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121.
To determine whether pollen produced by maize (Zea m. mays) may contribute to the development of larval Anopheles gambiae complex mosquitoes, the main African vectors of malaria, we correlated duration of larval development, pupation success, and size of the resulting adults with degree of access to this potential nutriment. Maize pollen is abundant during the wet season on the surface of water near maize plantings in a malaria-endemic region of Ethiopia, and larval Anopheles arabiensis readily ingest these particles in nature. Larvae develop to the pupal stage more rapidly, more frequently, and produce larger adults where maize pollen is abundant than do those that have little access to this food. The force of transmission of malaria in sub-Saharan Africa might be reduced if maize plantings were excluded from the immediate vicinity of homes or, perhaps, if pollen of such maize were to express entomotoxins.  相似文献   
122.
Eight children aged between 1.3 and 13 years suffering from epilepsy refractory to conventional anticonvulsive therapy were treated with high dose intravenous gamma globulin (200 mg/kg, 3 times per week, repeated after 3 weeks). Immunological studies after therapy showed normal results. In four children, clinical and EEG findings markedly improved. In one other case a partial response was noted. No improvement was observed in the remaining three cases. We confirm that although the mechanism is still obscure, high doses of i.v. gammaglobulin may have a beneficial effect in a significant number of children with intractable epilepsy.  相似文献   
123.
124.
Perineal endometriosis. A case report   总被引:3,自引:0,他引:3  
Perineal endometriosis was found unexpectedly in a 32-year-old woman with primary infertility. Since there had been no prior perineal trauma, the transport of endometrium through a venous or lymphatic route could have accounted for the location of the endometriosis.  相似文献   
125.
The purpose of this study was to determine whether magnesium sulfate and promethazine interact to cause hypotension in gravid ewes. Fifteen experiments were performed in five chronically instrumented animals between 125 and 130 days of timed gestation (term = 145 days). In one group of experiments each animal received magnesium sulfate (4 gm intravenous bolus followed by 4 gm/hr intravenous infusion) then promethazine (50 mg intravenously). In a second group each animal received magnesium sulfate then saline solution as a control. In a third group each animal received saline solution then promethazine. Infusion of magnesium sulfate increased the mean (+/- SEM) serum magnesium concentration to 5.7 +/- 0.6 and 6.6 +/- 0.6 mg/dl in the magnesium sulfate-promethazine and magnesium sulfate-saline solution groups, respectively. Magnesium sulfate slightly decreased maternal mean arterial pressure (p less than 0.05) and increased cardiac output (p less than 0.05) in both the magnesium sulfate-promethazine and magnesium sulfate-saline solution groups. Otherwise there were no significant changes in maternal mean arterial pressure or cardiac output in any group. Promethazine increased maternal heart rate (p = 0.0001) in both the magnesium sulfate-promethazine and saline solution-promethazine groups. Magnesium sulfate increased uterine blood flow (p less than 0.01) in both the magnesium sulfate-promethazine and magnesium sulfate-saline solution groups, but promethazine blunted the increase in uterine blood flow associated with magnesium sulfate. Similarly, magnesium sulfate decreased uterine vascular resistance (p less than 0.01) in both the magnesium sulfate-promethazine and magnesium sulfate-saline solution groups, but promethazine eliminated the decrease in uterine vascular resistance associated with magnesium sulfate. Maternal and fetal arterial blood gas and acid-base values did not change in any group, except that there was a small, near-significant decrease (p = 0.06) in fetal pH 10 minutes after promethazine was given in the magnesium sulfate-promethazine group. We conclude that magnesium sulfate and promethazine did not interact to cause maternal hypotension in normovolemic gravid ewes. However, promethazine increased maternal heart rate and blunted the increase in uterine blood flow associated with magnesium sulfate.  相似文献   
126.
The Programme of Action of the International Conference on Population and Development 1994 enshrines an almost-feminist vision of reproductive rights and gender equality in place of the old population control discourse but retains a mainstream model of development under which that vision cannot possibly be realised. This ‘fault line’ is highly dangerous for feminists, because it configures a gap between the politics of the body, sexuality and reproduction and the politics of social development and global economic transformation. An analysis that makes explicit the concrete links between macro-economic policies and the materialisation of reproductive and sexual rights for all the world's women is needed.  相似文献   
127.
