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1.
《Pathology, research and practice》2020,216(6):152991
Perivascular epithelioid cell tumor (PEComa) is a rare mesenchymal tumor originating from perivascular epitheloid cells showing melanocytic and smooth muscle differentiation. The uterus represents the second most common site of origin. A 49 years woman presented to our Hospital for a vaginal spontaneous expulsion of a mass suggestive for malignant mesenchymal tumor. The patient underwent total hysterectomy and bilateral salpingo-oophorectomy and the histopathological report was compliant with a PEComa with aggressive behavior. Medical Literature databases about PEComa were searched. The current literature identified near 90 cases of uterine PEComas and they are categorized as uncertain malignant potential or with aggressive behavior. Primary surgical excision represents the gold-standard treatment. Recently targeted therapy with mTOR inhibitors has been introduced with an important beneficial. In this paper we review the Literature about the uPEComa with aggressive behavior reporting the first case of spontaneous vaginal expulsion. 相似文献
2.
Is colonic electrical activity a similar phenomena to small-bowel electrical activity? 总被引:4,自引:0,他引:4
Dr. José A. S. Medeiros M.D. Ph.D. Fausto A. Pontes M.D. Ph.D. Octávio A. R. O. Mesquita 《Diseases of the colon and rectum》1997,40(1):93-99
PURPOSE: This study was designed to investigate colonic spike bursts regarding 1) their migration behavior, 2) their pressure correlates, and 3) comparing colonic short spike bursts with spike bursts from migrating myoelectric complex from the small bowel. METHODS: Rectosigmoid electromyography and manometry were recorded simultaneously in seven normal volunteers and electromyography alone in five others during two hours of fasting and for two hours after one 2,100-kJ meal. One patient with an ileostomy was also studied by the same method to record the migrating myoelectric complex from the terminal ileum during fasting. RESULTS: Three kinds of spike bursts were observed in the pelvic colon: rhythmic short spike bursts, migrating long spike bursts, and nonmigrating long spike bursts. The meal significantly increased the number of migrating and nonmigrating long spike bursts (from 25 to 38.7 percent of the recording time;
P
<0.01). These bursts of potentials showed a peak 15 minutes after the meal, which may be caused by the gastrocolic reflex. Migrating long spike bursts started anywhere along the rectosigmoid and migrated from there aborad 82 percent of the time and orad or in both directions in 10 or 7 percent of the time, respectively. They originated pressure waves 99 percent of the time. Short spike bursts were more frequent before the meal (15.1 percent before and 9.6 percent after the meal), but the difference was not significant; they neither propagated nor initiated pressure waves detected by the miniballoon. CONCLUSIONS: Migrating long spike bursts were the only potentials that migrated, sometimes for short distances. Short spike bursts are a different phenomenon from the small-bowel migrating myoelectric complex because they do not migrate; they can occur during the postprandial period and never originated intraluminal pressure waves.Supported by a grant from the Instituto Nacional de Investigação Científica, Proc. DBI-22086.Presented at the meeting of the Portuguese Congress of Gastrenterology, Vila Moura, Portugal, June 2 to 5, 1993. 相似文献
3.
目的 评价子宫动脉栓塞术治疗子宫肌瘤的近期疗效。方法 89例子宫肌瘤患者,采用Seldinger技术分别作左右子宫动脉主干插管检查和栓塞治疗,栓塞剂采用聚乙稀醇颗粒(PVA)或白芨混合颗粒。结果 72例(80.9%)完成随访,随访时间1~28个月。有94.1%(64/68)的患者月经复常;治疗后瘤体缩小25.2%~76.8%(M=41.3%)。除了术中术后疼痛(65例)和发热(16例)外,有2例因肌瘤坏死行子宫切除术,1例出现卵巢早衰。结论 子宫动脉栓塞术治疗子宫肌瘤的近期疗效满意,远期疗效尚待进一步观察。 相似文献
4.
