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91.
目的:设计合成靶向NF-κB的哑铃形“圈套”ODNs,并检测其对NF-κB转录活性和肾小球系膜细胞细胞因子(TNF-α和IL-6)表达的抑制效应。方法:以NF-κB顺式作用元件κB序列为模板,设计包含两个拷贝的κB序列,长度为58个碱基的环状ODNS,合成后部分序列做FAM标记,行转集效率鉴定实验。采用电泳迁移率改变实验(EMSA)体外检测哑铃形圈套ODNs对NF-κB转录活性的抑制效应。提取大鼠肾小球系膜细胞,随机分为正常对照组、LPS刺激组、哑铃形圈套ODNs处理组、无关圈套ODNs处理组和脂质体处理组。采用阳离子脂质体将2、4、8mg/L不同剂量哑铃形圈套ODNs转染大鼠肾小球系膜细胞,6h后用LPS刺激,收集转染后8、12、18上清和细胞。用酶联免疫吸附试验(ELISA)法检测上清细胞因子蛋白表达,逆转录PCR(RT-PCR)法检测细胞因子mRNA转录。结果:阳离子脂质体可将哑铃形圈套ODNs高效转集入肾小球系膜细胞,哑铃形圈套ODNs在体外能有效地抑制NF-κB与其顺式元件的结合;4、8mg/L剂量哑铃形圈套ODNs可明显抑制LPS诱导的大鼠肾小球系膜细胞TNF-α和IL-6转录与表达。结论:靶向N... 相似文献
92.
Preliminary assessment of fluorine-18 fluorodeoxyglucose positron mission tomography in patients with bladder cancer 总被引:5,自引:1,他引:4
Shigeru Kosuda Paul V. Kison Robert Greenough H. Barton Grossman Richard L. Wahl 《European journal of nuclear medicine and molecular imaging》1997,24(6):615-620
The purpose of this study was to assess the feasibility of imaging of bladder cancer with fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) scanning. We studied 12 patients with histologically proven bladder cancer who had undergone surgical procedures and/or radiotherapy. Retrograde irrigation of the urinary bladder with 1000–3710 ml saline was performed during nine of the studies. Dynamic and static PET images were obtained, and standardized uptake value images were reconstructed. FDG-PET scanning was true-positive in eight patients (66.7%), but false-negative in four (33.3%). Of 20 organs with tumor mass lesions confirmed pathologically or clinically, 16 (80%) were detected by FDG-PET scanning. FDG-PET scanning detected all of 17 distant metastatic lesions and two of three proven regional lymph node metastases. FDG-PET was also capable of differentiating viable recurrent bladder cancer from radiation-induced alterations in two patients. In conclusion, these preliminary data indicate the feasibility of FDG-PET imaging in patients with bladder cancer, although a major remaining pitfall is intense FDG accumulation in the urine.
Present address: Department of Radiology, National Defense Medical College, 3-2 Namiki, Tokorozawa 359, Japan 相似文献
93.
M Fujita H Egawa T Miyamoto J Nakano J Matsumoto 《European journal of medicinal chemistry》1996,31(12):981-988
Diethyl 1-cyclopropyl-5,7,8-trifluoro-1,4-dihydro-4-oxoquinoline-3,6-dicarboxylate 4 as a key-intermediate was synthesized via the Dieckmann reaction. The reaction of 4 with nucleophiles proceeded regioselectively at C-5. Facile cyclization between the C-5 and C-6 side chains of the resulting products gave novel pyrroloquinolones 10 and 12 and pyrazoloquinolones 15. They were converted into a series of cyclic amino-substituted pyrroloquinolones 17–21 and pyrazoloquinolones 22–24, and their in vitro antibacterial activities were tested. 1H-Pyrrolo[2,3-f]quinolone 17a and 2H-pyrrolo[3,4-f]quinolone 21a exhibited a potent in vitro antibacterial activity. 相似文献
94.
Fluorine-18-fluorodeoxyglucose positron emission tomography for preoperative parathyroid imaging in primary hyperparathyroidism 总被引:5,自引:3,他引:2
Pierre Melon Andre Luxen Etienne Hamoir Michel Meurisse 《European journal of nuclear medicine and molecular imaging》1995,22(6):556-558
Fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) imaging was performed in seven consecutive patients with primary hyperparathyroidism to preoperatively locate parathyroid adenomas. Foci of FDG accumulation corresponding to abnormal parathyroid tissue were observed in two out of nine surgically excised parathyroid adenomas. It was concluded that FDG PET imaging demonstrated a too low sensitivity for systematic preoperative detection and localization of parathyroid glands causing primary hyperparathyroidism. 相似文献
95.
96.
目的探讨PET-CT一体机在恶性肿瘤中的应用价值.方法收集已经明确诊断的全身不同部位的恶性肿瘤病例62例,经PET-CT检查后进行回顾性分析,采用目测和半定量分析方法.结果62例肿瘤病人共检出142个病灶,PET图像阳性率93.55%(58/62);PET图像阴性率6.45%(4/62);PET发现病灶而CT未完全发现病灶率19.4%(12/62);CT发现而PET未见浓聚率6.45%(4/62);原发灶未能找到率1.61%(1/62).标准化摄取值(SUV)大于2.5占78.2%(111/142);SUV2.5~2.0占14.8%(21/142);SUV小于2.0占7%(10/142).结论PET-CT与单纯PET,CT比较具有明显的优势,可以精确定位、定性,但PET-CT也有一定的局限性. 相似文献
97.
