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11.
Gerald Westheimer 《Optometry and vision science》2003,80(11):745-748
When the contrast polarity of a visual acuity chart is reversed by using bright letters on a dark background instead of dark on light, the shape and height of the resolution feature in the retinal image is identical but inverted compared with the normal situation. However, the contrast is different in the two cases because the background light level, which is a dividing factor when contrast is calculated, is much less when only the letters are bright. To the extent that contrast is a limiting factor in visual acuity, reversed-contrast acuity would be expected to be better, and proportionally more so in eyes where light scatter and aberrations widen and flatten the point-spread function. In a careful psychophysical study of Landolt C resolution, the minimum angle of resolution was found to be significantly smaller for white letters on a dark background than for the traditional dark on bright situation. 相似文献
12.
13.
Gerald Klose 《Medizinische Klinik》2005,2(4):99-106
Eine 71-jährige, gesundheitsbewusste, zu einer Medizinerfamilie gehörige Patientin stellt sich zur Bewertung einer seit 10 Jahren bekannten Cholesterinerhöhung und der an anderer Stelle begonnenen Behandlung mit Mevinacor® (Lovastatin) vor.Im vorausgegangenen Jahr waren bei vielen Gelegenheiten Gesamtcholesterinkonzentrationen zwischen 289 und 345 mg/dl bestimmt worden. LDL wurde bis auf maximal 261 mg/dl erhöht gefunden, die HDL-Cholesterin-Werte lagen zwischen 40 und 48 mg/dl, die Triglyzeride zwischen 99 und 264 mg/dl. 相似文献
14.
Gerald A. Beathard 《Seminars in dialysis》1995,8(4):241-242
A substantial fraction of clotted polytetrafluoroethylene (PTFE) grafts undergoing thrombolysis and angioplasty clot again within a few months. Is there a place for routine follow-up fistulograms in these patients, or should we just retreat them as needed? Is there, perhaps, a subgroup that requires special management? 相似文献
15.
Symptomatic and Clinical Improvement in Morbidly Obese Patients with Gastroesophageal Reflux Disease Following Roux-en-Y Gastric Bypass 总被引:3,自引:0,他引:3
Background: Patients who suffer with gastroesophageal reflux Disease (GERD) endure a worsening of symptoms as their weight
increases. When medical treatment of this condition in the morbidly obese patients fails, surgical intervention may be indicated.
Choosing a procedure which not only helps achieve weight control but which also relieves symptoms and complications of GERD
is the goal. We present a review of patients who have undergone Roux-en-Y Gastric Bypass (RYGBP) and related procedures for
this disease. Methods: One hundred eighty-eight patients undergoing surgery for morbid obesity and for GERD in 1992-1996 were
contacted by mail or phone. All of these patients had undergone preoperative esophagogastroduodenoscopy to grade the severity
of their disease. Their preoperative symptoms were compared to those experienced postoperatively. Results: One hundred thirty
patients underwent a RYGBP with modified Hill fundopexy, 22 patients underwent a distal gastrectomy with modified Hill fundopexy,
8 patients underwent distal gastrectomy alone and 28 patients underwent RYGBP alone. There have been no deaths. There were
nine surgical complications, eight early and one at 2.5 years postoperation. Follow-up is 4-48 months. The average BMI dropped
from 43 to 30.2 kg/m2. Whereas all patients were on some form of medical therapy before surgery, only 14 reported the need for medication postoperatively.
Conclusions: Surgical intervention for weight control and treatment of GERD has been highly successful in our experience both
with respect to weight control and to the reduction of reflux symptoms. Depending upon endoscopic and operative findings a
RYGBP with or without an antireflux procedure can provide dramatic improvement. Gastrectomy with antireflux modifications
is appropriate in selected cases. 相似文献
16.
17.
