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991.
The Mazzotti reaction is a frequent complication in patients with onchocerciasis being treated with diethylcarbamazine (DEC); and more severe manifestations of this reaction may be unacceptable in many patients. It has recently been demonstrated that prednisone modifies the severity of this reaction and reduces the microfilaricidal activity of DEC. A clinical trial was performed at the National Leprosy Training Center in Wau, Sudan, to evaluate the clinical and histologic effect of the use of corticosteroids in patients receiving DEC. Administration of a low dose of dexamethasone (3 mg/day), begun after onset of the Mazzotti reaction, modifies the progression of the Mazzotti reaction without interfering with the microfilaricidal efficacy of DEC. Pretreatment with low-dose dexamethasone--prior to beginning DEC therapy--prevents the development of the Mazzotti reaction and greatly reduces the microfilaricidal activity. Administration of diphenhydramine, after onset of the Mazzotti reaction, has no effect on the course and intensity of the Mazzotti reaction nor on microfilaricidal activity. We recommend that low-dose corticosteroids be administered in conjunction with DEC--after onset of the Mazzotti reaction--and that they be tapered rapidly.  相似文献   
992.
The traditional pelvic examination is often viewed by patients with mixed feelings, and there are reasons to believe that enhanced patient knowledge might foster more positive attitudes toward this important aspect of women s health care. One proposed technique in accomplishing this goal is the mirror pelvic examination (MPE). However, there is a paucity of reported clinical experience dealing with this modification of the traditional pelvic examination. Accordingly, a questionnaire was designed to assess attitudes and impressions toward the MPE among a sample of 21 women who were offered the procedure at a metropolitan clinic. This survey revealed the MPE to be well received by patients, both as a method of anxiety reduction and as one of patient education.  相似文献   
993.
Further data on the Gb - HL-A linkage relationship are presented. All three GBG informative recombinants investigated are Gb - first HL-A recombinants; therefore Gb must be situated on the second HL-A side of the first HL-A locus. Ninety additional apparently Gb - HL-A non-recombinant offspring from 23 matings indicate that the Gb locus is situated in clsoe proximity to the second HL-A locus.  相似文献   
994.
A random sample of 501 eligible families was selected from a designated neighborhood in Portland, Oregon, and given the opportunity to join a 5-year intervention program promoting a low-fat and low-cholesterol eating pattern designed to reduce risk for coronary heart disease. Participation entailed three baseline assessments of clinical, dietary, and psychological indices, periodic follow-up measurements, and monthly small group meetings led by psychologists and nutritionists. A prior home health survey allowed comparisons of respondents from joining and nonjoining families in terms of reported health status, health beliefs, health locus of control, knowledge about health and nutrition, and demographic characteristics. Almost half (47%) of all invited families agreed to join this long-term nutrition intervention program and completed the necessary baseline assessments. Factors discriminating joiners and nonjoiners were not generally consistent with the health belief model of preventive health behavior. Joiners were similar to nonjoiners in terms of perceived susceptibility to disease, family health histories, and reports of elevated plasma cholesterol levels in the family. However, families with hypertensive members were less likely to join this heart disease prevention program. Positive predictors of participation included higher occupational status, greater knowledge about heart disease, a more internal health locus of control, and the belief that there are few barriers preventing the adoption of a healthier low-fat eating pattern. These findings indicate that there is widespread community interest in optimal nutrition, and they also provide suggestions as to what motivates the general public to take preventive health actions.  相似文献   
995.
Cardiac Neoplasms: Current Diagnosis, Pathology, and Therapy   总被引:1,自引:0,他引:1  
Cardiac neoplasms remain enigmatic because of their rarity and protean clinical manifestations. Although surgery for benign cardiac neoplasms seems straightforward, certain difficulties in diagnosis and extirpation often exist. Newer diagnostic modalities including intraoperative transesophageal echocardiography seem promising and may provide better planning for the surgeon. Moreover, cardiac transplantation has provided relief for some patients with irresectable benign neoplasms. As ventricular arrhythmias may emanate from benign tumors, electrophysiologically guided extirpation may provide helpful control. Malignant cardiac tumors remain the true challenge, whether primary or metastatic, as little surgical or medical progress has resulted. This review examines nearly all diagnostic, pathological, histologic, and therapeutic aspects of benign and malignant cardiac tumors. Moreover, the various surgical approaches necessary for removal of resectable neoplasms are detailed.  相似文献   
996.
