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51.
The authors describe a cas of pacemaker malfunction due to a critical increase of impedance resulting from air entrapment in the pacemaker pocket.  相似文献   
52.
This study evaluated the systemic toxicity, arrhythmogenicity, and mode of death of convulsant and supraconvulsant doses of lidocaine, bupivacaine, and ropivacaine. Experiments in awake dogs were designed to mimic the clinical situation of an accidental intravenous (IV) injection of local anesthetics. On the first experimental day, lidocaine (8 mg.kg-1.min-1), bupivacaine (2 mg.kg-1.min-1), and ropivacaine (2 mg.kg-1.min-1) were infused intravenously until seizures occurred (n = 6 for each group). The average dose and arterial plasma concentration at seizure onset was 20.8 +/- 4.0 mg/kg and 47.2 +/- 5.4 micrograms/mL for lidocaine, 4.31 +/- 0.36 mg/kg and 18.0 +/- 2.7 micrograms/mL for bupivacaine, and 4.88 +/- 0.47 mg/kg and 11.4 +/- 0.9 micrograms/mL for ropivacaine. The margin of safety between the convulsive and lethal doses was determined by administering two times the convulsive dose 24 h later. Two dogs given lidocaine died because of progressive hypotension, respiratory arrest, and finally cardiovascular collapse with an average peak plasma concentration (Cmax) of 469 micrograms/mL. No ventricular arrhythmias were observed in this group. Ventricular arrhythmias occurred in five of six dogs receiving bupivacaine. Four animals died because of hypotension, respiratory arrest, and cardiovascular collapse. One additional animal died because of ventricular fibrillation. The Cmax for bupivacaine was 70.1 +/- 14.6 micrograms/mL in nonsurvivors. In the ropivacaine group one animal died because of hypotension, respiratory arrest, and cardiovascular collapse (Cmax = 72.4 micrograms/mL). A surviving dog had transient premature ventricular contractions. Twenty-four hours later three times the convulsive dose was administered to the survivors.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
53.
For 5 patients with univentricular heart associated with apico-caval juxtaposition, an extracardiac Fontan procedure was carried out using an artificial graft bridging the vertebra to avoid graft compression by the vertebra and the ventricle. For 2 patients representing nonconfluency between the inferior caval vein and the hepatic vein, a hand-made, shoe-tree graft was used. Postoperatively all patients are doing well without a stenotic venous pathway. This extracardiac operation using an artificial graft bridging the vertebra may be advantageous for univentricular heart associated with apico-caval juxtaposition to prevent a postoperative stenotic venous pathway.  相似文献   
54.
55.
A randomized double-blind study was conducted in 50 orthopedic patients to determine the effect of epinephrine and phenylephrine on the anesthetic properties of intrathecally administered tetracaine. Two doses of each vasoconstrictor agent were studied: 0.2 mg of epinephrine, 0.3 mg of epinephrine, 1 mg of phenylephrine, and 2 mg of phenylephrine. The results show that both vasoconstrictor agents in the doses used significantly prolong duration of sensory anesthesia and motor blockade produced by the subarachnoid administration of tetracaine. At equipotent doses no differences existed between the ability of epinephrine and phenylephrine to prolong the duration of spinal anesthesia produced by tetracaine.  相似文献   
56.

Background/aim

The combination of pegylated interferon (PEG-IFN) and ribavirin (RBV) is the current treatment for chronic hepatitis C (CHC). The treatment is thought to suppress viral replication and induce viral clearance via immunomodulatory effects. For this reason, concern exists for the use of this treatment in recipients of a solid organ transplantation. We sought to evaluate the safety and efficacy of PEG-IFN/RBV in heart transplant recipients with CHC.

Methods

From June 2005 to September 2009, we treated three CHC patients with heart transplantation. PEG-IFN alpha2b and RBV doses and treatment duration were set according to the hepatitis C virus (HCV) genotype and body weight as per current recommendations. Dose reductions were dictated by individual patient tolerability. Cardiac safety was monitored by clinical examinations, echocardiography, and measurement of troponin I and B-type natriuretic peptide, as well as endomyocardial biopsies.

