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1.
E. Backe G. Lotz U. Tittelbach H. Thurmer E. Gierke N. Kersten A. Bernard G. Wallenstein W. D. Schneider 《Biomarkers》2000,5(2):119-128
The inflammation markers alpha-1-antitrypsin (AAT), Clara cell protein (CC-16), soluble interleukin-2-receptor (IL-R) and the soluble adhesion molecule E-selectin, the intercellular adhesion molecule (ICAM-1) and the vascular adhesion molecule (VCAM-1) were determined in the serum of 195 salt-exposed miners to analyse dose-response relationships between markers and potash dust. Alpha-1-antitrypsin, Clara-cell protein, IL2-R, E-selectin and VCAM-1 were not changed by salt exposure, however the ICAM-1 level in the serum fell slightly as the salt exposure increased. This effect was strongest in the group of smokers, still visible in the group of ex-smokers, no effect was seen in non-smokers. Markers, with the exception of VCAM-1, were influenced by tobacco exposure. Since markers were not elevated in relation to salt dust exposure, the results do not support an inflammatory effect of potash dust on the respiratory system. 相似文献
2.
Cytokine regulation of facilitated glucose transport in human articular chondrocytes. 总被引:10,自引:0,他引:10
A R Shikhman D C Brinson J Valbracht M K Lotz 《Journal of immunology (Baltimore, Md. : 1950)》2001,167(12):7001-7008
Glucose serves as the major energy substrate and the main precursor for the synthesis of glycosaminoglycans in chondrocytes. Facilitated glucose transport represents the first rate-limiting step in glucose metabolism. This study examines molecular regulation of facilitated glucose transport in normal human articular chondrocytes by proinflammatory cytokines. IL-1beta and TNF-alpha, and to a lesser degree IL-6, accelerate facilitated glucose transport as measured by [(3)H]2-deoxyglucose uptake. IL-1beta induces an increased expression of glucose transporter (GLUT) 1 mRNA and protein, and GLUT9 mRNA. GLUT3 and GLUT8 mRNA are constitutively expressed in chondrocytes and are not regulated by IL-1beta. GLUT2 and GLUT4 mRNA are not detected in chondrocytes. IL-1beta stimulates GLUT1 protein glycosylation and plasma membrane incorporation. IL-1beta regulation of glucose transport in chondrocytes depends on protein kinase C and p38 signal transduction pathways, and does not require phosphoinositide 3-kinase, extracellular signal-related kinase, or c-Jun N-terminal kinase activation. IL-1beta-accelerated glucose transport in chondrocytes is not mediated by endogenous NO or eicosanoids. These results demonstrate that stimulation of glucose transport represents a component of the chondrocyte response to IL-1beta. Two classes of GLUTs are identified in chondrocytes, constitutively expressed GLUT3 and GLUT8, and the inducible GLUT1 and GLUT9. 相似文献
3.
No consensus exists concerning the mechanisms, distribution,or adaptive significance of consciousness. Agreement on anyone of these issues would aid in resolving others. Given a reliablebehavioral or neuroanatomical test for consciousness, we couldmap its distribution and describe its evolution. Conversely,if we knew its distribution, we could assess its adaptive valueand look for similarly distributed neuroanatomies to help usget at its mechanisms. Morgan's Canonthe rule that we should avoid attributinghumanlike mental states to other animals whenever possibleimpedesthe use of the comparative method in unraveling this knot. Ifinterpreted in this context as a parsimony criterion, Morgan'sCanon is logically equivalent to epiphenomenalism. It is parsimoniousif and only if conscious mental events play no causal role inhuman behavior and human consciousness has no adaptive significance.Rejecting this conclusion entails rejecting the parsimony interpretationof Morgan's Canon. 相似文献
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6.
Mapping of the gene for anti-müllerian hormone to the short arm of human chromosome 19 总被引:3,自引:0,他引:3
O Cohen-Haguenauer J Y Picard M G Mattéi S Serero V C Nguyen M F de Tand D Guerrier M C Hors-Cayla N Josso J Frézal 《Cytogenetics and cell genetics》1987,44(1):2-6
The gene coding for human anti-Müllerian hormone (AMH) was localized to subbands p13.2----p13.3 on chromosome 19, using in situ hybridization and Southern blot analysis of a panel of man-mouse and man-hamster somatic cell hybrids. 相似文献
7.
Fracture prediction for the proximal femur using finite element models: Part II--Nonlinear analysis. 总被引:2,自引:0,他引:2
In Part I we reported the results of linear finite element models of the proximal femur generated using geometric and constitutive data collected with quantitative computed tomography. These models demonstrated excellent agreement with in vitro studies when used to predict ultimate failure loads. In Part II, we report our extension of those finite element models to include nonlinear behavior of the trabecular and cortical bone. A highly nonlinear material law, originally designed for representing concrete, was used for trabecular bone, while a bilinear material law was used for cortical bone. We found excellent agreement between the model predictions and in vitro fracture data for both the onset of bone yielding and bone fracture. For bone yielding, the model predictions were within 2 percent for a load which simulated one-legged stance and 1 percent for a load which simulated a fall. For bone fracture, the model predictions were within 1 percent and 17 percent, respectively. The models also demonstrated different fracture mechanisms for the two different loading configurations. For one-legged stance, failure within the primary compressive trabeculae at the subcapital region occurred first, leading to load transfer and, ultimately, failure of the surrounding cortical shell. However, for a fall, failure of the cortical and trabecular bone occurred simultaneously within the intertrochanteric region. These results support our previous findings that the strength of the subcapital region is primarily due to trabecular bone whereas the strength of the intertrochanteric region is primarily due to cortical bone. 相似文献
8.
