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101.
Induction of neurite outgrowth from superior cervical ganglia (SCG) by rat lymphoid tissues was studied using a tissue culture model. Neonatal rat SCG were cultured with 6–12-week-old rat thymus, spleen, or mesenteric lymph node (MLN) explants in a Martrigel layer, in defined culture medium without exogenous nerve growth factor (NGF). SCG were also co-cultured with neonatal rat heart (as positive control) or spinal cord (SC; as negative control). To determine whether inflammation affects the ability of lymphoid tissues to induce neurite outgrowth, we also examined MLN at various times after infecting rats with Nippostrongylus brasiliensis (Nb-MLN). In one series of experiments, a single lymphoid tissue explant was surrounded by four SCG at a distance of 1 mm. The extent of neurite outgrowth was determinded by counting the number of neurites 0.5 mm away from each ganglion at several time points. Adult thymus and, to a lesser extent, spleen had strong stimulatory effects on neurite outgrowth from SCG after 12 hr or more in culture. For thymus tissue, this was similar to the positive control heart explants. MLN from normal rats had minimal effect on neurite outgrowth; however, Nb-MLN showed a time-dependent enhancement of the neurite outgrowth, maximal at 3 weeks after infection. The relative efficacy of neurite outgrowth induction (heart ≥ thymus ≥ Nb-MLN ≥ spleen ≥ MLN ≥ SC) was confirmed in a second series of experiments where one SCG was surrounded by three different tissue explants. We then examined the role of 2.5S NGF, a well-known trophic factor for sympathetic nerves, in the lymphoid tissue-induced neurite outgrowth. Anti-NGF treatment of co-cultures of SCG and heart almost completely blocked the neurite outgrowth. Anti-NGF also significantly inhibited thymus- and spleen-induced neurite outgrowth, but not as effectively as heart-induced neuritogenesis (93,80, and 77% inhibition at 24 hr; 86,70, and 68% inhibition at 48 hr for heart, thymus, and spleen, respectively). On the other hand, anti-NGF inhibited only 8% of neurite outgrowth induced by 3-week post-infection Nb-MLN at 24 hr, and 41% at 48 hr. These data show that several adult rat lymphoid tissues exert neurotrophic/tropic effects. The predominant growth factor in thymus and spleen is NGF, while Nb-MLN produces factor(s) which is (are) immunologically distinguishable from NGF. These neurotrophic/tropic factors are produced during the reactive lymphoid hyperplasia that forms part of the inflammatory response against the nematode, N. brasiliensis. This suggests the possibility that cytokines produced by lymphocytes or other inflammatory cells may stimulate sympathetic neurite outgrowth in vivo. © 1994 Wiley-Liss, Inc.  相似文献   
102.
In humans, cardiovascular adjustment to simulated diving causes a marked increase in sympathetic outflow to intramuscular vessels and muscle vasoconstriction. Skin vasoconstriction in the hand also occurs during diving in humans. Skin nerve sympathetic activity (SSA), containing vasoconstrictor signals to glabrous skin, unexpectedly was reduced during diving in a previous study of SSA recorded in the peroneal nerve. SSA was recorded by microneurography in the median nerve in 13 healthy volunteers during simulated diving. Skin blood flow in the hand and one finger was monitored. The typical SSA response, irrespective of duration of diving and water temperature, was an increase during the control period immediately prior to immersion of the face and a sudden reduction of SSA when the face was immersed. The increase in SSA preceding the dive was accompanied by vasoconstriction, which continued during the dive, but re-dilation regularly occurred before the end of the dive. Inhibition of SSA was not total. Mental arithmetic during diving evoked strong bursts of SSA, similar to those seen normally during mental stress. It is concluded that the true response of SSA to simulated diving is an inhibition of the immediately preceding outflow, in agreement with observations of cutaneous blood flow in animals. The skin vasoconstriction recorded during simulated diving is a consequence of an SSA increase before the procedure, suggested to be a stress response before the forthcoming manoeuvre. The SSA response during simulated diving is the opposite to that of sympathetic outflow to muscle, which emphasizes the diversity of sympathetic regulation of different organ systems.  相似文献   
103.
