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991.
The diversity of cultured pathogenic bacteria in the bottled mineral water (BMW) was investigated using selective media. The pure isolates from these selective media, which showed hemolytic activity on the blood agar media and antibiotic resistance, were identified by 16S rRNA gene technique. The seven obtained strains were belonged to the genus Pseudomonas, Bacillus, Acinetobacter, Stenotrophomonas, and Exiguobacterium, and were mostly closed to the pathogenic strains. The increasing of ozone concentration from air-fed ozone generators eliminate the growth of bacteria included the pathogenic bacteria, but in other side it increases the amount of nitrates and nitrites in the final product of the BMW. These findings revealed that the BMW either has potential pathogenic bacteria or high levels of nitrates and all these products may effect on the health of the end user.  相似文献   
992.
993.
Although there is no specific therapy for gay male couples, this paper outlines the more critical issues therapists must understand to provide optimal treatment for gay male dyads. Additionally, the authors present new assumptions arising from their five year research study of 156 gay male couples living together from one to over 37 years. The most therapeutically useful finding is that stages of these relationships parallel stages of clinical development. Each stage has its own unique characteristics, stresses and benefits. Stages are affected by many influences, and individuals can be at different stages simultaneously.  相似文献   
994.
995.
Six asthmatic children were studied to determine whether supplemental, parenteral atropine would increase the effects of bronchodilation and protection against exercise-induced bronchoconstriction after maximal effects had been achieved by inhalation. First, we determined the amount of inhaled atropine sulfate that would give maximal bronchodilation for each patient at rest. This quantity of atropine was designated as "A." Then all subjects exercised for five sessions with the following pre-exercise treatments in a random order: (a) inhaled distilled water plus intramuscular (IM) saline solution; (b) inhaled A dose of atropine plus IM saline solution; (c) inhaled distilled water plus 0.35 mg IM atropine; (d) inhaled A dose of atropine plus 0.35 mg IM atropine; and (e) inhaled double the A dose plus IM saline solution. The results showed that the combination of inhaled and IM atropine had the greatest bronchodilation effect and the greatest protection against exercise-induced bronchoconstriction. Atropine inhalation alone (A dose) or IM injection (0.35 mg) was not as effective in bronchodilation or in alleviation of exercise-induced bronchoconstriction. Doubling the dose of inhalation (2A) did not increase the effects of the A dose. These results support the hypothesis that inhaled atropine does not reach all the airways where cholinergic receptors are present.  相似文献   
996.
Vitamin A can transform, in vitro, keratinized, multilayered, non secretory epithelium of carcinoma of portio cervicis into a simple mucous-secreting epithelium in the 40% of explants. The different response of Vit. A action on carcinoma may be associated with a different sensibility to this substance.  相似文献   
997.
998.
Amplification of a 340 bp sequence of the 38 kDa protein gene of Mycobacterium tuberculosis by the polymerase chain reaction has been developed. The sensitivity of this PCR was shown to be 10 fg both by agarose gel electrophoresis and Southern blot hybridisation being equivalent to 2-3 organisms and highly specific to M. tuberculosis and excluding even M. tuberculosis H37Ra and Mycobacterium bovis BCG. Sputum samples from patients with pulmonary tuberculosis gave a positivity rate of 45%. PCR was also performed using pt8 and pt9 primers which amplified a 541 bp sequence of IS6110. 41% of the above samples gave positive amplification. Three samples that were positive for 38 kDa sequence were negative for IS6110.  相似文献   
999.
Pretreatment of skin with all-trans retinoic acid (tretinoin) has been shown to enhance wound healing. Previous studies have mainly used animal models to demonstrate this effect. We wanted to determine whether pretreatment could promote wound healing in severely photoaged dorsal forearm skin. Four elderly men with severely actinically damaged forearms were treated daily for 16 weeks. One arm was treated with 0.05-0.1% tretinoin cream (Retin A, Ortho), and the other with Purpose cream (Ortho) as a vehicle control. Four-millimetre punch biopsies were taken from both dorsal forearms prior to treatment. After 16 weeks, full-thickness 2-mm punch biopsies were taken from both sides. Serial photographs were taken, and healing of the wounds quantitatively assessed by image analysis. On the 11th day, the wounds were excised using a 4-mm biopsy punch. Biopsies were processed for light microscopy. After 16 weeks, the tretinoin-treated forearms showed moderate erythema and scaling. Polarized light photographs revealed multiple, red, vascularized foci and/or a diffuse network of small vessels. The histological effects were typical for tretinoin, i.e. compaction of the stratum corneum, epidermal acanthosis with correction of atypia, an increase in small vessels, and increased cellularity in the upper dermis. Purpose cream had no effect, either clinically or histologically. On the tretinoin-treated side, the wound areas were 35-37% smaller on days 1 and 4, and 47-50% smaller on days 6, 8, 11, compared with the controls. Clinically and histologically, reepithelialization occurred more rapidly. Thus tretinoin dramatically accelerated wound healing in photodamaged skin.  相似文献   
1000.
Reversals in perceived direction of motion of a grating when its spatial frequency exceeds half that of the sampling mosaic provide a potential tool for estimating sampling frequency in peripheral retina. We used two-alternative forced-choice tasks to measure performance of three observers detecting or discriminating direction of motion of high contrast horizontal or vertical sinusoidal luminance gratings presented either 20 or 40 deg from the fovea along the horizontal meridian. A foveal target at a comfortable viewing distance aided fixation and accommodation. A Maxwellian view optometer with 3 mm artificial pupil was used to correct the refraction of the peripheral grating, which was presented in a circular patch, 1.8 deg in diameter, in a surround of similar colour and mean luminance (47.5 cd.m-2). The refractive correction at each eccentricity was measured by recording the aerial image of a point after a double pass through the eye. The highest frequency which can reliably be detected (7-14 c/deg at 20 deg, 5.5-7.5 c/deg at 40 deg) depends critically on refraction. Refraction differs by up to 5 D from the fovea to periphery, and by up to 6 D from horizontal to vertical. Direction discrimination performance shows no consistent reversals, and depends less on refraction. It falls to chance at frequencies as low as one-third of the highest that can be detected. Gratings which can be detected but whose direction of motion cannot be discriminated appear as irregular speckle patterns whose direction of motion varies from trial to trial.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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