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1.
Aditoprim (ADP), a new developed dihydrofolate reductase (DHFR) inhibitor, has great potential in clinical veterinary medicine because of its greater pharmacokinetic properties than structural analogs. Preclinical toxicology studies were performed to assess the safety of ADP including an acute oral toxicity test, a subchronic toxicity test and five mutagenicity tests. In the acute oral toxicity test, ADP was administered singly by oral gavage to Wistar rats and Kunming mice. The LD50 calculated was 1400 mg kg–1 body weight (BW) day–1 in rats and 1130 mg kg–1 BW day–1 in mice. In a subchronic study, Wistar rats were administered ADP at dose levels of 0, 20, 100 and 1000 mg kg–1 diet for 90 days. Significant decreases were observed on body weight and food efficiency in the high‐dose group. Treatment‐related changes in clinical serum biochemistry were found in the medium‐ and high‐dose groups. Significant increases in the relative weights of livers and kidneys in females and testis in males in the 1000 mg kg–1 diet, and significant decrease in relative weights of livers in males in the 100 mg kg–1 diet were noted. Histopathological observations revealed that the 1000 mg kg–1 ADP diet could induce lymphocytic infiltration and hepatocytic necrosis near the hepatic portal area. The genotoxicity of ADP was negative in tests, such as the bacterial reverse mutation assay, mice bone marrow erythrocyte micronucleus assay, in vitro chromosomal aberration test, in vitro cho/hgprt mammalian cell mutagenesis assay and mice testicle cells chromosome aberration. Based on the subchronic study, the no‐observed‐adverse‐effect level for ADP was a 20 mg kg–1 diet, which is about 1.44‐1.53 mg kg–1 BW day–1 in rats. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

2.
N-acetylglycine (NAGly) has been identified as a minor constituent of numerous foods. The current paper reports the outcome of in vitro and in vivo genotoxicity, acute oral and repeated dose dietary toxicology studies conducted with NAGly. No evidence of genotoxicity was observed with NAGly in vitro bacterial tester strains or in vivo bone marrow micronucleus studies conducted in mice. No mortalities or evidence of adverse effects were observed in Sprague–Dawley rats following acute oral gavage with NAGly at a dose of 2000 mg/kg of body weight or following repeated dose dietary exposure to NAGly at targeted doses of 100, 500, or 1000 mg/kg of body weight/day for 28 days. No biologically significant or test substance related differences were observed in body weights, feed consumption, or clinical pathology response variables in any of the treatment groups. Based on these results it was concluded that NAGly is not genotoxic or acutely toxic. Further, the no-observed adverse-effect-level (NOAEL) for systemic toxicity from repeated dose dietary exposure to NAGly was 898.9 mg/kg of body weight/day for male rats and 989.9 mg/kg of body weight/day for female rats.  相似文献   

3.
In western Cameroon, edible fruits and seeds from the plant Dichrostachys glomerata are commonly used as spices. Extract from the fruit pods has been reported as a good natural source of antioxidants and may provide health benefits. The objective of the present study was to investigate potential adverse effects, if any, of D. glomerata fruit pod extract (Dyglomera™) in a subchronic toxicity study and in genotoxicity studies. In the toxicity study, Sprague Dawley rats (20/sex/group) were gavaged with D. glomerata extract at dose levels of 0, 100, 1000 and 2500 mg/kg body weight (bw)/day for 90-days. Dyglomera™ administration did not result in mortality or show treatmentrelated changes in clinical signs of toxicity, body weights, body weight gain or feed consumption. Similarly, no toxicologically significant treatment-related changes in hematological, clinical chemistry, urine analysis parameters, and organ weights were noted. Macroscopic and microscopic examinations did not reveal treatment-related abnormalities. Mutagenic and clastogenic potentials as evaluated by Ames assay, in vitro and in vivo chromosomal aberration test and in vivo micronucleus test did not reveal any genotoxicity of the extract. The results of subchronic toxicity study supports the no-observed-adverse-effect level (NOAEL) for D. glomerata extract as 2500 mg/kg bw/day, the highest dose tested.  相似文献   

