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11.
AIM:To examine the possible role of agents elevating cAMP to release NO from aortic en-dothelial cells. METHODS:NG-nitro-L-arg inine methylester (L-NAME) , an inhibitor of NO synthase, partially inhibited endothelium-dependent relaxation evoked in phenylephrine-precontracted rings by isoproterenol and abolished relaxation mediated by forskolin 0. 2 umol L-1.RESULTS: In rings without en-dothelium, isoproterenol and forskolin were less effective relaxants and L-NAME had no effect on the responses. In methylene blue-treated rings isoproterenol- and forskolin-induced relaxation were prevented in both en-dothelium-intact and -denuded rings, but the inhibitory effects of methylene blue were significantly more in rings with endothelium than in those without. On the other hand, relaxation induced by sodium nitroprusside was not inhibited by L-NAME, but was inhibited by methylene blue in both the endothelium-intact and -denuded rings. The concentration relaxation curves to sodium nitroprusside after methylene bl 相似文献
12.
目的:观察复方亚甲蓝长效止痛剂用于肛肠科手术后止痛的疗效及时机。方法将448例需在硬膜外麻醉下行肛肠手术治疗患者,随机分为A、B、C、D 4组。 A、C组选择传统镇痛麻醉,B、D组选择超前平衡镇痛麻醉;A、B组术中采用利多卡因、盐酸布比卡因、地塞米松联合麻醉;C、D组给予甲磺酸罗哌卡因、利多卡因、0.9%氯化钠液、地塞米松、2%亚甲蓝等制成复方亚甲蓝长效止痛剂进行麻醉。比较各组患者术后各时期疼痛视觉模拟评分( VAS)及麻醉后并发症。结果 D组麻醉术后各时期VAS评分低于C组和B组,A组麻醉术后各时期VAS评分高于C组,差异均有统计学意义(P<0.05)。 D组麻醉后并发症发生率低于C组和B组,A组麻醉后并发症发生率高于C组,差异均有统计学意义( P<0.05)。结论超前平衡镇痛联合复方亚甲蓝长效止痛剂在肛肠科手术中具有良好的镇痛效果,并且麻醉后并发症发生率较低。 相似文献
13.
阐明ONO-1078(ONO,4-氧-8-[对-(4-苯丁氧基)苯甲酰氨基]-2-(5-四唑基)-4H-1-苯并毗喃)对神经原性刺激诱导心血管反应的作用.方法:观察豚鼠心房和心室伊文思蓝渗出以及平均主动脉压(MAP)变化.结果:在阿托品(1 mg·kg~(-1),iv)预先处理后,电刺激迷走神经(ESV,10 Hz,5 ms,2或10 V,90 s)显著增高伊文思蓝渗出;辣椒素和P物质也增加染料渗出并降低平均动脉压(MAP).ONO(0.03,0.1 mg·kg~(-1),iv)抑制ESV的反应,在刺激强度低(2 V)时更明显;ONO 0.03 mg·kg~(-1)减弱辣椒素引起的微血管渗漏和低血压,但对P物质无影响.结论:ONO-1078可能通过抑制感觉神经肽释放而调节神经原性炎症时的心血管反应. 相似文献
14.
早期胃癌前哨淋巴结微转移临床分析 总被引:2,自引:1,他引:2
目的探讨亚甲蓝示踪法前哨淋巴结(SLN)活检术在早期胃癌外科诊疗中的临床意义。方法 39例早期胃癌患者,术中用亚甲蓝示踪SLN,对SLN及所有术后胃周淋巴结进行HE染色,对SLN进一步行细胞角蛋白20(CK20)的免疫组化染色(IHC)及逆转录聚合酶链反应(RT-PCR)检测。比较3种检测方法对SLN转移灶检出的差异。结果 39例患者中,亚甲蓝示踪成功检出37例,检出成功率达94.5%。IHC与RT-PCR微转移检出率均为18.9%。由SLN状态预测胃周淋巴结转移情况:HE切片病检组前哨淋巴结检测准确率97.3%(36/37),假阴性率为16.7%(1/6);CK-20行IHC及RT-PCR组检测准确率97.3%(36/37),假阴性率为14.3%(1/7)。结论亚甲蓝示踪法能有效检出早期胃癌SLN。HE染色结合IHC及RT-PCR检测能提高SLN中微转移的检出率。 相似文献
15.
