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81.
82.
There are four species of Gymnetron in China recorded to date including Gymnetron
miyoshii Miyoshi, 1922, Gymnetron
villosipenne Roelofs, 1875, Gymnetron
auliense Reitter, 1907 and Gymnetron
vittipenne Marseul, 1876, of which the last two are new country records. The pre-imaginal stages including eggs, mature larvae and pupae of Gymnetron
miyoshii, Gymnetron
auliense and Gymnetron
vittipenne are described and illustrated. In addition, their diagnostic characters (larvae and pupae) are discussed and differentiated, and notes on some of their biological parameters are provided. Potential ecological impacts between Gymnetron weevils and their host Veronica spp. also are provided. 相似文献
83.
Data on the morphology of the egg, mature larva (L3) and pupa of Squamapion
elongatum (Germar, 1817) are presented. The development cycle of this species lasts 51–54 days: a 12-day egg period, a 30-day larval period, and a 12-day pupal period, on average. The larvae are attacked by parasitic hymenopterans of the superfamily Chalcidoidea. 相似文献
84.
Pei Chun Lai Yen Ta Huang Chia Chen Wu Ching-Jung Lai Pen Jung Wang Ted H Chiu 《Journal of biomedical science》2011,18(1):69
Background
Perinatal brain injury is the leading cause of subsequent neurological disability in both term and preterm baby. Glutamate excitotoxicity is one of the major factors involved in perinatal hypoxic-ischemic encephalopathy (HIE). Glutamate transporter GLT1, expressed mainly in mature astrocytes, is the major glutamate transporter in the brain. HIE induced excessive glutamate release which is not reuptaked by immature astrocytes may induce neuronal damage. Compounds, such as ceftriaxone, that enhance the expression of GLT1 may exert neuroprotective effect in HIE. 相似文献85.
86.
A pair of spherical unpigmented ocelli in addition to pigmented eyes have been observed in the anterior part of the prostomium in larvae of more than 40 species of Spionidae examined alive with light microscopy. Ocelli become visible in larvae at the one- to three-segment stage, increase in size as growth proceeds, and probably disintegrate in the course of metamorphosis because they were not observed in adults and settled juveniles. One pair of transparent, spherical bodies is also found in the anterior part of the head of planktotrophic pelagosphera larvae of Sipuncula. These bodies are in a similar position and have a similar appearance and size to unpigmented ocelli in Spionidae larvae. A pair of epidermal invaginations, densely covered with short cilia, is also observed antero-laterally in the head in pelagospheras of one species. These invaginations appear similar to the nuchal organs present in many polychaete larvae. Photoreceptive organs so far reported for sipunculan larvae comprise only pigmented eyes. Unpigmented ocelli and nuchal organs have never been reported in pelagospheras. Further ultrastructural investigations on sipunculan larvae are encouraged to clarify the composition, function and morphogenesis of transparent, spherical bodies and ciliated invaginations in the anterior part of the head. Such investigations may help to better understand the nature of photoreceptive structures and nuchal organs in Sipuncula, and also contribute to phylogenetic hypotheses regarding relationships of the Sipuncula and Annelida. 相似文献
87.
Raceková E Martoncíková M Mitrusková B Cízková D Orendácová J 《Cellular and molecular neurobiology》2005,25(7):1093-1105
Summary Accumulating evidence confirms that nitric oxide (NO), a versatile diffusible signaling molecule, contributes to controling
of adult neurogenesis. We have previously shown the timing of NADPH-diaphorase (NADPH-d) positivity within the rat rostral
migratory stream (RMS) during the first postnatal month. The present study was designed to describe further age-related changes
of NO presence in this neurogenic region. The presence of NO synthesizing cells in the RMS was shown by NADPH-d histochemistry
and neuronal nitric oxide synthase (nNOS) immunohistochemistry. The phenotypic identity of nitrergic cells was examined by
double labeling with GFAP and NeuN. Systematic qualitative and quantitative analysis of NADPH-d-positive cells was performed
in the neonatal (P14), adult(5 months) and aging (20 months) rat RMS.
1. Nitrergic cells with different distribution pattern and morphological characteristics were present in the RMS at all ages
examined. In neonatal animals, small, moderately stained NADPH-d-positive cells were identified in the RMS vertical arm and
in the RMS elbow. In adult and aging rats a few labeled cells could be also detected in the RMS horizontal arm. NADPH-d-positive
cells in adult and aging rats were characterized by long varicose processes and displayed dark labeling in comparison to the
neonatal group.
2. Double immunolabeling has revealed that nNOS-immunoreactivity co-localized with that of NeuN. This indicates that nitrergic
cells within the RMS are neurons.
3. Quantitative analysis showed that the number of NADPH-d-positive cells increases with advancing age.
The presence of NO producing cells in the RMS of neonatal adult and aging rats indicates, that this proliferating and migratory
area is under the influence of NO throughout the entire life of the animals. 相似文献
88.