4.
N-acetyl-glutamic acid (NAG) is an endogenously produced mammalian substance and minor constituent of commonly consumed foods. This paper reports the outcome of genotoxicity and acute and repeated dose (28-day) oral toxicology studies conducted with NAG. No evidence of genotoxicity was observed with NAG in in vitro or in vivo studies. No mortalities or evidence of adverse effects was observed in Sprague–Dawley rats following acute oral gavage with NAG at a dose of 2000 mg/kg of body weight. No adverse effects were observed in rats following repeated dose dietary exposure to NAG at target concentrations corresponding to doses of 100, 500, or 1000 mg/kg of body weight/day for 28 days. All rats survived until scheduled sacrifice and no biologically significant or test substance related differences were observed in body weights, feed consumption, clinical signs, functional observational battery (FOB), ophthalmology, hematology, coagulation, clinical chemistry, organ weights or histopathology of any of the treatment groups. Based on the observed results it is concluded that NAG is not genotoxic or acutely toxic. The no-observed-adverse-effect-level (NOAEL) for systemic toxicity from repeated dose (28-day) dietary exposure to NAG was 914 mg/kg of body weight/day for male rats and 1007 mg/kg of body weight/day for female rats.  相似文献   

5.
Herbal medicines are widely utilized for disease prevention and health promotion. GHX02 consists of mixtures including Gwaruin (Trichosanthes kirilowii), Haengin (Prunus armeniaca), Hwangryeon (Coptis japonica) and Hwangkeum (Scutellaria baicalensis). It has been purported to have therapeutic effectiveness in cases of severe bronchitis. Non-clinical safety testing comprised a single-dose oral toxicity study and a 28-day repeated-dose oral toxicity study with a 14-day recovery period, and genotoxicity was assessed by a bacterial reverse mutation test, in vitro chromosomal aberration test, in vivo mouse bone marrow micronucleus test and single cell gel electrophoresis assay (comet assay). In the single-dose oral toxicity study, the approximate lethal dosage is estimated to be higher than 5000 mg/kg in rats. Thus, the dosage levels were set at 0, 1250, 2500 and 5000 mg/kg/day in the 28-day repeated-dose oral toxicity study, and 10 male rats and 10 female rats/dose were administered GHX02. No clinical signs of toxicological significance were recorded in any animal during the dosing and the observation period in the single-dose study. The no-observed-adverse-effect level of GHX02 was 5000 mg/kg/day when administered orally for 28 days to male and female Sprague-Dawley rats. Despite increases in the frequencies of cells with numerical chromosomal aberration in the in vitro test, the increases were not considered relevant to the in vivo genetic risk. Except for the increase of in vitro numerical chromosomal aberration, clear negative results were obtained from other genetic toxicity studies.  相似文献   

6.
Crystalline β-carotene from genetically modified Yarrowia lipolytica is an alternative source of β-carotene for use as a nutritional supplement. To support the use of β-carotene from Y. lipolytica as a food ingredient, the genotoxic and subchronic toxicity potential of this compound was determined. Genotoxicity was examined using Salmonella typhimurium and Escherichia coli (Ames test), a chromosomal aberration assay in Chinese Hamster Ovary WBL cells, and the micronucleus test in CD-1 mice. All three assays showed no significant results due to β-carotene from Y. lipolytica. In a subchronic toxicity study in SD rats, β-carotene from Y. lipolytica was administered by oral gavage for 13 weeks at 0, 125, 250 or 500 mg/kg per day. Adverse effects were not observed following clinical, clinical pathology and gross- and histopathological evaluations of dosed rats; thus, the no-observed-adverse effect level (NOAEL) for β-carotene from Y. lipolytica was 500 mg/kg, the highest dose used in the study. In conclusion, β-carotene derived from Y. lipolytica was shown in genotoxicity models and a standard rat subchronic rat study to have a safety profile similar to that of the current commercial products (synthetic and natural) with no unexpected finding attributable to the alternative source.  相似文献   

