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1.

Background

Alkaloids of Sophora alopecuroides have good biological activity, and are widely used in clinical settings, which not only have pharmacological activities of anti-cancer, cancer suppression, as well as the inhibition, and killing of various microorganisms; but also possess extensive pharmacological effects on immune system, nervous system and cardiovascular system. The objective of this paper was to extract and isolate total alkaloids of Sophora alopecuroides (TASA), and to study their anti-tumor effects in H22 tumor-bearing mice.

Materials and Methods

TASA were extracted and isolated using thin-layer chromatography, and column chromatography; and the isolated compounds were analyzed using nuclear magnetic resonance. The inhibitory effects of TASA on tumor in H22-bearing mice were determined by MTT assay.

Results

Three compounds were isolated from Sophora alopecuroides L., which were matrine, oxymatrine and sophoridine, respectively. Meanwhile, mouse H22 sarcoma model was established and different doses of TASA apparently inhibited solid H22-tumor in mice; it inhibited the thymus, and spleen to some extent; the degree of inhibition was more obvious for the spleen.

Conclusion

TASA has an anti-tumor effect in H22 tumor-bearing mice.  相似文献   

2.

Background

Venenum bufonis is the dried white secretion of the auricular and skin glands of Bufo gargarizans Cantor, or Bufo melanostictus Schneider, Bufonidae. It is used in the treatment of deep-rooted carbuncle, boils and swelling; pain in the throat, heart stroke, coma, abdominal pain, vomiting and diarrhea. The objective of this paper is to preliminarily observe the effects of ethanol extract of Venenum bufonis on growth, and proliferation of human osteosarcoma U2OS cell lines, and to provide a theoretical basis for an in-depth study of the clinical application of Venenum bufonis for osteosarcoma inhibition, with its mechanism of action.

Materials and Methods

SRB assay was used to determine the effect of Venenum bufonis ethanol extract on U2OS cell line activity, and to detect its inhibitory dose-effect on osteosarcoma cells. FCM was applied to determine the effect of Venenum bufonis ethanol extract on U2OS cell apoptosis and to perform cell cycle analysis.

Results

As results, different Venenum bufonis ethanol extracts showed apparent concentration-effect relationships on U2OS cell lines. FCM analysis showed that it had a U2OS apoptosis promoting effect, which increased with increasing concentration. Cell cycle analysis revealed that the Venenum bufonis ethanol extract mainly arrested U2OS in the G0/G1 phase, preventing the cells from progressing to the S phase.

Conclusion

The study concluded that Venenum bufonis ethanol extract has an inhibitory effect on proliferation of osteosarcoma U2OS cells.  相似文献   

3.

Background

Sophora flavescens Ait. is a traditional Chinese medicine with a long history in China. It is mainly used in the treatment of heat dysentery and similar ailments in the clinical. The objective of this paper was to isolate, purify and identify alkaloids from Sophora flavescens Ait. and to explore their inhibitory effects on C6 glioma cells.

Materials and Methods

Column chromatography, extraction and NMR spectroscopy were used to structurally identify the isolated compounds. MTT assay and flow cytometry were used to detect the inhibitory effect of matrine on C6 cells.

Results

Three compounds were isolated from Sophora flavescens Ait., namely matrine, oxymatrine and lupeol. Different concentrations of matrine solution all had inhibitory effects on growth of C6 cell lines, which showed apparent dose-effect relationship. Compared with the control group, proportion of G0/G1 phase cells increased in each matrine concentration group to a maximum of 79.8%; proportion of S phase cells reduced, and proportion of G2/M phase cells declined slightly to a minimum of 6.3%, suggesting that after the action of matrine proliferation of C6 cells was significantly inhibited and the cells were arrested in the G1 phase.

Conclusion

We concluded that Sophora flavescens Ait. has an inhibitory effect on C6 cell proliferation.  相似文献   

4.

Background

Modern studies have shown that psoralen has a significant inhibitory effect on tumor growth in a variety of animals and humans.

Objective

To obtain coumarin compounds — psoralen and isopsoralen — from traditional Chinese medicine Psoralea corylifolia L. using chromatographic techniques and isolation and purification methods, and to observe the transplanted tumor growth inhibitory effects and adverse reactions of psoralen and isopsoralen in nude rats with osteosarcoma.

