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71.
72.
Anthropometric data on 110 myelomeningocele (MMC) subjects in relation to age, sex, level of lesion and ambulation were studied to investigate growth and the occurrence of obesity in MMC. In 52 subjects, indices of obesity were validated against body composition analysis of total body fat (%BF) using body potassium and body water techniques. Most subjects were short and light compared to reference data and became relatively shorter and heavier with age. Overall trunk growth was not affected by the level of lesion, but sitting height was affected by kyphoscoliosis. Arm spans were similar to reference data, but were significantly greater in wheelchair users. Leg length was greatest in those who walked. Body composition data showed excess adipose in many MMC subjects, this tendency increasing with age. When correlated with %BF determined from body composition analysis, common clinical indices of obesity had variable r values (wt/ht2 0.78; wt/sitting ht2 0.77; upper arm fat area 0.75; triceps skinfold 0.74; wt/arm span2 0.68, with the 4 skinfold method correlating best, 0.82). Anthropometric measures, taken with cognizance of level of disability and mobility, can accurately assess body growth and the occurrence of obesity in MMC. The influence of ambulatory activity in promoting normal growth is emphasized. 相似文献
73.
G. J. Breur M. D. Lapierre K. Kazmierczak K. M. Stechuchak G. P. McCabe 《Calcified tissue international》1997,61(5):418-425
In this study, we tested the hypotheses that (a) both the domain volume (volume of the cell and the matrix it has formed)
and matrix volume of juxtametaphyseal hypertrophic chondrocytes in the growth plate is tightly controlled, and that (b) the
domain volume of juxtametaphyseal hypertrophic chondrocytes is a strong determinant of the rate of bone length growth. We
analyzed the rate of bone length growth (oxytetracycline labeling techniques) and nine stereologic and kinetic parameters
related to the juxtametaphyseal chondrocytic domain in the proximal and distal radial and tibial growth plates of 21- and
35-day-old rats. The domain volume increased with increasing growth rates, independent of the location of the growth plate
and the age of the animal. Within age groups, the matrix volume per cell increased with increasing growth rates, but an identical
growth plate had the same matrix volume per cell in 21- and 35-day-old rats. The most suitable regression model (R
2= 0.992) to describe the rate of bone length growth included the mean volume of juxtametaphyseal hypertrophic chondrocytes
and the mean rate of cell loss/cell proliferation. This relationship was independent of the location of the growth plate and
the age of the animal. The data suggest that the domain volume of juxtametaphyseal hypertrophic chondrocytes, as well as the
matrix volume produced per cell, may be tightly regulated. In addition, the volume of juxtametaphyseal hypertrophic chondrocytes
and the rate of cell loss/rate of cell proliferation may play the most important role in the determination of the rate of
bone length growth.
Received: 2 December 1996 / Accepted: 24 March 1997 相似文献
74.
目的研究托吡酯(TPM)对慢性癫痫大鼠海马碱性成纤维细胞生长因子(bFGF)表达的影响。方法制作戊四氮(PTZ)慢性癫痫点燃大鼠模型,分为PTZ组、TPM组及正常对照组,每组又以5d、10d、15d3个时间点各分为3小组。免疫组化法观察各组海马CAl、CA3区及齿状回bFGF表达,HE染色观察病理形态学改变。结果(1)行为学观察:PTZ组和TPM组在癫痫发作上无明显差别。(2)bFGF表达:①各组齿状回区bFGF表达:PTZ组和TPM组各时点表达不断增高,与正常对照组比较差异有统计学意义(均P〈0.01),尤以10d及15d时增高更明显,与5d时比较差异有统计学意义(均P〈0.05)。②各组CAl区bFGF表达:PTZ组各时点均有明显表达,且随时间延长而表达不断增高,各时点比较差异有统计学意义(均P〈0.01),与正常对照组比较差异有统计学意义(均P〈0.01);TPM组在5d时与正常对照组比较差异有统计学意义(P〈0.01),而10d、15d时逐渐下降,接近正常对照组水平。③各组CA3区bFGF表达:5d时3组比较差异无统计学意义。但PTZ组和TPM组在10d时与正常对照组比较差异有统计学意义(P〈0.01),PTZ组在15d时和TPM组及正常对照组比较差异有统计学意义(均P〈0.01)。(3)病理形态学改变:PTZ组和TPM组的海马CAl、CA3区尤其是CAl区可见较多神经元发生变性和坏死,PTZ组更显著。结论PTZ点燃过程中海马bF-GF表达增高,尤其在CAl区,且随时间延长有表达不断增高的趋势。TPM可能通过减少海马神经元损伤而明显下调海马CAl、CA3区bFGF的表达。 相似文献
75.
重度妊娠高血压综合征患者胎盘表皮生长因子受体的表达 总被引:1,自引:1,他引:0
目的:研究胎盘表皮生长因子受体(EGFR)蛋白及基因的表达在置度妊娠高血压综合征(妊高征)发病中的作用以及对妊高征胎儿生长发育的影响。方法:采用免疫组织化学法和逆转录-聚合酶链反应(RT-PCR)技术测定21例重度妊高征患者[分2组,重度妊高征合并胎儿宫内发育迟缓(IUGR)组9例和重度妊高征未合并IUGR组12例]胎盘EGFR的表达,并与15例正常妊娠者(对照组)比较。结果:与对照组相比,重度妊高征患者胎盘EGFR蛋白及其mRNA的表达显著降低(P<0.01),重度妊高征合并EGFR组与重度妊高征未合并IUGR组之间胎盘EGFR的表达差异无显著性(P>0.05)。结论:胎盘滋养层细胞EGFR表达显著降低,可能是重度妊高征发病的重要因素;如果EGFR的低表达发生较早,容易发生IUGR。 相似文献
76.
