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81.
本文报道给C57小鼠腹腔注射不同剂量1-甲基-4-苯基-1,2,3,6-四氢吡啶(MPTP)后,发现组3(MPTP35 mg/kg,每天一次,共7天)鼠肝匀浆、线粒体和微粒体的膜丙二醛含量明显增加,与对照组相比分别增加70.5%,67%和51.4%(P<0.01),而组1(MPTP 35mg/kg,每4小时一次,共3次)和组2(MPTP35mg/kg,每天一次,共4天)鼠肝丙二醛含量与对照组相近。结果表明MPTP有明显地促进鼠肝脂质过氧化的作用,并与其剂量有关。 相似文献
82.
Buprenorphine, a partial mu-opioid receptor agonist, has been proposed as a treatment for cocaine abuse. However, studies
in animals have produced conflicting results on the nature of the interaction between buprenorphine and cocaine. In some studies,
buprenorphine attenuated the effects of cocaine and in others it enhanced them. The purpose of the present study was to evaluate
the interaction of buprenorphine and cocaine on the rotational behavior of the nigrally-lesioned rat. Both buprenorphine (0.003–0.1
mg/kg) and cocaine (1.0– 30 mg/kg) alone produced dose-dependent increases in rotational behavior. Buprenorphine produced
long-lasting turning with a peak at 60 min after administration, while cocaine produced turning that peaked immediately after
administration and lasted for about 2 h. To distinguish simple additivity from other possible outcomes, we determined the
relative potency of each drug alone, using a defined level of effect: 150 turns above the saline control in 4 h. This effect
was produced by 10.0 mg/kg cocaine alone and by 0.0175 mg/kg buprenorphine alone. Based on these results, fixed ratio combinations
were tested and the experimentally derived effects were compared to the theoretically additive values, using an isobolographic
analysis. The fixed ratio combinations of the two drugs tested produced turning greater than predicted from simple additivity.
This finding provides statistically-supported evidence for synergism between the actions of buprenorphine and cocaine.
Received: 28 January 1997 / Final version: 7 June 1997 相似文献
83.
84.
Ryoji Tanei Tatsuo Yamamoto Hideki Yokono Tadashi Motoori 《The Journal of dermatology》1997,24(8):514-521
We report a case of an 81-year-old woman in whom lichenoid eruptions and Sjögren-like sicca syndrome developed 45 days after cholecystectomy. During surgery, one unit (130 ml) of unirradiated packed red blood cells from a male donor was transfused. The lichenoid eruptions cleared up with exfoliation; however, sicca symptoms remained during the follow-up period of four years. Histological examinations of both skin and lip biopsy specimens were in agreement with those of graft-versus-host disease (GVHD). A Y-chromosomal body was identified in the lymphocytes in the skin lesion by staining with quinacrine dihydrochloride and in the lip lesion by a method with in situ hybridization. The findings suggest that this case demonstrated the manifestations of non-fatal transfusion-associated GVHD. 相似文献
85.
R. Gottschalk C. Seidl T. Löffler E. Seifried D. Hoelzer J.P. Kaltwasser 《Tissue antigens》1998,51(3):270-275
Abstract: Genetic hemochromatosis (GH) is closely associated with genes of the major histocompatibility complex (MHC) on chromosome 6. Recently, a candidate gene for GH, with structural similarities to MHC class I genes, designated HLA-H and presently named HFE, has been cloned. The HFE gene is localized telomeric to the MHC and several reports have indicated that the HFE gene is mutated in GH patients. In the present study we have analyzed the relationship of HFE gene variants and disease manifestation in GH patients and family members. Fifty-seven patients with GH, 73 family members and 153 healthy blood donors were studied for the amino acid dimorphism at codon 63 (His63Asp=H63D) and codon 282 (Cys282Tyr= C282Y) of the HFE gene. The codon 63 and 282 dimorphism were defined by PCR amplification of genomic DNA samples and restriction enzyme digestion using RsaI/SnaBI for C282Y and Bcll/Mbo 1 for H63D. Ferritin, transferrin serum levels and total iron-binding capacity were determined prior to therapeutic intervention. The Tyr-282 substitution occurred in 53 (93%) of patients compared with 8 (5.2%) of controls (OR=169, P >0.0001). Fifty-one (90%) patients were Tyr-282 homozygous. In contrast, the Asp-63 substitution was present in 5 (8.8%) of the patients compared with 34 (22%) of controls (OR=0.39, P =NS) with none of the patients being homozygous. In Tyr-282 homozygous GH patients serum ferritin levels, transferrin saturation, liver iron and liver iron index were elevated significantly compared to Tyr-282-negative patients, whereas no difference was observed between Tyr/Cys-282 heterozygous and Tyr-282-negative patients. 相似文献
86.