Minzhong Yu Lezheng Wu Dezheng Wu 《Documenta ophthalmologica. Advances in ophthalmology》1990,76(1):37-46
The visual pursuit test is a method that collects and analyzes the characteristics of pursuit eye movements and examines the function of the eye movement system. This paper analyzes the model parameters of the smooth pursuit eye movement system in order to explore a method for improving the analysis. The input-output relationship of the smooth pursuit system can be expressed by a quasilinear model. We compute the model parameters (gain, phase, spectral purity, cross covariance) by digital signal processing. Eye movement is recorded by electrooculogram. Both eyes are tested individually. The visual target moves at frequencies of 0.2, 0.4, 0.8, 1.2, and 1.6 Hz. Ranges are gain, 1.01 to 0.70; phase, -0.1 ° to -66 °; spectral purity, 0.97 to 0.70; and cross covariance, 0.99 to 0.26. We tested 40 normal subjects as well as patients with ataxia (8), vertigo (18), and ophthalmoplegia (9). The oculomotor system of normal subjects functions as a linear system in the performance of this test at 0.2 to 0.8 Hz. The spectral purity dropped to about 0.70 at 1.6 Hz. The variability of all measures increases greatly at 1.6 Hz, which indicates that this target motion exceeds the tracking ability of many normal subjects and that the oculomotor system of normal subjects functions as a nonlinear system in this condition. Statistical tests show no significant differences between sex, age, and the two eyes. The model parameters tentatively proved effective in clinical application. 相似文献
5.
细胞内钙信号的变化调节血管平滑肌细胞增殖 总被引:4,自引:0,他引:4
目的探讨细胞内钙信号的变化对大鼠血管平滑肌细胞(VSMC)增殖作用的影响及其对细胞内信号转导机制的变化。方法以培养的大鼠VSMC为模型,用雷尼丁(RY)剌激VSMC内贮Ca2 释放入胞浆,用3H亮氨酸及3H胸腺嘧啶掺入量作为反应VSMC增殖的指标,加入不同的细胞内信号转导阻断剂,观察对RY效应的影响。结果与对照组相比,RY浓度依赖性地促进细胞内游离钙浓度的增高,差异显著(P<0.05或0.01)。RY剌激组蛋白核酸合成速率明显增高,与对照组相比差异显著(P<0.01);尼卡地平(Nicardipine),蛋白激酶C抑制剂(H7),钙调素激酶(CaMPK)抑制剂(W7)和丝裂素活化蛋白激酶(MAPK)抑制剂(PD98059)能明显抑制RY介导的VSMC蛋白核酸合成速率增高,与RY剌激组相比差异显著(P<0.01)。结论细胞内钙信号的变化明显促进VSMC增殖,但其效应可能通过Ca2 、PKC、MAPK来介导。钙离子拮抗剂可抑制血管平滑肌细胞增殖。 相似文献
6.
Twenty obsessive-compulsive disorder patients and comparison samples of 20 schizophrenia and 20 nonpsychiatric individuals were presented with (a) a step-ramp task designed to measure smooth pursuit initiation and (b) a regular ramp task designed to measure steady-stale tracking performance. Obsessive-compulsive disorder and non-psychiatric individuals had statistically similar pursuit reaction time and average eye accelerations during the open-loop interval. They also had similar closed-loop performance. Schizophrenia patients, however, had delayed pursuit reaction times and reduced eye acceleration during the last 60 ms of the open-loop interval. These findings suggest that brain regions supporting smooth pursuit performance are unimpaired among obsessive-compulsive disorder patients. Furthermore, the deficits found in the schizophrenia patients replicate and extend the results of previous smooth pursuit studies. 相似文献
7.
过氧化氢对血管平滑肌细胞的作用 总被引:5,自引:2,他引:3
目的 研究过氧化氢 (H2 O2 )对兔血管平滑肌细胞的作用机制。方法 兔血管平滑肌细胞 (VSMCs)原代培养 ,微量细胞培养四甲基偶氮唑蓝法 (MTT)检测不同浓度H2 O2 在不同时段对其增殖影响 ,确定进一步研究的H2 O2 浓度 ,并应用流式细胞仪检测此浓度H2 O2 对VSMCs细胞周期和细胞凋亡的作用。结果 MTT法检测 ,H2 O2 浓度≥ 10 0 μmol/L(10 0~ 14 0 0 μmol/L)时 ,与VSMCs作用仅 1h ,即出现吸光度值显著降低 (P <0 .0 1) ;流式细胞仪细胞周期检测 ,H2 O2 浓度≥ 10 0 μmol/L时 ,与VSMCs作用 2 4h后 ,其G1期细胞数显著高于对照组 (94.65 %和 79.97% ) (P <0 .0 1) ,以H2 O2浓度在 10 0 μmol/L时尤为明显 ;流式细胞仪AnnexinV PI双标细胞凋亡检测 ,10 0 μmol/LH2 O2 有促进VSMCs凋亡作用 ,并在作用 48h左右达到高峰 ,占 2 6.76% ,与对照组相比 ,差异有显著性 (P <0 .0 1)。结论 H2 O2 浓度≥ 10 0 μmol/L时 ,可显著抑制VSMCs增殖 ;当H2 O2 浓度为 10 0 μmol/L时 ,有促进VSMCs凋亡作用。 相似文献
8.