OBJECTIVE: To determine whether topical aqueous suppressant therapy applied after pars plana vitrectomy with gas tamponade prevents postoperative intraocular pressure (IOP) elevation. DESIGN: Prospective, nonrandomized comparative study. PARTICIPANTS: Forty-one patients who met inclusion criteria and underwent pars plana vitrectomy with gas tamponade (SF6 18%-20% or C3F8 12%-16%) over a 1-year period. INTERVENTION: Treatment eyes received topical aqueous suppressants at the end of surgery. MAIN OUTCOME MEASURES: Postoperative IOP at 4 to 6 hours, 1 day, and 1 week. RESULTS: Twenty-one control and 20 treatment eyes met the inclusion criteria. The IOP (in mmHg) measured at 4 to 6 hours (23.05 [control, 14.73 [treatment]) and 1 day (23.24 [control], 17.28 [treatment]) postoperatively showed a statistically significant difference between the groups (P = 0.0038) at 4 to 6 hours and a trend toward significance (P = 0.057) at 1 day. Eleven control and three treatment eyes had an IOP spike above 25 mmHg at 4 to 6 hours or 1 day postoperatively (P = 0.02), and six control eyes and one treatment eye had postoperative IOP greater than 30 mmHg. A pressure rise greater than 40 mmHg was seen in two control eyes and no treatment eyes. CONCLUSIONS: Use of topical aqueous suppressants after pars plana vitrectomy with long-acting gas tamponade is effective in preventing significant postoperative IOP elevation in most cases.  相似文献   
128.
Serial cardiopulmonary variables were recorded over 4 days in 23 children with severe acute respiratory failure. In all patients, pulmonary artery catheters were inserted within 24 hours of the diagnosis of respiratory failure, and all required greater than 10 cm H2O positive end-expiratory pressure to achieve adequate oxygenation. Eight patients died (35% mortality). Evaluation of systemic hemodynamic variables indicated that survivors had higher blood pressures than nonsurvivors, although neither group was in the hypotensive range. Systemic vascular resistance was lower in the nonsurvivors. Cardiac function as evaluated by cardiac index, right ventricular stroke work index, and left ventricular stroke work index was similar in both groups. Survivors demonstrated elevations in mean pulmonary artery pressure and pulmonary vascular resistance during the first 36 hours, with gradual improvement thereafter. In contrast, pulmonary artery pressure and resistance increased progressively in patients who died. Intrapulmonary shunt fractions remained high in the nonsurvivors despite the use of up to 25 cm H2O PEEP. Cardiac function and oxygen delivery were well maintained in both groups despite the high levels of PEEP.  相似文献   
129.
PURPOSE: To determine how glaucoma and glaucoma suspect patients' rating of their vision correlates with Esterman binocular visual field testing and other visual function tests. METHODS: One hundred ninety-one glaucoma patients and 46 glaucoma suspect patients underwent binocular visual field testing and evaluated their vision using the linear rating scale and time-tradeoff utility tests, the National Eye Institute Visual Functional Questionnaire (NEI VFQ-25), and the Short Form 36 (SF-36) quality-of-life instruments. RESULTS: The mean Esterman score was 88.2 +/- 17.4 for the glaucoma subjects and 95.2 + 6.9 for glaucoma suspect subjects (maximum score 100). On a scale from 0 (blind) to 100 (ideal), the mean rating of vision for glaucoma patients and glaucoma suspect patients was 74.8 +/- 17.3 and 78.9 +/- 18.5, respectively. The Esterman test correlated moderately with the overall NEI VFQ-25 score (partial correlation coefficient (PCC) = 0.32, P = 0.001), but only weakly with the linear rating scale (PCC = 0.17, P = 0.02), and the time-tradeoff (PCC = 0.14, P = 0.06). CONCLUSION: Utility values that glaucoma and glaucoma suspect patients assign to their vision do not correlate well with Esterman results. A challenge for the future is the design of clinical tests of vision that better correlate with patient perceptions.  相似文献   
130.
PURPOSE: To describe the clinical features of central serous chorioretinopathy (CSC) in women and identify factors predictive of complete recovery, moderate visual loss, and prolonged duration. DESIGN: Retrospective observational case series. PARTICIPANTS: Eighty-four eyes in 78 women with CSC seen in our practices between 1982 and 1999. METHODS: Univariate and multivariate statistical analysis. MAIN OUTCOME MEASURES: Analyses of three outcome parameters: complete recovery (recovery of visual acuity and complete symptom resolution), moderate visual acuity loss (final acuity less than 20/40), and duration of symptoms greater than 5 months. RESULTS: Sixty-two percent (52 of 84) achieved complete recovery over a median of 5 months (range, 2-108 months) and 88% (74 of 84) had a final vision of 20/40 or better. Patients with subretinal precipitates (P = 0.001), single occurrence (P = 0.002), absence of hormone replacement therapy (HRT) (P = 0.01), duration less than 5 months (P = 0.02), or absence of a pigment epithelial detachment (PED) (P = 0.05) were more likely to recover completely. Recurrence (P = 0.03) and lack of subretinal precipitates (P = 0.03) were associated with a final vision less than 20/40. Age older than 50 (P = 0.004) and the presence of a PED (P = 0.02) were associated with duration longer than 5 months. CONCLUSIONS: In women, CSC associated with subretinal precipitates, shorter duration, single occurrence, lack of HRT use, and absence of PED is more likely to resolve completely. CSC occurring in women older than 50 or associated with PED formation is more likely to take longer to resolve.  相似文献   
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