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OBJECTIVE: This study aimed to compare the results of pressure phosphene tonometry, a new tonometric technique, with Goldmann applanation tonometry. DESIGN: Comparative case series. PARTICIPANTS: A total of 100 consecutive patients (192 eyes) without diagnostic specificity, plus a separate subset of 14 eyes with intraocular pressure (IOP) above 19 mmHg, participated. INTERVENTION: Intraocular pressure was measured with Goldmann tonometry by one examiner and pressure phosphene tonometry by a different examiner. There was no communication between the examiners regarding test results. MAIN OUTCOME MEASURES: Intraocular pressure. RESULTS: In the group without diagnostic specificity, the mean difference between the two techniques was 0.3 mmHg. Fifty-one percent of the measurements were within +/-1 mmHg, 74.9% of the measurements were within +/-2 mmHg of each other, and the average deviation for 100% of the data was 1.8 mmHg. For pressure phosphene tonometry, the mean IOP was 15.2 mmHg with a standard deviation of 2.9 and a range of 18 mmHg (minimum, 10; maximum, 28). With Goldmann, the mean was 15.5 mmHg, the standard deviation was 3.1, and the range was 20 mmHg (minimum, 8; maximum, 28). The t test for paired data showed a Gaussian approximation with a P value of 0.05. A comparison between the results of the two techniques gave a correlation coefficient of 0.71. Results for the separate 14 patients with higher IOPs yielded a statistically significant mean difference of 0.1 mmHg between the two techniques (P < 0.05, t test for paired data). For pressure phosphene, the mean was 21 mmHg with a standard deviation of 5.5 and a range of 24 mmHg (minimum, 14; maximum, 38). For Goldmann, the mean was 21.1 mmHg with a standard deviation of 4.7 and a range of 19 mmHg (minimum, 15; maximum, 34). The correlation coefficient was 0.73. CONCLUSIONS: The close agreement between the two techniques suggests that pressure phosphene tonometry offers an alternative method for measuring IOP. It has the advantages that it is simple, noninvasive, and inexpensive. Potential uses of the pressure phosphene tonometer may include self-administered home testing, in outreach clinics by nonophthalmic technicians, and in patients with corneal conditions that preclude the use of Goldmann tonometry.  相似文献   
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As the initial stage in developing a curriculum to assist family physicians to diagnose and manage alcohol abuse in their practices, questionnaires were mailed to a selected group of family physicians. A total of 117 physicians (34%) completed the questionnaire. The majority of physicians (70.1%) reported that fewer than 10% of their caseload experienced alcohol-related problems. Most physicians (59.3%) did not use any of the standard diagnostic instruments but reported that screening and detection was the most challenging alcohol-related problem along with patient management. The questionnaire identified a number of areas that could be used in the development of educational strategies to increase the expertise of primary care physicians in the diagnosis and management of alcohol-related problems.  相似文献   
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STUDY OBJECTIVE: Part 1: To measure ropivacaine levels in the mother and infant at delivery after continuous lumbar epidural infusion. Part 2: To compare epidural ropivacaine to epidural bupivacaine for labor analgesia in regard to effectiveness, motor blockade, and maternal and neonatal effects. DESIGN: Part 1: Open-labelled, non-blind study. Part 2: Randomized, double-blind study. SETTING: Labor and delivery units of two academic hospitals. PATIENTS: Part 1: 20 ASA physical status I and II parturients in active labor. Part 2: 81 ASA physical status I and II parturients in active labor. INTERVENTIONS: For Part 1, 8 to 12 ml of 0.25% ropivacaine was administered through a lumbar epidural catheter to achieve a T10 dermatomal sensory level. An infusion of 0.25% ropivacaine, 8 to 10 ml/hr, maintained this sensory level. Maternal and umbilical cord blood samples obtained at delivery were analyzed for ropivacaine concentration. For Part 2, anesthetic management was similar to that previously described except patients were randomized to receive either 0.25% ropivacaine or 0.25% bupivacaine. Onset, regression, maximal spread of sensory block, and onset and degree of motor blockade were measured. Contraction pain as assessed using a visual analog scale (VAS), maternal blood pressure, and heart rate were determined every 5 minutes until a stable VAS-contraction score was achieved, and every 30 minutes thereafter. Neonatal assessment included Apgar scores and neurologic and adaptive capacity scores (NACS) at 15 minutes, 2 hours, and 24 hours. MEASUREMENTS AND MAIN RESULTS: For Part 1, the total and free maternal arterial concentrations of ropivacaine at