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81.
基因芯片对PMA激活的血管内皮细胞早期反应基因的研究 总被引:4,自引:1,他引:3
目的 :用基因芯片研究 PMA激活的血管内皮细胞的早期反应基因 (imm ediate early response gene,ERG)。方法 :以包含 40 96条人类基因的 DNA芯片检测血管内皮细胞受代谢增强剂 PMA(phorbol myristate acetate)激活后早期的基因表达谱 ,并从中筛查出 ERG。结果 :血管内皮细胞受 PMA作用 6 h后 ,17条基因上调 ,11条下调。数据处理聚类分析表明 17条上调基因中多数 (13/ 17)属蛋白质磷酸酶和转录调控因子基因 ,而下调基因中多数 (9/ 11)为细胞分裂相关基因。结论 :证明PMA激活的人血管内皮细胞早期反应基因主要是转录调控因子和蛋白质磷酸酶基因。 相似文献
82.
康渭东 《南通大学学报(哲学社会科学版)》2000,(4)
中国画的写意造型 ,展示的是似与不似之间、寓意于象、以象尽意“心物统一”的意象。在图形设计中采用写意造型方法 ,能使设计意念的表达更显符号化与象征性 ,同时也丰富观者感受层面与审美经验。 相似文献
83.
不同地区妇女产褥期卫生行为研究 总被引:22,自引:0,他引:22
目的 了解江苏、陕西和贵州三省妇女产褥期卫生行为和保健的一般情况;比较 不同地区间产褥期各种卫生行为的发生率;了解影响产褥期卫生行为的相关因素。方法 用问卷调查的形式对三者12个县的2352例2岁以下儿童母亲进行入户访问。结果 江苏、陕西、贵州三者产褥期各卫生行为的发和衣次为:洗头26.4%,38.8%,19.8%, 下身(指外阴部,下同)83.3%,26.9%,64.0%,正常活动76.9%,7 相似文献
84.
通过用抗CD3,CD28+CD80 McAb激活健康人的PBLs,并以PHA,IL-2,PBLs为对照组;对各组不同时间段的淋巴细胞超微结构进行观察。结果提示:CD3及CD28+CD80刺激淋巴细胞增殖外,也能使淋巴细胞活化,细胞表现为胞体增大,细胞器增多,具有粗大的绒毛和突出伪足,并可见单核细胞吞噬活跃。 相似文献
85.
From the roasted seeds ofCassia tora L., a new naphthopyrone glycoside was isolated and characterized as 10-[(β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl)oxyl-5-hydroxy-8-methoxy-2-methyl-4H-naphtho
[1,2-b]pyran-4-one(isorubrofusarin gentiobioside). Along with isorubrofusarin gentiobioside, alaternin and adenosine were isolated
and identified. 相似文献
86.
Penicillin sensor was prepared by immobilizing penicillinase (Pcase) on H+-selective carboxylated poly (vinyl chloride) (PVC-COOH) membrane or cellulose filter membrane. The immobilization techniques
are as follows. Pcase was immobilized with GTH on H+-selective PVC-COOH membrane or some amount of BSA was dropped on that membrane. Another method to make immobilization is
to mix type I Pcase with GTH and drop on a cellulose filter membrane. According to immobilization techniques, there were some
differences in response properties of enzyme electrodes, however, all electrodes responded to Pcase-resistant penicillin derivatives.
Pcase immobilized on cellulose filter membrane with H+-selective PVC membrane eletrode was more stable and more sensitive to penicillinase-resistant penicillin derivatives than
any other immobilization techniques. 相似文献
87.
We determined the microviscosity of synaptosomal plasma membrane vesicles (SPMV) isolated from bovine cerebral cortex and
liposomes of total lipids (SPMTL) and phospholipids (SPMPL) extracted from SPMV. Changes in the microviscosity induced by
the range and rate of lateral diffusion were measured by the intramolecular excimerization of 1,3-di(1-pyrenyl)-propane (Py-3-Py).