Summary In this study we employed retrograde axonal transport of (E)-2,2-vinylendi-benzofuran-5-carboxamidin-diaceturate or true blue (TB) to study the peripheral autonomic innervation of the canine nasal mucosa. After injection of TB into the nasal mucosa, labeled neurons were found in the ipsilateral sphenopalatine ganglion (SPG) and the superior cervical ganglion (SCG). There were no labeled neurons in the middle cervical or stellate ganglia. This indicated that the origin of the postganglionic sympathetic fibers of the nasal mucosa was only from the ipsilateral SCG. When TB was injected into the nasal mucosa of dogs following a caudal or ethmoidal neurectomy, labeled neurons could still be found in the SPG and SCG. When TB was injected into the nasal mucosa of dogs following ethmoidal and vidian neurectomies or with maxillary neurectomy added, some labeled neurons could still be found in both the ipsilateral SPG and SCG. These results support the concept that another pathway — perhaps perivascular — exists for postganglionic sympathetic fibers other than the vidian and ethmoidal nerves. Labeled neurons were still observed in SPG when TB was applied to the canine nasal mucosa following neurectomy of either the ethmoidal or the caudal nasal nerve. However, retrograde labeled neurons could not be found in SPG following simultaneous neurectomies of the ethmoidal and caudal nasal nerves. These results show that the postganglionic parasympathetic fibers originating in the SPG travel along the ethmoidal and caudal nasal nerves.Presented at Tenth Midwinter Meeting of the Association for Research in Otolaryngology, Clearwater Beach, Florida, 3 February 1987 相似文献
16.
Geoffrey Pollack MD Aron Pollack MS Joel Delfiner MD John Fernandez MD 《The Laryngoscope》2009,119(10):1941-1946
Methylene blue has been used to help facilitate parathyroid surgery for over 30 years. Its use has been widely considered both safe and cost effective. Twenty‐six cases of a toxic metabolic encephalopathy, however, have been reported with its use. As a result, some surgeons have stopped using this technique altogether. It is now known that methylene blue is a monoamine oxidase inhibitor. When combined with drugs that increase central serotonin neurotransmission, serotonin toxicity results. This is the cause of the encephalopathy described in the literature. A case report, review of the literature, and guidelines as to its proper use are presented so as to allow for safe parathyroid surgery. Laryngoscope, 2009 相似文献
17.
Sentinel lymph node biopsy (SLNB) has become an accepted standard of care to stage the axilla for clinically node-negative early stage breast cancer. In experienced hands, studies have shown an acceptable rate of identification of the sentinel lymph node (SLN) with blue dye only. Lymphazurin is occasionally associated with severe allergic reaction, including anaphylaxis and death. The use of methylene blue alone as a method of identifying the SLN in breast cancer has been reported once previously in the literature. Methylene blue may be an acceptable alternative with fewer deleterious side effects. Medical records of patients, who underwent sentinel node mapping between September 2003 and March 2005 by two surgeons at an academic medical center were reviewed. SLN mapping was performed by periareolar injection of 5 cc of 1% methylene blue. All patients with positive SLNs underwent completion axillary node dissection. During the study period, 141 consecutive patients with clinically node-negative axillas and without evidence of inflammatory breast cancer underwent SLNB with injection of methylene blue only. A SLN was identified in 136 of 141 patients (96.5%). Thirty-three of 136 SLNs (24%) harbored metastatic disease. No cases of anaphylaxis were noted. In experienced hands, methylene blue alone is a highly sensitive method of detecting SLNs. Avoiding the greater frequency of allergic reactions seen with lymphazurin is an important advantage of methylene blue. 相似文献
18.