1. We describe the actions of a novel and selective 5-HT1-like receptor agonist, GR43175, in a range of isolated tissue preparations containing different 5-hydroxytryptamine (5-HT) receptor types. 2. GR43175 was a potent agonist at 5-HT1-like receptors mediating contraction of the dog isolated saphenous vein and also at those inhibiting neuronally mediated contractions in the same preparations. For both actions, GR43175 was approximately four times weaker than 5-HT. 3. GR43175 was devoid of agonist properties at 5-HT1-like receptors mediating relaxation of the cat isolated saphenous vein. 4. GR43175 was devoid of agonist properties at 5-HT2 receptors mediating contraction of the rabbit isolated aorta, pig coronary artery, greyhound coronary artery and beagle femoral artery. 5. GR43175 was devoid of agonist properties at 5-HT3 receptors mediating depolarization of the rat isolated vagus nerve. 6. The contractile response to GR43175 in the dog isolated saphenous vein was selectively antagonized by methiothepin but was resistant to antagonism by the 5-HT2 receptor blocking drug ketanserin and the 5-HT3 receptor blocking drug MDL 72222. Methiothepin antagonized the contractile action of 5-HT and GR43175 to an equal extent suggesting that both agonists act at the same receptor. 7. The results demonstrate that GR43175 is a highly selective agonist for the 5-HT1-like receptors found in the dog saphenous vein. The absence of an action of GR43175 at 5-HT1-like receptors mediating relaxation of the cat isolated saphenous vein provides further evidence that 5-HT1-like receptors are heterogeneous.  相似文献   
997.
998.
999.
The sensitizing properties of unsaturated and halogenated sultones were examined in a guinea-pig model for contact hypersensitivity. The sensitization potential of 2-chloro-1,3-dodecanesultone was similar to that of 1-chloro-2,4-dinitrobenzene (DNCB). 2-bromo-1,3-dodecanesultone, 1-decene-1,3-sultone, 1-decene-1,3-sultone, 1-tetradecene-1,3-sultone and 1-hexadecene-1,3-sultone were stronger senistizers than DNCB. Ectensive cross-reactivity was observed among sultones of the same side-chain length, but differing from each other in being either unsaturated or halogenated. Extensive cross-reactivity was also noted among 4 unsaturated sultones of differing side-chain lengths. The inter-relationships among these sultones in regard to their immunogenic and tolerogenic properties are discussed.  相似文献   
1000.
Tendon echogenicity: ex vivo study   总被引:2,自引:0,他引:2  
Crass  JR; van de Vegte  GL; Harkavy  LA 《Radiology》1988,167(2):499-501
Recent publications discussing the echogenicity of normal tendon have described it variously as hyperechoic or hypoechoic. Since the echogenicity of tendon has been used to define normality and abnormality, certain knowledge of the normal echogenicity of tendon is crucial. Fresh tendon and muscle from beef hock was scanned with sector- and linear-array-transducer imaging at multiple angles and distances. The echogenicity of tendon was found to be very angle-dependent, a characteristic known as anisotropy. Scanned perpendicular to its long axis with a linear-array transducer, tendon was significantly more echogenic than muscle. With a change in angle, echogenicity of tendon decreased relative to that of muscle (the echogenicity of muscle remained the same), becoming isoechoic at angles of 2 degrees -7 degrees and hypoechoic at greater angles. Tendon studied with a sector transducer exhibited varying echogenicity. If echogenicity is used as a diagnostic criterion, the angle of the interrogating ultrasound beam must be very specifically defined.  相似文献   
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