幕上星形细胞肿瘤MRI表现与VEGF、P16、Ki-67相关性研究 总被引:1,自引:0,他引:1
探讨星形细胞肿瘤MRI表现与P16、Ki—67、血管内皮生长因子(vascular endothelial growth factor,VEGF)表达的相关性。材料和方法:收集我院术前经MRI诊断并经手术病理证实的幕上星形细胞肿瘤53例,行常规平扫描后静脉注射Gd—DTPA增强成像;同时采用HE染色及链菌素生物素—过氧化酶连接法进行VEGF、Ki—67、P16的免疫组织化学染色,测定它们的表达指数。结果:星形细胞肿瘤的信号不均匀性、坏死、水肿、占位效应、强化程度与VEGF、Ki—67、P16的表达相关,且随着星形细胞肿瘤恶性程度的增高VEGF、Ki—67的表达增加;P16的表达率降低。结论:星形细胞肿瘤的MRI表现与VEGF、Ki—67、P16的表达密切相关,MRI可以间接判断星形细胞肿瘤的某些生物学行为。 相似文献
77.
转化生长因子在前列腺增生中作用的研究 总被引:1,自引:0,他引:1
目的:探讨转化生长因子α(TGF-α)和转化生长因子β(TGF-β)在良性前列腺增生症组织中的表达及意义。方法:利用免疫组织化学方法研究TGF-α和TGF-β在40例BPH组织和5例正常前列腺组织中的表达。结果:TGF-α在BPH组织上皮和间质中的表达强阳性率均高于正常前列腺组织(P<0.01)。且TGF-α在BPH组织上皮组织的表达明显高于其在间质中的表达(P<0.01)。TGF-β在BPH组织上皮和间质中的表达明显高于正常前列腺组织(P<0.01)。且TGF-β在BPH组织间质中的表达明显高于其在上皮组织中的表达(P<0.01)。结论:TGF-α在前列腺组织中表达增高,尤其在腔上皮细胞的胞浆中高度表达,TGF-β在前列腺包织中表达增高,尤其在间质组织中的过度表达,提示其可能直接或间接参与了前列腺间质细胞的分化和增殖,参与了BPH的病理过程。 相似文献
78.
移植肾组织TGF-β1和MMP-2表达及IV型胶原沉积与慢性移植肾肾病的关系 总被引:1,自引:0,他引:1
目的 探讨移植肾组织中转化生长因子β1(TGF-β1)和基质金属蛋白酶2(MMP-2)的表达及IV型胶原沉积与慢性移植肾肾病(CAN)的关系.方法 对18例CAN患者进行了移植肾切除术.光镜下观察切除的肾组织标本并根据其纤维化的程度进行分期,用免疫组织化学技术和图像分析法检测移植肾组织中TGF-β1和MMP-2表达量及IV型胶原沉积情况,并分析患者血肌酐(Cr)和尿素氮(BUN)的水平与移植肾纤维化程度的关系.结果 随着患者移植肾纤维化程度的加重,血清肌酐、尿素氮及肾组织中TGF-β1、IV型胶原基因表达量均增加,MMP-2表达量于移植肾纤维化早期明显升高,并随移植肾纤维化程度加重而逐渐降低.结论 移植肾组织中TGF-β1表达量增高及IV型胶原沉积可以促进CAN的进程,而MMP-2则可抑制其进展. 相似文献
79.
Summary An assay system for the measurement of the rate of Calcium Oxalate Monohydrate (COM) seed crystal growth in a metastable solution of calcium chloride and sodium oxalate containing traces of 14C-oxalic acid was used to assess the inhibitory activity of pyrophosphate (10–5 M-10–4 M), citrate (10–4 M-10–3 M) and urines of normal and pyridoxine deficient rats. Both pyrophosphate and citrate were strong inhibitors of COM crystal growth and caused a 50% decrease in crystal growth rate at 1.50×10–5 M and 2.85×10–4 M respectively. Normal rat urine strongly inhibited the COM crystal growth, while pyridoxine deficient animals showed a significant (p< 0.01) decrease in mean inhibitory activity as compared to pair-fed controls. A lowered urinary inhibitory potential accompanied with hyperoxaluria and hypercalciuria, which is known to be associated with pyridoxine deficiency, may be a contributory risk of calcium oxalate crystallization and stone formation. 相似文献
80.
H. Iwata A. Matsuyama N. Okumura S. Yoshida Y. Lee K. Imaizumi S. Shiosaka 《Brain research》1991,550(2):329-332
We examined the localization of basic fibroblast growth factor (basic FGF) in the adult rat brain by immunohistochemical and Western blotting analysis using a specific antibody against a synthetic basic FGF fragment (N-terminal 12 residues). The antibody did not cross-react with acidic FGF. Basic FGF-like immunoreactivity was located exclusively in the neuronal elements and had very heterogenous distribution. Immunoreactive cell bodies were observed in the paraventricular, supraoptic and circular nuclei of the hypothalamus. Numerous immunoreactive neuronal processes originating from these basic FGF-positive cells extended lateroventrally and then caudally to the internal layer of the median eminence. In addition, the neurohypophysis contained a significant number of basic FGF-like immunoreactive fibers. Western-blotting analysis revealed that the hypothalamus and the hypophysis contained a main band of basic FGF immunoreactive with an apparent molecular weight of 17 kDa. These results show that the hypothalamo-hypophyseal neuroendocrine pathway contains basic FGF. 相似文献