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91.
Ocular neuromyotonia (ONM) is a rare disorder characterized by episodic diplopia, occurring either spontaneously or following sustained eccentric gaze. Most patients have had prior radiation therapy to the sellar and parasellar region. ONM is thought to reflect impaired muscle relaxation due to inappropriate discharges from oculomotor, trochlear, or abducens neurons or axons with unstable cell membranes. Patients with ONM often benefit from membrane stabilizing agents such as carbamazepine. Here we describe a 71-year-old man, with no history of radiation therapy, who for 18 months had had transient episodic diplopia that occurred after down gaze. Clinical examination indicated ONM in muscles supplied by the right oculomotor nerve. Binocular scleral search coil eye movement recordings revealed a defect not only of muscle relaxation but also of maximal muscle contraction. The patient was treated with carbamazepine 200 mg per day with complete resolution of his symptoms. ONM may be more common than previously recognized, and patients with unexplained transient episodic diplopia should be specifically tested for diplopia and ocular misalignment following sustained eccentric gaze.  相似文献   
92.
OBJECTIVES: To affirm the feasibility of using intermittent androgen suppression in patients with hormone-naive prostate cancer. METHODS: Leuprolide and flutamide were administered for 9 to 12 months and then discontinued until prostate-specific antigen (PSA) levels reached a threshold value determined by the baseline PSA value. This constituted one cycle of treatment. Androgen suppression was then administered intermittently as described until there was evidence of androgen independence. RESULTS: Twenty-two patients with PSA failure after primary therapy with surgery and/or radiation and untreated early or Stage D2 disease were treated. Twenty-one patients completed androgen suppression during cycle 1, with a median time to PSA nadir of 3.5 months (range, 2 to 12). Fifteen patients completed cycle 1 with a median time off treatment of 6 months (range, 2 to 19) or 38% (range, 17% to 64%) of a treatment cycle. Six patients continued off treatment during cycle 1 for 1+ to 31+ months. During cycle 2, 12 patients achieved a PSA nadir in a median time of 3.5 months. Two patients completed cycle 2 with a median time off treatment of 10 months (51%). Median follow-up for all patients is 26 months (range, 10 to 51). While off treatment, all patients reported a reduction of symptoms associated with androgen suppression. CONCLUSIONS: Intermittent androgen suppression is a feasible alternative to continuous androgen suppression for treatment of prostate cancer, and quality of life is improved while off treatment.  相似文献   
93.
OBJECTIVE: To determine if poor dietary intake can explain the cobalamin-related abnormalities often seen in the elderly. DESIGN: Prospective laboratory survey with a follow-up dietary assessment. SETTING: Social centers for the elderly and an outpatient clinic. SUBJECTS: Ninety-five free-living subjects >60y old with abnormal or suspicious findings in cobalamin-related tests and 78 subjects >60y old with normal results. INTERVENTIONS: Serum cobalamin, methylmalonic acid and homocysteine determinations to assess cobalamin status and a one year food-frequency questionnaire to assess cobalamin intake. RESULTS: Only three of the 173 subjects (1.7%), one of whom had normal cobalamin status, ingested <2 microg cobalamin/d, the Recommended Daily Allowance. Sixty-nine subjects (39.9%) ingested <6 microg/d, but they did not have more abnormal serum cobalamin or metabolite values than those ingesting >6 microg. Ordering all subjects by quintiles according to cobalamin intake revealed no significant trends or differences in any of the serum values either. Moreover, arranging subjects by results of tests of cobalamin status showed that the subjects with abnormal cobalamin status did not differ in cobalamin intake from those with normal cobalamin status, although they did differ in use of supplements. Finally, cobalamin intake, with or without supplements, did not correlate with serum cobalamin or metabolite levels. The absence of any association between cobalamin status and intake contrasts sharply with the significant correlation between folate intake and folate status (P = 0.0001). CONCLUSIONS: The high frequency of mildly abnormal cobalamin status in the elderly cannot be attributed to poor intake of cobalamin. Nondietary explanations, such as malabsorption and other phenomena, must always be sought to explain mild cobalamin deficiency in the elderly.  相似文献   
94.
