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The deliberate reduction of blood pressure in an attempt to reduce intraoperative blood loss has generated significant controversy in the 30 years since its clinical introduction. Numerous series have been reported, but few have met generally accepted, current criteria for controlled studies. In this article, the effect of blood pressure reduction on organ perfusion will be presented together with a review of techniques of achieving hypotension. A summary of results is included and, based on this data, recommendations are offered regarding the application and limits of deliberate hypotension.  相似文献   

3.
The effect of prostaglandins (PGs) on the hepatic biotransformation of hexobarbital (Hechi) and p-chloro-N-methylaniline (PCMA) was determined in male rats. PCMA metabolism in slices was decreased by all PGs (PGA1, PGB1, PGE1, PGE2, PGF1alpha, PGF2alpha), ranging in concentration from 1 mu M to 1 mM. PGA1, at 1 mM, produced the greatest degree of inhibition, 39%. PG addition to microsomes, however, failed to alter PCMA metabolism. In contrast to PCMA biotransformation, Hechi metabolism was increased by all PGs in slices but not in liver subfractions. PGs of the E and F series were the most potent, producing a two-fold increase in Hechi metabolism at 1 mM after a 20 min preincubation. The increased effect was observed as early as 10 min and lasted for 4 hr. The relationship of PG metabolism and binding to cytochrome P-450 is presented as a possible mechanism to account for the opposite effects on Hechi and PCMA, type I and II substrates respectively, metabolism.  相似文献   

4.
To investigate the development of airway hyperresponsiveness in infantile guinea pigs, animals (10 days old) were immunized twice and challenged by inhalation of 1% ovalbumin for 10 min with 7 days intervals. Similar to adult guinea pigs, infantile ones developed an increased airway responsiveness to acetylcholine 24 hr after antigen challenge. There was a marked increase in the number of total leukocytes, eosinophils and lymphocytes in bronchoalveolar lavage fluid (BALF). Suplatast tosilate (suplatast) and pemirolast potassium (pemirolast) given orally throughout the experiments suppressed the development of airway hyperresponsiveness in infantile animals. They showed similar potency in the suppression of eosinophil accumulation in BALF and lung tissue, while suplatast inhibited lymphocyte accumulation stronger than pemirolast. Collectively, the present model of airway hyperresponsiveness in infantile guinea pigs may be useful in predicting the efficacy of antiallergic agents in the treatment of asthmatic children.  相似文献   

5.
Intramuscular artemether given for five days was evaluated prospectively in 32 patients with acute recrudescent Plasmodium falciparum malaria. All patients had experienced one or more treatment failures with one or more courses of the following drugs: chloroquine, amodiaquine, sulphadoxine-pyrimethamine and erythromycin given alone or in combination. There was a prompt response to treatment with fever and parasite clearance times of 10.7 (3.6) h (range 6-24) and 32.3 (8.3) h (range 24-48) respectively. Parasite reduction at 24 h was 93.2 (7.8)% (range 75-100). The cure rate on day 14 was 100%. The drug was well tolerated. These results suggest that artemether is rapidly effective in acute recrudescent Plasmodium falciparum malaria and is without deleterious side effects.  相似文献   

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Mitral valve repair was performed in six patients by transferring the posterior tricuspid leaflet with its sub-valvular apparatus onto the mitral valve. This new technique considers the tricuspid valve as the patients own tissue bank where the posterior leaflet and eventually the adjacent part of the anterior leaflet is used as a "donor" valve, based on the knowledge that the right atrio-ventricular valve can be efficiently repaired with a very low risk of significant dysfunction. The mitral repair consists of incorporating the tricuspid autograft by securing the tricuspid papillary muscle to the mitral papillary muscle and by suturing the leaflet tissue where required. A mitral annuloplasty ring reinforces the repair. The tricuspid valve is subsequently repaired by annular plication and leaflet suture. A tricuspid ring is necessary to maintain efficient remodeling. The six patients ages ranged from 20 to 70 years. A etiology, was rheumatic in the first case and degenerative in the following. In three cases, sterilised endocarditis was responsible for ruptured chordae and leaflet destruction. The mitral insufficiency was located in a commissural area in 4 cases, and was due to a widespread posterior prolapse in 2. Post-operative control transesophageal echocardiography confirmed the excellent results of the repair and proved that, in selected cases, the tricuspid leaflet inserted onto the mitral apparatus is very efficient in correcting mitral insufficiency, without causing significant tricuspid impairment. With a 3 to 7 month follow-up, the results are stable.  相似文献   

