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101.
目的:探讨气管切开与呼吸机机械通气抢救重度有机磷农药中毒(AOPP)致呼吸肌麻痹的疗效。方法:对6例重度AOPP致呼吸肌麻痹患者在综合治疗基础上,及时予气管切开,并使用全能呼吸机机械通气。结果:治愈5例,死亡1例。抢救成功率达83.3%。结论:对重度AOPP患者及时行气管切开,并使用全能呼吸机机械通气,抢救效果良好。 相似文献
102.
R. Lemmens-Gruber H. Marei P. Heistracher 《Naunyn-Schmiedeberg's archives of pharmacology》1997,355(2):230-238
GE 68 ((Rac.)-1-[3-(Phenylethyl)-2-benzofuryl]-2-(propylamino)-ethanol hydrochloride) is structurally related to propafenone,
and exerts negative inotropic and negative chronotropic effects similar to the parent drug, but lacks any β-adrenoceptor blocking
activity contrary to propafenone. Thus, the electrophysiological effects of GE 68 were studied in papillary muscles, left
atria, Purkinje fibres, sinoatrial nodes and ventricular myocytes of the guinea-pig heart with the intracellular microelectrode
technique and the patch-clamp technique in the cell-attached mode.
The decrease of the maximum upstroke velocity (V˙max) by GE 68 (1 to 10 μM) was use- and frequency-dependent. V˙max recovered from the use-dependent block with a time constant of 4.1 ± 0.6 s. In papillary muscles and Purkinje fibres action
potential duration was shortened, while it was prolonged in left atria and sinoatrial nodes. Half-maximal steady-state inactivation
of the sodium channels was shifted to more negative membrane potentials (control: –91.5 ± 0.8 mV, 10 μM GE 68: –97.9 ± 2.5 mV).
The peak of the current-voltage relationship and the reversal potential were not changed by GE 68. The amplitude of the unitary
current remained unaltered, while open state probability was decreased. The most striking effect of GE 68 was an increase
of the number of sweeps without single channel openings (1 μM: 2 fold, 10 μM: 6 fold). GE 68 also caused a decrease of the
mean open times, and an increase of the mean closed times in unmodified and pronase-modified sodium channels.
Besides the lack of β-adrenoceptor blocking activity, data present a faster recovery from the use-dependent block by GE 68
and a lower affinity to inactivated sodium channels compared to the reference drug propafenone, as well as differences in
the effect on single channel kinetics.
Received: 25 July 1996 / Accepted: 14 October 1996 相似文献
103.
Effective segmental chemoembolization of advanced hepatocellular carcinoma with tumor thrombus in the portal vein 总被引:12,自引:0,他引:12
Tetsuya Katsumori M.D. Masato Fujita Takeshi Takahashi Osamu Satoh Shigeki Ichijima Toshiyuki Nakamura Hiroyuki Morishita Kohji Ohno Yasuhiko Nakano Tomoho Maeda 《Cardiovascular and interventional radiology》1995,18(4):217-221
Purpose: Evaluate therapeutic results of transcatheter segmental hepatic artery chemo-oily-embolization (segmental TAE) against advanced hepatocellular carcinomas (HCC) accompanied by portal tumor thrombus (PTT).
Methods: Segmental TAE was performed in nine patients with hepatic cirrhosis and advanced HCCs accompanied by PTT. Four subsegmental portal branches were obstructed by PTT in three patients, and two were obstructed in the remaining six patients. TAE was performed into the targeted segmental hepatic artery followed by embolization with gelatin sponge particles.
Results: In one patient undergoing subsequent resection, a marked anticancer effect on the PTT was demonstrated histologically. In the eight other patients who did not undergo subsequent resection, the cumulative survival rates were 67% at 6 months, 44% at 1 year, and 22% at 2 years. No serious complications were noted.
Conclusions: This therapeutic approach is thought to be a useful treatment for HCC with PTT, because it reinforces anticancer effects and can be performed more safely than conventional transcatheter arterial embolization. 相似文献
104.
