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71.
72.
A comprehensive review of the outcomes associated with work-to-family conflict was conducted and effect sizes were estimated. Atypology was presented that grouped outcomes into 3 categories: work related, nonwork related, and stress related. Issues concerning the measurement of work-family conflict were also discussed. The results demonstrate the widespread and serious consequences associated with work-to-family conflict. On the basis of the results of the review, an agenda for future research was provided.  相似文献   
73.
This prospective, double blind study was undertaken to test the efficacy of intravenous "minipulse" (100 mg) methylprednisolone (MP) therapy versus standard pulse (1000 mg) MP therapy in rheumatoid arthritis (RA). Thirty-six patients with RA synovitis flares were randomized to receive either 100 or 1000 mg MP IV QD x 3 doses. These 2 universally comparable groups exhibited no statistically significant differences in their striking prompt and sustained clinical improvement. These data suggest that minipulse MP is as efficacious as conventional pulse MP in the treatment of RA flares.  相似文献   
74.
Starting in July 1985, the Gynecologic Oncology Group conducted a series of phase II trials with ifosfamide/mesna in advanced or recurrent gynecologic malignancies. Previously untreated patients received 1.5 g/m2 i.v. ifosfamide daily for 5 days. Mesna was given i.v. q4h×3 following ifosfamide; each dose was 20% of the daily ifosfamide dose. All patients with ovarian and 87% of those with cervical cancer had previously undergone platinum-based therapy. Because of the toxicity encountered in previously treated patients with ovarian carcinoma, the dose of ifosfamide was reduced to 1.2 g/m2 daily in all patients who had received prior chemo- or radiotherapy. In epithelial ovarian carcinoma, responses were observed in 8 (20.0%) of 41 evaluable patiens, with 3 (7.0%) complete responses. Response duration was 2.1–20.3+ months, with a median of 6.9+ months. In squamous-cell carcinoma of the cervix, 3 (11.1%) of 27 evaluable patients showed partial responses of 1.8, 2.2, and 3.1 months' duration. Of 26 untreated patients with mixed mesodermal tumors of the uterus, 5 (19.2%) achieved complete and 3 (11.5%) showed partial responses, for an overall response rate of 30.7%. Response duration was 1.4+-8.6 months, with a median of 3.8 months. Toxicity included two deaths due to renal insufficiency and a third related to neurologic impairment. Hematologic toxicity was manageable. Ifosfamide/mesna has activity in a wide range of gynecologic malignancies.Presented at the Satellite Symposium Ifosfamide in Gynecological Tumors of the 5th European Conference on Clinical Oncology and Cancer Nursing, London, September 3–7, 1989  相似文献   
75.
Potential sources of gaseous microemboli during cardiopulmonary bypass are varied. However, it is known that membrane oxygenators generate fewer gaseous microemboli than bubble oxygenators and that bubblers cannot utilize arterial heat exchange without generating significant gaseous microemboli during rewarming. A membrane oxygenator utilizing simultaneous gas and heat exchange raises the concern that concurrent gas and heat exchange would result in a higher production of gaseous microemboli compared to conventional venous heat exchange devices. This in vitro study compared venous, simultaneous, arterial and control (venous) heat exchanger gaseous microemboli counts during rewarming. No significant difference was found between the four heat exchangers when comparing inlet and outlet gaseous microemboli counts. This in vitro study suggests that there is no difference in gaseous microemboli generation when varying the position of the heat exchanger in the extracorporeal circuit incorporating a microporous membrane oxygenator.  相似文献   
76.
Subjective tinnitus is a common problem with many etiologies. Objective tinnitus, in which the sound is perceived by both the patient and the examiner, is less common. Objective tinnitus of the vascular type, in which a pulse synchronous bruit is heard by an independent observer, is frequently related to an underlying arterial or arteriovenous malformation, most commonly a dural arteriovenous fistula (DAVF) involving the transverse and sigmoid sinuses. The remaining cases are usually termed "essential" vascular tinnitus, and are presumed to have a venous etiology. In these cases, the audible noise is generally assumed to be produced within the sino-jugular connection, or within an enlarged jugular bulb. We present four documented cases of objective pulse synchronous tinnitus due to focal narrowing (acquired and developmental) of the mid-portion of the transverse dural sinus. In all cases, a bruit was audible directly over a focal constriction in the sinus, demonstrated by cerebral angiography or direct catheter venography. In one case, selective venography revealed a distensible sinus narrowing, associated with a jet of contrast marking fast flow within a developmental sinus segmentation. In another case, a loud pulse synchronous bruit was heard directly over a focal transverse sinus stenosis, which was detected by angiography at the site of a vascular surgical clip. In this case, magnetic resonance (MR) falsely predicted sinus occlusion. In two other cases, an audible bruit was also heard directly overlying a narrowed transverse sinus, seen in the venous phase of angiography. Transverse sinus stenosis is an unappreciated cause of objective pulsatile tinnitus, and we believe that this mechanism may underlie many cases of "essential" or venous etiology tinnitus not otherwise anatomically explained. Non-invasive testing, computed tomography (CT) and MR and non-directed angiography may overlook it. Conventional catheter arteriography or venography should be performed in such cases, with attention to the dural sinuses, if other tests fail to define the anatomic basis of the audible bruit.  相似文献   
77.
