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991.
This paper describes a patient with retroperitoneal malignant fibrous histiocytoma who underwent surgical removal of the tumor 6 times. It is difficult to remove locally recurrent retroperitoneal malignant fibrous histiocytoma many times by repeat surgery, since the tumor tends to adhere tightly to the surrounding scar tissue. In the 5th and 6th operations we conducted on the patient, a harmonic scalpel was useful for separating the tumor from the scar tissue at the previous surgical site.  相似文献   
992.
In order to study the effect of atrial tachycardia on the release of atrial natriuretic peptide (ANP), AVP, and methionine enkephalin (M-Enk), plasma concentrations of these peptides in the right ventricle were determined in patients with various arrhythmias (N = 10) during cardiac catheterization and incremental atrial pacing. Each pacing (100 per min, the maximum rate for 1:1 atrioventricular conduction, and 200 per min) lasted 4 to 5 min. Plasma ANP was significantly increased from 53.1 +/- 12.2 in the resting condition to 168.9 +/- 59.9 pmol/l at a pacing rate of 200 beats per min (P less than 0.05); plasma AVP tended to decrease, but not significantly, and plasma M-Enk did not change at all. Pulse pressure in the right atrium (PPRA) and mean right atrial pressure (MRAP) tended to increase during the pacing, and at the rate of 200 beats per min PPRA was significantly higher than at the rate of 100 beats per min. Mean arterial blood pressure, plasma osmolality, and plasma sodium and potassium concentrations did not change significantly. There were significant correlations between plasma ANP and PPRA, MRAP and heart rate. These results indicate that atrial pacing stimulates ANP release with a rise in right atrial pressure, but does not influence M-Enk and AVP releases.  相似文献   
993.
In order to investigate the physiological role of the brain renin-angiotensin system in the regulation of vasopressin (ADH) release, angiotensin II (Ang II, 10 ng/kg/min) or 1-Sar-8-Ile-Ang II (50 ng/kg/min), an Ang II antagonist, was administered intracerebroventricularly to dogs (n = 42) anesthetized with urethane and chloralose after morphine sedation. The effects of the intravenous infusion of either 0.15 M or 2.5 M NaCl (0.1 ml/kg/min, 75 min) were also studied. In control dogs, artificial cerebrospinal fluid (ACSF) was administered at a rate of 10 microliter/min for 105 min. ACSF given intracerebroventricularly plus 0.15 M NaCl given intravenously did not affect ADH release, but 2.5 M NaCl given intravenously raised the plasma ADH level in parallel with the rise in plasma osmolality. Heart rate and blood pressure did not change significantly in ACSF along with 0.15 M NaCl, but heart rate increased significantly in ACSF along with 2.5 M NaCl. Ang II along with 0.15 M NaCl significantly raised plasma ADH and decreased heart rate without any changes in blood pressure. Ang II along with 2.5 M NaCl brought about a significant rise in plasma ADH level, arterial blood pressure, heart rate, and plasma osmolality. But simultaneous application of Ang II and 2.5 M NaCl did not result in a larger rise in plasma ADH than that expected from the effects of the two stimulations given separately. Namely, Ang II did not potentiate ADH release elicited by osmotic stimulation. Ang II antagonist given intracerebroventricularly neither affected ADH release and the cardiovascular system in 0.15 M NaCl nor inhibited ADH release in response to osmotic stimulation.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
994.
995.

Background

Cardiovascular implantable electronic devices (CIEDs) are common in patients undergoing heart transplantation (HT), and complete removal is not always possible at the time of transplantation.

Methods

We retrospectively assessed the frequency of retained CIED leads and clinical consequences in consecutive HT patients from 2013 to 2016. Clinical outcomes included bacteremia, upper-extremity deep venous thrombosis (UEDVT), lead migration, and inability to perform magnetic resonance imaging (MRI).

Results

A total of 138 patients (55?±?11 years of age, 76% male) were identified; 37 (27%) had retained lead fragments (RLFs) at discharge. Patients with RLFs were older, had longer lead implantation time before HT, and a higher prevalence of dual-coil CIED leads compared with those without RLFs (P?<?.05 for all). Lead implantation time was identified as an independent predictor for RLFs (P?<?.05). Patients with RLFs had a higher frequency of DVT compared with the non-RLF group during the 1-year study period (42% vs 21%; P?<?.04). There was no difference in bacteremia. Fourteen patients (38%) could not undergo clinically indicated MRI.

