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991.
A full-term black boy had a 2- to 3-cm, round, bluish mass on his right lower eye-lid at birth, later diagnosed as rhabdomyosarcoma. It was cystic in nature and extended into the nasal cavity. The tumor was initially classified as neuroblastoma. The child died eitht months later and necropsy report confirmed an original ophthalmologic pathology diagnosis of embryonal rhabdomyosarcoma.  相似文献   
992.
This article reviews new developments in the field of cardiac pacing. Special emphasis is placed on dual chamber temporary pacing, external transthoracic cardiac pacing, and antitachycardia pacing. The role of the automatic implantable cardioverter defibrillator (AICD) in patients with sudden cardiac death is also explored with emphasis on the presentation of such patients to intensive care units.  相似文献   
993.
Left varicocele ligation was performed in 64 infertile men seen at our clinic during 1974–1978. High ligation of the left internal spermatic vein was done in all cases. The ages of patients were 23–46 yr. The criteria for operation were: palpatory findings of varicocele, primary or secondary infertility, and abnormal sperm analysis. Statistical analysis of the 3 main sperm parameters before and after surgery shows a significant increase in sperm count (P < 0.005) and motility index (P < 0.005), while the sperm morphology was not improved (P = 0.2). The pregnancy rate was 43.8%.  相似文献   
994.
24 patients with muscle invasive carcinoma of the bladder were treated in a pilot study of twice daily fractionation at radiation doses of 1.8-2.0 Gy per fraction to total doses of 54-64 Gy to the bladder and 39.6-44 Gy to the whole pelvis. The treatment aim was to give 32 fractions in 22 days. The interfraction interval was a minimum of 6 h. The principle objective was to record acute and late tolerance, but local control and survival data is also presented. Acute radiation morbidity was scored according to the RTOG system. Grade 2 large bowel effects were seen in 52% of patients, Grade 3 effects in 26% and there was one Grade 4 and one Grade 5 effect. The mean duration of effect was 4.5 weeks although the more severe reactions were also more protracted. Grade 2 urinary effects occurred in 30% and Grade 3 in 17% of patients. The mean duration of effect was 7.2 weeks. There were no Grade 4 or 5 acute urinary effects. Late radiation morbidity was scored according to the EORTC/RTOG system and was assessable in 16 cases who survived more than 6 months. There were two cases (12%) of Grade 1 bowel toxicity, two cases of Grade 1 and three of Grade 2 urinary toxicity. There were no cases of late skin effects. Actuarial analysis at 2 years shows a local control probability of 56% and survival probability of 35%.  相似文献   
995.
996.
The present study presents the first analysis of neurons in mammalian brain transplants based on intracellular recording. The results, obtained in brain slices including both donor and host tissue, showed that neuronal precursor cells in embryonic transplantsretained their ability to complete their normal differentiation of cell-type-specific electroresponsive properties. Distortions in cell aggregation and synaptic connectivity did not affect this aspect of neuronal differentiation.  相似文献   
997.
998.
BACKGROUND: Acute tryptophan depletion (ATD), a means of reducing brain serotonin synthesis, lowers mood in normal males with a multi-generational family history of major affective disorder (MAD) and in normal women devoid of any family history of psychiatric illness. As both a family history of MAD and female sex are factors predisposing to depression, the hypothesis that a mood lowering response to ATD may reflect a susceptibility to depression was further investigated in young women with an extensive, multi-generational family history of MAD. In addition, the temporal stability of mood change following repeated trials of ATD was also assessed in this study. METHODS: To deplete tryptophan, a tryptophan deficient amino acid mixture was ingested on two separate occasions. The control treatment, administered on a third occasion, was a nutritionally balanced amino acid mixture containing tryptophan. RESULTS: A marked lowering of plasma tryptophan (85-90 %) was achieved by both depletions. In comparison to the balanced condition, family history positive (FH +) women showed no lowering of mood to either the first or second ATD (N = 13) and N = 12, respectively). Mood change between the two ATD trials (N = 13) exhibited poor temporal stability. CONCLUSIONS: These results may indicate that serotonin responsiveness is not an important characteristic of vulnerability to depression in these women. Alternately, these negative results may be due to the exclusion of a large number of FH + women who had already experienced an episode of depression, resulting in the selection of a biased FH + sample who are resistant to the mood lowering effects of ATD.  相似文献   
999.
CONTEXT: Traumatic brain injury (TBI) is a principal cause of death and disability in young adults. Rehabilitation for TBI has not received the same level of scientific scrutiny for efficacy and cost-efficiency that is expected in other medical fields. OBJECTIVE: To evaluate the efficacy of inpatient cognitive rehabilitation for patients with TBI. DESIGN AND SETTING: Single-center, parallel-group, randomized trial conducted from January 1992 through February 1997 at a US military medical referral center. PATIENTS: One hundred twenty active-duty military personnel who had sustained a moderate-to-severe closed head injury, manifested by a Glasgow Coma Scale score of 13 or less, or posttraumatic amnesia lasting at least 24 hours, or focal cerebral contusion or hemorrhage on computed tomography or magnetic resonance imaging. INTERVENTIONS: Patients were randomly assigned to an intensive, standardized, 8-week, in-hospital cognitive rehabilitation program (n=67) or a limited home rehabilitation program with weekly telephone support from a psychiatric nurse (n=53). MAIN OUTCOME MEASURES: Return to gainful employment and fitness for military duty at 1-year follow-up, compared by intervention group. RESULTS: At 1-year follow-up, there was no significant difference between patients who had received the intensive in-hospital cognitive rehabilitation program vs the limited home rehabilitation program in return to employment (90% vs 94%, respectively; P=.51; difference, 4% [95% confidence interval ?CI?, -5% to 14%]) or fitness for duty (73% vs 66%, respectively; P=. 43; difference, 7% [95% CI, -10% to 24%]). There also were no significant differences in cognitive, behavioral, or quality-of-life measures. In a post-hoc subset analysis of patients who were unconscious for more than 1 hour (n = 75) following TBI, the in-hospital group had a greater return-to-duty rate (80% vs 58%; P=. 05). CONCLUSIONS: In this study, the overall benefit of in-hospital cognitive rehabilitation for patients with moderate-to-severe TBI was similar to that of home rehabilitation. These findings emphasize the importance of conducting randomized trials to evaluate TBI rehabilitation interventions. JAMA. 2000;283:3075-3081  相似文献   
1000.
We describe and discuss species of Plasmodium with four nuclei arranged in doublets or forming a maltese cross and loose, residual cytoplasm, described from Passer hispaniolensis in Algeria. The following species are described: Plasmodium rouxi from Alauda arvensis, from France Plasmodium mohammedi sp. nov. from Passer domesticus biblicus and Plasmodium pachysomum sp. nov. from Anthus campestris, from Israel, Plasmodium pfefferi sp. nov. from Pica pica and Plasmodium sergentorum sp. nov. from Alauda arvensis and Pica pica from France and Plasmodium stellatum sp. nov. from Muscicapa striata from Israel. All species vary in the spatial position of their four nuclei and the presence or absence of refractile, blue-staining globules. All of the described species differ from P. vaughani Novy et Mac Neal, 1904 and its siblings (example: P. vaughani merulae Corradetti et Scanga, 1973) in their number of merozoites (always four versus four to eight in the latter) and their spatial arrangement in the schizont.  相似文献   
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