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951.
Increasing pericardial effusion in cardiac transplant recipients   总被引:2,自引:0,他引:2  
Although pericardial effusion after cardiac surgery is frequent and usually benign, its etiology and prognosis after cardiac transplantation are unknown. During 1 year (1985-1986), 12 of our current transplant population (total, 189) developed moderate or large pericardial effusions confirmed by two-dimensional echocardiography. These effusions occurred within 1 month of transplantation in 10 patients and at 3 months and 4.5 years in the other two. Pericardiocentesis was performed because of clinical evidence of increasing effusions in eight patients, with demonstrable hemodynamic compromise secondary to tamponade in five. Pericardial fluid was sterile in all but one. Endomyocardial biopsy at the time of increasing effusion revealed moderate acute rejection in five patients, mild rejection in three, and no rejection in four. All three patients with mild rejection had moderate acute rejection on subsequent biopsy performed within 7 days. In two of the four with no rejection, repeat biopsy within 5 days showed moderate acute rejection; in a third, moderate rejection was present on biopsy performed 14 days later. Legionella dumoffii was isolated from the pericardial fluid of the fourth patient, whose subsequent biopsies never showed rejection. Three of the 12 patients developed progressive ventricular dysfunction sufficiently severe to require retransplantation. One patient died suddenly 12 months after transplantation, and autopsy examination revealed severe coronary artery disease. Two died of sepsis within 3 months of transplantation. Intense inflammatory infiltrates and thickening of the pericardium and epicardium were characteristically present in explanted and autopsy hearts.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
952.
BACKGROUND: Obesity is an important risk factor for hypertension, but epidemiologic studies provide evidence for the development of hypertension independent of obesity. In addition, the search for hypertension susceptibility genes should prove more informative when applied to a homogeneous subset of patients, such as those that are not obese. For this reason, we sought to identify genomic regions influencing susceptibility to hypertension in a nonobese sample of hypertensive African American families. METHODS: A genome-wide linkage scan was performed in a sample of 275 African American hypertensive families containing two or more nonobese (body mass index, < or = 30 kg/m2) individuals recruited by Networks of the Family Blood Pressure Program (FBPP). RESULTS: The best evidence for linkage of hypertension among the FBPP African American families was found on chromosome 2 (log of the odds [LOD]= 3.59 at 230 cM). All other chromosomes contained LOD scores less than 2. The African American sibships from the GENOA Network appear to largely contribute to the evidence for linkage on chromosome 2 (LOD = 4.07 at 233 cM). CONCLUSIONS: Significant evidence for linkage to hypertension in nonobese African American families was identified on chromosome 2q. These results suggest the presence of genes influencing susceptibility to adiposity-independent hypertension.  相似文献   
953.
One hundred and five patients with unstable angina and 175 with chronic stable angina were treated by primary percutaneous transluminal coronary angioplasty. Patients with unstable angina had had symptoms for a shorter time and were more likely to have angiographically complex lesions and lesions less than 10 mm in length than patients with chronic stable angina. Other baseline variables were not significantly different in the two groups. The overall primary success rate was similar in both groups (87% v 86%). Nine of the 14 unsuccessful procedures in those with unstable angina and nine of the 24 unsuccessful procedures in those with stable angina were the result of acute occlusion. These results led to a 9% frequency of procedure related myocardial infarction in patients with unstable angina and a 5% rate in those with stable angina (NS). The procedure related infarct rate tended to be higher in patients with unstable angina who had coronary angioplasty soon after an episode of unstable angina (mean 10 days) than in those in whom it was delayed (mean 35 days) (12% v 3%) (NS). In patients with unstable angina who had had a previous myocardial infarction procedure related infarction was significantly more common (18%) than in patients with no previous myocardial infarction (3%). The difference between those with and without previous infarction was also significant in patients with stable angina (10% v 3%).  相似文献   
954.
Patients with congenital central hypoventilation syndrome (CCHS) lack hypercapnic and hypoxic stimulation of ventilation but have demonstrated carotid body function in response to hyperoxia and to pharmacological stimulation with doxapram. This study investigated the ventilatory effects of almitrine bismesylate, a carotid body stimulant, in 12 patients with CCHS. Measurements of minute ventilation, tidal volume (VT), respiratory rate (RR) and transcutaneous PO2 (TCPO2) were taken before and after administration of 4.5 mg/kg and 6 mg/kg of almitrine. Twenty-four hour pharmacokinetic studies were performed in 7 patients who received 4.5 mg/kg and in 6 patients who received 6 mg/kg almitrine. There was no significant improvement in ventilatory and gas exchange parameters at either dose of almitrine despite appropriate peak serum concentration of the drug at the time of the studies. These results suggest that almitrine is not a useful ventilatory stimulant in children with CCHS.  相似文献   
955.
956.

Purpose:

To study the impact of adjuvant trastuzumab among patients achieving a pathologic complete response (pCR) after trastuzumab-based neoadjuvant systemic therapy (NST).

Patients and methods:

Patients with primary HER2-positive breast cancer treated with trastuzumab-based NST were categorised according to adjuvant trastuzumab administration and pCR status. Adjuvant trastuzumab became standard of care in 2006, this was the main reason patients in our cohort did not receive adjuvant trastuzumab. Kaplan–Meier was used to estimate survival. A test for interaction between adjuvant trastuzumab and pCR was completed.