Rolf W. Hartmann Martin Frotscher Dorothea Ledergerber Gerald A. Wchter Gertrud L. Grün Tom F. Sergejew 《Archiv der Pharmazie》1996,329(5):251-261
In search of potential drugs for the treatment of estrogen- and androgen-dependent cancer as well as the prophylaxis of metastases, tetralones, tetralins, and dihydronaphthalenes bearing a OCH3 substituent at the benzene nucleus and an imidazol-4-yl, imidazol-1-yl, or 1,2,4-triazol-1-yl substituent in 2-position were synthesized with and without C1-spacer between the rings (compounds 2 – 26 ). The compounds were tested in vitro for inhibition of the three target enzymes P450 arom (human placental microsomes), P450 17 (rat testicular microsomes), and P450 TxA2 (citrated human whole blood). To examine selectivity, some compounds were further tested in vitro for inhibition of P450 18 (bovine adrenal mitochondria), P450 see (bovine adrenal mitochondria) and corticoid formation (aldosterone, corticosterone; ACTH stimulated rat adrenal tissue). In vivo, selected compounds were examined in Sprague Dawley rats regarding P450 TxA2 inhibition, reduction of plasma testosterone concentration, antiuterotrophic activity (inhibition of the uterotrophic activity of androstenedione), reduction of plasma estradiol concentration (pregnant mares' serum gonadotropin-primed rats), and mammary tumor inhibiting activity (dimethylbenzanthracene-induced tumor; pre- and postmenopausal model). In the series of imidazol-4-yl compounds, which represent a novelty in the field of azole inhibitors of steroidogenic P450 enzymes, strong inhibitors of P450 arom and/or P450 17 were found: 7-OCH3-2-(imidazol-4-ylmethylene)-1-tetralone ( 4 ) and 7-OCH3-2-(imidazol-4-ylmethyl)-tetralin ( 12 ) are among the most potent inhibitors of P450 arom in vitro known so far. Compound 4 is a selective inhibitor, whereas 12 shows in addition strong inhibition of P450 17. In contrast to 12 , the 6-OCH3 derivative (compound 11 ) is a selective inhibitor of P450 17, being 50 times more potent than ketoconazole. Some imidazol-1-yl compounds show a marked inhibition of P450 TxA2: 2-(imidazol-1-ylmethyl)-1-tetralone ( 13 ) is a selective inhibitor of P450 TxA2, whereas 7-OCH3-2-(imidazol-1-ylmethyl)-tetralin ( 17 ) as well as 2-(imidazol-1-ylmethyl)-tetralin ( 16 ) and 7-OCH3-2-imidazol-1-yl-3,4-dihydronaphthalene ( 25 ) additionally show strong inhibition of P450 arom and P450 17. Regarding the other steroidogenic P450 enzymes as well as corticosterone formation, the compounds show only little inhibitory activity. Aldosterone formation, however, is inhibited at low concentrations. Nevertheless, 4 and 12 are more selective, i.e. inhibit aldosterone synthesis less than the well known inhibitor of P450 arom fadrozole. The compounds show activity in the aforementioned in vivo tests. 相似文献
18.
Gerald F. Powell MD Barbara A. Bettes PhD 《Child psychiatry and human development》1992,22(3):185-198
A controversy exists regarding the classification of nonorganic failure to thrive within the psychiatric nomenclature. There are a number of DSM-III-R diagnoses that may be applied to NOFTT, including Reactive Attachment Disorder of Infancy (RADI) and Major Depressive Disorder (MDD). The behaviors characteristic of NOFTT are symptomatic of depression, and are similar to those exhibited by infants with anaclitic depression as well as those of the adult with depression. The correspondence of the behaviours of NOFTT and the DSM-III-R criteria for Major Depression are reviewed, as are the conceptual and therapeutic reasons to view NOFTT infants as suffering from Depression. 相似文献
19.
20.
Gerald Gabriel 《医疗保健器具》2007,(10):36-37
IQ的缺点关于智力的理解,有没有一致的意见呢?智商即"IQ"并不全部的说明一个人在世界的成功或者失败。事实上,大部分的研究智力的社会学家估计智商只说明了20%~30%的成果。即使支持者断言说,智商是"最著名的预报值",例如金融投资的成功,但这些数值不是你可以打赌的。 相似文献