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81.
82.
转化生长因子α,β1对大鼠肺泡Ⅱ型细胞生长的影响 总被引:2,自引:0,他引:2
目的 探讨转化生长因子α和β1对肺泡Ⅱ型细胞增生的影响及其作用机制。方法 采用原代培养的成年大鼠肺泡Ⅱ型细胞,加入TGFα、TGFβ1作用48小时,测定肺泡Ⅱ型细^3H-TdR掺入量和细胞数量,并用斑点杂交、原位杂交和免疫组化方法检测细胞内细胞周期蛋白D1、细胞周期依赖性激酶4 mRNA和蛋白的表达。结果 随TGFα浓度递增,肺泡Ⅱ型细胞^3H-TdR掺入量和细胞数量均逐渐增加,呈量效正相关;TG 相似文献
83.
Intratracheal administration of liposomal clodronate accelerates alveolar macrophage reconstitution following fetal liver transplantation 总被引:1,自引:0,他引:1
Everhart MB Han W Parman KS Polosukhin VV Zeng H Sadikot RT Li B Yull FE Christman JW Blackwell TS 《Journal of leukocyte biology》2005,77(2):173-180
To facilitate study of alveolar macrophages in vivo, we developed a method to rapidly and efficiently replace resident alveolar macrophages with macrophages of a different (donor) genotype. Chimeric mice were generated by lethal irradiation followed by fetal liver transplantation (FLT) using green fluorescent protein (GFP) transgenic reporter mice as donors. Kinetics of peripheral blood monocyte (PBM) and alveolar macrophage reconstitution was determined 4 and 10 weeks post-FLT by quantifying the percentage of GFP+ cells. To enhance the recruitment of donor monocytes into the lung after FLT, mice were treated with intratracheal administration of liposomal clodronate to deplete host alveolar macrophages at 6 weeks post-FLT. PBM reconstitution occurred by 4 weeks after FLT (85.7+/-1.6% of CD11b+/Gr-1+ monocytes were GFP+), and minimal alveolar macrophage repopulation was observed (9.5% GFP+). By 10 weeks following FLT, 48% of alveolar macrophages were GFP+ by immunostaining of macrophages on lung tissue sections, and 55.1 +/- 1.6% of lung lavage macrophages were GFP+ by fluorescein-activated cell sorter analysis. Clodronate treatment resulted in a significant increase in GFP+ alveolar macrophages 10 weeks after FLT. By immunostaining, 90% of macrophages were GFP+ on lung tissue sections and 87.5 +/- 1.1% GFP+ in lung lavage (compared with GFP-transgenic controls). The ability of newly recruited alveolar macrophages to clear Pseudomonas aeruginosa and activate nuclear factor-kappaB in response to Eschericia coli lipopolysaccharide demonstrated normal macrophage function. Optimizing this methodology provides an important tool for the study of specific genes and their contribution to alveolar macrophage function in vivo. 相似文献
84.
Localization of plasminogen activator and inhibitor, LH and androgen receptors and inhibin subunits in monkey epididymis 总被引:4,自引:1,他引:4
Epididymis is a site of sperm maturation and storage. Limited and
directed-proteolysis regulated by plasminogen activator (PA), plasminogen
activator inhibitor type-1 (PAI-1) and other related factors may play an
essential role in these processes. Our previous studies have demonstrated
that rat epididymis expressed luteinizing hormone receptor (LHR), tissue
type (t) and urokinase type (u)PA, mRNAs, and tPA activity was stimulated
in vitro by human chorionic gonoadotrophin (HCG). In the present study we
further examined localization of mRNAs for tPA, uPA, LHR, androgen receptor
(AR), as well as inhibin subunits alpha, betaA and betaB in rhesus monkey
epididymis. Using in-situ hybridization with digoxygenin-labelled cRNA
probes, we have demonstrated that tPA and PAI-1 mRNAs were localized in
epithelial cells of adult monkey epididymis. uPA mRNA was localized in the
same areas, but to a much smaller extent. tPA, uPA and PAI-1 mRNAs were
greatly expressed in the caput and corpus of adult epididymis than in other
regions. In-vitro experiments showed that both tPA and uPA activities in
epididymal cells were dramatically stimulated by HCG, but not by follicle
stimulating hormone (FSH). LHR (but not FSH receptor) and AR mRNAs were
localized in the epithelial cells of the epididymis. However, LHR mRNA was
detected in both adult and immature infant monkeys, whereas AR was found
only in the adult. Inhibin alpha, betaA and betaB mRNAs were also detected
in this organ, betaA mRNA being more strongly expressed in the caput than
in other regions of the epididymis. We suggest that LH and androgen may be
the key hormones in coordination with the PA-PAI-1 system in regulating
epididymal differentiation and sperm maturation.
相似文献
85.