7.
Naringin is widely distributed in plant foods and has not previously been evaluated for safety through standard in vivo toxicological studies. In the present study, acute and subchronic oral toxicity studies of naringin were designed and conducted in Sprague-Dawley (SD) rats. Acute oral administration of naringin was done as a single bolus dose up to 16 g/kg and subchronic toxicity study for 13 weeks was done by oral administration at doses of 0 (control), 50, 250 and 1250 mg/kg in SD rats. There were no mortality, adverse clinical signs, abnormal changes in body weights or food consumption, toxicologically relevant changes in hematology, clinical biochemistry and macroscopic findings during 14 days of the acute toxicity study. During the subchronic oral toxicity study, no mortality and toxicologically significant changes in clinical signs, food consumption, opthalmoscopic examination, hematology, clinical biochemistry, serum sex hormone, macroscopic findings, organ weights and histopathological examination except for slight body weight decrease were noted and attributed to naringin administration. These observations suggest that naringin is practically non-toxic for SD rats in oral acute toxicity study and the no-observed-adverse-effect-level (NOAEL) of naringin in rats is greater than 1250 mg/kg/day when administered orally for 13 consecutive weeks.  相似文献   

8.
Koji products have been considered as an effective fermented food consumed in East Asia with many health benefits. Particularly, rice koji with Aspergillus terreus (RAT) has been reported to be able to prevent hyperlipidemia and hepatic steatosis through regulating cholesterol synthesis. Despite its biological activities, there is a lack of comprehensive information to give an assurance of its safety. Therefore, the objective of this study was to perform a series of toxicological studies (repeated dose oral toxicity and genotoxicity) according to test guidelines published by the Organization for Economic Cooperation and Development. Along with acute toxicity study using rats and beagle dogs, a 13-week toxicity study revealed no clear RAT-related toxic changes, including body weight, mortality, hematology, serum biochemistry, organ weight, and histopathology after oral administration at doses of 500, 1000, and 2000 mg/kg BW. The no-observed-adverse-effect level of RAT was considered to be more than 2000 mg/kg BW/day in rats of both genders. In addition, potential genotoxicity was evaluated using a standard battery of tests (Ames test, chromosome aberration assay, and micronucleus assay) which revealed that RAT showed no genotoxicity. Accordingly, these results suggest that RAT is a safe and non-toxic functional food for human consumption at proper dose.  相似文献   

9.
The safety of enzyme-treated asparagus extract (ETAS) developed as a novel anti-stress functional material was assessed in acute and subchronic studies and genotoxicity assays. In the acute oral dose toxicity study, all rats survived during the test period and ETAS did not influence clinical appearance, body weight gain and necropsy findings at a dosage of 2000 mg/kg body weight. Thus, the 50% lethal dose (LD50) of ETAS was determined to be greater than 2000 mg/kg. The 90-day subchronic study (500, 1000 and 2000 mg/kg body weight, delivered by gavage) in rats reported no significant adverse effects in food consumption, body weight, mortality, urinalysis, hematology, biochemistry, necropsy, organ weight and histopathology. In the micronucleus test of mice, the incidence of micronuclei in ETAS-administered groups (500, 1000 and 2000 mg/kg/day, injected twice) was equivalent to that of the negative control group, while the positive control group receiving mitomycin C showed a high incidence. The potential of ETAS to induce gene mutation was tested using four Salmonella typhimurium strains and Escherichia coli WP2uvrA. The test sample was not mutagenic to the test strains. These results support the safety of ETAS as food and dietary supplement.  相似文献   

10.
Rheum emodi has been used as an edible and medicinal plant in Tibet and Kashmir for a long period of time, while safety evaluation of this plant has not yet been investigated. In this study, acute and subchronic oral toxicity studies of aqueous extract of R. emodi (AERE) rhizome were conducted in SD rats. Animals were treated with a single dose of 1000, 2000, 4000 or 10,000 mg/kg of AERE in the acute toxicity. In subchronic oral toxicity, animals were randomly divided into four groups (10 rats/sex/group) and received doses of 0, 1000, 2000, and 4000 mg/kg/d of AERE for 90 days. Daily clinical observations, weekly measurement of body weight and food consumption were conducted. Blood and urine were collected on days 91 to measure changes. At necropsy, selected organs were weighed and recorded, and histological examination was performed. During the subchronic oral toxicity study, no mortality, obvious treatment-related clinical signs and urinalysis parameters were observed. Differences in weight gain, food consumption, hematology, biochemistry, relative organ weight and histopathology examinations between the treated group and the control group were not considered treatment-related. Our results indicated that the no-observed-adverse-effect level (NOAEL) for AERE was 4000 mg/kg/d in both genders.  相似文献   