Findings:

Of 589 patients, 203 (34.5%) achieved a pCR. After surgery, 109 (18.5%) patients in the entire cohort did not receive adjuvant trastuzumab. Among patients achieving a pCR, 31.3% received adjuvant trastuzumab compared with 68.8% among those who did not achieve a pCR (P=0.0006). Among patients achieving pCR, adjuvant trastuzumab did not further improve overall survival (OS) or relapse-free survival (RFS) (P=0.35 and P=0.93, respectively). Any benefit of adjuvant trastuzumab in OS and RFS among patients without a pCR did not achieve statistical significance (P=0.3 and P=0.44, respectively).

Conclusions:

In this cohort, patients treated with trastuzumab-based NST who achieved a pCR have excellent outcome regardless of whether they received adjuvant trastuzumab.  相似文献   
957.
Melanoma is the most deadly form of cutaneous malignancy, and its incidence rates are rising worldwide. In melanoma, constitutive activation of the BRAF/MEK/ERK (MAPK) and PI3K/AKT/mTOR (PI3K) signaling pathways plays a pivotal role in cell proliferation, survival and tumorigenesis. A combination of compounds that lead to an optimal blockade of these critical signaling pathways may provide an effective strategy for prevention and treatment of melanoma. The phytochemical fisetin is known to possess anti-proliferative and pro-apoptotic activities. We found that fisetin treatment inhibited PI3K signaling pathway in melanoma cells. Therefore, we investigated the effect of fisetin and sorafenib (an RAF inhibitor) alone and in combination on cell proliferation, apoptosis and tumor growth. Combination treatment (fisetin + sorafenib) more effectively reduced the growth of BRAF-mutated human melanoma cells at lower doses when compared to individual agents. In addition, combination treatment resulted in enhanced (i) apoptosis, (ii) cleavage of caspase-3 and PARP, (iii) expression of Bax and Bak, (iv) inhibition of Bcl2 and Mcl-1, and (v) inhibition of expression of PI3K, phosphorylation of MEK1/2, ERK1/2, AKT and mTOR. In athymic nude mice subcutaneously implanted with melanoma cells (A375 and SK-MEL-28), we found that combination therapy resulted in greater reduction of tumor growth when compared to individual agents. Furthermore, combination therapy was more effective than monotherapy in: (i) inhibition of proliferation and angiogenesis, (ii) induction of apoptosis, and (iii) inhibition of the MAPK and PI3K pathways in xenograft tumors. These data suggest that simultaneous inhibition of both these signaling pathways using combination of fisetin and sorafenib may serve as a therapeutic option for the management of melanoma.  相似文献   
958.
In the United States, high‐risk human papillomavirus (HPV) testing is recommended for women with atypical squamous cells of unknown significance (ASC‐US) cytology, and co‐testing with cytology and HPV is a recommended option for screening women aged ≥30 years. No population‐based data are available to examine utilization of HPV testing in the United States. Using the New Mexico HPV Pap Registry data resource, we describe population trends (2007–2012) in utilization and positivity rates for HPV testing as a routine co‐testing screening procedure and for triage of ASC‐US and other cytologic outcomes. For women aged 30–65 years co‐testing increased from 5.2% in 2007 to 19.1% in 2012 (p < 0.001). Overall 82% of women with ASC‐US cytology who did not receive co‐testing also had an HPV test. HPV positivity was age and cytology result dependent but did not show time trends. For women with negative cytology, 64% received an additional screening test within 3 years if no co‐test was done or if it was positive, but this was reduced to 47% with a negative co‐test. Reflex HPV testing for ASC‐US cytology is well established and occurs in most women. Evidence for reflex testing is also observed following other abnormal cytology outcomes. Co‐testing in women aged 30–65 years has more than tripled from 2007 to 2012, but was still only used in 19.1% of women aged 30–65 years attending for screening in 2012. Women receiving co‐testing had longer repeat screening intervals, but rescreening within 3 years is still very common even with co‐testing.  相似文献   
959.
960.
The Cox-Maze procedure has been performed successfully since 1987. The original surgery was performed by using the "cut and sew" technique and is considered quite complex and technically demanding; therefore, it never gained popularity among cardiac surgeons and referring cardiologists. As surgical ablation technology improved, the Cox-Maze procedure can now be performed by using new ablation devices that deliver different energy sources (radiofrequency, cryothermia, and others). The use of ablation technology simplified the technical aspects of the procedure and has led to decreased time on cardiopulmonary bypass, easier placement of ablation lines, and the development of various minimally invasive approaches to include off-pump techniques. The Heart Rhythm Society recommends surgical ablation for symptomatic patients, patients who are unable to take anticoagulation therapy, who have failed other therapies to include percutaneous catheter ablation, or by personal request. Therefore, with guidelines in place as to patient selection and newer, easier-to-use technology, more surgeons are tackling surgical ablation of atrial fibrillation, offering another treatment option for patients with lone atrial fibrillation. This article will review the current state of surgery for the ablation of lone atrial fibrillation.  相似文献   
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