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991.
神经细胞粘附分子在人脑星形细胞瘤中的表达 总被引:3,自引:1,他引:2
研究神经细胞粘附分子在人脑星形细胞瘤发生发展中的作用。方法:用原位杂交和免疫组织化学方法检测40例人脑星形细胞瘤组织中的NCAMmRNA及其蛋白(CD56)的表达。结果:星形细胞瘤1,2级中NCAMmRNA及蛋白的表达显著高于星形细胞瘤3,4级,核酸与蛋白水平的检测结论一致。结论:NCAMmRNA及其蛋白的表达与星形细胞瘤的恶性程度有关,NCAM的高表达可与星形细胞瘤的侵袭转有关,并有可能成为星形 相似文献
992.
胶质源性神经营养因子对脊髓损伤后前角运动神经元的保护作用 总被引:13,自引:2,他引:11
目的 :探讨胶质细胞源性神经营养因子 (GDNF)对脊髓损伤后运动神经元的保护作用。 方法 :大鼠分为假手术组、生理盐水 (NS)组和 GDNF组 ,改良 Allen法撞击致伤 T1 2 脊髓 ,蛛网膜下腔分别给予 NS和 GDNF,分别取不同时间的伤段脊髓进行切片 ,应用酶组织化学染色方法显示脊髓前角外侧核运动神经元中胆碱酯酶 (Ch E)和酸性磷酸酶 (ACP)活性 ,并结合计算机进行图像分析。结果 :GDNF组较 NS组 Ch E活性显著增加 ,ACP活性显著降低 ;2 1d时 NS组的 ACP及 Ch E活性均高于及低于假手术组 ;GDNF组与假手术组 Ch E和 ACP活性差别不显著。 结论 :GDNF对脊髓损伤后的前角外侧核运动神经元有一定的保护作用 相似文献
993.
免疫磁珠法分选胚胎大鼠脑神经干细胞的初步研究 总被引:11,自引:1,他引:10
目的:探索应用免疫磁珠间接阳性法分选神经上皮干细胞蛋白(nestin)阳性的神经干细胞群的实验条件,为研究神经干细胞的特性与神经干细胞的培养和移植研究创造有利条件。方法:制取胎鼠大脑组织细胞悬液,免疫磁珠法分选胎鼠脑神经干细胞,以流式细胞术检测阳性细胞纯度,以锥虫蓝染色法检测细胞活性。结果:该法分选的nestin阳性细胞纯度为93.0%~99.7%,其中活性细胞为92%~97%。结论:免疫磁珠法分离胎鼠脑神经干细胞群落简便、有效,可以为神经干细胞细胞培养和移植提供细胞来源,也为研究高纯度神经干细胞的特性提供了实验基础。 相似文献
994.
大鼠急性氧中毒后全脑细胞能量代谢的活体^31P磁共振谱 … 总被引:1,自引:0,他引:1
目的:探讨大鼠急性氧中毒后脑的能量代谢产物与脑细胞内PH变化的规律。方法:采用磁共振方法,用4.7T动物磁共振谱仪,检测氧中毒后不同时程各种磷酸化合物与无机磷酸根(Pi)、磷酸肌酸(PCr)与γ-ATP以及β-ATP与Pi之间的比值,并根据Pi的化学位移推算脑细胞内PH值。结果:氧中毒组物舱1和3小时后PCr/Pi,PCr/γ-ATP以及β-ATP/Pi值均显著降低;5h后恢复正常;24和48小时 相似文献
995.
目的 :考察双氯芬酸钠微乳在家兔体内的药代动力学过程。方法 :家兔单次口服双氯芬酸钠微乳和双氯芬酸钠混悬液后 ,用 HPL C法测定血中双氯芬酸钠浓度。 结果 :双氯芬酸钠微乳和混悬液的 AU C0 -∞ 分别为 13.45 6和 10 .5 84μg· h· m l- 1 ,cmax 1 为 2 .85 2和 3.145 μg/m l,tmax1 为 1.438和 0 .75 0 h。 结论 :双氯芬酸钠微乳在家兔体内吸收过程较为平缓 ,可在较长时间内维持一定的血药浓度。 相似文献
996.
Objective To investigate variations in hepatitis B virus (HBV) polymerase gene in chronic HBV infected patients resistant to lamivudine therapy. Methods Specimens were obtained from nine patients with chronic HBV infection, who were resistant to lamivudine therapy. Partial segments of the HBV DNA polymerase gene we re amplified by polymerase chain reaction (PCR). Nucleotide sequence was performed using an applied 373 automated sequencer. Titre of HBV DNA was measured by branched DNA assay (Chiron). Results Of nine patients with HBV DNA positive after 64 weeks of treatment, five (56%) had variations in the highly conserved YMDD motif in domain C of the HBV polymerase, three of those were substitutions of isoleucine for methionine(M), and two were substitutions of valine(V) for methionine. Additionally, in two patients with variations characterized by substitutions of V for M, one had a simultaneous amino acid change from the first aspartic acid to glycine and this pattern of variation was not reported in other literatures. With respect to viremia, in two subjects with low titre of HBV DNA (<100 MEq/ml), no variation was found in the YMDD motif, whereas in seven patients with high titre of HBV DBA (>300 MEq/ml), five (71%) had variations in the YMDD motif. Conclusions Lamivudine is a potent anti-viral agent for treatment of chronic HBV infection. Resistance to lamivudine is likely caused by the variations in the YMDD motif of the HBV polymerase gene. 相似文献
997.
