Trim artichokes Italian style: Halve 1 lemon and into a bowl of cold water squeeze juice from 1 half, dropping squeezed half into water. Do not cut off stems of artichokes. Working with 1 artichoke at a time, bend back outer leaves until they snap off close to base and discard several more layers of leaves in same manner until exposed leaves are pale green at top and pale yellow at base.
With a sharp stainless-steel knife cut off tops of leaves about 1 to 1 1/4 inches from top of artichoke. Trim fibrous parts from base of artichoke, being careful not to break off stem. Cut a thin slice from end of stem to expose a fresh cross section. Trim outer green fibrous part from stem, leaving pale core intact. Rub artichoke all over with cut side of remaining lemon half and put artichoke in bowl of lemon water. Repeat with remaining artichokes.
Fill a 4-quart saucepan three-fourths full with water and bring to a boil with the remaining 1/2 lemon. Quarter 1 artichoke lengthwise through stem and with a stainless-steel paring knife cut out the choke. Trim any spiky purple-tipped leaves. Halve quarters lengthwise and return to bowl. Prepare remaining artichokes in the same manner. Simmer artichokes in boiling water 5 minutes, or until almost tender, and drain in a colander. Artichokes may be prepared up to this point 1 day ahead, cooled completely, and chilled, rolled in damp paper towels in a sealable plastic bag.
Chop pancetta and mince garlic. Fill a 6-quart kettle three fourths full with water and bring to a boil with salt for fettuccine.
In a 12-inch deep heavy skillet cook pancetta in oil over moderate heat, stirring occasionally, until crisp and with a slotted spoon transfer to a bowl. Discard fat from skillet.
In skillet, heat butter over moderate heat until foam subsides and cook artichokes, stirring occasionally, until golden, about 5 minutes. Add garlic and cook, stirring, 1 minute. Add wine and simmer, stirring and scraping up browned bits, 1 minute.
Cook fettuccine in boiling water until al dente. Drain pasta. Add heated chicken broth to artichoke mixture and bring to a boil. Add pasta, pancetta, Parmesan, parsley and lemon juice, tossing to combine well.