Proteomic analysis of differential protein expression in response to epidermal growth factor in neonatal porcine pancreatic cell monolayers 总被引:3,自引:0,他引:3
Hong OK Suh SH Kwon HS Ko SH Choi YH Moon SD Yoo SJ Son HY Park KS Lee IK Yoon KH 《Journal of cellular biochemistry》2005,95(4):769-781
We have proposed that porcine neonatal pancreatic cell clusters (NPCCs) may be a useful alternative source of cells for islet transplantation, and that monolayer cultures might provide an opportunity to manipulate the cells before transplantation. In addition we previously identified 10 genes up-regulated by epidermal growth factor (EGF) in cultured porcine NPCC monolayers. We have now analyzed the intracellular signaling pathways activated by EGF and searched for proteins differentially expressed following EGF treatment of the monolayers, using two-dimensional gel electrophoresis (2-DE) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). EGF treatment resulted in phosphorylation of both Erk 1/2 and Akt, as well as increased cell proliferation. Five unknown and 13 previously identified proteins were differentially expressed in response to EGF. EGF treatment increased the expression of several structural proteins of epithelial cells, such as cytokeratin 19 and plakoglobin, whereas vimentin, the intermediate filament protein of mesenchymal cells, and non-muscle myosin alkali chain isoform 1, decreased. Heterogeneous nuclear ribonucleoprotein (hnRNP) A2/B1 factor, which promotes epithelial cell proliferation, and hemoglobin alpha I & II also increased, whereas cyclin A1, immunoglobulin heavy chain, apolipoprotein A1, 5,10-ethylenetetrahydrofolated reductase (5,10-MTHFR), angiotensin-converting enzyme 2 (ACE2), co-lipase II precursor, and NAD+ isocitrate dehydrogenase (NAD+ IDH) alpha chain proteins decreased. Our results show that EGF stimulates proliferation of pancreatic epithelial cells by simultaneously activating the MAPK and PI-3K pathways. HnRNP A2/B1, hemoglobin, cyclin A1, and ACE2 may play roles in the proliferation of epithelial cells in response to EGF. 相似文献
89.
Arboleda H Arboleda G 《Birth defects research. Part A, Clinical and molecular teratology》2005,73(8):562-568
BACKGROUND: Wiedemann-Rautenstrauch syndrome (WRS) characterizes a neonatal progeroid entity. In the last 30 years, 28 cases have been reported. In most cases of WRS, survival is short and long-term studies are impossible. CASE: In the present report, we describe a patient with WRS followed for 17 years at the Instituto de Genética, Universidad Nacional de Colombia; this is an exceptional survival period for a person with WRS. The information collected through 17 years for the present patient provides new knowledge about the natural evolution of this syndrome. New clinical and laboratory characteristics are compared with those reported for Rautenstrauch's patient "G." CONCLUSIONS: Our results confirm the variability of this syndrome, especially at the neurological level. However, many etiological and pathological aspects of this syndrome remain unknown. 相似文献
90.
The purpose of this paper is to document and interpret urban-rural differences in mortality in the past. To this end, we used data on mortality in Wielkopolska, Poland, in the 19th century and at the beginning of the 20th century. The data on mortality in rural areas (N = 1,173,910 deceased), small towns (N = 573,903 deceased), and Poznań, the capital of the Wielkopolska region (N = 86,352 deceased), were gathered from original Prussian statistical yearbooks (Preussische Statistik). Causes of death were also analyzed (rural areas, N = 449,576 deceased; small towns, N = 238,365 deceased; Poznań, N = 61,512 deceased). Mortality measures such as crude death rate (CDR), infant death rate (IDR), and neonatal and postneonatal death rates were calculated. Life tables were constructed for both stationary and stable population models and measures of the opportunity for natural selection calculated (Crow's index I(m), potential gross reproduction rate R(pot), and biological state index I(bs)). Relative frequencies of leading causes of death were computed. Stratification depending on the place of residence was evident in all mortality measures as well as in the values of the life tables and the measures of the opportunity for natural selection, but it was reverse of what is observed today in developed countries. In Poznań (a large industrial city), the mortality situation was the least favorable. It was caused by large population density, lack of water supply and sewage systems (up to 1896), and bad working conditions. The values of CDR ranged between 26.89-31.46, and IDR between 190.6-280.5. Newborn life expectancy (for a stable population model) was 31.6 years, I(m) = 0.79, R(pot) = 0.85, and I(bs) = 0.47. The most common causes of death were tuberculosis, other diseases of the respiratory and circulatory systems, dysentery and diarrhea, and cancer. These diseases were less common in rural areas, so they had the most favorable values of mortality measures (CDR between 22.87-27.32, IDR between 181.8-219.4, life expectancy of newborn e(0) = 42.12, I(m) = 0.55, R(pot) = 0.93, I(bs) = 0.60). Infectious diseases (other than tuberculosis), frailty at birth, and frailty in old age were the most frequent causes of death in rural areas. Small towns (population <20,000) had a mortality intermediate between city and rural areas. 相似文献