11.
African Bush Mango from Irvingia gabonensis is a West African culinary fruit and the mucilage from this fruit seed is used to make traditional soups and sauces. Extract from the kernel (IGOB131) has been claimed for its health benefits. In the present investigations, potential adverse effects, if any, of IGOB131 were investigated in dose–response 90-day study and genotoxicity studies. In the subchronic study, Sprague Dawley rats (20/sex/group) were gavaged with I. gabonensis extract (IGOB131) at dose levels of 0, 100, 1000 and 2500 mg/kg body weight (bw)/day for 90-days. No treatment-related changes in clinical signs, functional observations, mortality, ophthalmologic observations, body weights, body weight gain or feed consumption were noted. Similarly, hematological, clinical chemistry, urine analysis parameters, and organ weights did not reveal any toxicologically significant treatment-related changes. No treatment-related macroscopic and microscopic abnormalities were noted at the end of treatment period. The mutagenicity as evaluated by Ames assay, in vitro and in vivo chromosomal aberration test and in vivo micronucleus assay did not reveal any genotoxicity of IGOB131. The results of subchronic toxicity study suggest the no-observed-adverse-effect level (NOAEL) for I. gabonensis extract (IGOB131) as ?2500 mg/kg bw/day, the highest dose tested.  相似文献   

12.
Adenosine-5′-monophosphate (AMP) deaminase is an enzyme used to increase concentrations of 5’-inosine monophosphate in certain foods and beverages for flavoring purposes. One commercial source of this enzyme is Aspergillus oryzae, a filamentous fungus with a history of safe use in Asia as a fermentation organism used in the production of miso sauce and sake liquors. Noting the use of the enzyme in food intended for human consumption and potential presence at trace levels in finished goods, a series of safety studies including an in vitro Ames test and chromosome aberration assay with Chinese hamster lung fibroblasts were conducted along with a 90-day oral toxicity study in rats. AMP deaminase showed no evidence of genotoxicity in the in vitro tests. Following gavage administration of Sprague–Dawley rats at dosages of 19.8, 198.4, or 1984 mg total organic solids (TOS)/kg body weight (bw)/day for 90 days, no adverse effects on body weight gain, food consumption, hematology, clinical chemistry, urinalysis, ophthalmological and histopathological examinations were observed. The no-observed-adverse-effect level was considered to be 1984 mg TOS/kg bw/day, the highest dose tested. Results of the genotoxicity studies and subchronic rat study support the safe use of AMP deaminase produced from A. oryzae in food production.  相似文献   

13.
Steroidal saponin DT-13 (25 (R, S)-ruscogenin-1-O-[β-d-glucopyranosyl - (1 → 2)] [β-d-xylopyranosyl-(1 → 3)]-β-d-fucopyranoside) is the main active component of the tube of Liriope muscari (Decne.) Baily and has been studied as a candidate drug for cancer metastasis. The objective of this study was to evaluate the safety of DT-13 systematically by genotoxicity and acute oral toxicity and subchronic 90-day oral gavage toxicity. Results of Ames test confirmed that DT-13 did not induce mutations in histidine auxotrophs Salmonella typhimurium (TA 97, TA 98, TA 100 and TA 102) both in the presence and absence of metabolic activation system at the doses of 0.05-500 μg/plate. Meanwhile, DT-13 did not induce clastogenicity at doses of 1250, 2500 and 5000 mg/kg in mouse micronucleus test. And the single oral dose of DT-13 at 5000 mg/kg did not produce mortality or significant changes in the general behavior and gross appearance of the internal organs of mice. In subchronic toxicity study, DT-13 was administrated to Sprague-Dawley rats via oral gavage at doses of 10, 60 and 360 mg/kg for 90 days. Necropsy, hematological and biochemical analysis, and histopathological examination did not reveal any remarkable and treatment related changes. In conclusion, DT-13 is of low toxicity at the tested doses.  相似文献   