Methods

Dried ripe fruits of Psoralea corylifolia L. were taken as the raw material to prepare crude extract of Psoralea corylifolia L. by ethanol reflux method. Column chromatography was used to isolate the crude extract; compounds were structurally identified based on 1H-NMR, 13C-NMR spectra, the two compounds were identified as psoralen andisopsoralen, and their contents were 99.7% and 99.6, respectively. Nude rat model of osteosarcoma was established; the rats were randomized into: normal saline group, psoralen low- and high-dose groups, isopsoralen low- and high-dose groups, and cisplatin group. Osteosarcoma volume and weight inhibition rates in nude rats in each group were observed; radioimmunoassay was used to determine the serum alkaline phosphatase activity; peripheral blood cell and bone marrow nucleated cell counts were determined; light microscopy was used to observe heart, liver, spleen, lung, kidney, and tumor histopathology; and electron microscopy was used to observe the fine structure of tumor cells.

Results

Tumor volume inhibition rates were 43.75% and 40.18%, respectively, in the psoralen and isopsoralen low-dose groups, and tumor weight inhibition rates were 38.83% and 37.77%. Tumor volume inhibition rates were 67.86% and 66.96%, respectively, in the psoralen and isopsoralen high-dose groups, and tumor weight inhibition rates were 49.47% and 47.87%. Psoralen and ispsoralen markedly lowered serum AKP level. Psoralen and isopsoralen induced apoptosis or necrosis of osteosarcoma. After administration of high doses of psoralen and isopsoralen, toxic reactions such as writhing, lassitude, and hypoactivity were seen. Kidney histopathology showed tubulointerstitial dilatation and congestion, and inflammatory cell aggregation in the renal intercellular space. Psoralen and isopsoralen did not cause any significant toxic side effects to the bone marrow, or other organs such as heart, lung, liver, and spleen.

Conclusion

Psoralen and isopsoralen have growth inhibitory effects on transplanted tumor in nude rats with osteosarcoma, and can induce tumor cell apoptosis or necrosis, without significant toxic effects.  相似文献   

5.

Background

Nowadays there is a need to find naturally occurring substances from plants with antimicrobial activity as an alternative to available used antibiotics.

Materials and Methods

Salvadora persica (miswak) and Commiphora gileadensis were collected, dried and extracted with either methanol or warm water and the obtained extracts were assessed for their antibacterial activity against 5 different genera of bacteria using agar well diffusion method. The tested bacteria included some human pathogens.

Results

The obtained extracts exhibited considerable inhibitory effects against all the tested bacteria with various degrees of growth inhibition. It was shown that methanol extract was more effective compared to water extracts. The minimum inhibitory concentrations (MIC) of the methanol extracts ranged from 50–100 °g/ml. No toxicity was found using Artimia salina as test organism and no antitumor activity against Ehrlich ascites carcinoma.

Conclusion

S. persica and C. gileadensis showed moderate to high inhibitory activity on pathogenic bacteria with no toxicity and can be used traditionally as alternative medicine  相似文献   

6.

Background

The preference for a fairer skin-tone has become a common trend among both men and women around the world. In this study, seaweeds Sargassum polycystum and Padina tenuis were investigated for their in vitro and in vivo potentials in working as skin whitening agents. Seaweed has been used as a revolutionary skin repairing agent in both traditional and modern preparations. The high antioxidant content is one of the prime reasons for its potent action. It has been employed in traditional Chinese and Japanese medicine. For centuries, most medical practitioners in the Asian cultures have known seaweed as an organic source of vitamins, minerals, fatty acids like omega-3 and omega-6 and antioxidants. The present objective of the study was to evaluate the potent dermal protective effect of the two seaweeds Sargassum polycystum and Padina tenuis on human cell lines and guinea pigs.

Material and Methods

Seaweeds were extracted with ethanol and further fractionated with hexane, ethyl acetate and water. The extracts were tested for mushroom tyrosinase inhibitory activity, cytotoxicity in human epidermal melanocyte (HEM), and Chang cells. Extracts with potent melanocytotoxicity were formulated into cosmetic cream and tested on guinea pigs in dermal irritation tests and de-pigmentation assessments.