Human prostate cancer (PC) cell lines possess epidermal growth factor (EGF) receptors and secrete EGF-related polypeptides. We used an EGF receptor-blocking antibody (anti-EGF.R) to demonstrate a functional autocrine loop, as well as the interaction between this and the effects of linoleic acid (LA), an omega-6 fatty acid, on PC cell growth. The anti-EGF.R competed effectively with [125I]EGF for receptors on DU145 PC cells, and on a high-passage DU145 variant (DU145M); when added to the culture medium, it suppressed both DU145 and DU145M cell growth in a dose-dependent manner. LA, a precursor for eicosanoid synthesis, had little effect on DU145 cell growth rate but stimulated DU145M growth in a concentration-related manner over a range of 0.25-2.0 micrograms/ml. anti-EGF.R (10(-9) M) caused suppression of LA-stimulated growth of DU145M cells in serum-free medium, which was prevented by the addition of 2 nM EGF. We conclude that an EGF.R-mediated autocrine loop is involved in PC cell growth regulation and that at least one site of action may be the synthesis of eicosanoids from their LA precursor. 相似文献
87.
风湿性心脏病二尖瓣置换术中细胞因子水平的变化 总被引:1,自引:0,他引:1
目的测定风湿性心脏病二尖瓣置换术中细胞因子水平,了解它们的变化规律。方法 11例体外循环(CPB)下二尖瓣置换术患者,分别于术前,主动脉阻断前,主动脉阻断后5min,主动脉开放后10min、1h、2h、4h、24h测定白介素6(IL-6)、白介素8(IL-8)、白介素10(IL-10)以及肿瘤坏死因子(TNF)。结果IL-6、IL-8、IL-10水平在CPB开始后逐渐升高,在主动脉开放后2h左右达到高峰(P<0.01)。之后逐渐下降,到主动脉开放后24h已显著下降。TNF水平在CPB开始后逐渐升高,在主动脉开放后24h仍维持在很高的水平(P<0.01)。结论CPB下二尖瓣置换术中既有促炎因子水平的升高,又有抗炎因子的激活。 相似文献
88.
目的 探讨可溶性白细胞介素 2受体 (sIL 2R)和可溶性白细胞介素 6受体 (sIL 6R)在多发性硬化(MS)发病过程中的作用。方法 采用双体夹心ELISA法对 2 9例MS急性期患者及 2 0例炎性神经病患者、39例非炎性神经病患者、2 0例健康对照者脑脊液和血清中sIL 2R和sIL 6R的含量进行检测。结果 MS患者血清和脑脊液中sIL 2R、sIL 6R含量明显高于非炎性神经病组 (P <0 .0 5 )及健康对照组 (P <0 .0 1) ;MS组sIL 2R和血清sIL 6R含量与炎性神经病组比较 ,无显著性差异 ,但脑脊液中sIL 6R水平明显低于炎性神经病组 (P <0 .0 1)。结论 sIL 2R和sIL 6R在MS急性期患者体内明显升高 ,进一步证实了MS有关免疫学的发病机制 ,并为临床诊断MS提供了具有参考价值的实验室指标 相似文献
89.
杀菌性通透性增强蛋白对失血性休克的保护作用及其机理 总被引:2,自引:0,他引:2
分别在失血和复苏开始即刻iv杀菌性/通透性增强蛋白(BPI)1.5和3.5mgkg-1,观察BPI对大鼠失血性休克转归的影响.结果显示,BPI治疗能明显改善失血性休克大鼠肝肾功能,提高休克动物存活率(BPI组81%vs休克对照组44%,P<0.05),BPI组大鼠复苏后与休克前的血浆内毒素(0.20±0.04vs0.24±0.05kUL-1)水平无明显变化,血浆肿瘤坏死因子α和白介素6水平较休克前明显升高,但均显著低于休克对照组.提示BPI对失血性休克大鼠具有一定的保护作用,其机理可能与BPI拮抗休克时内源性内毒素活性,抑制细胞因子反应有关. 相似文献
90.
Gen Matsuo Yasuo Matsumura Kiyoshi Tadano Takashi Hashimoto Shiro Morimoto 《Clinical and experimental pharmacology & physiology》1997,24(7):487-491
1. The effects of sarafotoxin S6c (S6c), a selective endothelin ETB receptor agonist, on renal haemodynamics and urine formation were examined in anaesthetized dogs. 2. Intrarenal arterial infusion of S6c at a rate of 1 or 5 ng/kg per min produced a transient increase in renal blood flow (RBF), with no change in systemic blood pressure and heart rate; RBF then decreased gradually to below the basal value. There were significant and dose-dependent increases in urine flow and free water clearance and decreases in urine osmolality during S6c infusion, whereas urinary excretion of sodium and glomerular filtration rate (GFR) remained unchanged. Simultaneously, S6c administration elicited a marked increase in urinary excretion of nitric oxide (NO) metabolites, N02? and N03? (UNO*V). 3. In dogs simultaneously administered S6c (5 ng/kg per min) and iVG-nitro-L-arginine (NOARG; 40 (jig/kg per min), a NO synthase inhibitor, the renal vasodilator effect of S6c was abolished and marked reductions in RBF and GFR were observed. The S6c-induced diuretic action was not affected by NOARG. In the presence of NOARG, there was a small amount of UNOxV at the basal level and the administration of S6c did not increase UNOxV. 4. These results suggest that an intrarenal arterial infusion of S6c enhances the production of NO in the kidney and that this enhancement contributes to the peptide-induced renal vasodilation. In contrast, it is unlikely that S6c-induced water diuresis is related to NO production stimulated by this peptide. 相似文献