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81.
Djurić MP Roberts CA Rakocević ZB Djonić DD Lesić AR 《American journal of physical anthropology》2006,130(2):167-178
Bone fractures were analyzed from skeletal remains of 861 adult individuals from six cemeteries dating to the Late Medieval period in Serbia. Results of the study were compared to other cemetery populations (635 individual skeletons) of the same date and region in an attempt to understand fracture patterns. The association of types of fractures and their prevalence with sex, age at death, cemetery site, and information deriving from historical sources are discussed. Results showed that the long bone fracture frequency was 0.7%, and the majority of the fractures were the result of direct force. This rate is similar to some studies of contemporary British skeletal samples. However, it is much lower than for some other Old World sites. Cranial vault fractures had a rate of 6.7%, and of the facial skeleton, 1.3%; the frontal bone was the most affected of bones of the cranial vault. Injuries were more common on the upper extremities (0.8%) compared to the lower (0.6%). However, the fibula was the most fractured bone (2.8%), followed by the ulna (2.4%). This pattern is similar to three of six Late Medieval urban sites in Britain. These findings suggest that this rural community was exposed to a low risk of trauma, probably related mostly to accidents sustained during farming, and rarely to interpersonal violence. 相似文献
82.
Anita Ljubičić Ćalušić Mladinić MarinVarnai Veda Marija Petrinec BrankoMacan Jelena Kopjar NevenkaLucić Vrdoljak Ana Želježić Davor 《Journal of thermal biology》2012
Flashover phenomenon occurs when surfaces exposed to thermal radiation reach the ignition temperature, and the fire rapidly spreads in enclosed area. Flashover training (FOT) performed by firefighters is a simulation of flashover phenomenon under controlled conditions. The study aimed to test thermal and physical strain in male firefighters and instructors attending FOT and its influence on DNA damage, exhaled breath condensate (EBC) pH, and fraction of exhaled nitric oxide (FeNO). DNA damage markers were analyzed in 51 attendees and 7 instructors, and EBC pH and FeNO in 40 respiratory healthy non-smoking subjects (34 attendees and 6 instructors).The average body temperature and pulse increase was 1.1 °C and 30 beats per minute, respectively. A prominent increase in the alkali-labile sites' level has been observed in instructors' peripheral leukocytes compared to first-time attendees (tail length p=0.050, % of DNA in tail p=0.005). FOT was related only to physiological FVC and FEV1 increase (by 4% and 2.7% on average), and FeNO dropped after the exercise by 2 ppb in comparison with basal values (P=0.034). EBC pH did not change during FOT, but FeNO was inversely correlated to EBC pH after the exercise (Spearman's rho=−0.66, P=0.013). With respect to the thermal and physical strain, FOT is considered to be a safe training procedure for healthy firefighters. The increase rate in primary DNA damage found in the instructors' peripheral leukocytes requires further examination in a larger sample size. 相似文献
83.
Bubas M Milosević M Delić-Brkljacić D Zahariev-Vuksinić K 《Collegium antropologicum》2012,36(2):585-592
The variability that exists within the populations of individual countries and the variability that exists between the populations of different countries are both of interest in practical application. For these reasons, a comparison is made in this work between certain anthropometric variables of our sample of Croatian population and anthropometric variables that are available for other human populations in the world of the same or a similar age. The total sample was 1,372 subjects aged from 23 to 59 years old. For the purpose of comparison, data were taken from the study "International Data on Anthropometry" which provides an overview of anthropometric variables for many world populations, as well as data from Rudan's research that was carried out on Croatian population in the late seventies of the last century. Mean value, standard deviation and coefficient of variation have been calculated for every measured parameter. A comparison between the two research samples of Croatian population fairly displays up going trend, for body mass and other bodily dimensions, formed in three decades of difference. Mean value for body height in Rudan's sample is 161.0 cm, and for Bubas's sample in this research was 170.6 cm, both values state for Croatian population but with difference of more than 30 years. Human biologists use term "secular trend" to describe alterations in the measurable characteristics of a population of humans that occur over a century. Accordingly, in adult age, the rate of gain, concerning body height, is 10 to 30 mm per decade. The changes in body proportions during recent decades are less marked than those in body size, but the relationships between stature and weight within one national group have changed significantly. 相似文献
84.