S. Sunano T. Shimada K. Moriyama K. Shimamura 《Clinical and experimental pharmacology & physiology》1990,17(6):413-425
1. The time courses of the relaxation, induced by removal of extracellular Ca2+, of K-depolarized mesenteric artery preparations from stroke prone spontaneously hypertensive rats (SHRSP) and Wistar-Kyoto rats (WKY) were compared. 2. The time course of the decline in extracellular Ca2+ was estimated from the time course of the relaxation and the concentration-response curve of K(+)-depolarized preparations to Ca2+. The time course of the decline in the intracellular free Ca2+ concentration was also estimated from the reported relation between Ca2+ concentration and the contraction of skinned vascular smooth muscle. 3. The time course of relaxation was exponential, the curve being made up of three components. The time course was slower in preparations from SHRSP, especially the first component of the relaxation curve. 4. The time courses of the decline in the intracellular and extracellular Ca2+ concentrations were also exponential, being made up of three components and were also slower in the preparation made from SHRSP. 5. The wall and muscle layer of the mesenteric arteries used in the present experiments were significantly thicker in the SHRSP preparations. 6. Calculation of the half relaxation time, based on the diffusion of Ca2+ across the blood vessel wall, suggested that the slower relaxation in preparations from SHRSP is due largely to the thicker muscle layer, although differences in Ca2+ sequestration by the smooth muscle cells may also be involved. 相似文献
105.
老年人视网膜中央血管在前部视神经的解剖特征 总被引:1,自引:0,他引:1
目的:观察老年人前部视神经视网膜中央血管的解剖特征。
方法:通过组织连续切片和计算机影像分析,观察60~82岁老年人的18只眼球标本中无解剖变异的视网膜中央动脉(CRA)15条,视网膜中央静脉(CRV)23条在筛板前、筛板区及筛板后的管径变化。
结果:老年人筛板前、筛板区、筛板后CRA平均面积的均值分别为(12.70,17.40,18.00)×10-3mm2;平均周长的均值分别为0.56,0.56,0.57mm,平均周长之间相比无显著差异。CRV平均面积的均值分别为(7.00,5.40,7.90)×10-3mm2;平均周长的均值分别为0.44,0.38,0.41mm;CRV平均周长筛板前与筛板区相比,筛板区与筛板后相比均有显著差异。
结论:老年人CRA眼球内外管径一致;CRV在筛板区管径最小。
(中华眼底病杂志,1997,13:213-214) 相似文献
106.
Eiji Takeuchi Yuji Nimura Shin-ichi Mizuno Hideaki Suzuki Shinsuke Iyomasa Masaki Terasaki Hiroshi Kuriki Keiko Tamiya-Koizumi Shonen Yoshida 《Journal of Hepato-Biliary-Pancreatic Surgery》1997,4(3):254-262
Hepatocyte regeneration has been widely investigated, with the mitotic index and the incorporation of [3H]thymidine being used as regeneration markers. We focused on the induction of DNA replication enzymes, particularly DNA polymerases
(pol) α, δ, and ε. Using rat models, we have shown that the activity of pol α in crude liver extract well represents the regenerating
capacity of hepatocytes. Using pol α as an indicator, we analyzed liver regeneration in rat models under various conditions:
obstructive jaundice, external or internal biliary drainage, and the obstruction of portal vein branches. It has been revealed
that the ligation of the common bile duct alone induces a certain amount of hepatocyte proliferation. It was striking that
external biliary drainage suppressed regeneration capacity in cholestatic rat liver after partial hepatectomy. The strong
regeneration in nonligated lobes induced by portal branch ligation was similar to the liver regeneration seen after partial
hepatectomy with respect to the induction of DNA polymerases. Taken together, the aspects of DNA replication, particularly
the induction of DNA polymerases, may contribute to shedding new light on the regeneration of human liver.
This work was supported in part by a Grant-in-Aid for General Scientific Research and for Cancer Research from the Ministry
of Education, Science and Culture, Japan, and by grants from the Uehara Memorial Foundation 相似文献
107.