Results

All three patients, displayed HCV genotype 1b infection, viral loads of >5 logs, and a Scheuer fibrosis score ≥ 2. Two of them completed the prescribed treatment course becoming sustained virological responders. The other patient had an initial complete virological response, but subsequently experienced a viral breakthrough after reduction of PEG-IFN and withdrawal of RBV due to severe anemia. We observed no cardiovascular adverse events nor rejection episodes. Posttreatment clinical history and examination, electrocardiography, and echocardiography did not show any sign of graft dysfunction.

Conclusions

Treatment with PEG-IFN/RBV may be safely offered to stable heart transplant recipients with CHC and signs of liver disease progression. Close monitoring of treatment safety is mandatory.  相似文献   
57.
The presence of clear cells in genital tract neoplasms often reflexly prompts the diagnosis of a clear cell tumor but clear cells may be seen in many other neoplasms. In one such, those of endometrioid type, they are well known and generally readily characterized when they have the secretory pattern that recapitulates the well-known morphology of early secretory endometrium. In this report, we describe various clear cell morphologies, some possibly related to the secretory variant, but others not, and all potentially the source of significant diagnostic difficulty. We reviewed 21 endometrioid tumors that occurred in patients from 27 to 88 (median 64) years. Most had an adnexal mass (13) or abdominal swelling (4), but 4 presented with vaginal bleeding. One tumor formed a cystic mass in the pelvis, 1 tumor involved the right fallopian tube, 1 the endometrium, and 18 the ovary. One tumor was a cystadenofibroma, 1 a borderline tumor, and 19 were adenocarcinomas. Twelve patients had stage I, 4 stage III, 1 stage IV, and 4 were unstaged. One patient who had a previous hysterectomy and salpingo-oophorectomy underwent resection of a cystic pelvic mass; others all were treated with abdominal hysterectomy and salpingo-oophorectomy. All the neoplasms had the typical architecture of endometrioid tumors but differed markedly in their cytoplasmic features. In 18 of the tumors at least one-third of the cells had clear cytoplasm and 3 had only clear cells. The clear cytoplasm varied from foamy to empty and the nuclei had a variable location, basilar, central, and apical. The clear cells were associated with squamous differentiation in only 1 case in which the change appeared hydropic. By immunohistocytochemistry, the clear cells were focally positive for epithelial markers in most cases but in some cases one or more of these immunostains were negative. Tubulocystic, solid, and papillary patterns of clear cell carcinoma were absent. Periodic acid-Schiff was focally positive for glycogen in the cytoplasm in 5 cases. Although a few cases had a focal slight resemblance to secretory endometrioid carcinoma most did not and the orderly morphology of classic secretory carcinoma was noteworthy for its absence. The nature of the cytoplasmic clarity is usually uncertain but is likely variably owing to lipid, mucin or glycogen accumulation, or is a hydropic change. The distinction from clear cell carcinoma depends on awareness of this unusual variant of endometrioid neoplasia and a lack of the distinctive patterns of clear cell carcinoma; at this time, special studies, including immunohistochemistry, do not aid significantly although certainly negative reactions, such as for thyroglobulin protein (arguing against clear cell struma ovarii) may play a role in some differential diagnostic considerations. There are prognostic and therapeutic implications in the distinction with clear cell carcinoma.  相似文献   
58.
59.
Panic disorder and phobic anxiety disorders are common disorders that are often chronic and disabling. Genetic epidemiologic studies have documented that these disorders are familial and moderately heritable. Linkage studies have implicated several chromosomal regions that may harbor susceptibility genes; however, candidate gene association studies have not established a role for any specific loci to date. Increasing evidence from family and genetic studies suggests that genes underlying these disorders overlap and transcend diagnostic boundaries. Heritable forms of anxious temperament, anxiety-related personality traits and neuroimaging assays of fear circuitry may represent intermediate phenotypes that predispose to panic and phobic disorders. The identification of specific susceptibility variants will likely require much larger sample sizes and the integration of insights from genetic analyses of animal models and intermediate phenotypes.  相似文献   
60.
The purpose of this review is to address some common problems involving the diagnosis of trophoblastic lesions.  相似文献   
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