《Journal of labelled compounds & radiopharmaceuticals》2003,46(8):699-713
The first application of a Sonogashira cross‐coupling reaction in 18F chemistry has been developed. The reaction was exemplified by the cross‐coupling of terminal alkynes (ethynylcyclopentyl carbinol 6 , 17α‐ethynyl‐3,17β‐estradiol 7 and 17α‐ethynyl‐3‐methoxy‐3,17β‐estradiol 8 ) with 4‐[18F]fluoroiodobenzene. 4,4′‐Diiododiaryliodonium salts were used as precursors for the synthesis of 4‐[18F]fluoroiodobenzene, enabling the convenient access to 4‐[18F]fluoroiodobenzene in 13–70% yield using conventional heating or microwave activation. The Sonogashira cross‐coupling of 4‐[18F]fluoroiodobenzene with terminal alkynes gave the corresponding 4‐[18F]fluorophenylethynyl‐substituted compounds [18F]‐9 , [18F]‐10 and [18F]‐13 in yields up to 88% within 20 min of starting from 4‐[18F]fluoroiodobenzene. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
98.
Desipramine (DMI, 15 mg/kg, s.c.) decreased [3H]CGP-12177-labelled cortical β-adrenoceptor density (Bmax) by 30% upon chronic (14 day) treatment. However, even a single dose (in mg/kg) of DMI (15) or the β-adrenoceptor agonist, clenbuterol (20), induced a rapid (24 hour) and significant reduction of β-adrenoceptor Bmax (−15%; p<0.01). Acute treatment with amitryptiline (10), clorgyline (1), fluoxetine (10), nomifensine (10) or maprotiline (20) had no significant effect on [3H]CGP-12177-labelled β-adrenoceptors, suggesting that rapid down-regulation may not be a general property of antidepressant drugs. None of the antidepressants altered the Bmax of [3H]ketanserin-labelled 5-HT2A receptors on acute treatment. These results show that β-adrenoceptor down-regulation by clenbuterol and DMI is not dependent on chronic treatment and may, therefore, be a poor correlate of the gradual onset of therapeutic efficacy seen clinically with antidepressant drugs. 相似文献
99.
1. The effect of strophanthidin on the slow inward current (Isi) and on contractile force were studied in guinea-pig isolated ventricular myocytes and intact papillary muscles, respectively. In myocytes, both low (10 nmol/L) and high (1-10 mumols/L) concentrations had small or no effects in either direction on Isi whereas norepinephrine (10-100 nmol/L) increased it. To determine whether the same results are obtained after decreasing or increasing intracellular calcium or sodium, the same concentrations of strophanthidin were tested in different procedures that are known to (i) increase [Ca]i and decrease [Na]i (high [Ca]o, 3.6-5.4 mmol/L; low [Na]o, 112 mmol/L; (ii) decrease [Ca]i and increase [Na]i (low [Ca]o, 0.45-1 mmol/L; Sr, 1 mmol/L; (iii) decrease [Ca]i and [Na]i (Cd, 0.1-0.2 mmol/L); and (iv) increase [Ca]i and [Na]i (veratridine, 0.2 mumol/L). High [Ca]o and veratridine increased whereas low [Ca]o and Cd decreased Isi. In contrast, during these various procedures, strophanthidin had small and inconsistent effects at a low or high concentration. In intact papillary muscles, low strophanthidin decreased whereas high strophanthidin increased contractile force. It is concluded that strophanthidin has little direct or indirect effect on Isi and that the decrease in force by low and increase in force by high concentrations in intact muscle are probably related to demonstrated decrease and increase, respectively, in intracellular sodium activity. 相似文献
100.
K. Hatayama J. Kambayashi T. Kawasaki K. Morimoto T. Ohshiro T. Mori 《Thrombosis research》1986,41(6):761-770
The interrelationship between ATP-secretion, protein phosphorylation and intracellular Ca2+ concentration ([Ca2+]i) was studied in both 32P and quin 2 loaded human platelets stimulated by thrombin or thromboxane A2 analogue (STA2). In platelets stimulated by thrombin, the degree of 47,000 dalton polypeptides (P47) phosphorylation was observed in completely dose-related manner, regardless of the amount of [Ca2+]i. In the same condition, the degree of myosin light chain (P20) phosphorylation, however, was well correlated with ATP secretion and [Ca2+]i, when platelets were stimulated by lower dose of thrombin. The similar results were obtained in platelets stimulated by STA2. These findings suggested that P20, but not P47, phosphorylation in activated platelets is mediated by a rise of [Ca2+]i and is well correlated with the secretory reaction. It was unlikely that P47 phosphorylation plays any role in promoting platelet activation. 相似文献