instruction: this year how many patients were prescribed send 500mg vial during the same month after the partial ostectomy nec?
response: SELECT COUNT(DISTINCT t1.subject_id) FROM (SELECT admissions.subject_id, procedures_icd.charttime FROM procedures_icd JOIN admissions ON procedures_icd.hadm_id = admissions.hadm_id WHERE procedures_icd.icd9_code = (SELECT d_icd_procedures.icd9_code FROM d_icd_procedures WHERE d_icd_procedures.short_title = 'partial ostectomy nec') AND DATETIME(procedures_icd.charttime, 'start of year') = DATETIME(CURRENT_TIME(), 'start of year', '-0 year')) AS t1 JOIN (SELECT admissions.subject_id, prescriptions.startdate FROM prescriptions JOIN admissions ON prescriptions.hadm_id = admissions.hadm_id WHERE prescriptions.drug = 'send 500mg vial' AND DATETIME(prescriptions.startdate, 'start of year') = DATETIME(CURRENT_TIME(), 'start of year', '-0 year')) AS t2 ON t1.subject_id = t2.subject_id WHERE t1.charttime < t2.startdate AND DATETIME(t1.charttime, 'start of month') = DATETIME(t2.startdate, 'start of month')