative radiation therapy (IORT), a form of accelerated partial breast irradiation (APBI), is an appealing alternative to postoperative whole breast irradiation for early-stage breast cancer. The purpose of this study was to examine the toxicity and cosmetic outcomes of patients treated with a novel form of breast IORT (precision breast IORT; PB-IORT), that delivers a targeted, higher dose of radiation than conventional IORT.Methods and MaterialsThe first 204 patients treated with PB-IORT in a Phase II clinical trial (NCT02400658) with 12 months of followup were included. Trial inclusion criteria were age ≥45 years, invasive or in situ breast cancer, tumor size ≤3 cm, and node negative. Toxicity and cosmetic scoring were performed at 6 and 12 months.Results98 patients (48%; 95% CI, 41–55%) experienced toxicity. Seven Grade 3 toxicities occurred (3.4%; 95% CI, 1.4–6.9%). Most patients (95%) had excellent or good cosmetic outcomes (95% CI, 91–98%) at 12 months. Most patients (94%) had little or no pigmentation change (95% CI, 90–97%), 88% little to no size change (95% CI, 82–92%), and 87% experienced minimal shape change (95% CI, 82–92%).ConclusionsOverall, Grade 3+ toxicity was rare and cosmetic outcomes were excellent. Severe toxicity with PB-IORT is similar to that reported in the TARGIT trial (3.3% rate of major toxicity) but lower than APBI (NSABP-39, 10.1% Grade 3/4 toxicities). We propose that the toxicity of PB-IORT compared with TARGIT and NSABP-39 is related to the radiation dose and delivery schedule. PB-IORT offers low-toxicity and good cosmetic outcomes when compared with other forms of APBI.  相似文献   

15.
16.
PurposeTo evaluate efficacy and safety of radiofrequency (RF) ablation for parotid Warthin tumor.Materials and MethodsFrom September 2016 to August 2017, 7 consecutive patients with biopsy-proven parotid Warthin tumors who did not undergo surgery presented with symptoms or cosmetic concerns and underwent US-guided percutaneous RF ablation treatment. RF ablation procedures were performed using the moving shot technique. US, contrast-enhanced CT, or MR imaging was performed 6–12 months after each procedure. Complications and cosmetic scale improvement after RF ablation were also evaluated.ResultsThere was a significant reduction in mean tumor volume from 14.6 cm3 ± 13.1 (range, 1.9–35.5 cm3) to 0.8 cm3 ± 0.5 (range, 0.2–1.54 cm3) and a mean cosmetic scale improvement (from 4 to 1) on imaging studies 6–12 months after RF ablation compared with before RF ablation (P < .05). Volume reduction ratios at 1–2 months, 5–6 months, and 10–12 months after RF ablation were 51.2% ± 18.1%, 87.8% ± 10.6%, and 94.3% ± 2.0%. There was no facial nerve injury. One patient with parotitis and hematoma recovered in 1 week.ConclusionsRF ablation using the moving shot technique could be an effective and safe alternative treatment for parotid tail Warthin tumors in patients unsuitable for or unwilling to undergo surgical resection.  相似文献   

17.
Peripheral sweat rate was measured to determine if acute normobaric hypoxia exerted a local inhibition on sweat gland function. It was hypothesized that peripheral sweat rate would be reduced during hypoxia, following cholinergic stimulation. Nineteen subjects (24 +/- 3 yr; 177 +/- 9 cm; 75.5 +/- 20.1 kg), 8 females and 11 males, were tested once during normobaric hypoxia, simulating an altitude of approximately 3050 m (P(O2) = 13.9%; P(B) approximately 730 mmHg), and once at sea level (200 m; P(O2) = 20.9%; P(B) approximately 730 mmHg). While seated at rest, a approximately 7-cm(2) area of the anterior forearm was stimulated using pilocarpine iontophoresis to produce localized sweating at the site. Following stimulation, sweat was collected from the area for 15 min using a Macroduct Sweat Collection System. One-way repeated measures ANOVA indicated a significantly lower sweat rate during normobaric hypoxia (4.6 +/- 2.6 g x m(-2) x min(-1)) compared to sea level (5.5 +/- 3.0 g x m(-2) x min(-1); p = 0.006). Because sweating was initiated directly at the sweat gland, thus bypassing central nervous system input, changes in sweat rate were likely due to peripheral alterations. Although these peripheral mechanisms warrant further investigation, the results of this study suggest a direct hypoxic influence on sweat gland function as evidenced by a decrease in sweat rate.  相似文献   

