1. A drill bit for directional boring, comprising:
a bit body having a frontwardly facing, circular main cutting surface having a number of main cutting teeth disposed thereon;
a gage cutter extending radially outwardly from the main cutting surface, which gage cutter mounts at least one frontwardly facing gage cutting tooth thereon suitable for cutting in a circle during straight boring and over an angle defined by less than a full rotation of the bit in order to steer the bit; and
a heel on an outer side surface of the bit body at a position opposite to the gage tooth, which heel provides a reaction surface for the gage cutter;
wherein the bit body and gage cutter have a nearly circular side profile along a front portion thereof such that a maximum radial clearance between the side profile and a side wall of a hole being drilled is not greater than about 10 percent of the radius of a circle cut by the gage tooth.
2. The drill bit of claim 1 wherein the gage cutter is substantially crescent-shaped in cross section, having a maximum width at the gage tooth.
3. The drill bit of claim 1 wherein the heel extends radially outwardly further than the main cutting surface at a location rearwardly offset from the main cutting surface.
4. The drill bit of claim 3 wherein the heel comprises a radially outwardly extending tooth.
5. The drill bit of claim 1 wherein the gage cutter is substantially crescent-shaped in cross section and has a plurality of gage cutting teeth that lie on an arc.
6. The drill bit of claim 5, wherein the gage cutter has a maximum width at the center of the arc defined by the gage teeth.
7. The drill bit of claim 1, wherein the maximum radial clearance between the side profile and a side wall of a hole being drilled is not greater than about 5 percent of the radius of the circle cut by the gage tooth.
8. The drill bit of claim 1, wherein the maximum radial clearance between the side profile and a side wall of a hole being drilled is in the range of about 2 to 7 percent of the radius of the circle cut by the gage tooth.
9. The drill bit of claim 1, wherein the main cutting surface lies in a plane perpendicular to a longitudinal axis of rotation of the bit, and has a number of carbide buttons set therein at varying distances from the longitudinal axis of rotation of the bit, and has drilling fluid outlet ports opening thereon.
10. The drill bit of claim 9, wherein the gage cutter comprises a crescent-shaped extension of the main cutting surface.
11. The drill bit of claim 10, wherein the gage cutter has a rearwardly sloped, frontward facing peripheral surface in which the gage cutting tooth is mounted.
12. The drill bit of claim 10, wherein the gage cutting tooth comprises a round-headed button that extends outwardly at an angle in the range of 30 to 60 degrees relative to the axis of rotation of the bit.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method of treating previously untreated mesothelioma in a human patient, comprising administering to the patient effective amounts of an anti-VEGF antibody, wherein said anti-VEGF antibody is bevacizumab, and an at least one anti-neoplastic composition, wherein said anti-neoplastic composition comprises at least one chemotherapeutic agent.
2. The method of claim 1, wherein the anti-VEGF antibody is administered concomitantly with the at least one chemotherapeutic agent.
3. The method of claim 1, wherein the mesothelioma is metastatic.
4. The method of claim 1, wherein the chemotherapeutic agent is selected from the group consisting of alkylating agents, antimetabolites, folic acid analogs, pyrimidine analogs, purine analogs and related inhibitors, vinca alkaloids, epipodopyyllotoxins, antibiotics, L-Asparaginase, topoisomerase inhibitor, interferons, platinum cooridnation complexes, anthracenedione substituted urea, methyl hydrazine derivatives, adrenocortical suppressant, adrenocorticosteroides, progestins, estrogens, antiestrogen, androgens, antiandrogen, and gonadotropin-releasing hormone analog.
5. The method of claim 1, wherein the anti-neoplastic composition comprises a combination of at least two chemotherapeutic agents.
6. The method of claim 1, wherein the anti-VEGF antibody is administered intravenously.
7. The method of claim 1, wherein the anti-VEGF antibody is administered to the patient at about 5 mgkg to about 15 mgkg every 2 to 3 weeks.
8. The method of claim 6, wherein the administration is by intravenous infusion over 30-90 minutes.
9. The method of claim 1, wherein said at least one chemotherapeutic agent is cisplatin or a folic acid analog.