During the eighteen-year period in "Sestre milosrdnice" University Hospital Center, Zagreb, 271 women with ovarian tumor was studied. 229 women with ovarian cancer and 42 with borderline tumor. The pathohistological types of tumors were different. The age of the patients ranged from 20-83 years. In all patients the value of biochemical marker CA125 was determined. The aim of this study was to determine the usefulness of CA125 measurement in different age groups and in different patohistologycal forms of tumor. CA125 has proven to be positive in 89.1% of women with ovarian cancer and in 62% with neoplasm of low malignant potential. The higher values of CA125 were detected in younger women with low malignant tumor potential. Serous and metastatic tumor types were also associated with higher values of CA125. 相似文献
85.
86.
Schiavinato A Becker AK Zanetti M Corallo D Milanetto M Bizzotto D Bressan G Guljelmovic M Paulsson M Wagener R Braghetta P Bonaldo P 《The Journal of biological chemistry》2012,287(14):11498-11515
EMILIN-3 is a glycoprotein of the extracellular matrix belonging to a family that contains a characteristic N-terminal cysteine-rich EMI domain. Currently, EMILIN-3 is the least characterized member of the elastin microfibril interface-located protein (EMILIN)/Multimerin family. Using RNA, immunohistochemical, and protein chemistry approaches, we carried out a detailed characterization of the expression and biochemical properties of EMILIN-3 in mouse. During embryonic and postnatal development, EMILIN-3 showed a peculiar and dynamic pattern of gene expression and protein distribution. EMILIN-3 mRNA was first detected at E8.5-E9.5 in the tail bud and in the primitive gut, and at later stages it became abundant in the developing gonads and osteogenic mesenchyme. Interestingly and in contrast to other EMILIN/Multimerin genes, EMILIN-3 was not found in the cardiovascular system. Despite the absence of the globular C1q domain, immunoprecipitation and Western blot analyses demonstrated that EMILIN-3 forms disulfide-bonded homotrimers and higher order oligomers. Circular dichroism spectroscopy indicated that the most C-terminal part of EMILIN-3 has a substantial α-helical content and forms coiled coil structures involved in EMILIN-3 homo-oligomerization. Transfection experiments with recombinant constructs showed that the EMI domain contributes to the higher order self-assembly but was dispensable for homotrimer formation. EMILIN-3 was found to bind heparin with high affinity, a property mediated by the EMI domain, thus revealing a new function for this domain that may contribute to the interaction of EMILIN-3 with other extracellular matrix and/or cell surface molecules. Finally, in vitro experiments showed that EMILIN-3 is able to function as an extracellular regulator of the activity of TGF-β ligands. 相似文献
87.
Subczynski WK Raguz M Widomska J Mainali L Konovalov A 《The Journal of membrane biology》2012,245(1):51-68
The most unique feature of the eye lens fiber-cell plasma membrane is its extremely high cholesterol content. Cholesterol
saturates the bulk phospholipid bilayer and induces formation of immiscible cholesterol bilayer domains (CBDs) within the
membrane. Our results (based on EPR spin-labeling experiments with lens-lipid membranes), along with a literature search,
have allowed us to identify the significant functions of cholesterol specific to the fiber-cell plasma membrane, which are
manifest through cholesterol–membrane interactions. The crucial role is played by the CBD. The presence of the CBD ensures
that the surrounding phospholipid bilayer is saturated with cholesterol. The saturating cholesterol content in fiber-cell
membranes keeps the bulk physical properties of lens-lipid membranes consistent and independent of changes in phospholipid
composition. Thus, the CBD helps to maintain lens-membrane homeostasis when the membrane phospholipid composition changes
significantly. The CBD raises the barrier for oxygen transport across the fiber-cell membrane, which should help to maintain
a low oxygen concentration in the lens interior. It is hypothesized that the appearance of the CBD in the fiber-cell membrane
is controlled by the phospholipid composition of the membrane. Saturation with cholesterol smoothes the phospholipid-bilayer
surface, which should decrease light scattering and help to maintain lens transparency. Other functions of cholesterol include
formation of hydrophobic and rigidity barriers across the bulk phospholipid-cholesterol domain and formation of hydrophobic
channels in the central region of the membrane for transport of small, nonpolar molecules parallel to the membrane surface.