18.
IntroductionImaging of gene expression with positron emission tomography (PET) has emerged as a powerful tool for biomedical research during the last decade. The prototypical herpes simplex virus type 1 thymidine kinase (HSV1-TK) PET reporter gene (PRG) is widely used and many other PRGs have also been validated. We investigated varicella zoster virus thymidine kinase (VZV-tk) as new PRG with radiolabeled bicyclic nucleoside analogues (BCNAs) as PET tracers.MethodsThe uptake and washout of four different radiolabeled BCNAs was evaluated in cells expressing VZV-tk after lentiviral vector (LV) transduction and in control cells. Metabolism of the tracers was assayed by high pressure liquid chromatography (HPLC). Mice bearing VZV-TK expressing xenografts were imaged with PET.ResultsHigh uptake in VZV-tk expressing cells was seen for 3 of the 4 tracers tested. The uptake of the tracers could be blocked by the presence of excess thymidine in the incubation solution. Cellular retention was variable, with one tracer showing an acceptable half-life of ~ 1 hour. The amount of intracellular tracer correlated with the titer of LV used to transduce the cells. VZV-TK dependent conversion into metabolites was shown by HPLC. No specific accumulation was observed in cells expressing a fusion protein containing an HSV1-TK moiety. VZV-tk expression in xenografts resulted in a 60% increase in uptake in vivo as measured with PET.ConclusionsWe have validated the combination of VZV-tk and radiolabeled BCNAs as new PRG/PRP system. Further optimization of the PRPs and the PRG are warranted to increase the signal.  相似文献   

19.
PurposeThe ACR developed the Lung CT Screening Reporting and Data System (Lung-RADS) to standardize the diagnostic follow-up of suspicious screening findings. A retrospective analysis showed that Lung-RADS would have reduced the false-positive rate in the National Lung Screening Trial, but the optimal timing of follow-up examinations has not been established. In this study, we assess the effectiveness of alternative diagnostic follow-up intervals on lung cancer screening.MethodsWe used the Lung Cancer Outcome Simulator to estimate population-level outcomes of alternative diagnostic follow-up intervals for Lung-RADS categories 3 and 4A. The Lung Cancer Outcome Simulator is a microsimulation model developed within the Cancer Intervention and Surveillance Modeling Network Consortium to evaluate outcomes of national screening guidelines. Here, among the evaluated outcomes are percentage of mortality reduction, screens performed, lung cancer deaths averted, screen-detected cases, and average number of screens and follow-ups per death averted.ResultsThe recommended 3-month follow-up interval for Lung-RADS category 4A is optimal. However, for Lung-RADS category 3, a 5-month, instead of the recommended 6-month, follow-up interval yielded a higher mortality reduction (0.08% for men versus 0.05% for women), and a higher number of deaths averted (36 versus 27), a higher number of screen-detected cases (13 versus 7), and a lower number of combined low-dose CTs and diagnostic follow-ups per death avoided (8 versus 5), per one million general population. Sensitivity analysis of nodule progression threshold verifies a higher mortality reduction with a 1-month earlier follow-up for Lung-RADS 3.ConclusionsOne-month earlier diagnostic follow-ups for individuals with Lung-RADS category 3 nodules may result in a higher mortality reduction and warrants further investigation.  相似文献   

20.
Objectives:This work establishes the prototype of a new innovative risk model that aims to evaluate the total risk involved with screening mammography for each individual female. This has been specifically designed to accommodate any combination of lifetime screening regimes, using only the information gathered from a single mammographic examination.Methods:This model prototype was developed with the aid of a large dataset of images from the Cancer Institute New South Wales (CINSW) with over 30,000 images from over 7000 examinations. Each examination is derived from a separate female.Results:This prototype which we have called Breast Individualised Risk of Radiation-Induced Screening Cancer (Breast-iRRISC) is a novel tool for the assessment of the lifetime risk involved with screening mammography. The results demonstrate the applicability of this approach to the various screening regimes utilised around the globe, in addition to the personalised screening frequency patterns females have undergone and are likely to receive in the future.Conclusions:This unique tailored approach to risk assessment will further empower females and clinicians towards a more informed clinical decision process regarding future imaging pathways. It will also inform health policy decisions regarding alternate screening durations and intervals.Advances in knowledge:Breast-iRRISC is a novel tool that provides females, clinicians and health policymakers around the globe with the ability to quantify the lifetime risk of radiation-induced breast cancer from screening mammography on an individual level from a single exposure.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号