9.
A. J. Bullock R. A. Duquette N. Buttell S. Wray 《Pflügers Archiv : European journal of physiology》1998,435(4):575-577
Intracellular pH (pHi) is known to modulate contraction. Neonatal tissues can differ from adult tissue in contractile response to stimuli known
to alter pHi e.g. hypoxia. Changes of pH are attenuated by buffering, thus any difference in buffering power (β) between tissues could
affect their functional response to pHi perturbation. Similarly the extent to which any extracellular pH (pHo) alteration is transmitted into a pHi change will also influence function. We have therefore determined the intrinsic β and effect of pHo change on pHi in neonatal and adult ureteric, uterine and gastric smooth muscles using the pH-sensitive fluorophore carboxy-SNARF. β was
found to be similar in the three adult tissues, but there were significant differences between neonatal tissues. In contrast,
we found little difference in the amount of pHi change produced by pHo change between neonatal and adult tissues from the same smooth muscle, but a difference between smooth muscles. These data
highlight significant differences between smooth muscles and their developmental state, which may contribute to different
degrees of protection when pH is perturbed.
Received: 17 October 1997 / Received after revision: 27 November 1997 / Accepted: 28 November 1997 相似文献
10.
Viktoria Werkström Lars Ny Katarina Persson K.-E. Andersson 《Naunyn-Schmiedeberg's archives of pharmacology》1997,356(2):151-158
Neuronal regulation of smooth muscle tone in the female pig urethra has mainly been studied in vitro using electrical field
stimulation (EFS) of nerves. Excitatory control is considered to be exerted by released noradrenaline, whereas inhibitory
control is non-adrenergic non-cholinergic (NANC), and mediated by nitric oxide (NO), and an as yet unidentified agent. We
investigated the functional and morphological effects of α-latrotoxin (αLTX), a spider neurotoxin believed to cause massive
release of vesicle-stored neurotransmitters, on spontaneously developed urethral smooth muscle tone. The effects were compared
to those of EFS and high potassium. In the presence of the NO-synthesis inhibitor Nω-nitro-L-arginine (L-NOARG: 0.3 mM) both αLTX and EFS evoked contractions. After treatment with scopolamine and phentolamine,
no contraction was observed, and under these conditions αLTX and EFS induced relaxation. At low frequencies (<12 Hz), the
EFS-induced relaxations were rapid, whereas at higher frequencies (>12 Hz), they were biphasic, consisting of a rapid first
phase followed by a more long-lasting second phase. L-NOARG abolished the relaxations at low frequencies, as well as the first
phase of the biphasic relaxation. The second phase was not affected by treatment with L-NOARG, but 0.1 μM ω-conotoxin GVIA,
blocker of N-type voltage-operated calcium- channels (VOCCs), markedly reduced or abolished the response. In the presence
of L-NOARG or ω-conotoxin GVIA, the αLTX-induced relaxation was significantly decreased, and the combination of L-NOARG and
ω-conotoxin GVIA further reduced or abolished the relaxation. In preparationstreated with tetrodotoxin or scorpion venom,
believed to inactivate nerves by acting on sodium channels, αLTX and EFS had no effects. αLTX-induced relaxation was not associated
with changes in cyclic GMP or cyclic AMP content. High (80 mM) potassium solution induced a triphasic response of the preparation.
A transient relaxation was followed by a restoration of tone, and then by a persistent relaxation. The persistent relaxation
was slightly reduced by scorpion venom or L-NOARG, but reduced by 50% by a combination of L-NOARG and ω-conotoxin GVIA. Ultrastructural
analysis of the urethral circular smooth muscle layer revealed a moderate amount of nerve profiles supplying the smooth muscle.
In control preparations, the nerve profiles contained both small synaptic vesicles and large dense core vesicles. αLTX caused
a major loss of both types of vesicle. The present data suggest that αLTX has the ability to release not only adrenergic and
cholinergic transmitters, but also NANC mediators of relaxation, including NO, from nerve terminals in the urethra.
Received: 13 January 1997 / Accepted: 17 April 1997 相似文献