Andrew W. Szopa-Comley Christos C. Ioannou 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(23)
To increase their chances of survival, prey often behave unpredictably when escaping from predators. However, the response of predators to, and hence the effectiveness of, such tactics is unknown. We programmed interactive prey to flee from an approaching fish predator (the blue acara, Andinoacara pulcher) using real-time computer vision and two-wheeled robots that controlled the prey’s movements via magnets. This allowed us to manipulate the prey’s initial escape direction and how predictable it was between successive trials with the same individual predator. When repeatedly exposed to predictable prey, the predators adjusted their behavior before the prey even began to escape: prey programmed to escape directly away were approached more rapidly than prey escaping at an acute angle. These faster approach speeds compensated for a longer time needed to capture such prey during the subsequent pursuit phase. By contrast, when attacking unpredictable prey, the predators adopted intermediate approach speeds and were not sensitive to the prey’s escape angle but instead showed greater acceleration during the pursuit. Collectively, these behavioral responses resulted in the prey’s predictability having no net effect on the time taken to capture prey, suggesting that unpredictable escape behavior may be advantageous to prey in fewer circumstances than originally thought. Rather than minimizing capture times, the predators in our study appear to instead adjust their behavior to maintain an adequate level of performance during prey capture.Rapid evasive responses are a vital tool prey use to minimize capture by predators (1, 2). Despite their ubiquity, it can be challenging to demonstrate the benefit of escape strategies, due to the difficulties involved in designing studies which integrate realistic predation with manipulation of prey behavior that experimentally controls for confounding effects. Studying the behavior of real predators is crucial when attempting to demonstrate the adaptive value of prey adaptations, especially when these are dependent on features of predator cognition (3–5). This applies particularly to unpredictable escape behavior by prey, which is thought to enhance prey survival by compromising the ability of predators to anticipate the movement of their target (6). Although unpredictable escape tactics are widespread taxonomically (7, 8), we know little about how real predators respond to unpredictability in prey escape strategies and whether this prevents predators from adjusting their behavior over multiple interactions with prey (9, 10).Controlled experiments in which human predators target continuously moving virtual prey have demonstrated that abrupt and unpredictable changes in direction reduce the accuracy of prey targeting (11, 12). However, it is unknown whether the survival advantage conferred by unpredictable motion also applies against nonhuman predators. Additionally, the escape responses of prey which are initially stationary are common in nature, as numerous prey taxa freeze once they have detected a potential threat or remain motionless to avoid detection by predators, before eventually fleeing only once a predator gets too close (1, 13–15). One way for stationary prey to be unpredictable is to vary the initial escape angle from one encounter to the next (16). This is a distinct tactic to the unpredictable movements made by prey which move continuously regardless of the presence of a predatory threat (6) or the abrupt turns made by some prey in anticipation of a predator’s attack (17). Although theoretical models predict that for a predator of a given speed, prey should select a single optimal escape trajectory which maximizes the distance from an approaching predator (18, 19), predators might anticipate the movements of prey which repeatedly escape at a fixed angle relative to their approach (20). Contrary to expectations based on a single optimal escape path, a wide range of prey species show a substantial degree of variability in their initial escape angles (16), including amphibians (21), crustaceans (22, 23), fish (24–27), insects (28, 29), mammals (30), and reptiles (31). Given that this variability is so widespread taxonomically, investigating whether it represents an antipredator strategy aimed at generating unpredictability could have major implications for our understanding of prey escape behavior (32, 33).Many predator-prey interactions are typified by feedback between the attacker and the target (34), making