In this review, we provide data supporting these hypotheses. 相似文献
88.
Tep S Mihaila R Freeman A Pickering V Huyhn F Tadin-Strapps M Stracks A Hubbard B Caldwell J Flanagan WM Kuklin NA Ason B 《Journal of lipid research》2012,53(5):859-867
Microsomal triglyceride transfer protein (Mtp) inhibitors represent a novel therapeutic approach to lower circulating LDL cholesterol, although therapeutic development has been hindered by the observed increase in hepatic triglycerides and liver steatosis following treatment. Here, we used small interfering RNAs (siRNA) targeting Mtp to achieve target-specific silencing to study this phenomenon and to determine to what extent liver steatosis is induced by changes in Mtp expression. We observed that Mtp silencing led to a decrease in many genes involved in hepatic triglyceride synthesis. Given the role of diacylglycerol O-acyltransferase 2 (Dgat2) in regulating hepatic triglyceride synthesis, we then evaluated whether target-specific silencing of both Dgat2 and Mtp were sufficient to attenuate Mtp silencing-induced liver steatosis. We showed that the simultaneous inhibition of Dgat2 and Mtp led to a decrease in plasma cholesterol and a reduction in the accumulation of hepatic triglycerides caused by the inhibition of Mtp. Collectively, these findings provide a proof-of-principle for a triglyceride synthesis/Mtp inhibitor combination and represent a potentially novel approach for therapeutic development in which targeting multiple pathways can achieve the desired response. 相似文献
89.
Maja Milo?evi? Snje?ana Petrovi? Nata?a Veli?kovi? Ivana Grkovi? Marija Ignjatovi? Anica Horvat 《Molecular and cellular biochemistry》2012,371(1-2):199-208
Extracellular nucleotides affect female reproductive functions, fertilization, and pregnancy. The aim of this study was to investigate biochemical characteristics of ATP and ADP hydrolysis and identify E-NTPDases in myometrial cell membranes from Wistar albino rats. The apparent K m values were 506.4?±?62.1 and 638.8?±?31.3?μM, with a calculated V max (app) of 3,973.0?±?279.5 and 2,853.9?±?79.8?nmol/min/mg for ATP and ADP, respectively. The enzyme activity described here has common properties characteristic for NTPDases: divalent cation dependence; alkaline pH optimum for both substrates, insensitivity to some of classical ATPase inhibitors (ouabain, oligomycine, theophylline, levamisole) and significant inhibition by suramine and high concentration of sodium azides (5?mM). According to similar apparent Km values for both substrates, the ATP/ADP hydrolysis ratio, and Chevillard competition plot, NTPDase1 is dominant ATP/ADP hydrolyzing enzyme in myometrial cell membranes. RT-PCR analysis revealed expression of three members of ectonucleoside triphosphate diphosphohydrolase family (NTPDase 1, 2, and 8) in rat uterus. These findings may further elucidate the role of NTPDases and ATP in reproductive physiology. 相似文献
90.
EPR spin-labeling methods were used to investigate the order and fluidity of alkyl chains, the hydrophobicity of the membrane
interior, and the order and motion of cholesterol molecules in coexisting phases and domains, or in a single phase of fluid-phase
cholesterol/egg-sphingomyelin (Chol/ESM) membranes with a Chol/ESM mixing ratio from 0 to 3. A complete set of profiles for
these properties was obtained for the liquid-disordered (l
d) phase without cholesterol, for the liquid-ordered (l
o) phase for the entire region of cholesterol solubility in this phase (from 33 to 66 mol%), and for the l
o-phase domain that coexists with the cholesterol bilayer domain (CBD). Alkyl chains in the l
o phase are more ordered than in the l
d pure ESM membrane. However, fluidity in the membrane center is greater. Also, the profile of hydrophobicity changed from
a bell to a rectangular shape. These differences are enhanced when the cholesterol content of the l
o phase is increased from 33 to 66 mol%, with clear brake-points between the C9 and C10 positions (approximately where the
steroid-ring structure of cholesterol reaches into the membrane). The organization and motion of cholesterol molecules in
the CBD are similar to those in the l
o-phase domain that coexists with the CBD. 相似文献