delivery were 0.64 +/- 0.14 microgram/ml and 0.10 +/- .02 microgram/ml, respectively; the umbilical venous total and free concentrations were 0.19 +/- 0.03 microgram/ml and 0.12 +/- 0.07 microgram/ml, respectively (n = 12). The umbilical arterial and venous concentrations did not differ for both the free and total concentrations. For Part 2, there was no difference between ropivacaine and bupivacaine in the variables measured. Umbilical cord gases and Apgar scores were not different between the two groups; NACS were higher at 15 minutes and 2 hours in the ropivacaine group (p < 0.05) than the bupivacaine group. CONCLUSION: Both ropivacaine and bupivacaine produced excellent analgesia for labor with no major adverse effect on the mother or neonate.  相似文献   
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This study examined the effects of cardiomyoplasty with vascular delay on canine normal and depressed left ventricular (LV) function. To improve viability of the latissimus dorsi muscle (LDM), vascular delay was performed 2 weeks before cardiomyoplasty in 10 mongrel dogs. Two weeks after cardiomyoplasty, LV function was evaluated by simultaneously measuring LV and aortic pressure, and aortic flow. The LDM was stimulated at a ratio of 1:4-1:7 synchronously with ventricular systole. Microspheres (90 mu) were sequentially injected into the left coronary artery to depress LV function. Data were acquired and analyzed on a beat to beat basis. Results were as follows: LDM stimulation significantly augmented LV systolic pressure (LVSP) from 138 +/- 2 to 161 +/- 2* mmHg, the peak rate of change of LV pressure (+dP/dt) from 1888 +/- 46 to 2584 +/- 43* mmHg/sec, aortic systolic pressure (AoSP) from 140 +/- 2 to 159 +/- 2* mmHg, stroke volume (SV) from 11.2 +/- 0.3 to 13.3 +/- 0.3* ml, stroke work (SW) from 19 +/- 1 to 26 +/- 1* gm.m, peak aortic flow (P Qa) from 5542 +/- 142 to 7190 +/- 161* ml/min, and decreased -dP/dt from -1683 +/- 31 to -1689 +/- 49* mmHg/sec (* = p < 0.05). Microsphere injections depressed LV function, but did not affect the magnitude of the net changes between stimulated and nonstimulated beats. However, the percent changes significantly increased. Preconditioning of LDM with vascular delay augments cardiac function in LDM assisted beats. This improved performance was present in both normal as well as depressed LV function groups. Thus, investigations of cardiomyoplasty may not necessarily require a model of severe myocardial dysfunction. Vascular delay offers an important preconditioning method of LDM to augment cardiac function in cardiomyoplasty.  相似文献   
78.
The present investigation was designed to examine the effects of sympathetic nervous system (SNS) inhibition on sexual behavior in ovariectomized, steroid-treated female rats. Clonidine, an alpha2-adrenergic agonist, guanethidine, a postganglionic noradrenergic blocker, and naphazoline, an alpha2-adrenoreceptor agonist were used to inhibit SNS activity. Intraperitoneal injections of either 33 micrograms/ml or 66 micrograms/ml clonidine significantly decreased receptive (lordosis) and proceptive (ear wiggles) behaviors and significantly increased rejection behaviors (vocalization, kicking, boxing). Either 25 mg/ml or 50 mg/ml guanethidine significantly decreased receptive and proceptive behavior and had no significant effect on rejection behaviors. Naphazoline significantly inhibited lordosis behavior at either 5 mg/ml or 10 mg/ml doses, significantly inhibited proceptive behavior at 5 mg/ml, and had no significant effect on rejection behaviors. These findings support the hypothesis that SNS inhibition decreases sexual activity in the female rat.  相似文献   
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Creatine kinase (CK) provides ATP buffering in skeletal muscle and is expressed as 1) cytosolic myofibrillar CK (M-CK) and 2) sarcomeric mitochondrial CK (ScCKmit) isoforms that differ in their subcellular localization. We compared the isometric contractile and fatigue properties of 1) control CK-sufficient (Ctl), 2) M-CK-deficient (M-CK[-/-]), and 3) combined M-CK/ScCKmit-deficient null mutant (CK[-/-]) diaphragm (Dia) to determine the effect of the absence of M-CK activity on Dia performance in vitro. Baseline contractile properties were comparable across groups except for specific force, which was approximately 16% lower in CK[-/-] Dia compared with M-CK[-/-] and Ctl Dia. During repetitive activation (40 Hz, (1)/(3) duty cycle), force declined in all three groups. This decline was significantly greater in CK[-/-] Dia compared with Ctl and M-CK[-/-] Dia. The pattern of force decline did not differ between M-CK[-/-] and Ctl Dia. We conclude that Dia isometric muscle function is not absolutely dependent on the presence of M-CK, whereas the complete absence of CK acutely impairs isometric force generation during repetitive activation.  相似文献   
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