8.
In order to shed light on the clinical picture of patients with Tourette syndrome (TS) treated at medical institutions in Japan, a nationwide survey covering both pediatric patients and psychiatric patients was conducted. We mailed 316 questionnaires on experience in treating TS cases and the patients' present conditions etc. to specialists such as psychiatrists and pediatricians. A total of 164 responded. The survey found 154 TS patients being treated at the time of survey, 45 (29.2%) had obsessive-compulsive symptoms (OCS), and 10 (6.5%) had family histories of TS. It was suggested that TS is often associated with OCS and that familial cases of TS are slightly less common in Japan than they are in the USA. Of the 116 respondents who described their experiences, 85 (73.2%) said that they had treated one or more patients displaying the symptoms of frequent coprolalia, and 42 (36.2%) said that they had treated one or more patients suffering from developmental disorders. Based on these findings, we speculated that the rate of coprolalia in Japan is a little higher than the previously reported 4% and that TS is often associated with developmental disorders.  相似文献   

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The technical and professional issues that affect the clinical utility of intraoperative frozen section diagnosis in head and neck surgery are addressed from a quality assurance perspective. The most common reasons for sampling errors and interpretive errors are discussed. We offer several recommendations for head and neck surgeons and pathologists which will optimize the clinical utility of intraoperative frozen section consultation.  相似文献   

11.
Deep venous thrombosis (DVT) and pulmonary embolism (PE) are an important cause of morbidity and mortality in the surgical patient. The first guideline produced by the Scottish Intercollegiate Guidelines Network was for the prophylaxis of venous thromboembolism. Patients undergoing major head and neck cancer surgery commonly exhibit risk factors for venous thromboembolism. Currently, however, there are no data on its incidence in these patients. A questionnaire survey was performed to assess the current practice of consultant otolaryngologists regarding DVT prophylaxis in patients undergoing head and neck cancer surgery. Of those respondents who managed these patients, 57 per cent did not use routine DVT prophylaxis while 43 per cent did. A wide variety of techniques were employed among those practising DVT prophylaxis. A consensus is needed concerning the use of thromboembolism prophylaxis in head and neck surgery patients.  相似文献   

12.
Exfoliated cervical epithelial cells from women 6 weeks postpartum were analyzed for human papillomavirus (HPV) DNA using the polymerase chain reaction, and results were compared with those from buccal mucosal smears from their babies. Eleven mothers had genital genotypes of HPV in their cervical smears, and the children of 8 of these had HPV of the same genotype in buccal mucosal cell samples. Nineteen mothers had no HPV DNA detected in their cervical smears, and 1 of the buccal mucosal cell samples from their children was positive for HPV DNA (p < 0.0001). Contamination of a child's mouth with 'genital' HPV from a mother's cervix appears to occur commonly at birth or in the perinatal period, and to persist for at least 6 weeks. This observation has implications for the epidemiology and management of HPV associated cancer and precancerous conditions in the cervix and the mouth.  相似文献   

13.
Patients with locally advanced head and neck tumors were treated +/-amifostine (200 mg/m2, i.v.) before radiotherapy (5x 2 Gy, for 6 weeks). A significant decrease in side effects (p=0.034) using the oral assessment score and duration of mucositis (p=0.02) in the amifostine group was observed. Amifostine is feasible and effective, decreasing acute and late side effects in patients with head and neck tumors.  相似文献   

14.
MUC18/MCAM is a cell-surface glycoprotein that is strongly expressed on advanced human melanomas. Transfection of 3 MCAM-negative melanoma cell lines with MCAM cDNA led to cell-surface expression and to a MCAM-dependent homotypic adhesion. This adhesion was independent of divalent cations and was inhibited at 4 degrees C. Mixed aggregation assays with MCAM-expressing and non-expressing cells revealed that MCAM can function as a heterophilic cell adhesion molecule interacting with a non-MCAM ligand. Although MCAM contains a potential glycosaminoglycan-binding site, cell-surface glycosaminoglycans do not appear to be involved in the heterophilic adhesion observed here since these molecules were not able to influence the adhesion. Using a functional adhesion assay, 4/4 melanoma cell lines examined were found to express an MCAM ligand. In contrast, no evidence for an MCAM ligand was found on the 2 carcinoma or 2 hematopoietic cell lines examined. Stable transfection of an MCAM ligand-negative colorectal cell line resulted in MCAM surface expression but not in homotypic adhesion, indicating that homophilic MCAM-MCAM adhesive interactions may not occur. Our results suggest that MCAM expression by melanoma cells is associated with increased homotypic adhesion, an event that may support tumor cell survival and growth in vivo.  相似文献   