Automated activated clotting time (ACT) is utilized as the primary means of assessing anticoagulation status for cardiopulmonary bypass (CPB) procedures. Influences on the clotting cascade during CPB such as hypothermia, hemodilution, and platelet dysfunction are known to affect ACT. The recently introduced Thrombolytic Assessment System (TAS) has been reported to be less sensitive to changes in hemodilution and hypothermia during CPB than more conventional ACT devices. This study evaluated the ability of TAS, and two other commercially available automated ACT systems, the HemoTec and Hemochron, to correlate with circulating heparin levels. Reference standards for circulating heparin were determined by inactivation of factor Xa assay. Nineteen patients undergoing moderate hypothermic CPB served as subjects for this investigation. Blood samples were obtained for study at four time periods: 1) baseline (control), 2) post heparin administration (300-400 U/kg) prior to CPB, 3) during CPB, and 4) post protamine. Study results demonstrated a high correlation between the HemoTec and Hemochron (r = 0.99), increased heparin dose response on CPB compared to pre-CPB activity (p < 0.05), and a significant (p < 0.05) negative correlation between devices and patient hematocrit during CPB. Additionally, device correlation with anti-Xa assay during collection periods 2 and 3 showed negative correlations in each of the three devices evaluated. We conclude that all automated devices tested demonstrated an inability to predict circulating heparin at levels necessary for CPB, and that these discrepancies become magnified during CPB procedures.  相似文献   
78.
  • 1 Autoradiographic binding studies have shown that the AT1 receptor is the predominant angiotensin II (AngII) receptor subtype in the central nervous system (CNS). Major sites of AT1 receptors are the lamina terminalis, hypothalamic paraventricular nucleus, the lateral parabrachial nucleus, rostral and caudal ventrolateral medulla, nucleus of the solitary tract and the intermediolateral cell column of the thoraco-lumbar spinal cord.
  • 2 While there are differences between species, AT2 receptors are found mainly in the cerebellum, inferior olive and locus coeruleus of the rat.
  • 3 Circulating AngII acts on AT1 receptors in the subfornical organ and organum vasculosum of the lamina terminalis (OVLT) to stimulate neurons that may have a role in initiating water drinking.
  • 4 Centrally administered AngII may act on AT1 receptors in the median preoptic nucleus and elsewhere to induce drinking, sodium appetite, a sympathetic vasoconstrictor response and vasopressin secretion.
  • 5 Recent evidence shows that centrally administered AT1 antagonists inhibit dipsogenic, natriuretic, pressor and vasopressin secretory responses to intracerebroventricular infusion of hypertonic saline. This suggests that an angiotensinergic neural pathway has a role in osmoregulatory responses.
  • 6 Central angiotensinergic pathways which include neural inputs to the rostral ventrolateral medulla may use AT1 receptors and play a role in the function of sympathetic pathways maintaining arterial pressure.
  相似文献   
79.
The aim of this study was to compare the extent to which activity and immobility measures are related to sleep stages and sleep cycles in order to improve the informative value of actigraphic assessment of sleep. We therefore performed simultaneous ambulatory polysomnography and wrist-activity monitoring (AM) in 14 healthy male subjects without sleep complaints. In this context, a simple method for transforming raw motor activity data into a time-series reflecting onset and duration of activity and immobility clusters is introduced. Our results demonstrate that nocturnal AM measures were significantly affected by sleep stage. Low activity levels and particularly prolonged episodes of uninterrupted immobility were associated with increasing sleep depth. On the other hand, high activity levels and prolonged episodes of activity were related to intermittent wakefulness during sleep. Our results suggest that measures reflecting the occurrence and duration of activity and immobility clusters provide a better approach in studying the relationship between activity/immobility and sleep stages. Except for the duration of uninterrupted immobility episodes, which showed a significant decrease in the fourth cycle, none of the AM measures showed a significant cycle-to-cycle variation. Consequently, mean nocturnal motor activity measures provide an accurate reflection of the total sleep period. However, none of the AM-derived measures seems useful in evaluating the cycle structure during sleep.  相似文献   
80.
A review of the impact of computerized axial tomography on the radiological diagnosis of meningiomas is presented. Seventy-one intracranial and eight orbital cases have been examined by this new method using the 160 X 160 matrix. The diagnostic accuracy of the method is compared with established neuroradiological methods of examination (plain X rays, angiography, pneumography and isotope scanning). The new non-invasive method is undoubtedly the most accurate diagnostic tool yet available. It provided a specific diagnosis of meningioma in 77% of the intracranial cases without contrast enhancement and diagnosed the presence of tumour in a further 19% giving an overall tumour diagnosis of 96%. There were three false negatives (4%). After intravenous injection of contrast medium specific diagnosis of meningioma was made in a further six cases raising the specific diagnostic rate to 86%. Specific identification of intra-orbital meningiomas is more difficult though the presence of retro-orbital tumour was correctly diagnosed in all eight cases examined (100%). In none of our cases was a false positive diagnosis of tumour made. However, there are areas where a specific diagnosis of meningioma can only be made as part of a wider differential diagnosis. Apart from the orbit these include the suprasellar area, the cerebello-pontine angle, and the intraventricular regions. Occasionally also supratentorial gliomas or secondaries can simulate meningiomas.  相似文献   
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