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991.
Previous reports of the blood supply to the lenticular and long processes of the incus have failed to consider the potential contribution of the periosteal vascular plexus. This scanning electron microscopic study of vascular foramina on the cortical bone surface demonstrates that there is no statistical difference between the numbers of vascular foramina on the lenticular and long processes, as opposed to the body and short process. These results suggest that the blood supply to this portion of the ossicular chain may not be as tenuous as has been thought. 相似文献
992.
A remarkable nonlinearity has been observed for electric transport in K-TCNQ (potassium tetracyanoquinodimethane) quasi-one-dimensional
conductor. The negative differential resistance region appears afterV
m (turn over voltage), beyond which voltage goes down with increase of current. A possible mechanism is discussed in terms
of dynamics of charged solitons and domain walls in one-dimensional molecular stacks of these types of crystals. 相似文献
993.
P Kn?bl G Schernthaner C Schnack P Pietschmann A Griesmacher R Prager M Müller 《Canadian Metallurgical Quarterly》1993,36(10):1045-1050
Parameters of haemostasis, endothelial cell markers and lipid peroxide levels were studied in 64 Type 1 (insulin-dependent) and 94 Type 2 (non-insulin-dependent) diabetic patients according to their urinary albumin excretion rate in comparison with age-matched control subjects. We determined plasma levels of fibrinogen (Clauss' method), coagulation factor VII:activity (clotting assay), factor VII antigen, protein C and S antigen, von Willebrand factor antigen, D-dimer concentration (ELISA), and lipid peroxide levels (thiobarbituric acid) in relation to urinary albumin excretion rate (RIA). Significant positive correlations were found between urinary albumin excretion rate and plasma fibrinogen (p < 0.005, p < 0.02), factor VII activity (p < 0.0002, p < 0.002), factor VII antigen (p < 0.0001, p < 0.001), protein C (p < 0.003, p < 0.05), and lipid peroxides (p < 0.02, p < 0.004) in Type 1 as well as in Type 2 diabetes. Von Willebrand factor (p < 0.001) and protein S (p < 0.0005) correlated with albuminuria only in patients with Type 1 diabetes. Although most of the haemostatic abnormalities are already found in normoalbuminuric patients, the significant positive correlations to urinary albumin excretion indicate that endothelial cell damage and coagulation disorders deteriorate with the progression of diabetic nephropathy. 相似文献
994.
In order to precise the indications and results of this procedure, we assessed 11 cases of transformation of ileorectal anastomosis (IRA) to ileal pouch-anal anastomosis (IPAA) in ulcerative colitis (UC). These 5 men and 6 women had undergone IRA at a mean age of 31 years, 33 months after the diagnosis of UC (range 3-120). Four of these IRA, excluded by an ileostomy, had never been in function: the cause was severe persistent proctitis in 2 cases and anastomotic leakage and peritonitis in 2 cases. The other 7 IRA had been in function during a mean period of 25 months (range 6-45) and were reoperated because of anal sepsis (1 case), low rectal stenosis (1 case), disabling proctitis (4 cases) and rectal dysplasia (1 case). No patient had specific pathologic signs of Crohn's disease. The 11 IPAA were complicated by pelvic sepsis in 3 cases; surgical drainage succeeded in 1 case, but the 2 others needed pouch excision and terminal ileostomy. The diagnosis of Crohn's disease was eventually made in these 2 patients. The 9 patients with functioning IPAA, at a mean follow-up of 40 months (range 12-60), had 5.2 stools per 24 h (range 2-12), 5 patients had no nocturnal stooling, and 6 had a perfect continence. One patient had disabling chronic pouchitis. In conclusion, proctectomy with IPAA is always feasible when a previous IRA for UC had failed or offers poor results, but should be rejected in case of anal involvement, as that may suggest Crohn's disease. This procedure is followed by similar functional results than after primary IPAA. 相似文献
995.
996.