Results

Both Sargassum polycystum and Padina tenuis seaweeds showed significant inhibitory effect on mushroom tyrosinase in the concentration tested. SPEt showed most potent cytotoxicity on HEM (IC50 of 36µg/ml), followed by SPHF (65µg/ml), and PTHF (78.5µg/ml). SPHF and SPEt reduced melanin content in skin of guinea pigs when assessed histologically.

Conclusion

SPEt, SPHF and PTHF were able to inhibit HEM proliferation in vitro, with SPHF being most potent and did not cause any dermal irritation in guinea pigs. The results obtained indicate that SPHF is a promising pharmacological or cosmetic agent.  相似文献   

7.

Background

Multi-resistantmicroorganisms such as Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Candida tropicalis e Candida krusei are the main causes of microbial infections. Padina sanctae-crucis is a seaweed often used to check the contamination of ecosystems by materials such as heavy metals, but studies of the antimicrobial activity of the same seaweed were not found.

Methods

The tests for the minimum inhibitory concentration and modulation of microbial resistance, with the use of ethanolic and methanolic extracts of Padina Sanctae-cruces combined with drugs of the class of aminoglycosides and antifungal were used to evaluate the activity against the cited microorganisms.

Results

Was observed a modulation of antibiotic activity between the natural products and the E. coli and S. aureus strains, indicating a synergism and antagonism respectively.

Conclusions

The results showed a moderate modulatory effect against some microorganisms studied.  相似文献   

8.

Background

Bergenia purpurascens has tonic, haemostatic and anti-tussive actions. Anti-inflammatory and anti-bacterial activities of Bergenia purpurascens have not been reported so far. The objective of this paper is to provide experimental basis for the clinical application of Bergenia purpurascens through the pharmacodynamic study on its anti-inflammatory and anti-bacterial effects.

Methods

Experimental models of xylene-induced ear edema in mice, cotton pellet granuloma in rats, and acetic acid-induced peritoneal capillary permeability in mice were used to investigate the anti-inflammatory effect of Bergenia purpurascens; bacteriostatic and bactericidal effects of Bergenia purpurascens extract on Staphylococcus aureus (SA), methicillin-resistant Staphylococcus aureus (MRSA), and β-lactamase positive Staphylococcus aureus (ESBLs-SA), were observed in vitro.

Results

The results show that Bergenia purpurascens extract could markedly inhibit xylene-induced mouse ear edema, cotton pellet granulation tissue hyperplasia, and increased capillary permeability. Bergenia purpurascens extract has an inhibitory effect on SA, MRSA and ESBLs-SA.

Conclusion

We conclude that Bergenia purpurascens extract has certain anti-inflammatory and anti-bacterial effects.  相似文献   

9.

Background

This work aims at describing the traditional uses, to determine the antimicrobial potential of two different extracts hexane, acetone of the leaves of Citrus unshiu, Citrus sinensis, Citrus limon, Laurus nobilis, Citrus paradisi on clinical strain of H. pylori in a bid to identify potential sources of cheap starting materials for the synthesis of new drugs. H. pylori strain was a culture collection of Hacettepe University, Turkey.

Methods

The activity was quantitatively assessed on the basis of the inhibition zone, and their activity index was also calculated along with the MIC method.

Results

All the plants demonstrated antimicrobial activity against H. pylori with zone of inhibition diameters ranging from 0 – 30 mm and minimum inhibitory concentration (MIC) values ranging from 1:512–1:4096 dilutions.

Conclusion

The results may serve as scientific validation of the ethnomedicinal uses of the Citrus unshiu, Citrus sinensis, Citrus limon, Laurus nobilis, and Citrus paradisi in the treatment of H. pylori-related infections. However, further investigations would be necessary to determine their toxicological properties, in-vivo potencies and mechanism of action against H. pylori.  相似文献   

10.

Background

Through research it is found that the barks, stems, fruits and flowers of Eucommia ulmoides contain various compositions, such as lignin, cycloalkane and phenylpropanoids. The modern pharmacological research shows that Eucommia ulmoides has many functions, such as anti-aging, antitumor and bone cell proliferation. This paper studied the resin purification process optimization conditions and antihypertensive effect of Eucommia ulmoides Oliver.