15.
The aim of this pilot study was to explore the prognostic relevance of cell kinetics parameters on the local control of patients affected by head and neck squamous cell carcinoma (HN-SCC), randomly assigned to receive either alternating chemoradiotherapy or partly accelerated radiotherapy. Between 1992 and 1995, 40 patients with HN-SCC at stages III and IV entered the study. Multiple primary tumor biopsies were obtained 6 h after in vivo infusion of bromodeoxyuridine, an analogue of thymidine that is incorporated in DNA-synthesizing cells. In vivo S-phase fraction labeling index (LI), duration of S-phase (TS), and potential doubling time (Tpot) were obtained by analysis of the flow cytometric content of bromodeoxyuridine and DNA. Twenty patients were treated by alternating chemotherapy and conventional radiotherapy (arm A), whereas 20 other matching patients received partly accelerated radiotherapy alone (arm B). Univariate local control analysis showed that LI, TS, and Tpot were not prognostically significant in either arm. However, local control probability at 2 years for fast growing tumors, characterized by a LI of 9%, was higher for patients treated with alternating chemoradiotherapy than it was for those treated with partly accelerated radiotherapy alone (68 versus 39%). Conversely, local control probabilities for slow proliferating tumors (LI, <9%) treated in the two arms were similar. These results suggest a potential role for alternating chemotherapy and radiotherapy in HN-SCC patients with fast growing tumors.  相似文献   

16.
A case of partial trisomy 2(q21q33) detected by cordocentesis at 27 weeks' gestation in a polymalformed fetus is described. This is the second case of a prenatally detected de novo duplication of 2q and the first involving the region referred to above.  相似文献   

17.
The arachidonic acid metabolites, or eicosanoids, are a large series of lipid-derived mediators capable of producing a multitude of physiologic effects in the local environment. They play important roles in a variety of signaling pathways in endocrinology, immunology, and oncology. A significant body of work in this area has occurred in squamous cell carcinomas of the head and neck over the past 15 years. This review will attempt to familiarize the head and neck surgical oncologist with the basic biochemical steps in the formation of these compounds, newer developments in the field of eicosanoid biochemistry, and related experimental evidence of the roles of these substances in head and neck cancer.  相似文献   

18.
One hundred and seventy-eight patients underwent surgical therapy for oral and cervical cancers from 1964 to 1975. About 25 percent of the patients underwent neck dissection and/or "pull-through" procedures. However, majority of patients required a spectrum of reconstructive techniques extending from marginal mandibulectomy with or without skin flaps (39), partial mandibulectomy with immediate prosthetic mandible reconstruction (36), to extended resections with skin flaps or staged reconstructive procedures (48). The advantages and disadvantages of each reconstructive procedure have been observed and a scheme of graded management has been developed. The therapeutic goal is to maximize functional oral reconstruction without compromising tumor cure. There were two operative deaths--one from myocardial infarction after operation and one from halothane hepatitis. The tumors were grouped according to TNM classification. In the follow-up of the 178 patients, 47 per cent are known to be alive and free of tumor. The better results (greater than 70% free of tumor) are in the group with smaller tumors (less than 2 cm.) and no node involvement, and there are less favorable rates for those patients with larger tumors and nodal metastasis or invasion of adjacent structures. There was a 49 percent 2 year survival rate and 12 of the deaths were from nontumor causes. Ninety percent of these patients smoked more than one pack of cigarettes per day, accounting for the high rate of synchronous or subsequent oroairway cancers (7 percent). Seventy-five percent were considered to be "heavy alcoholics" with evidence of cirrhotic liver disease. These two factors significantly decreased the survival from rate 54 to 47 percent. The series shows that planned primary reconstructive surgery can be done at a low risk, that it can enhance resectability of head and neck cancers, and that it does improve oral function after operation.  相似文献   

19.
Three cases of diffuse subcortical gray matter heterotopias in children are reported. Generalised seizures and mild mental retardation were the most frequent signs. No specific electroencephalographic pattern was recognized. Magnetic resonance imaging scans showed the thick diffuse layer of heterotopic gray matter which was surrounded by normal white matter. Gyration was normal, and no associated malformation was observed. This neuronal migrational disorder happens between the 10th and 16th gestational week. Nineteen observations (17 girls) are reported in the literature. The filiation with agyria-pachygyria and the possible genetic transmission are discussed.  相似文献   

20.
Osseointegrated implants can be used to facilitate retention stability and support for facial and intraoral prostheses used to restore head and neck defects. Preliminary studies indicate that in nonirradiated maxillectomy patients the success rates are about 75%. In the reconstructed mandible the results appear to be more favorable--over 90% for implants placed in free nonvascularized bone grafts and over 90% for free revascularized bone grafts. Similar high success rates have been observed for most sites used to support facial prostheses. Success rates for auricular sites exceed 95% and for floor of nose sites success rates exceed 90%. Success rates have been lower (77%) for implants placed in the frontal bone for retention of orbital prostheses. Success rates for irradiated bone sites have been lower and range from 60.4% in the maxilla to 68.6% in facial bone sites. Of greater concern is that most implants placed in irradiated sites are beginning to show signs of impending failure.  相似文献   

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