The microviscosity values of the direct probe environment in SPMV, SPMTL and SPMPL were 38.17, 31.11 and 27.64 cP, respectively,
at 37°C and the activation energies (Ea) of the excimer formation of Py-3-Py in SPMV, SPMTL and SPMPL were 8.236, 7.448 amd 7.025 kcal/mol, respectively. Probe location
was measured by polarity and polarizability parameters of the probe Py-3-Py and probe analogues, pyrene, 1-pyrenenonanol and
1-pyrenemethyl-3β-hydroxy-22,23-bisnor-5-cholenate (PMC), incorporated into membranes or solubilized in reference solvents.
There existed a good linear relationship between the first absorption peak of the1La band and the polarizability parameter (n
2−1)/(2n
2+1). The calculated refractive index values for SPMV, SPMTL and SPMPL were close to 1.50, which is higher than that of liquid
paraffin (n=1.475). The probe location was also determined by using a polarity parameter (f−1/2f1). Here f=(ε−1)/(2ε+1) is the dielectric constant function and f'=(n
2−1)/(2n
2+1) is the refractive index function. A correlation existed between the monomer fluorescence intensity ratio and the solvent
polarity parameter. The probes incorporated in SPMV, SPMTL, and SPMPL report a polarity value close to that of 1-hexanol (ε=13.29).
In conclusion, Py-3-Py is located completely inside the membrane, not in the very hydrophobic core, but displaced toward the
polar head groups of phospholipid molecules, e.g., central methylene region of aliphatic chains of phospholipid molecules. 相似文献
88.
Fu YL Hu YX Ling HL Ye ZZ Liang T Zhang MG Liu YK Kang B Luo YJ He SY Lian YJ 《Infectious diseases in obstetrics and gynecology》1994,1(5):235-241
Objective: The objective of this study was to determine whether human papillomavirus (HPV) infections are involved in the development of papillomatosis lesions of the lower female genital tract.Methods: A total of 616 biopsy specimens of genital papillomatous lesions (307 nodular and 309 papular types) from 598 patients were anaylyzed for the presence of HPV DNA sequences by polymerase chain reaction (PCR). These specimens were also examined by histopathological assessment for characteristic HPV-associated cytological changes, by immunohistochemical staining for HPV-associated antigen, and by electron microscopy for the presence of virions.Results: HPV DNA sequences were found in 97.9% (140 of 143 cases) and 1.1% (1 of 91 cases) of the nodular and papular papillomatosis cases tested, respectively. In 18 patients who had both types of papillomatosis lesions, HPV DNA was invariably found only in nodular tissues. HPV-associated antigen, koilocytosis, and virions were found in 53.6% (98 of 183 cases), 70.5% (129 of 183 cases), and 5.9% (5 of 85 cases) of nodular papillomatosis lesions tested, respectively.Conclusions: These data suggest that nodular papillomatosis was closely associated with HPV infection, but that papular papillomatosis of the lower female genital tract may have an etiology other than HPV infection. 相似文献
89.
90.
Regulation of type I collagen and interstitial collagenase mRNA expression in human dermal fibroblasts by colchicine and D-penicillamine 总被引:1,自引:0,他引:1
Sclerosis is a disease process in which idiopathic hardening occurs in the skin and/or internal organs as a result of the accumulation of type I collagen, induced mainly by transforming growth factor-beta. Colchicine and D-penicillamine are widely used for its treatment. Their effects are known to be due to post-translational down-regulation of type I collagen synthesis, with colchicine also up-regulating interstitial collagenase. To determine whether or not they have any pre-translational effect on type I collagen and MMP-1, and also to observe their effects on the action of TGF-beta, cultured neonatal foreskin fibroblasts were treated with colchicine and D-penicillamine, singly and together. The amount of type I collagen and MMP-1 mRNA were quantitated by Northern blot hybridization. Colchicine suppresses the basal level of type I collagen mRNA but minimally stimulates the mRNA expression of MMP-1, whereas D-penicillamine does not have any significant effects on either. Colchicine was also able to significantly suppress the TGF-beta-induced up-regulation of type I collagen mRNA expression. 相似文献