Materials and Methods

The orthogonal experiment method was adopted to determine the purification effect of various macro-porous resins for eucommia ulmoides Oliver, and the SHR model was used to determine antihypertensive level of eucommia ulmoides Oliver.

Results

The optimal process of resin extraction and purification of Eucommia ulmoides Oliver was verified through the loading liquid concentration at 6 mg/ml, 20% ethanol used as the eluent; the flow rate control was 3.0, column volume per hour and the diameter-height ratio of adsorption column was 1:6; the extracts of Eucommia ulmoides Oliver can reduce SHR blood pressure, its antihypertensive effect is relatively stable and has no significant impact on HR, but the antihypertensive effect is lower than that of control medicine captopril. Also, the extracts of eucommia ulmoides Oliver can significantly increase the content of serum NO and reduce the content of ET.

Conclusion

The Eucommia ulmoides Oliver can relax blood vessels, reduce the peripheral resistance, reduce the returned blood volume, and eventually achieve the antihypertensive effect.  相似文献   

11.

Background

Flowers of Bauhinia kockiana were investigated for their anticancer properties.

Methods

Gallic acid (1), and methyl gallate (2), were isolated via bioassay-directed isolation, and they exhibited anticancer properties towards several cancer cell lines, examined using MTT cell viability assay. Pyrogallol (3) was examined against the same cancer cell lines to deduce the bioactive functional group of the phenolic compounds.

Results

The results showed that the phenolic compounds could exhibit moderate to weak cytotoxicity towards certain cell lines (GI50 30 – 86 µM), but were inactive towards DU145 prostate cancer cell (GI50 > 100 µM).

Conclusion

It was observed that pyrogallol moiety was one of the essential functional structures of the phenolic compounds in exhibiting anticancer activity. Also, the carboxyl group of compound 1 was also important in anticancer activity. Examination of the PC-3 cells treated with compound 1 using fluorescence microscopy showed that PC-3 cells were killed by apoptosis.  相似文献   

12.

Background

Helicobacter pylori is a gram-negative bacterium incriminated in gastroduodenal ulcers, and mucosa-associated lymphoid tissue lymphoma imposing a major burden on health care systems worldwide. Honeys have been shown to have in vitro activity against microaorganisms and suitable for use in ulcers, infected wounds and burns.

Objective

The study was aimed at evaluating the antimicrobial potential of honeys (Manuka−, Capillano®, Eco- and Mountain) at different concentrations (10%v/v, 20%v/v, 50%v/v and 75%v/v) against clinical isolates of H. pylori.

Methods

H. pylori was isolated from gastric biopsies of patients with gastroduodenal pathologies following standard microbiological procedures. Antimicrobial susceptibility of the isolates to different honey varieties was determined by the disk diffusion assay. Also, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the most potent honey was determined by the agar dilution method. Data were analysed using the Fisher exact test and statistical significance considered at p<0.05.

Results

All the four honey varieties exhibited antibacterial activity. The strongest inhibitory activity (82.22%) was demonstrated by Mountain honey at 75%v/v, followed by Capillano® and Manuka− honeys (75.56%), and Eco-honey (73.36%) at the same concentration. However, no statistically significant difference (p>0.05) was noted between the honeys at different concentrations. The MIC and MBC concentrations of Mountain honey were in the range 0.117 – 0.938ì/mL and 0.366 – 2.965ìg/mL respectively. The antimicrobial potential of these honeys at different concentrations were highly comparable to clarithromycin, the positive control.

Conclusion

These honeys may contain compounds with therapeutic potential against our local isolates of H. pylori.  相似文献   

13.

Background

The plant, Parquetina nigrescens is used in folklore medicine to treat diabetes mellitus and its complications in several parts of West Africa.

Objective

To determine the effect of Parquetina nigrescens extract on fasting blood glucose in alloxan-induced diabetic rats.

Methods

The blood glucose levels, complete blood count, erythrocyte indices and osmotic fragility, body and organ weights were evaluated.

Results

Diabetic rats treated with the extract showed significant (P<0.01) reduction of the blood glucose to levels comparable to that of the non-diabetic control and those treated with chlorpropamide (standard drug). Similarly, there was significant (P<0.01) reduction in the complete blood count in the diabetic rats.