To examine the effects of prepubertal steroid environment on subsequent estrous cyclicity and gonadotropin secretion, Silastic implants containing 25, 50 or 100% 17 beta-estradiol (E2;n=34), 50% diethylstilbestrol (DES; n=16) or 50% testosterone (T; n=17) were placed into female rats at 12 days of age and removed on the day of vaginal opening (18-24 days of age). At 80 days of age, the percentages of regularly cycling females in the E2-(three groups combined), DES- and T-implanted groups were 59%, 0% and 59%, respectively. By 110 days of age, the percentages were reduced to 24%, 0% and 0%, and at 140 days of age 6%, 0% and 0%, respectively. Many of these females displayed irregular estrous cycles followed by a persistent estrous (PE) state. By contrast, 89% of the control females (blank implants or no implant) maintained regular cycles up to 140 days of age. At 150 days of age, an i.p. injection of gonadotropin-releasing hormone (GnRH; 100 ng/100 g BW) markedly increased serum luteinizing hormone (LH), but not follicle-stimulating hormone (FSH), in intact PE females treated prepubertally with E2 implants. After the test with GnRH, PE rats were ovariectomized (OVX). Thirty days after OVX, similar GnRH administration significantly increased serum levels of both LH and FSH, but these responses were significantly (P less than 0.01) reduced when compared with those in OVX controls. Progesterone administration to estradiol benzoate-primed, acutely (3 days) OVX, or long-term (43 days) OVX-PE females did not increase LH or FSH release. These results indicate that exposure to exogenous estrogen or T prior to puberty precipitates the decline in estrous cyclicity associated with the loss of gonadotropin surge response, presumably due to an alteration in hypothalamic GnRH release. 相似文献
9.
Human colon carcinoma cells use multiple receptors to adhere to laminin: involvement of alpha 6 beta 4 and alpha 2 beta 1 integrins. 总被引:18,自引:2,他引:16 下载免费PDF全文
In this study, we used clone A, a human colon carcinoma cell line, to characterize those integrins that mediate colon carcinoma adhesion to laminin. Monoclonal antibodies specific for the human beta 1 subunit inhibited clone A adhesion to laminin. They also precipitated a complex of surface proteins that exhibited an electrophoretic behavior characteristic of alpha 2 beta 1 and alpha 3 beta 1. A monoclonal antibody specific for alpha 2 (PIH5) blocked clone A adhesion to laminin, as well as to collagen I. An alpha 3-specific antibody (P1B5) had no effect on clone A adhesion to laminin, even though it can block the adhesion of other cell types to laminin. Thus, the alpha 2 beta 1 integrin can function as both a laminin and collagen I receptor on clone A cells. Although these cells express alpha 3 beta 1, an established laminin receptor, they do not appear to use it to mediate laminin adhesion. In addition, the monoclonal antibody GoH3, which recognizes the alpha 6 integrin subunit, also inhibited carcinoma adhesion to laminin but not to fibronectin or collagen I. This antibody precipitated the alpha 6 subunit in association with the beta 4 subunit. There was no evidence of alpha 6 beta 1 association on these cells. In summary, the results obtained in this study indicate that multiple integrin alpha subunits, in association with two distinct beta subunits, are involved in colon carcinoma adhesion to laminin. Based on the behavior of alpha 3 beta 1 and alpha 2 beta 1, the results also suggest that cells can regulate the ability of a specific integrin to mediate adhesion. 相似文献
10.
Keith K.T. Lim Matt J. Kessler Kenneth P.H. Pritzker Jean E. Turnquist Paul A. Dieppe 《Journal of medical primatology》1996,25(4):301-308
Abstract: We describe the relative prevalence and pattern of distribution of osteoarthritis (OA) in the hands of elderly (>15 years) rhesus macaques using clinical, radiographic, and skeletal examinations. In the clinical study the prevalence of nodes was 72% and 16% in the distal inter-phalangeal joints (DIPJ) and proximal inter-phalangeal joints (PIPJ), respectively, 31% of all monkeys had polyarticular nodes. Radiographic OA was present in 55%, 9.1%, and 0% of the DIPJs, PIPJs, and thumb bases, respectively. Skeletal OA as defined by joint surface eburnation for the DIPJ, PIPJ, and thumb base were 16%, 8%, and 2%, respectively. A similar pattern of hand OA with humans is described except for the thumb base OA. This may be due to the relatively rudimentary manipulative role of the macaque thumb. The finding of polyarticular nodal OA raises the possibility of a common pathogenensis for IPJ OA amongst primates. 相似文献