颈椎侧块钢板在脊髓型颈椎病治疗中应用   总被引:2,自引:1,他引:1  
目的 对15例脊髓型颈椎病患者行后入路椎管减压、椎板成型术的同时使用颈椎侧块钢板固定,探讨和分析该手术方法的优点和手术治疗效果。方法 从自2000年3月—2002年12月,对15例脊髓型颈椎病患者(术前颈椎MR显示有三个节段颈椎椎间盘水平病变并有黄韧带增厚突入椎管),行颈椎后入路双开门椎板成型术加双侧颈椎侧块钢板固定。按JOA评分法评定患者手术前后恢复情况。结果 本组患者男10例,女5例,随访5个月—1年2个月,平均9个月,术后2—7天(平均3.5天)可戴颈围坐起,颈围外固定时间12周,融合时间3—5个月,(平均为3.5个月),术后JOA评分明显提高,所有病人无术中血管、神经根损伤,无植骨不愈合,无内固定断裂。结论 行颈椎后入路双开门椎板成型术联合应用颈椎侧块钢板固定,从后方扩大椎管容积,对脊髓进行减压,辅助以侧块钢板对减压后的颈椎行即时的稳定的固定,增加后方所植髂骨的融合成功率,大大地减少颈椎术后后突畸形发生和术后卧床并发症的发生率。  相似文献   
104.
颈椎前路钢板在脊髓型颈椎病前路手术中的作用   总被引:10,自引:2,他引:8  
目的 评价内固定在脊髓型颈椎病前路减压中的作用。方法 143例脊髓型颈椎病患者经前路减压后自体髂骨植骨,带锁钢板内固定。获得随访病例132例,随访时间平均20个月,观察术后神经功能恢复情况,植骨融合率,椎间高度及颈椎生理曲度恢复情况。结果 单节段与两节段病变者术后3月均获得骨性愈合,融合率为100%,16例3节段病变者融合体为81.3%,内固定并发症为5/132(3.8%)。术后椎间高度与生理曲度均获得满意重建。JOA记分平均改善率65.8%。结论 在脊髓型颈椎病前路减压手术中应用带锁钢板内固定可有效维持椎间高度和生理曲度,并有助于后路间接减压。  相似文献   
105.
[目的]探讨伴有上肢局部水肿的颈椎病患者的发病机理和与手术颈椎减压的关系。[方法]总结分析4a来收治的10例伴有上肢局部水肿的颈椎病人,其中脊髓型颈椎病7例,神经根型颈椎病2例,后纵韧带骨化型1例,7例行前路椎体次全切减压植骨内固定,1例行前路椎体次全切+单间隙间盘摘除植骨内固定,2例行后路减压植骨内固定,术后观察患者水肿消退情况。[结果]10例病人上肢局部水肿不同程度消退,前路手术者较后路手术者消退快。[结论]颈椎病患者上肢水肿的发生与颈交感神经受激惹有关,通过前路或后路颈椎管减压,去除颈椎不稳、椎间盘突出、骨赘等交感神经受激惹因素,水肿可逐步消退。  相似文献   
106.
目的:评价Cervifix固定垂直水平悬吊改良单开门椎管成形术的疗效。方法:35例颈椎病患者,男23例,女12例;年龄47~68岁,平均56·4岁;34例为脊髓型颈椎病,1例为颈椎术后翻修;椎管矢状径4·6~9·3mm;椎管矢状面狭窄率达39%~84%,平均49·3%;减压节段C3-C59例,C3-C620例,C4-C76例。常规行后正中入路单开门椎管成形术,在所减压的节段侧块上Cervifix固定,采用Roy-Camille置入侧块螺钉。先用磨钻在所减压节段的棘突根部开预穿孔,开门后穿粗丝线于Cervifix的纵连杆拉紧并打结,行水平方向固定。垂直方向在开门侧的椎板上打预穿孔,用“斜拉桥”原理悬吊于临近未减压的棘突上加固。使椎板保持在开门状态。术后颈围领保护3个月。结果:35例平均随访15个月(7~18个月)。术前JOA评分平均8·0分,术后平均15·7分。术后3个月复查CT及X线片未见螺钉松动和再关门现象。仅有3例诉颈部有僵硬感,局部无疼痛。肌电图及体感诱发电位、感觉运动传导速度基本接近正常。6个月后僵硬感基本消失。结论:Cervifix固定垂直水平悬吊改良单开门椎管成形术操作简单、安全,维持开门效果好。术后患者颈部症状恢复快、效果满意,是治疗多节段颈椎病及颈椎管狭窄症的一种有效可行的方法。  相似文献   
107.