In this paper, we developed an analytical fan-beam reconstruction algorithm that compensates for uniform attenuation in SPECT. The new fan-beam algorithm is in the form of backprojection first, then filtering, and is mathematically exact. The algorithm is based on three components. The first one is the established generalized central-slice theorem, which relates the 1D Fourier transform of a set of arbitrary data and the 2D Fourier transform of the backprojected image. The second one is the fact that the backprojection of the fan-beam measurements is identical to the backprojection of the parallel measurements of the same object with the same attenuator. The third one is the stable analytical reconstruction algorithm for uniformly attenuated Radon data, developed by Metz and Pan. The fan-beam algorithm is then extended into a cone-beam reconstruction algorithm, where the orbit of the focal point of the cone-beam imaging geometry is a circle. This orbit geometry does not satisfy Tuy's condition and the obtained cone-beam algorithm is an approximation. In the cone-beam algorithm, the cone-beam data are first backprojected into the 3D image volume; then a slice-by-slice filtering is performed. This slice-by-slice filtering procedure is identical to that of the fan-beam algorithm. Both the fan-beam and cone-beam algorithms are efficient, and computer simulations are presented. The new cone-beam algorithm is compared with Bronnikov's cone-beam algorithm, and it is shown to have better performance with noisy projections. 相似文献
86.
Qian KX Zeng P Ru WM Yuan HY Feng ZG Li L 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2002,48(3):290-292
Our former work demonstrated that our impeller pump could support the circulation of experimental animals for several months without harm to blood elements or organ function. The termination of the experiments was mostly related to wear of the mechanical bearing and thrombosis along the bearing. To solve the bearing problem, we investigated a magnetic bearing in our lab, which resulted in some new problems, such as complicated design and control, considerable energy consumption, and lesser reliability. Progress in developing an impeller pump for long-term application has recently been achieved. Instead of using a sliding bearing system, we devised a rolling bearing system. Its service life is more than 10 years because of a wearproof roller made of ultra high molecular weight polythene. To avoid thrombus formation, we introduced a special purge system to the bearing, allowing the saline with heparin to be infused through the bearing into the pump. The bearing, therefore, keeps working in the saline, and no thrombus will be formed. Animal experiments demonstrated that a 30 ml fluid infusion per hour is enough to prevent thrombus formation. With these improvements, the impeller pump has continuously run for 8 months, and no bearing wear can be measured. The device, weighing 150 g, is fully implantable, consumes approximately 9.6 watts, and delivers a 9L/min blood flow against a 120 mm Hg mean pressure and reaches a highest total efficiency of 24.7% for the motor (including the controller) and pump. The system can produce both pulsatile and nonpulsatile flow according to requirements. 相似文献
87.
88.
A patient with Waardenburg syndrome type II associated with Hirschsprung megacolon and Marcus Gunn ptosis is presented. It is suggested that these different anomalies are manifestations of the same neurocrestopathy. 相似文献
89.
Jocelyne Fleury-Feith Laurence Kheuang Lin Zeng Jean Bignon Christian Boutin Isabelle Monnet Marie-Claude Jaurand 《The Journal of pathology》1995,177(2):209-215
The aim of this study was to determine, by transmission electron microscopy, the differentiation features of 21 human malignant mesothelioma cell lines (HMCLs) established from 13 specimens of 12 confirmed human malignant mesotheliomas, and of tumours induced in nude mice injected with 16 HMCLs. Fifty per cent of HMCLs showed typical mesothelial differentiation (long and slender microvilli, desmosomes, perinuclear intermediate filaments); 29 per cent did not show differentiation; and the remainder were poorly differentiated. Three human tumour specimens gave several different HMCLs; the cell lines obtained from a given tumour exhibited variable mesothelial differentiation. Eleven HMCLs were compared with the native tumour. Four were similar to the tumour and seven were less well differentiated, in most cases in relation to their microvilli. With six HMCLs, tumours induced in nude mice were less well differentiated than the corresponding cell lines, whereas with four HMCLs, tumours were equally or better differentiated. However, in most nude mice tumours, typical mesothelial microvilli were present. These results show that cell lines established from malignant mesothelioma may exhibit dedifferentiated features. However, while the variability in ultrastructural differentiation may result from the culture microenvironment, it could also be related to the state of differentiation, of the native tumour sample and to tumour cell heterogeneity. 相似文献
90.
Correlation of AIB1 overexpression with advanced clinical stage of human colorectal carcinoma 总被引:7,自引:0,他引:7
AIB1, a member of the steroid receptor coactivator 1 family, has been cloned on 20q12 and is a candidate oncogene in human breast cancer. It is commonly amplified and overexpressed in several types of human cancers. In this study, we examined the expression of AIB1, as related to clinicopathologic features, in 85 human colorectal cancers (CRCs). The status of the number of AIB1 copies, p53 expression, and DNA ploidy was also analyzed. The overexpression of AIB1 was detected in 35% of CRCs. Amplification of AIB1 was observed in 10% of CRCs. In addition, the overexpression of AIB1 was observed more frequently in CRCs in later clinical stages (T3 N1 M0/T3 N0 2M1), compared with that in T3 N0 M0 stage (P < .05). These results suggest that overexpression of AIB1 might provide a selective advantage for the developmental growth and/or progression of subsets of CRCs. In addition, a significant correlation (P < .05) of overexpression of AIB1 with p53 overexpression as well as with aneuploid DNA content was observed in these CRCs. The overexpression of p53 was also correlated significantly with CRC DNA ploidy (P < .05). Furthermore, there was a substantial population of CRCs showing overexpression of both AIB1 and p53 protein and all had aneuploid DNA content; most of these were in the later clinical stage. These findings suggest a possible convergence of AIB1 with a pathway involving p53, which might induce chromosomal instability and affect the clinical phenotype of a subset of CRCs. 相似文献