it difficult to disentangle the effects of prey defenses on predators from the impact of predator behavior on prey using a purely observational approach. One way to determine the importance of prey defensive tactics is to present real predators with standardized virtual prey, whose movements and behavior can be precisely controlled and experimentally manipulated (35–39). However, previous experiments with virtual prey have used unresponsive prey items which do not react to predators, and do not allow the predator to capture prey and be rewarded, making it extremely challenging to study repeated interactions between predators and prey. These limitations can be overcome by using interactive robotic prey (40).To study the effect of unpredictability in prey escape on predators, we developed an experimental system [Fig. 1A; see also Swain et al. (41)], in which artificial robot-controlled prey were programmed to flee from blue acara cichlid (Andinoacara pulcher) predatory fish. Blue acaras are opportunistic predators with a broad diet but actively pursue highly evasive prey such as Trinidadian guppies (Poecilia reticulata) (42, 43). Prey initiated their escape response once the predator had approached within a threshold distance (Fig. 1B), mimicking the tendency of many prey to flee from a distant predator at submaximal speeds (14, 44). After an initial period in which groups of blue acaras were trained to attack the prey (the training period, SI Appendix, SI Methods), individual predators were repeatedly presented with prey which escaped either in predictable or unpredictable directions over 20 successive experimental trials (the test period). For individuals assigned to the predictable treatment (which acted as the control), prey escaped at the same angle relative to the predator’s approach from one trial to the next, whereas in the unpredictable treatment, prey were programmed to flee in random directions over successive trials (Fig. 1C). To successfully capture prey, pursuit predators must respond to changes in prey direction, which occur at the start of a chase (45–47). Across trials with predictable prey, the predators had the opportunity to gain reliable information about the prey’s likely escape direction, in contrast to the unpredictable treatment where the prey’s escape angle in previous trials was not a reliable indicator of its escape direction in future encounters. If unpredictable escape behavior is adaptive, increased uncertainty about the prey’s likely escape direction in the unpredictable treatment should reduce the performance of the predator in these trials, with slower speeds of approach (i.e., before the prey respond), longer times taken to capture prey, and/or greater kinematic costs resulting from higher speeds, increased acceleration, and more turning during the pursuit.Open in a separate windowFig. 1.The robotic prey system. (A) Diagram (not to scale) showing a side view of the experimental system, with the Bluetooth-controlled robot situated on a platform underneath the experimental tank and the webcam used to monitor the predator’s movements suspended overhead. The prey’s movements are controlled by the robot via magnets, enabling the prey to escape from an attacking predator once the predator approaches within 27 cm of the prey’s starting position. See ref. 41 for a similar system designed for robotic predators attacking prey fish shoals. (B) Prey escape angles were defined relative to the predator’s approach direction. (C) In the predictable treatment, prey escaped at the same initial angle over successive trials (the escape angle varied between individual predators). In the unpredictable treatment, the prey’s initial escape angle varied randomly from trial to trial. While the experiment manipulated the prey’s initial escape angle, the prey’s subsequent escape trajectory was fixed as a straight-line path in both treatments. 相似文献
19.
目的综合应用中药石膏倒模术和红、蓝光照射治疗痤疮,观察临床疗效。方法将本院自2010~2011年两年收治的341例痤疮患者使用随机抽样分为治疗组和对照组。治疗组171例患者,每周进行1次的中药石膏倒膜治疗与红、蓝光照射治疗各一次,观察并记录患者的治疗情况;对照组170例患者,每周使用红、蓝光照射治疗各一次,观察并记录患者的治疗情况。八周为一个疗程,一个疗程后观察治疗结果 ,并对患者进行3个月的随访,观察疗效和复发情况以及并发症。结果治疗组的治疗有效率为85.38%,复发率为4.68%;对照组的治疗有效率为54.71%,复发率为30%。两组比较,差异具有统计学意义(P<0.01)。结论中药石膏倒膜治疗联合红、蓝光对治疗痤疮安全、有效,值得在临床实践推广应用。 相似文献
20.
对一株从土壤中筛选出来的产蓝色素的放线菌进行了初步鉴定, 命名为天蓝色链霉菌-100(Streptom yces coelicolor-100 ),并对蓝色素的性质进行了研究.结果表明此色素无臭无味,水溶性较强.酸性条件下,溶解度随pH 降低而减小.pH< 8 时为红色,pH≥8 时为蓝色,颜色随pH 增大而加深.于100 ℃短时间处理,比较稳定.在pH 中性的条件下对光(包括紫外光)较稳定.大多数金属离子如Ba2+ 、K+ 等对此色素无影响,Mg2+ 使色素增色.Fe2+ 在5×10-4 m ol/L时,使色素变性,但在5×10-5 m ol/L时,对色素没有多大影响.Pb2+ 可以络合色素,使之沉淀;加入0.25% 盐酸乙醇后,色素再溶解.该蓝色素可作为天然色素或天然pH 指示剂开发. 相似文献