Objective To evaluate apoptosis in lupus nephritis and the relationship between the existe nce of apoptotic cells in renal tissue and histopathological or clinical changes .Methods Apoptosis was detected by in situ nick-end labeling techniques (TUNEL) in renal biopsies from 25 patients with type Ⅳ lupus nephritis (LN), 12 patients with I gA nephropathy IgAN, 4 patients with idiopathic mesangioproliferative glomerulon ephritis (MsPGN) and 3 patients with acute poststreptococcal glomerulonephritis (APGN).Normal renal tissue obtained at nephrectomy for hypernephroma in 4 adul ts was used as control.Proliferating cells were identified by proliferating ce ll nuclear antigen (PCNA) in these patients. Results Compared to other proliferative glomerulo-nephritis and controls, the patients w ith lupus nephritis had less apoptotic cells, a higher ratio of PCNA+ cells/TdT+ cells (P/T) in renal tissues; and their P/T ratio in glomeruli and tubuloin terstitium correlated with the chronicity index, r=0.4983 (P=0.0132), r=0.8399 (P<0.001), r=0.6614 (P=0.0033), respectively.P/T ratios in the glomerulus and tubule had a positive correlation with 24-hour uri nary protein, r=0.8554 (P<0.001) and r=0.7134 (P=0.001); and a negative correlation with creatinine clearance (Ccr), r=-0.4880 (P=0 .0133) and r=-0.7229 (P=0.001), which in tubules positively corre lated with serum creatinine (Scr), r=0.4107 (P=0.0414).Conclusions Apoptosis is reduced in proliferative lupus nephritis.Intense proliferation wi thout a commensurate increase in apoptosis is a possible mechanism that leads to chronic progressive renal histopathological changes. 相似文献
998.
上海社区糖尿病前期及糖尿病人群视网膜病变患病率及相关危险因素分析 总被引:1,自引:0,他引:1
Objective To determine the prevalence and risk factors of diabetic retinopathy (DR) in the Diabetes Mellitus (DM) and impaired glucose regulation (IGR) population in Shanghai Community. Methods DR screening after the epidemiologic study of metabolic syndrome in Huayang and Canyang Community , Shanghai was conducted among 1300 patients with DM or IGR during June 2005 and March 2006, Digital non-mydriatic fundus photography was performed for each eye in all subjects. Other factors, including diabetes related history, BMI, WHR, fasting plasma glucose, HbAlc, serum lipid and blood pressure were also assessed. 642 patients,312 males and 330 females, aged 65 ± 13, with complete data were enrolled into the analysis. Results The prevalence of DR was 19. 9% in the diabetic population, and the prevalence of mild, moderate, severe non-proliferative retinopathy and proliferative retinopathy was 12. 0%, 5. 1%, 2. 3% and 0. 5%, respectively; the prevalence of DR in IGR reached 8. 0%. Logistic regression analysis revealed that HbA1c level and diabetes duration were both independently associated with diabetic retinopathy. Conclusion The prevalence of DR was high in both DM and IGR population. Bad blood glucose control and long diabetes duration both increased occurrence of DR. 相似文献
999.
Objective To evaluate the role of endogenous ouabain (EO) in the development of hypertension and the characteristics of EO secretion in 1k1c (one kidney, one clipped) hypertensive rats. Methods EO content of serum and tissues in 1k1c hypertensive rats and normal control Sprague-Dawley (SD) rats was detected by the method of enzyme linked immunosorbent assay (ELISA). The relationship between serum or tissue ouabain and blood pressure was analyzed in 1k1c hypertensive rats. Results The ouabain content of serum, heart, kidney, adrenal gland, pituitary and hypothalamus was significantly higher in 1k1c hypertensive rats than that in normal control SD rats (2.25, 2.63, 3.35, 40.37, 3.34, 15.7 μg/kg tissue in 1k1c hypertensive rats vs 1.12, 1.79, 1.73, 27.54, 1.83, 10.10 μg/kg tissue in control SD rats, respectively. P<0.05 for all of these comparisons). The ouabain content of the adrenal gland and the hypothalamus was higher than that of other tissues or serum, both in 1k1c rats and in control SD rats. The EO content of serum, kidney and hypothalamus was significantly correlated with blood pressure in 1k1c hypertensive rats (r=0.59, 0.63, 0.52, respectively. P<0.05). The ouabain content of heart, liver, adrenal gland and pituitary was not correlated with blood pressure. Conclusions EO might play an important role in the development of hypertension in 1k1c hypertensive rats. The adrenal gland may be a major source of EO and the hypothalamus-pituitary-adrenal axis may be involved in the regulation of EO secretion. 相似文献
1000.
Laminin(LN)isamajornoncollagenousglycoproteininbasementmembranesIthasbeenreportedthatLNcouldaffectanumberofbiologicbehaviorsofcarcinomacellsmediatedbytheLNreceptors1 ItisknownthattheNlinkedcomplextypecarbohydratechainsonLNareinvolvedintherecognitionan… 相似文献