Murali Pagala N. V. Nandakumar S. A. T. Venkatachari Kadirimangalam Ravindran Bellamakonda Amaladevi Tatsuji Namba David Grob 《Muscle & nerve》1993,16(9):911-921
Fatigue mechanisms in normal intercostal muscle and muscle from patients with myasthenia gravis (MG) were evaluated by monitoring the compound muscle action potential (CMAP) and tetanic tension responses to repetitive nerve or muscle stimulation in vitro. When fatigue was induced by nerve stimulation at 30 Hz for 0.5 s every 2.5 s, about half of the original tension decreased after 30 min in normal muscle and 5 min in MG muscle. Analysis of the changes in area of CMAPs and tension indicated that impairment of neuromuscular transmission, muscle membrane excitation, and excitation-contraction (E-C) coupling and contractility accounted for 40%, 29%, and 31% of fatigue in normal muscle, and 83%, 0%, and 17% of fatigue in MG muscle. When fatigue was induced by muscle stimulation at 30 Hz, tension declined by a quarter after 30 min in normal muscle, but by a half after 17 min in MG muscle. Impairment of muscle membrane excitation and E-C coupling and contractility accounted for 58% and 42% of fatigue in normal muscle, and 22% and 78% of fatigue in MG muscle. Thus, fatigue of normal muscle is caused by impairment of at least four processes, and enhanced fatigue of MG muscle is caused by greater impairment of neuromuscular transmission, E-C coupling, and contractility. © 1993 John Wiley & Sons, Inc. 相似文献
108.
Ryo Suzuki M.D. Shunsaku Kobayashi 《Documenta ophthalmologica. Advances in ophthalmology》1988,70(4):293-300
Using tension-recording methods, we compared the effects of acetylcholine (Ach) and carbachol on the bovine iris sphincter. The isolated muscle strips were mounted in a 0.2 ml organ bath, through which Krebs solution at 36 °C flowed continuously. There was a tenthousandfold difference in potency between carbachol and Ach in this tissue. Neostigmine or eserine, acetylcholinesterase (AchE) inhibitors, produced a larger contraction of the muscle than did Ach. Ach-induced contractions were potentiated by low doses of anti-AchEs and were inhibited by atropine.This in vitro study suggests that Ach and/or endogenous chemical agents may be spontaneously released from tissues and that AchE activities in this tissue strongly inhibit or mask the Ach action, probably in order to protect the nerve terminals from released Ach. 相似文献
109.
Yaping Deng huashang Zhou Junguo DuanDepartment of Ophthalmology the Teaching Hospital of Chengdu College of TCM Chengdu China 《眼科学报》1994,(1)
Twenty five cases, including 26 eyes with retinal vein occlusion (RVO) were examined by means of the electro-oculogram. The results showed that 23 of the 26 eyes suffering from RVO exhibited abnormalities of the electro-oculogram (EOG). The potential difference and Arden ratio in the RVO eyes were lower than those in the normal eyes (P<0.01). The more the visual acuity of ill eyes was decreased, the higher the abnormal rate of EOG in ill eyes was. 14 eyes had the visual acuity less than 0.1, whose EOGs were abnortmal. Six eyes had the visual acuity from 0. 2 to 0. 4, in which the EOGs of 5 eyes were abnormal. Six eyes had the visual acuity more than 0. 5, a-mong which the EOGs of 4 eyes were abnormal. Based on the above observations, it may be considered that the circulatory disturbance resulting from RVO damages not only the internal layer but also the external layer of the retina. We suggest that EOG is a useful method for distingquishing lesions caused by RVO and may reflect the functional condition 相似文献
110.
报告应闭合式玻璃体切除术治疗7例(7眼)因视网膜静脉阻塞所致的玻璃体出血。所有病人术后眼底清晰可见,视力明显提高。术后4例出现再出血,经药物治疗后出血吸收,加用氩离子激光视网膜光凝,无再出血。随访3至18个月所有病人无新生血管性青光眼及牵引性视网膜脱离出现。认为玻璃体切除术不但能使屈光间质恢复透明,视力提高,预防牵引性视网膜脱离,而且为明确诊断和进一步激光治疗提供条件。 相似文献