JW McAninch PR Carroll NA Armenakas P Lee 《Canadian Metallurgical Quarterly》1993,35(2):279-83; discussion 283-4
Over the past 14 years, 2079 patients have been seen at our institution with renal trauma. Of these, 84 sustained gunshot wounds (81 unilateral, 3 bilateral; a total of 87 renal units). We evaluated this group to characterize the nature of their injuries and establish a methodology for renal salvage and reconstruction. Preoperative radiographic staging was performed with excretory urography (IVP) or computed tomographic (CT) scanning. The injuries were classified into five categories: 16 contusions (18.4%), 12 minor lacerations (13.8%), 44 major lacerations (50.5%), six vascular injuries (6.9%), and nine combination laceration and vascular injury (10.3%). Most patients had multiple organ injuries, with 79 requiring associated surgical procedures (94%). The mean injury Severity Score (ISS) was 26.7 (range, 4-59). Based on radiographic and clinical staging criteria, 69 renal injuries were surgically explored (79.3%), and 12 patients underwent nephrectomy (13.8%). Forty-six renal units were reconstructed (66.6%) by various methods, including renorrhaphy, omental pedical flaps, mesh or peritoneal patch grafts, partial nephrectomy, and vascular repair. Overall, 75 renal units were salvaged (86.2%). Early renal vascular control was achieved in all patients who underwent renal exploration. Follow-up functional studies were done in 24 (28.5%): none had delayed nephrectomy or postinjury hypertension. Overall, 79 patients survived (94%); however, mortality was not related to renal injury. These findings suggest that aggressive radiographic staging coupled with early vascular control and careful selection of reconstructive techniques can ensure a high renal salvage rate in patients with renal gunshot injuries. 相似文献
997.
Paroxysmal atrial fibrillation is the most frequent of cardiac arrhythmias and its frequency increases with age. Its diagnosis is difficult since the symptoms are often absent or misleading. It is based on electrocardiogram performed during the attack, and this has been made easier by the Holter technique or by sequential recordings triggered by the patient himself. It is only in special cases, when percritical recordings could not be made that intracavitary electrophysiological study is used to obtain indirect arguments in favour of the diagnosis. All heart diseases can be attended by this cardiac rhythm disorder which usually marks an unfavourable turn in the course of the disease, with an increased risk of sudden death in the end. But in most cases the only disorder found is a common arterial hypertension. Atrial fibrillation carries a risk of peripheral, and in particular cerebral, embolism evaluated at 5% per annum. This risk is high in patients with cardiopathy, but it also exists even with a normal heart. The value of anticoagulants has been demonstrated by large controlled studies, but it is important to know that a very strong anticoagulant treatment is unnecessary to reduce the risk of embolism. Only antiarrhythmic agents can maintain the patients in sinus rhythm for as long as possible before the passage to permanent fibrillation. Although no beneficial effect on mortality has been proved, these drugs are indicated for patients who have very marked symptoms or a major cardiopathy.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
998.
999.
The status of single-case designs in counseling psychology is reviewed. Also, reasons for the underuse of these designs by counseling psychologists are discussed. Finally, potential contributions (1) in research linking process and outcome, (2) in group counseling, (3) across a variety of theoretical approaches, and (4) to evaluation and quality assurance in clinical practice are described. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
B López-Romero G Evrard F Durant M Sevrin P George 《Canadian Metallurgical Quarterly》1998,6(10):1745-1757
X-ray diffraction and ab initio MO theoretical calculations were used in order to investigate the structural and electronic properties of sarmazenil, a weak inverse agonist at the omega modulatory sites (benzodiazepine receptors). This compound was compared to bretazenil, a partial agonist, and to the antagonist flumazenil on the basis of structural and electronic data. The conformational and theoretical properties (interatomic pi overlap populations, molecular electrostatic potential (MEP), the topology of frontier orbitals, and proton affinity) of these three imidazobenzodiazepinones were determined in order to analyse the stereoelectronic properties in relation with their distinct intrinsic efficacies at the omega modulatory sites. 相似文献