Discussion

The anaemia, leucopenia and thrombocytopenia associated with the diabetes were corrected in the animals treated with the extract and chlorpropamide. The extract also reduced the erythrocyte osmotic fragility, body and organ weights. Parquetina nigrescens demonstrated antidiabetic property by reducing the elevated blood glucose in alloxan treated rats which is comparable to animals that received the standard drug.

Conclusion

Paraquetina nigrescens stabilized the erythrocyte membrane, decreased the body weight probably by lowering lipogenesis. However, the mechanism underlying the antidiabetic and haematinic properties of Parquetina nigrescens remains to be elucidated.  相似文献   

14.

Background

Zoonoses pose a risk to public health.

Objective

To carry out the investigation of the prevalence of gastrointestinal parasites of baboons, Papio anubis, frequenting the Wikki base Camp in Yankari National Park, Nigeria

Method

Formol-ether concentration technique was used to isolate parasite eggs and cysts from faecal samples.

Results

Parasites recovered were Ascaris lumbricoides, Ancylostoma duodenale, Strongyloides stercoralis, Fasciola sp, Schistosoma mansoni, Hymenolepis nana, and Trichostrongylus sp, and cysts of protozoan parasites Entomoeba histolytica, E. coli, and Iodamoeba butschii.

Conclusion

Most of the parasites identified are known to have high pathologic involvement in humans, implicating the baboons as potential source and reservoirs for human zoonotic parasitic infections although further molecular work would be necessary to ascertain if these gastrointestinal parasites are the same strains that infect humans  相似文献   

15.

Background

Antioxidants are of great importance for preventing oxidative stress that may cause several degenerative diseases. Studies have indicated phytochemicals have high free-radical scavenging activity, which helps to reduce the risk of chronic diseases. The aim of the present study is the determination of antioxidant properties, polyphenolic content and multidrug resistant bacteria of Salvia verticcilata L.

Materials and Methods

Methanol was used as the extraction solvent. The total phenolic content was calculated using Folin-Ciocalteau method and phenolic composition was determined by HPLC. The radical scavenging activity of plant was evaluated in vitro based on the reduction of the stable DPPH free radical. The reducing capacity was identified by using the FRAP method. The ability of Salvia verticcilata L. to increase the permeability of multidrug resistant bacterial cells was conducted by flow cytometric assay on Listeria innocua and E-coli.

Results

The amount of total phenolics was found to be 347.5 mg GA/g extract. The IC50 value and FRAP assay are 0.61, and 0.944 respectively, Free radical scavenging effect and FRAP values are less than synthetic antioxidant compounds (BHA and BHT). Eight phenolic compounds were found in Salvia verticcilata L. Intense concentration of S. verticcilata L. has destroyed 97 % of living cells for Listeria innocua and 94.86% for E-coli

Conclusion

This studyshows that methanolic extracts of Salvia verticcilata L. is a potential source of natural antioxidants and antimicrobial agent and can form the basis for pharmacological studies.  相似文献   

16.

Introduction

Alliumplants are an important part of the diet of many populations and there is a long-held belief in their health-enhancing properties such as cancer prevention. In this study, the anticancer and anti-inflammatory activities of the aqueous extract of the Allium ascalonicum bulbs have been studied.

Material and methods

The antiproliferative and anti-growth activity of the aqueous extract of A. ascalonicum was examined in vitro on different tumor cell lines. Furthermore, the acetic acid-induced vascular permeability as an in vivo assay was used for studying anti-inflammatory activity of the extract.

Results

The aqueous extract of A. ascalonicum had the most anti-growth activity on the cancer cell lines; Jurkat and K562 against Wehi 164 with lower cytotoxic preference. The extract also showed much less cytotoxicity against the normal cell (HUVEC) line and significant anti-inflammatory activity in vivo.

Conclusions

It is of interest that the extract of this plant has shown much less cytotoxicity against the normal cell line, and, if this also occurs in vivo, the use of this plant clinically for the treatment of cancer patients would have some scientific support. The results of these assays indicated that A. ascalonicum can be a candidate for prevention and treatment of many diseases related to inflammation and malignancy.  相似文献   

17.

Background

Vietnamese Sophora Root mainly contains active constituents such as alkaloids, and it has anti-tumour, antibacterial, and anti-inflammatory effects. The objective of the paper was to study the effects of Vietnamese Sophora Root on growth, adhesion, invasion and motility of mouse melanoma B16BL6 cells, and to preliminarily explore its mechanism of action.