The presence of hypoxic cells is one of the major factors affecting resistance against radiation therapy. In the clinical setting, little information exists as to the relationship between intratumoral oxygen partial pressure (pO(2)) and outcome. This study involved 30 consecutive patients with cervical cancer, who were treated with a combination of external and high-dose rate intracavitary irradiation. The pO(2) was measured before radiation therapy and at 9 Gy, using a needle-type polarographic oxygen electrode. The mean intratumoral pO(2) before radiation therapy was 17.3 +/- 10.8 mm Hg. The 3-year local control rates of patients with pO(2)< or = 20 mm Hg and pO(2) > 20 mm Hg before radiation therapy were 52% and 100%, respectively, representing a significant difference (P= 0.035). At 9 Gy, mean intratumoral pO(2) was 23.6 +/- 9.1 mm Hg, a significant increase compared to the value before radiation therapy (P= 0.006). The 3-year local control rates of tumors with pO(2)< or = 20 mm Hg and pO(2) > 20 mm Hg at 9 Gy were 35% and 93%, respectively, representing a significant difference (P= 0.001). The significantly better local control for oxygenated tumors at 9 Gy as well as before radiation therapy indicated that the oxygen effect and reoxygenation by radiation played an important role in local control in radiation therapy for cervical cancer.  相似文献   
108.
The reliability and applicability of colposcopically directed cervical punch biopsy was assessed in a sample of 170 paired punch and large loop excision of cervical transformation zone (LLETZ) specimens obtained from previously untreated women who had been selected for treatment on the basis of cytology and/or colposcopic findings and in whom the entire cervical transformation zone was visible. A single punch biopsy was taken immediately before the LLETZ, and all the specimens were reviewed by a single pathologist. Nine (5.3%) punch biopsies were inadequate. In terms of whether or not there was cervical intraepithelial neoplasia (CIN), the chance-corrected kappa analysis rated overall agreement as poor (kappa = 0.21, 95% confidence limits 0.02-0.39), whereas in terms of histologic grade, it was fair to moderate (kappa = 0.32, 95% confidence limits 0.23-0.42). Punch biopsy tended to underestimate the disease. The sensitivity and specificity of colposcopically directed punch biopsy for the detection of high-grade CIN was 74% and 91%, respectively, with positive- and negative predictive values of 97% and 48%, respectively. Two microinvasive and two intraepithelial glandular lesions were missed on punch biopsy. Punch biopsy should be avoided when high-grade disease is suspected.  相似文献   
109.
In this study, we evaluated the presence of human papillomavirus (HPV) DNA in organs of the female upper genital tract, using nine hysterectomy and salpingo-oophorectomy specimens affected by HPV-positive invasive cervical carcinomas, to establish if cervical HPV infection can spread to upper tracts of the female genital system. HPV DNA was evaluated by polymerase chain reaction (PCR) in all cervical carcinomas as well as in all tracts of the genital system. Then, these data were compared with the results obtained from PCR study of five other hysterectomy and salpingo-oophorectomy specimens (control cases). The criteria used for selection of the control cases were informed consent of the patients for research at the time of surgery, absence of neoplasms, absence of any anatomic lesion caused by HPV in cervix, and external genitalia. All selected cases were squamous cervical carcinomas. PCR analysis revealed HPV DNA in all cases of cervical carcinoma. The HPV DNA was detected as weak positivity on PCR analysis in other organs of the genital system. However, the distribution of HPV DNA varied in the various cases and in the different tracts of the same hysterectomy and salpingo-oophorectomy specimen. We believe that the HPV DNA, detected as a weakly positive signal, in the upper genital tract of patients who have a cervical squamous carcinoma could be a reflection of a latent HPV infection, as well as a sign of the existence of micrometastases containing HPV DNA, which cannot be detected by conventional histologic techniques.  相似文献   
110.
目的观察颈丛阻滞下行颈动脉内膜剥脱术的效果.方法 28名ASAⅡ~Ⅲ级患者行32例颈动脉内膜剥脱术,采用深浅丛联合阻滞,观察围术期血液动力学指标变化,分流管放置率和并发症情况.结果 麻醉后血压和心率与麻醉前相比差异有显著性(P<0.05),其它时点与麻醉前相比差异无显著性(P>0.05).颈动脉夹闭前后收缩压和心率的波动性的差异无显著性(P>0.05).围术期高血压的发生率为50.0%,低血压6.25%,心动过速28.1%,心动过缓6.25%,分流管放置率6.25%.患者满意率84.4%.无1例改用全麻,无严重围术期并发症.结论颈丛阻滞是颈动脉内膜剥脱术安全、有效的麻醉方法.  相似文献   
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