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1.
Experiments were performed to determine the diurnal variation of, as well as the influence of total darkness on, tonic accommodation. In general, under both conditions trend analysis showed that variations in tonic accommodation over time were either nonsystematic in nature or could be best described by a simple linear function. Given the relatively small range of mean tonic accommodation values over time (0.5 to 1.1 D), the results demonstrate the robustness and stability of tonic accommodation under naturally occurring viewing conditions during the course of a day. In contrast, during the 2-hr period in total darkness, tonic accommodation exhibited a three-fold increase in mean range (0.6 to 2.5 D) as well as a significant increasing linear trend in some subjects, suggesting less stability of tonic accommodation in the absence of visual stimuli. 相似文献
2.
Saif S Rathore Andrew J Epstein Brahmajee K Nallamothu Harlan M Krumholz 《Journal of the American College of Cardiology》2006,47(7):1346-1349
A uniform policy for regionalization of ST-segment elevation myocardial infarction (STEMI) care raises several concerns. Transferring all STEMI patients to obtain primary percutaneous coronary intervention (PCI) may be less effective than transferring only high-risk STEMI patients. Delays in time to treatment >60 min associated with transferring patients for primary PCI may result in increased mortality for the average patient as compared with providing immediate fibrinolytic therapy at their initial hospital; yet more than 95% of patients transferred for primary PCI in the U.S. exceed this 60-min benchmark. Superior outcomes associated with treatment at higher-volume regional STEMI centers are inconsistent among centers, and there is no direct evidence that patients will benefit by a transfer to a high-volume hospital from a low-volume hospital. Published data suggest as many as 800 PCI patients would need to be transferred to a high-volume PCI hospital to avoid a single death at a low-volume PCI hospital. Although European randomized trial data suggest transferring patients with STEMI for primary PCI may be superior to immediate fibrinolytic therapy, these findings are unlikely to generalize to the U.S. health care system given size, geography, and organization. ST segment elevation myocardial infarction care regionalization would require a massive redistribution of health care resources, depriving several hospitals of advanced cardiac care facilities, expertise, and associated revenue. Clearer evidence of the benefits and discussion of potential harms are needed before adopting a national STEMI regionalization policy. 相似文献
3.
Balloon dacryocystoplasty: indications and contraindications 总被引:3,自引:0,他引:3
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6.
Nonepileptic Posttraumatic Seizures 总被引:4,自引:2,他引:2
Elizabeth Barry Allan Krumholz Gregory K. Bergey Herlene Chatha Shimellis Alemayehu Lynn Grattan 《Epilepsia》1998,39(4):427-431
Summary: Purpose: Epileptic posttraumatic seizures (PTSs) are a well-recognized consequence of head injury (HI), but HI and nonepileptic seizures (NESs) have not been related. We describe a significant subset of patients with NESs who had their seizures attributed to HI.
Methods: We reviewed the records of all patients diagnosed with NES at the University of Maryland Medical Center over a 6-year period (1989–1995) and selected patients with seizures attributed to a head injury occurring ≥3 years before the onset of their seizures.
Results: Of 157 patients with video-EEG confirmed NES, 37 (24%) had the onset of their seizures attributed to an HI. Their average age was 34 years (range, 15–56 years); 68% were women. Nonepileptic PTS usually developed within the first year after HI (89%). Convulsive symptoms were present in 54%. Whereas epileptic PTSs characteristically follow severe HI, the majority (78%) of our patients with nonepileptic PTSs sustained only mild HI. Before their HI, 76% of our patients were employed, working in the home, or students, but only 11% could continue those activities after developing nonepileptic PTSs.
Conclusions: Nonepileptic PTSs are frequently mistaken for epileptic PTSs and result in serious disability. The misdiagnosis of nonepileptic PTSs leads to ineffective and inappropriate treatment. Patients with intractable seizures after HIS, articularly mild HIS, should be carefully evaluated for NESs. 相似文献
Methods: We reviewed the records of all patients diagnosed with NES at the University of Maryland Medical Center over a 6-year period (1989–1995) and selected patients with seizures attributed to a head injury occurring ≥3 years before the onset of their seizures.