Allergic rhinitis has been conservatively estimated to affect 35 million Americans, with an annual US expenditure of more than $2 billion for treatment. Immunotherapy is generally administered to patients with allergic rhinitis when avoidance is impossible or impractical, when pharmacotherapy provides insufficient relief, and/or symptoms span more than one season. Immunotherapy based on quantified testing (e.g., dilutional intradermal testing [SET] or in vitro methods [RAST, ELISA]) allows administration of antigens in a manner that achieves therapeutic antigen doses more rapidly, yet more safely than immunotherapy administered through a schedule that mixes all antigens at the same concentration and advances on an empirical basis. Sixty patients who received at least one year of quantified testing-based immunotherapy were evaluated using a quality of life questionnaire and individual interviews. Changes in physical, social and emotional well-being were determined. Also investigated were changes in productivity and medication usage. The majority of patients noted significant improvement in all areas within four to six months of initiating immunotherapy, and an overwhelming majority felt that such treatment represented a worthwhile investment of their time and money.  相似文献   
95.
The present study was undertaken to determine the conditions under which acute periods of hemorrhagic shock induce bacterial translocation. Rats (at least six per group) were anesthetized intraperitoneally with the barbiturate, pentobarbital (50 or 65 mg/kg), or the inhalation anesthetic methoxyflurane. Following anesthesia, the femoral artery was catheterized, from which blood was withdrawn to maintain a mean arterial blood pressure of 30 mmHg for 30, 60, or 90 min, followed by reinfusion of shed blood. Instrumented, but nonshocked animals served as controls. Rats were sacrificed at 0, 2, or 24 hr postshock, and quantitative bacterial cultures of the mesenteric lymph node complex (MLN), liver, and spleen were made. Within groups, the effects of heparinization were also determined. In pentobarbital-treated animals, regardless of the extent of heparinization, consistent translocation to both MLN and distant organs occurred when shock was prolonged for 90 min, and assessment of translocation was made 24 hr after reinfusion of shed blood. Furthermore, a mortality rate of approximately 30% was found in rats subjected to this protocol. The magnitude of translocation was less consistent, and did not differ from that in sham shock controls, under other conditions of shock and evaluation. In rats anesthetized with methoxyflurane, no mortality occurred, and no statistical significance between the incidence or degree of translocation in shocked animals vs. sham shock controls could be demonstrated, regardless of the shock protocol. In additional studies, effects of these anesthetics on intestinal morphology and superior mesenteric arterial (SMA) flow in the context of hemorrhagic shock were assessed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
96.
To examine the value of transient regional asynergy on dobutamine stress echocardiography as a noninvasive predictor of future cardiac events, 51 symptomatic patients (aged 54 +/- 9 years) with suspected coronary artery disease (CAD) were studied using an incremental regimen of 5, 10, 15 and 20 micrograms/kg/min. Pretest likelihood of CAD was (mean +/- standard error of the percentage) 79.7 +/- 5.6% before and 83.4 +/- 5.2% after exercise electrocardiography using probability analysis based on age, sex and symptoms. Two-dimensional images were analyzed with reference to an 11-segment model and gave good interrater agreement. During 24 +/- 4 months (range 19 to 32) of follow-up, 23 patients had events (1 myocardial infarction, 9 unstable angina, 10 coronary bypass surgery, 3 coronary angioplasty) and 28 were event free. Age, proportion with baseline asynergy and both pretest echocardiographic ejection fraction and its response to dobutamine were similar in these 2 groups (all p = not significant). Transient asynergy was seen in 17 of 23 patients (74%) with and 8 of 28 patients (29%) without events (p < 0.01); 5 of 6 patients (83%) with involvement of 3 segments had events. Myocardial infarction or unstable angina occurred in 8 of 25 (32%) with a positive and 2 of 26 (8%) with a negative stress echocardiogram (p < 0.05). Both exercise duration (389 +/- 195 vs 517 +/- 237 seconds, p < 0.05) and time to diagnostic ST-segment shift (291 +/- 192 vs 447 +/- 212 seconds, p = 0.05) were shorter in those with inducible asynergy.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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98.
Pre-eclampsia is a disease that can affect several organs and systems. Neurologic repercussions are particularly feared, provoking, among other manifestations, seizures and blindness. Imaging techniques are available to elucidate the pathogenesis of this complication, also allowing us to diagnose other brain lesions: CT, MRI and transcranial Doppler. The authors present some aspects of imaging techniques related to the neurologic complications in preeclampsia/eclampsia.  相似文献   
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