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In central Italy, Prunus cerasus var. austera is cultivated as small stands or scattered trees in marginal areas for the production of jam and wine. Thanks to the healthy attributes of its products and its ability to grow in different environmental conditions, this variety has gained new interest in the development of marginal areas. We assessed the level of the genetic variability of P. cerasus var. austera germplasm from central Italy and identified a ‘core collection’ representative of the present genetic diversity. A total of 161 trees, morphologically identified as var. austera, and one tree, identified as var. caproniana were collected and genotyped by 14 SSRs. Two individuals provided by a commercial plant nursery, one of P. cerasus var. caproniana and one of P. cerasus var. austera, were used as control. Thirteen SSRs presented private alleles in austera. Seven individuals morphologically identified as austera revealed private alleles specific to caproniana. The PCoA and Bayesian clustering analysis showed a main genetic group including var. austera, while a second group included all the caproniana-like genotypes. A core collection of 31 trees (46% of austera genotypes) was selected. This study can be considered as a starting point for future investigations on this variety.  相似文献   
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We have examined the role of brain cortex phospholipids in regulating some enzymic reactions specific to the CNS. The study was carried out at the level of the reactions concerned with GABA formation, both in vivo and in vitro, and included investigation of the specificity of the effect. It was found that the brain cortex phospholipids enhance the transformation of exogenous vitamin B6 into pyridoxal-5-phosphate by activating the pyridoxal 5-phosphate-kinase enzyme, in contrast to other phospholipids of different origins. The possible role of brain cortex phospholipids in regulating an enzyme contained in the soluble fraction is discussed. Moreover, it is suggested that the specific effect of the phospholipids from various sources is linked to their fatty acid composition and to be therefore dependent on the aliphatic chains.  相似文献   
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Carotid intima-media thickness (cIMT) is a surrogate marker of early atherosclerotic changes in children. cIMT-studies are hard to compare, due to variations in ultrasound protocols, especially regarding the common carotid artery (CCA) segment measured in relation to the bulb. This study’s purpose was therefore to compare two distinct CCA segments in children, to see if cIMT values differ substantially according to the site of measurement. cIMT was assessed after power calculation in 30 children (15 girls) aged 8–17, using B-Mode ultrasound (5–13 MHz) at two CCA locations. The first measurement was performed over a distance of 1 cm immediately after the bulb (A), the second 1cm proximal the bulb (B) over the same distance of 1cm length. Means of end-diastolic far wall cIMT were compared between measurement A and B. cIMT in 30 participants was 0.51±0.06 mm for measurement A and 0.51±0.05 mm for measurement B. Results did not differ significantly (p = .947) over a distance of 2 cm after the bulb. According to our results, studies measuring CCA IMT within the first 2 cm, either close to the bulb or further proximal, can be compared. This will improve interpretation of data and application of reference values.  相似文献   
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To determine whether there is a short term increase in the risk of breast cancer after a full term birth data from two hospital based, case-control studies in Italy were pooled. Analysis was restricted to women aged under 50 with two or more children (573 women with cancer and 570 controls). A relative risk for breast cancer of 2.66 was seen in women who had given birth during the three years preceding the interview compared with women whose last birth had occurred 10 or more years before, after adjustment for age, age at first birth, and parity. The relative risk slowly decreased for women who had last given birth three to 10 years before. Multivariate analyses confirmed the protective effect of an early age at first birth and the age dependent effect of parity on the risk of breast cancer--that is, a direct relation below age 40 and an inverse one in older women. These data provide epidemiological evidence that a full term birth is followed by a transient increase in the risk of breast cancer, which for some time contrasts with and overcomes the long term protection of pregnancy at an early age. They therefore confirm predictions from animal studies and theoretical models that pregnancy prevents the early stages of breast carcinogenesis but promotes the late stages of the process.  相似文献   
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Many studies have established a correlation of differences in the activities of various muscle types with differences in the expression of myosin isoforms. In this paper we report the sequence determination of myosin light chain-2 from rabbit slow skeletal (LC2s) and ventricular (LC2v) nmscles. We sequenced tryptic peptides from LC2v which account for all except a few terminal amino acid residues. The major part (87 residues) of the rabbit LC2s sequence, obtained from tryptic and cyanogen bromide (CNBr) peptides, was found to be identical to rabbit LC2v. Our results provide the first sequence information on LC2s from any species, and lend strong support to the hypothesis that LC2s and LC2v are identical. Comparisons of rabbit LC2v and LC2s with rabbit LC2f (from fast skeletal muscle), and also with chicken LC2f and LC2v, show clearly that LC2s and LC2v from mammalian and avian species are more closely related to each other than they are to LC2f isoforms from the same species.  相似文献   
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Escherichia coli hemolysin is known to cause hemolysis of red blood cells by forming hydrophilic pores in their cell membrane. Hemolysin-induced pores have been directly visualized in model systems such as planar lipid membranes and unilamellar vesicles. However this hemolysin, like all the members of a related family of toxins called Repeat Toxins, is a potent leukotoxin. To investigate whether the formation of channels is involved also in its leukotoxic activity, we used patch-clamped human macrophages as targets. Indeed, when exposed to the hemolysin, these cells developed additional pores into their membrane. Such exogenous pores had properties very different from the endogenous channels already present in the cell membrane (primarily K+ channels), but very similar to the pores formed by the toxin in purely lipidic model membranes. Observed properties were: large single channel conductance, cation over anion selectivity but weak discrimination among different cations, quasilinear current-voltage characteristic and the existence of a flickering pre-open state of small conductance. The selectivity properties of the toxin channels appearing in phospholipid vesicles were also investigated, using a specially adapted polarization/depolarization assay, and were found to be completely consistent with that of the current fluctuations observed in excised macrophage patches. Received: 14 August 1995/Revised: 2 October 1995  相似文献   
9.
The expression of smooth muscle myosin light chain kinase (MLCK) was investigated during chicken gizzard development. The molecular weight and the antigenic properties of MLCK did not change during development. The use of anion exchange high performance liquid chromatography (HPLC) enabled us to distinguish between MLCKs from post-hatched and adult chickens. A partial amino acid sequence determination of 4-day-old gizzard MLCK failed to disclose differences in the primary sequences of the two proteins. The results suggest that MLCK has the same primary sequence in all sequences of the two proteins. The results suggest that MLCK has the same primary sequence in all stages of gizzard development, although charge variants due to post-translational modifications may exist.  相似文献   
10.
OBJECTIVES: To assess the potential of expectant management for simple ovarian cysts diagnosed by transabdominal or transvaginal ultrasonography. To compare the results of needle aspiration with those achieved with simple observation. DESIGN: Randomised trial. SETTING: Hospital department of obstetrics and gynaecology. SUBJECTS: 278 women with simple cysts randomly allocated to simple observation (143) or ultrasound guided fine needle aspiration (135) between 1990 and 1994. MAIN OUTCOME MEASURES: Resolution of cyst or development of malignancy. RESULTS: After six months 269 were available for follow up. The rate of resolution was 46% (59/128) with aspiration and 44.6% (63/141) with observation. Only the diameter of the cyst (P < 0.0001) was a significant independent prognostic factor for resolution in a multivariate analysis. Age and treatment had no significant effect. One woman was subsequently found to have borderline malignant changes on histopathological examination. Her cyst was detected by transabdominal ultrasonography. CONCLUSIONS: Expectant management for up to six months does not cause risks for the patients and allows spontaneous resolution in over a third of cases, avoiding the costs and risks of unnecessary surgery. Aspiration does not provide better results than simple observation.  相似文献   
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