Results: Of 157 patients with video-EEG confirmed NES, 37 (24%) had the onset of their seizures attributed to an HI. Their average age was 34 years (range, 15–56 years); 68% were women. Nonepileptic PTS usually developed within the first year after HI (89%). Convulsive symptoms were present in 54%. Whereas epileptic PTSs characteristically follow severe HI, the majority (78%) of our patients with nonepileptic PTSs sustained only mild HI. Before their HI, 76% of our patients were employed, working in the home, or students, but only 11% could continue those activities after developing nonepileptic PTSs.
Conclusions: Nonepileptic PTSs are frequently mistaken for epileptic PTSs and result in serious disability. The misdiagnosis of nonepileptic PTSs leads to ineffective and inappropriate treatment. Patients with intractable seizures after HIS, articularly mild HIS, should be carefully evaluated for NESs. 相似文献
7.
Duncan WC; Illingworth PJ; Young FM; Fraser HM 《Human reproduction (Oxford, England)》1998,13(9):2532-2540
The molecular mechanisms involved in luteolysis are still unclear in the
primate. This study aimed to investigate the effect of induced luteolysis
on the ovarian luteinizing hormone (LH) receptor and the steroidogenic
enzyme, 3beta-hydroxysteroid dehydrogenase (3beta-HSD) in the marmoset
monkey. Luteolysis was induced in the mid-luteal phase either directly by
systemic prostaglandin F2alpha (PGF2alpha), or indirectly by LH withdrawal
using systemic gonadotrophin releasing hormone antagonist (GnRHant)
treatment. The LH receptor was studied by isotopic mRNA in-situ
hybridization and in-situ ligand binding and 3beta-HSD expression was
studied using isotopic mRNA in-situ hybridization and immunohistochemistry.
Induced luteolysis was associated with a reduction in the expression of LH
receptor (P < 0.0001) and 3beta-HSD mRNA, closely followed by a
reduction in the LH receptor (P < 0.05) and 3beta-HSD protein
concentrations within 24 h. There were no differences in the findings
whether luteolysis was induced with PGF2alpha or GnRHant. This study shows
that disparate mechanisms to induce luteolysis in the primate result in an
identical rapid loss of the LH receptor and 3beta-HSD. In conclusion,
induced luteolysis leads to rapid loss of the steroidogenic pathway in
luteal cells.
相似文献
8.
HM Clink 《Journal of clinical pathology》1980,33(8):799-800
9.
10.
Semen parameters and testicular pathology in men with testicular cancer and contralateral carcinoma in situ or bilateral testicular malignancies 总被引:2,自引:2,他引:2
Kliesch S; Bergmann M; Hertle L; Nieschlag E; Behre HM 《Human reproduction (Oxford, England)》1997,12(12):2830-2835
We evaluated 14 patients with bilateral testicular tumour, one-sided tumour
and contralateral carcinoma in situ (CIS) of the testis or testis tumour in
single testis with respect to their fertility. We analysed semen
parameters, serum hormones [follicle-stimulating hormone (FSH), luteinizing
hormone (LH) and testosterone], testicular sonography, testicular volumes
and testicular histology prior to further anti-cancer treatment. Ten out of
14 patients showed normal or reduced sperm concentrations, while 4/14
patients were azoospermic. Serum FSH levels showed a significant negative
correlation with sperm concentrations in patients with testicular
malignancies (r = -0.64, P = 0.025). Testicular volumes revealed a
significant positive correlation with semen parameters in patients with
testes that were affected by CIS (r = 0.733, P = 0.038). We conclude that
even bilateral testicular cancer and/or CIS do not preclude fertility and,
therefore, patients should be offered andrological investigation and
therapy, including possibly surveillance strategy or the chance for
cryopreservation of the semen prior to further treatment in order to
preserve their chances for paternity.
相似文献