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181.
Bekshaev AY 《Applied optics》2012,51(10):C13-C16
It is known that the orbital angular momentum of a paraxial light beam is related to the rotational features of the instantaneous optical-frequency oscillation pattern within the beam cross section [J. Opt. A 11, 094004 (2009)]. Now this conclusion is generalized: any identifiable directed motion of the instantaneous two-dimensional pattern of the field oscillations ("running" behavior of the instant oscillatory pattern) corresponds to the transverse energy flow in the experimentally observable time-averaged field. The transverse orbital flow density can be treated as a natural geometric and kinematic characteristic of this running behavior.  相似文献   
182.
The pistil of flowers is a specialized organ which contains the female gametophytes and provides the structures necessary for pollination and fertilization. Pollen deposited on the stigmatic surface of a compatible plant germinates a pollen tube which penetrates the stigmatic papillae and grows intercellularly through the style towards the ovules in the ovary. Pollen tube growth is largely restricted to the transmitting tissue in the style. Therefore the stylar transmitting tissue is extremely important for the migration of the pollen cell towards the ovary. We have isolated two related cDNAs, transmitting tissue-specific (TTS)-1 and TTS-2, derived from two proline-rich protein (PRP)-encoding mRNAs that accumulate specifically in the transmitting tissue of tobacco. The deduced PRP sequences share similarities with proline-rich cell wall glycoproteins found in a variety of plants. TTS-1 and TTS-2 mRNAs are induced in very young floral buds, accumulate most abundantly during the later stages of flower development when style elongation is the most rapid, and remain at relatively high levels at anthesis. These mRNAs become undetectable in maturing green fruits. In situ hybridization shows that TTS-1 and TTS-2 mRNA accumulation is restricted to the transmitting tissue of the style. The possible roles that these transmitting tissue-specific PRPs may play in maintaining the structural integrity of the style or in the function of this organ is discussed.  相似文献   
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Patients with essential hypertension complicated with left ventricular hypertrophy (LVH) confirmed by ultrasonic cardiography were divided randomly into observation group and control group. Both groups were treated with nifedipine. Shuizhi Tuyuan Powder (SZTYP, consisted of Hirudo nipponia and Eupolyphaga sinensis) was given in addition to the observation group. The therapeutic course for the two groups were 6 months. Results showed that after one course of treatment, the myocardial weight index lowered from 136.8 +/- 7.5 g/m2 to 130.5 +/- 6.4 g/m2 in observation group, while in control group, it lowered from 136.7 +/- 7.4 g/m2 to 134.3 +/- 6.2 g/m2, the difference between the two groups was significant (P < 0.01). The symptoms were relieved in part of the patients with early stage of cerebrovascular disease treated with SZTYP. The results suggested that SZTYP combined with nifedipine has active curative effect on essential hypertension patients complicated by LVH and part patients in early stage of cerebrovascular disease.  相似文献   
185.
The retinoblastoma gene (RB) is the prototypic tumor suppressor. Studies to date have demonstrated cancer suppression with tumor cells reconstituted with RB ex vivo and implanted into immunodeficient mice, as well as with germline transmission of a human RB transgene into tumor-prone Rb +/- mice. To mimic the therapy of cancer more closely, spontaneous pituitary melanotroph tumors arising in immunocompetent Rb +/- mice were treated with a recombinant adenovirus carrying RB cDNA. Intratumoral RB gene transfer decreased tumor cell proliferation, reestablished innervation by growth-regulatory dopaminergic neurons, inhibited the growth of tumors, and prolonged the life spans of treated animals.  相似文献   
186.
Site-directed mutagenesis was used to investigate the loading of iron into rat liver ferritin by ceruloplasmin. Changes were made in the H chain to investigate the role of tyrosines involved in an inherent ferroxidase activity thought to be involved in the self-loading of iron into ferritin. Mutation Y34F affected the rate of iron loading by ceruloplasmin and incorporation of the oxidized iron into the core. Mutation Y29R (making it analogous to the L chain) had no effect on iron oxidation but slightly decreased core formation. A double mutation in the L chain, to open the alpha-helix bundle channel, and R25Y, making the protein more analogous to the H chain, increased the amount of iron incorporated into the core, again suggesting that this Tyr is involved in ligand exchange for core formation. Additional changes in the L chain involving the BC loop suggest that the entire BC loop is involved in the association of ferritin with ceruloplasmin, increasing its ferroxidase activity and the rate of iron loading into ferritin.  相似文献   
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Late-onset schizophrenia (LOS) is likely a syndrome of diverse etiology. In a series of related studies, we compared LOS patients with normal controls, elderly patients with early-onset schizophrenia (EOS), and Alzheimer's disease patients, using magnetic resonance imaging (MRI) and neuroreceptor positron emission tomography measures, which had previously been reported to be abnormal in EOS. EOS and LOS patients showed similar MRI changes. LOS drug-naive patients had elevated Bmax (receptor density) values for dopamine D2 receptors compared with age and gender norms, a phenomenon previously reported by our group in young schizophrenia patients.  相似文献   
189.
A multicentre, randomized, double-blind, controlled crossover clinical trial was conducted on 33 patients with severe refractory atopic dermatitis, to determine the effects of cyclosporin (5 mg/kg/day) on their health-related quality of life. Treatments were administered for 8-week periods. One group (n = 16) received placebo followed by cyclosporin, and the other (n = 17) received cyclosporin and then placebo. Health-related quality of life was assessed at 0, 8 and 16 weeks using a general measure, the United Kingdom Sickness Impact Profile (UKSIP), an eczema-specific measure, the Eczema Disability Index (EDI), and a global 5-point rating scale of overall health (very good to very poor). In addition, clinical assessments (i.e. extent and activity of disease) were made by the investigators. UKSIP and EDI scores indicated significant improvement in quality of life (P < 0.05-P < 0.01) of patients with atopic dermatitis after treatment with cyclosporin. Although no patient required withdrawal from the study, 20 patients receiving cyclosporin reported adverse events, compared with eight taking placebo. There was a close correlation (P < 0.05-P < 0.01) between the UKSIP and EDI scores. In contrast, there was either no correlation, or only a very poor correlation, between the quality of life parameters and clinical measures of extent and activity of eczema. When cyclosporin was stopped, relapse was rapid, but the mean scores for disease activity and extent of disease were less than their baseline values (i.e. an improvement of greater than 25% was maintained in 11 patients at week 4).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
190.
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