14.
AB-LIFE® is a probiotic product consisting of equal parts of three strains of Lactobacillus plantarum (CECT 7527, 7528, and 7529) blended with inert excipients. Whole genome sequencing was performed on each of the three strains. Antibiotic resistance was evaluated by genomic mining for resistance genes, and assessment for transferability. No risk of transfer potential was identified for any antibiotic resistance genes in the three strains. AB-LIFE® was evaluated for potential subchronic oral toxicity in rats, with dosages of 300 and 1000 mg/kg BW/day (equivalent to 5.55 × 1010 and 1.85 × 1011 CFU/kg BW/day). Survival of the three test strains through the gastrointestinal tract was supported by fecal analysis. No adverse effects were identified with respect to in-life parameters, clinical or anatomic pathology, translocation, or fecal chemical analyses. The no-observed-adverse-effect level (NOAEL) for AB-LIFE® in male and female rats was 1000 mg/kg BW/day (1.85 × 1011 CFU of AB-LIFE®/kg BW/day), the highest dose level evaluated. These results, in conjunction with a previous acute toxicity study in rats, support the conclusion that AB-LIFE® is safe for human consumption.  相似文献   

15.

Introduction

A combination of zidovudine (AZT), lamivudine (3TC) and lopinavir/ritonavir (LPV/r) is one of the most effective drugs for preventing mother-to-child transmission (PMTCT) of HIV. However, limited information is available regarding its systemic toxicity. This study aimed to investigate its potential toxicity.

Method

An acute oral toxicity test was conducted to assess the potential acute toxicity of AZT + 3TC + LPV/r. Bacterial reverse mutation, mammalian erythrocyte micronucleus and mouse spermatogonia chromosomal aberration tests were conducted to assess its potential genotoxicity. A 28-day feeding test was conducted to assess the potential subacute toxicity.

Results

In mice, the LD50 of the AZT + 3TC + LPV/r mixture was greater than 2000 mg/kg body weight (BW). The rate of micronucleated polychromatic erythrocytes (PCEs) increased in a dose-dependent manner in mice (P < 0.01). After treatment with AZT + 3TC + LPV/r for 28 days, the BW gain of male and female rats in the high-dose group was lower than that in the control group (P < 0.05); the relative weights of the liver, kidney, spleen and brain increased (P < 0.05); and pathological abnormalities appeared in the thyroid and spleen of male and female rats in the high-dose group. The haemoglobin (HGB) and red blood cells (RBCs) count in male and female rats decreased, but the white blood cells (WBCs) and lymphocyte apoptosis rates in male and female rats in the high-dose group increased (P < 0.05). The total protein, albumin, cholesterol and blood glucose levels of male and female rats in the high-dose group were significantly decreased (P < 0.05). The alanine aminotransferase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), creatinine (Cr) and blood urea nitrogen (BUN) levels of male and female rats in the medium- and high-dose groups increased significantly (P < 0.05).

Conclusion

The results suggest that AZT + 3TC + LPV/r may exhibit genotoxicity and subacute toxicity under experimental conditions.  相似文献   

16.
Thermolysin is a zinc metalloprotease that has potential uses in the food industry. The safety of thermolysin has not been demonstrated before, and therefore a series of standard toxicological tests to assess its potential toxicity was undertaken. The thermolysin used in this study was derived from the thermophilic bacterium Geobacillus stearothermophilus, which had undergone chemical mutagenesis to generate strains with increased thermolysin production. Acute toxicity studies in rats and mice showed that thermolysin powder is not acutely toxic with an oral LD50 of more than 18,000 mg/kg (2520 mg/kg thermolysin protein) in rats and more than 24,000 mg/kg (3360 mg/kg protein) in mice. Subchronic feeding studies in rats for 91 days at doses up to 1000 mg/kg (390 mg/kg protein) revealed no significant differences between treated and non-treated groups and a No Observed Effect Level (NOEL) of 1000 mg/kg (390 mg/kg protein) per day was established. Results from genotoxicity tests such as in vitro chromosomal aberration assay and in vivo mouse micronucleus were negative. Allergenicity sequence analysis revealed no evidence suggesting that thermolysin is an allergen. The data presented in this study support the conclusion that thermolysin is safe for use in food production.  相似文献   