Conclusion

RLFs after HT occur commonly and are associated with a higher rate of UEDVT and limit the use of MRI. Although no significant difference was found in the rates of bacteremia between the groups, this finding might be explained by the overall low incidence. Patients with risk factors for RLFs should be identified before transplantation, and complete lead removal should be considered with a multidisciplinary approach.  相似文献   
996.
A 25-year-old woman was admitted to our hospital with goiter. The diagnosis was Grave's disease. Diagnostic transthoracic echocardiography revealed a hyperdynamic stage of the heart with right ventricular dilation. Doppler echocardiography showed mild to moderate tricuspid regurgitation and elevated systolic right ventricular pressure. Right heart catheterization revealed high cardiac output (9.49 l/min) and pulmonary hypertension (57 mmHg) with increased pulmonary vascular resistance and total pulmonary resistance. No intracardiac shunts were detected. Since neither thiomazole nor propylthiouracil was effective and both caused side effects, she underwent subtotal thyroidectomy. After the surgery, pulmonary hypertension improved and cardiac output normalized, but without normalization of pulmonary vascular resistance and total pulmonary resistance. Reversible pulmonary hypertension may occur in patients with hyperthyroidism. Increased pulmonary blood flow and sustained high pulmonary artery resistance were suspected as the causes of pulmonary hypertension. In addition, pulmonary endothelial dysfunction as a result of sustained increased pulmonary blood flow could be another cause of pulmonary hypertension.  相似文献   
997.
998.

Background

Decoupling between diastolic pulmonary arterial pressure (dPAP) and pulmonary arterial wedge pressure (PAWP) is an index of pulmonary vasculature remodeling and provides prognostic information. Furthermore, decoupling may change during incremental left ventricular assist device (LVAD) speed changes.

Methods and Results

In this prospective study, patients underwent an echocardiographic and hemodynamic ramp test after LVAD implantation and were followed for 1 year. The change in decoupling (dPAP???PAWP) between the lowest and highest LVAD speeds during the ramp test was calculated. Survival and heart failure admission rates were assessed by means of Kaplan-Meier analysis. Eighty-seven patients were enrolled in the study: 54 had a Heartmate II LVAD (60.8 ± 9.3 years of age and 34 male) and 33 had an HVAD LVAD (58.6 ± 13.2 years of age and 20 male). Patients who experienced greater changes in decoupling (Δdecoupling >3 mm Hg) had a persistently elevated dPAP at incremental LVAD speed and had worse 1-year heart failure readmission–free survival compared with the group without significant changes in the degree of decoupling (41% vs 75%; P?=?.001).

Conclusions

An increase in decoupling between dPAP and PAWP at incremental LVAD speed changes was associated with worse prognosis in LVAD patients.  相似文献   
999.
Nine antigens systems were defined. Two were related to HLA-A,B,C and to Ia-like antigens; the others could be grouped into three categories. (i) NL-22, NL-1: NL-22 antibody reacted with leukemia cells from 12 to 16 cases of null cell acute lymphocytic leukemia (null-ALL) but not with any other type of leukemia tested or with lymphoid cells of various origins. Among cultured cell lines tested, one (NALM-6) of three null-ALL cell lines was positive, the others were negative. Absorption analysis confirmed the restriction of NL-22 antigen to null-ALL. NL-1 antibody was reactive with leukemia cells from 10 to 16 cases of null-ALL and 3 of 6 cases of chronic myelocytic leukemia in blastic crisis (CML-BC). The antigen was present also on a minor population of normal lymphoid cells. The distribution and molecular weight (100,000; glycoprotein) of the NL-1 antigen resembled that of the previously described common ALL antigen (cALL). (ii) NL-30, NL-4: Both antibodies exhibited almost identical patterns of reactivities against cultured cell lines tested. They reacted with leukemia cells from some cases of null-ALL, adult T-cell leukemia, and CML-BC, although they showed discordance in their reactivities against a panel of leukemia cells, (iii) NL-9, NL-8, NL-25: These three antibodies detect serologically distinguishable determinants on a broad range of leukemias and normal lymphoid and hematopoietic cell types. The antibodies analyzed in this study provide evidence for the heterogeneity of null-ALL by demonstrating a variety of antigen phenotypes on leukemia cells. One of the antigens (NL-22) appears to be restricted to null-ALL.  相似文献   
1000.
Conclusions: At the second postoperative year, there were no significant differences between results for vertigo and hearing after endolymphatic sac drainage with steroid instillation surgery (EDSS) and EDSS with posterior tympanotomy with steroids at the round window (EDRW). In particular, as regards hearing recovery to the preoperative level, the periods after EDRW were shorter than those after the second EDSS. Objectives: Patients sometimes faces recurrent problems years after EDSS due to endolymphatic sac closure and/or disease progression. In the present study, we examined the effects of EDRW on vertigo and hearing after revision surgery for intractable relapsed Meniere’s disease. Methods: Sixteen patients with Meniere’s disease had revision surgery due to intractable recurrence of disease, and were followed up regularly at least for 2 years. As revision surgery, EDSS was performed repeated in eight cases and EDRW was performed in the other eight. There were no significant differences between the patients’ backgrounds in the two groups. Results: Periods of hearing recovery to the preoperative level were 11.5 ± 4.4 months after the first EDSS, although it took 16.4 ± 2.6 months longer after revision surgery with the second EDSS (p = 0.038 < 0.05: first EDSS vs second EDSS) and was 10.0 ± 3.3 months shorter after revision surgery with EDRW (p = 0.010 < 0.05: second EDSS vs EDRW).  相似文献   
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