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EARNINGS: United Health slumps after guidance disappoints Wall Street

Yahoo Finance's Alexis Christoforous and Jared Blikre break down the latest market action after United Health Group reports second quarter net income that beat Wall Street expectations.

Here's the performance of select health care stocks as of 10:00 am ET:

JNJ Johnson & Johnson 3.67%

NKTR(0) Nektar Therapeutics 1.36%

ABT Abbott Laboratories 1.07%

HCA HCA Hldg Inc 0.88%

LLY Lilly (Eli) 0.79%

ALXN Alexion Pharmaceuticals 0.80%

CELG Celgene Corp 0.72%

COO Cooper Cos 0.54%

BIIB Biogen Inc 0.54%

PFE Pfizer Inc 0.49%

BSX Boston Scientific Corporation 0.54%

MDT Medtronic plc 0.42%

SYK Stryker Corp 0.51%

PRGO(HB) Perrigo Co plc 0.35%

IBB iShs Nasdaq BioTech ETF 0.37%

BMY Bristol-Myers SQUIBB 0.35%

EVHC Envision Healthcare Corp 0.34%

VAR Varian Medical Systems Inc 0.28%

UHS Univl Health Svs'B' 0.24%

MRK Merck & Co 0.16%

ZTS Zoetis Inc 0.22%

BAX Baxter Intl Inc 0.18%

INCY Incyte Corp 0.10%

BDX Becton, Dickinson 0.15%

REGN Regeneron Pharmaceuticals 0.08%

IDXX Idexx Laboratories 0.16%

VRTX Vertex Pharmaceuticals 0.11%

ABMD Abiomed, Inc 0.03%

SHPG Shire plc ADS 0.12%

BMRN Biomarin Pharmaceutical 0.10%

XRAY Dentsply Sirona Inc 0.09%

GILD Gilead Sciences 0.03%

XLV S&P Sel Health Care Spdr Fd 0.02%

ISRG Intuitive Surgical -0.03%

ABC AmeriSourceBergen Corp -0.10%

IQV IQVIA Hldgs Inc 0.01%

ZBH Zimmer Biomet Hldgs Inc -0.04%

HOLX Hologic Inc 0.00%

DGX Quest Diagnostics -0.14%

ALGN Align Tech 0.11%

AGN Allergan plc -0.31%

TMO Thermo Fisher Scientific Inc -0.17%

HSIC Henry Schein Inc -0.24%

EW Edwards Lifesciences Corp -0.19%

RMD Resmed Inc -0.21%

AET Aetna Inc -0.40%

MCK McKesson Corp -0.54%

ABBV AbbVie Inc -0.34%

DVA DaVita Inc -0.48%

MYL Mylan NV -0.49%

CAH Cardinal Health Inc -0.71%

AMGN Amgen Inc -0.68%

LH Laboratory Corp Amer Hldgs -0.68%

CNC Centene Corp -1.75%