17.
N-acetyl-l-threonine (NAT) is a dietary constituent that has been identified at low concentrations (<1 μg/g fresh weight) in numerous foods. The current paper reports the outcome of toxicology studies conducted to assess the effects of NAT. No evidence of mutagenicity or genotoxicity was observed in in vitro bacterial or in vivo mammalian studies. No mortalities or evidence of adverse effects were observed in Sprague–Dawley (SD) rats following acute oral administration of 2000 mg of NAT/kg of body weight (kg of bw). A 28-day repeated dose toxicity study was conducted in SD rats by incorporating NAT into diets at concentrations targeting up to 1000 mg of NAT/kg of bw/day. All rats survived until scheduled sacrifice and no biologically significant differences were observed in any of the NAT treatment groups for body weights, feed consumption, clinical signs, behavioral, ophthalmology, hematology, coagulation, clinical chemistry, organ weights, or gross or microscopic changes. Based on these results, NAT does not represent a risk for mutagenicity or genotoxicity, is not acutely toxic, and the no-observed-adverse-effect-level (NOAEL) for systemic toxicity from repeated dose dietary exposure to NAT is 848.5 and 913.6 mg/kg of bw/day for male and female SD rats, respectively.  相似文献   

18.
Artemisia capillaris (AC) has been used as an alternative therapy in obesity, atopic dermatitis, and liver diseases through several biological activity including anti-steatotic, antioxidant, and anti-inflammatory activities. Despite its ethnomedicinal benefits, no sufficient background information is available about the long-term safety and genotoxicity of the AC extract. Therefore, the present study was carried out to investigate the 13-week subchronic toxicity and genotoxicity of the AC extract according to the test guidelines published by the Organization for Economic Cooperation and Development. In the 13-week toxicity study using doses of 25, 74, 222, 667, and 2000 mg/kg body weight, oral administration of the AC extract in male and female rats did not result in any significant adverse effects in food/water consumption, body weight, mortality, hematology, serum biochemistry, organ weight and histopathology. Accordingly, the no-observed-adverse-effect level in rats of both genders was established for the AC extract at 2000 mg/kg/day, the highest dose level tested. In addition, the AC extract was not genotoxic in a battery of tests including Ames test, in vitro chromosome aberration assay and in vivo micronucleus assay. In conclusion, we demonstrated that the AC extract is considered as a safe traditional medicine for human consumption.  相似文献   

19.
DHA-rich algal oil ONC-T18, tested in a battery of in vitro and in vivo genotoxicity tests, did not show mutagenic or genotoxic potential. The acute oral LD50 in rats has been estimated to be greater than 5000 mg/kg of body weight. In a 90-day subchronic dietary study, administration of DHA-rich algal oil at concentrations of 0, 10,000, 25,000, and 50,000 ppm in the diet for 13 weeks did not produce any significant toxicologic manifestations. The algal oil test article was well tolerated as evidenced by the absence of major treatment-related changes in the general condition and appearance of the rats, neurobehavioral endpoints, growth, feed and water intake, ophthalmoscopic examinations, routine hematology and clinical chemistry parameters, urinalysis, or necropsy findings. The no observed adverse effect level (NOAEL) was the highest level fed of 50,000 ppm which is equivalent to 3,305 and 3,679 mg/kg bw/day, for male and female rats, respectively. The studies were conducted as part of an investigation to examine the safety of DHA-rich algal oil. The results confirm that it possesses a toxicity profile similar to other currently marketed algal oils and support the safety of DHA-rich algal oil for its proposed use in food.  相似文献   

20.
Antrodia cinnamomea (Ac) is a medicinal mushroom widely used for the treatment of abdominal pain, hypertension and hepatocellular carcinoma, but subchronic toxicity of this material has not yet been investigated. This present study was conducted to assess the 90-day oral toxicity of A. cinnamomea from submerged culture in male and female Sprague-Dawley (SD) rats. Eighty rats were divided into four groups, each consisting of ten male and ten female rats. Test articles were administered by oral gavage to rats at 3000, 2200 and 1500 mg/kg BW/day for 90 consecutive days and reverse osmosis water was used as control. All animals survived to the end of the study. During the experiment period, no abnormal changes were observed in clinical signs, body weight and ophthalmological examinations. No significant differences were found in urinalysis, hematology and serum biochemistry parameters between the treatment and control groups. Necropsy and histopathological examination indicated no treatment-related changes. According to the above results, the no-observed-adverse-effect level (NOAEL) of Antrodia cinnamomea is identified to be greater than 3000 mg/kg BW/day in Sprague-Dawley rats.  相似文献   

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