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151.
Allergic rhinitis is the most common of the allergic diseases with, according to a number of epidemiological studies, an incidence of about 15% in Central Europe. The condition is characterized morphologically by inflammation of the nasal mucosa resulting from an IgE-mediated allergic reaction of the immediate type. Depending on the allergen involved and the course of the disease several forms of allergic rhinitis are distinguished. The present paper describes the pathophysiology and clinical symptomatology, current diagnostic approaches and the therapeutic possibilities with an eye to their practical relevance.  相似文献   
152.
Locomotor system has been studied in 24 patients with a history of Lyme's disease. All of them had arthralgia, 11 had relapsing arthritis, chronic arthritis occurred in 6 examinees. Arthritis presented as recurrent asymmetric mono-oligoarthritis affecting primarily joints of the lower limbs. Periarticular disorders were detected in 12 patients. Serologically, 18 of 24 patients had elevated titers of antibodies to Borrelia burgdorferi in indirect immunofluorescence test. Scintigraphy revealed polyarticular lesions in many cases, ultrasound investigation of the joints confirmed inflammatory nature of the pathological changes. It is inferred that combined methods of examination in diagnosis of Lyme's arthritis (titers to antibodies to Borrelia burgdorferi, ultrasound investigations, scintigraphy of the joints) provide most complete information.  相似文献   
153.
ProCys in the conserved sequence motif IV of [cytosine-C5]-DNA methyltransferases is known to be part of the catalytic site. The Cys residue is directly involved in forming a covalent bond with the C6 of the target cytosine. We have found that substitution of Pro-185 with either Ala or Ser resulted in a reduced rate of methyl group transfer by the EcoRII DNA methyltransferase. In addition, we observed an increase in the Km for substrate S-adenosyl-L-methionine (AdoMet), but a decrease in the Km for substrate DNA. This is reflected in minor changes in kcat/Km for DNA, but in 10- to 100-fold reductions in kcat/Km for AdoMet. This suggests that Pro-185 is important to properly orient the activated cytosine and AdoMet for methyl group transfer by direct interaction with AdoMet and indirectly via the Cys interaction with cytosine.  相似文献   
154.
Chemical prophylaxis is known to reduce the venographic prevalence of deep-vein thrombosis (DVT) after total knee replacement (TKR), but it is uncertain whether this affects the incidence of symptoms. Further analysis depends on the basic epidemiology of thromboembolic symptoms. We therefore studied the pattern of such symptoms in a consecutive series of 1000 patients with primary TKR, with particular reference to risk factors and prophylaxis. We reviewed all the clinical records and contacted all the patients individually, noting risk factors, prophylaxis, symptomatic pulmonary embolus (PE) or DVT and its timing, death and its causes, and all complications. All the patients wore antiembolism stockings, 83% had regional anaesthesia and 33.9% had chemical prophylaxis. One patient died from PE on the day of surgery, having had no prophylaxis giving a rate of 0.1% (95% CI 0.003% to 0.56%). Symptomatic, radiologically confirmed thromboembolism (VTE) was common with a rate of 10.6% (95% CI 8.7% to 12.5%). There was a similar incidence of VTE in those with and without chemical prophylaxis (10.1% v 10.5%, RR 0.96, NS). VTE was more common in patients with risk factors (15.1% v 9.5%, RR 1.59, p = 0.02) and tended to occur earlier in this group (median day of onset 5 v 7, p = 0.01). Chemical prophylaxis did not reduce the frequency of symptomatic thromboembolism in either those with risk factors (RR 0.81, p = 0.5) or those without them (RR 0.94, p = 0.8). Haematoma or wound dehiscence was more common in those having chemical prophylaxis (11.9% v 6.9%; RR 1.73 95% CI 1.16 to 2.60). Readmission for symptomatic, radio-logically confirmed thromboembolism involved 1.1% of patients (95% CI 0.55% to 2.1%). Four patients were readmitted with proven non-fatal PE and six with proven DVT (the latest on day 40). Our results show that the main risk factor for thromboembolism was TKR itself; chemical prophylaxis did not reduce the incidence of symptomatic thromboembolism but gave an increased perception of side-effects. New prophylactic methods or combinations of methods are needed, with their efficacy compared by randomised controlled studies of both the clinical and the radiological effect.  相似文献   
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The effect of Lamotrigine and carbamazepine on the development and character of the epileptiform seizures after strong sonic stimulation were studied on Krushinski?-Molodkina line of rats. Both drugs manifested a dose-dependent increase in the latency of motor reaction Lamotrigine administration in the dose range of 5-40 mg/kg, i.p., resulted in a moderate decrease in the seizure intensity preventing predominantly the tonic component of the seizure and failed to modify the character of convulsive reaction. Carbamazepine administered in doses of 7.5-30 mg/kg effectively prevented the epileptiform seizures. The "two-wave" motor reaction was observed in 15% of carbamazepine-treated rats.  相似文献   
158.
A nine-aperture, wide-field Fizeau imaging telescope has been built at the Lockheed-Martin Advanced Technology Center. The telescope consists of nine, 125 mm diameter collector telescopes coherently phased and combined to form a diffraction-limited image with a resolution that is consistent with the 610 mm diameter of the telescope. The phased field of view of the array is 1 murad. The measured rms wavefront error is 0.08 waves rms at 635 nm. The telescope is actively controlled to correct for tilt and phasing errors. The control sensing technique is the method known as phase diversity, which extracts wavefront information from a pair of focused and defocused images. The optical design of the telescope and typical performance results are described.  相似文献   
159.
The incidence of postoperative hypothyrosis after subtotal resection of the thyroid for diffuse toxic goiter is rather high, 40-50% according to many authors. A method is suggested permitting assessment of the share of "active zones" during surgery. A certain amount of thyroid tissue is left with due consideration for this share, this amount being sufficient to attain an euthyroid state in the postoperative period.  相似文献   
160.
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