要通过Alpha Vantage API获取纳斯达克报价，您可以使用以下代码示例：

import requests

api_key = 'YOUR_API_KEY'
symbol = 'NASDAQ:MSFT'

url = f'https://www.alphavantage.co/query?function=GLOBAL_QUOTE&symbol={symbol}&apikey={api_key}'

response = requests.get(url)
data = response.json()

if 'Global Quote' in data:
    quote = data['Global Quote']
    print(f"Symbol: {quote['01. symbol']}")
    print(f"Open: {quote['02. open']}")
    print(f"High: {quote['03. high']}")
    print(f"Low: {quote['04. low']}")
    print(f"Price: {quote['05. price']}")
    print(f"Volume: {quote['06. volume']}")
    print(f"Latest Trading Day: {quote['07. latest trading day']}")
    print(f"Previous Close: {quote['08. previous close']}")
    print(f"Change: {quote['09. change']}")
    print(f"Change Percent: {quote['10. change percent']}")
else:
    print("No data available for the symbol.")

请确保将YOUR_API_KEY替换为您自己的Alpha Vantage API密钥。此代码将向Alpha Vantage API发送请求，并从响应数据中提取和打印出纳斯达克报价信息。

如果您仍然无法获取纳斯达克报价，可能是因为Alpha Vantage API不支持该功能。在这种情况下，您可以尝试使用其他金融数据API，如Yahoo Finance API或Google Finance API。