Materials and Methods

MTT assay was used to detect the effect of Vietnamese Sophora Root aqueous extract on B16BL6 cell proliferation. Cell adhesion assay, reconstituted basement membrane invasion assay and chemotactic motility assay were used to observe the effects of Vietnamese Sophora Root aqueous extract on adhesion, invasion and motility of B16BL6 cells.

Results

Different concentrations of Vietnamese Sophora Root aqueous extracts had different degrees of inhibitory effects on B16BL6 proliferation. With the decrease of concentration, the proliferation inhibitory effect decreased and even turned to promoting effect. The extract significantly inhibited the adhesion of B16BL6 cells to the basement membrane component LN, and had a significant effect on both the invasive and migratory capacities of B16BL6 cells through the basement membrane.

Conclusion

We concluded that the aqueous extract of Vietnamese Sophora Root can inhibit the proliferation of melanoma cells, as well as their adhesion and movement.  相似文献   

18.

Context:

Community-acquired methicillin-resistant Staphylococcus aureus (MRSA) is becoming more prevalent in healthy athletic populations. Various preventive measures have been proposed, but few researchers have evaluated the protective effects of a prophylactic application of a commercially available product.

Objective:

To compare the persistent antimicrobial properties of a commercially available antimicrobial product containing 4% chlorhexidine gluconate (Hibiclens) with those of a mild, nonmedicated soap (Dr. Bronner''s Magic Soap).

Design:

Cross-sectional study.

Setting:

Microbiology laboratory, contract research organization.

Patients or Other Participants:

Twenty healthy human volunteers.

Intervention(s):

The test and control products were randomly assigned and applied to both forearms of each participant. Each forearm was washed for 2 minutes with the test or control product, rinsed, and dried. At, 1, 2, and 4 hours after application, each forearm was exposed to MRSA for approximately 30 minutes.

Main Outcome Measure(s):

Differences in numbers of MRSA recovered from each forearm, test and control, at each postapplication time point were compared.

Results:

Fewer MRSA (P < .0001) were recovered from the forearms treated with the test product (4% chlorhexidine gluconate) than from the forearms treated with the control product (nonmedicated soap).

Conclusions:

The 4% chlorhexidine gluconate product demonstrated persistent bactericidal activity versus MRSA for up to 4 hours after application.  相似文献   

19.

Background

Breast cancer is the most common cancer in women worldwide. About 5 to 10% of cases are due to an inherited predisposition in two major genes, BRCA1 and BRCA2, transmitted as an autosomal dominant form. Male breast cancer is rare and is mainly due to BRCA2 than BRCA1 germline mutations.

Objective

Molecular study of BRCA2 gene in man with familial breast cancer.

Methods

PCR and direct sequencing of BRCA2 gene.

Results

Identification of novel heterozygous germline mutation c.6428C>A ; p.Ser2143Stop of BRCA2 gene.  相似文献   

20.

Background

The genus Aloe has been the subject of several chemotaxonomic and phytochemical investigations. Aloe ferox is an important source of biologically active compounds like anthrones, chromones, pyrones, and flavonoids. It is a plant used extensively in traditional medicine. Despite the myriad of studies on the pharmacological profile of the plant, there still exists a dearth of scientific literature on the anatomical and morphological attributes of this important medicinal plant.

Materials and Methods

Hence, the objective of this study was to examine the foliar anatomy and micromorphological characteristics of A. ferox using light microscope and scanning electron microscope and to determine the elemental composition of the leaf sections by energy dispersive x-ray spectroscopy.

Results

Epidermal cells varied from round, square to hexagonal, with distinctive anticlinal walls and sunken stomata, equally distributed on both the adaxial and abaxial surfaces were observed. There were vertically elongated palisade cells with numerous chloroplasts in the palisade mesophyll layer. The EDXS analysis revealed Ca, K, S, Al, Mg, and Si as the major constituents of crystals present in the mesophyll.

Conclusion

Information on the foliar anatomy and micromorphology can further enlightened our perceptions on the inherent interrelationships between structure and function as regards the synthesis and secretion of bioactive secondary metabolites by plants.  相似文献   

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