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101.
脾脏肿块的超声诊断   总被引:1,自引:0,他引:1  
目的 :探讨脾脏肿块的超声表现及鉴别要点。材料和方法 :回顾性分析 76例脾脏肿块患者的超声检查资料 ,分析脾脏肿块的大小、数目、边界、内部回声等多种超声表现。结果 :76例脾脏肿块中有 3例错构瘤 ,10例血管瘤 ,16例淋巴瘤 ,2例淋巴管瘤 ,4例血管肉瘤 ,11例脾转移瘤 ,16例脾囊肿 ,4例脾梗死 ,3例脾血肿 ,5例脾脓肿 ,2例付脾 ,其超声表现各具特征。结论 :超声检查可早期发现并区别脾脏肿块的囊、实性 ,借助彩色血流显像可进一步鉴别良、恶性病灶。  相似文献   
102.
Hepatic venous outflow tract obstruction, Budd-Chiari syndrome (BCS), leads to portal hypertension and to the development of collaterals that bypass the obstruction. Described here is a BCS patient with an unusually large transdiaphragmatic collateral between the left hepatic and left innominate veins, which decompressed the oesophageal varices. This has not been reported earlier in the literature.  相似文献   
103.
To evaluate the reliability of Doppler ultrasonography (US) in identifying children with renal artery stenosis (RAS) among those with hypertension, we compared Doppler US results in 22 hypertensive children (mean age 8.9±4.3 years), with (13 cases) and without RAS at angiography, and in 33 normotensive children (mean age 8.8±4.7 years). We observed 2 false-negatives and 2 false-positives with Doppler US. Of the 2 false-negative diagnoses, 1 had RAS on an accessory renal artery located behind a normal upper polar artery and the other was observed in a patient with bilateral multiple stenosis of the very distal segments of renal arteries. The 2 false-positive diagnoses were due to sinuous left renal artery and to technical reasons, respectively. In another patient, Doppler US showed a tight RAS, while arteriography was normal. RAS was subsequently confirmed by a second arteriography. Peak systolic velocity values of Doppler US were significantly higher in patients with proven angiographic RAS (3.44±0.66 m/s) than in hypertensive patients with normal renal arteries at angiography (0.99±0.35 m/s, P <0.0001) and normotensive healthy children (1.04±0.23 m/s, P <0.0001). With the use of multiple views, and the experience acquired with practice, false-negatives or false-positives due to the geometry of the renal artery can be avoided. Nevertheless, very distal stenosis can be missed by Doppler US. Received October 30, 1995; received in revised form April 16, 1996; accepted May 14, 1996  相似文献   
104.
Summary A duplex ultrasound system was used to examine the blood flow of the common femoral artery in ten young patients with fractures of the lower extremities. Two patients had fractures of both legs. In eight patients the blood flow in the injuried leg was comparable with that in the not injured leg. The flow alterations were measured on 3–7 different days over a period of 6–224 days after trauma. All patients showed a significant (to twice or three times that before injury) increase in blood flow in the injured leg a few days after trauma and/or operation, whereas the blood flow in the uninjured leg remained the same or even decreased a little. In the case of undisturbed fracture healing the change in blood flow disappeared within 8–12 weeks, corresponding to fracture consolidation. When fracture healing was delayed and/or further operations on the injured leg were necessary, the blood flow was increased for much longer. The hemodynamics of an injured extremity are compared with those reported elsewhere in the literature. The increased demand for oxygen or energy can explain the changes only in part. Another function of the reflective increase in blood flow could be the temperature increase in the extremity.
Doppler-sonographische durchblutungsmessungen der unteren extremität des menschenII. Hämodynamik nach trauma und operation
Zusammenfassung Mittels Doppler-sonographischer Durchblutungsmessung wurde die Hämodynamik der verletzten Extremität an 10 jungen Patienten mit Frakturen der unteren Extremität untersucht. Bei 8 Patienten konnte die Durchblutung des verletzten Beins mit der unverletzten Gegenseite verglichen werden. Die Messungen erfolgten an 3–7 verschiedenen Tagen in einem Zeitraum von 6–224 Tagen nach dem Unfall. An allen verletzten Extremitäten steigt die Durchblutung wenige Tage nach dem Unfall und/oder der Operation deutlich um das 2- bis 3fache an, während die Durchblutung des unverletzten Beins niedrig bleibt. Bei einem ungestörten klinischen Verlauf sinkt die Durchblutung in 8–12 Wochen wieder. Heilungsstörungen und weitere Operationen an dem Bein verzögern diese Normalisierung deutlich. Diese Ergebnisse werden mit anderen Untersuchungen der Literatur verglichen. Ursache und Funktion der hämodynamischen Änderungen könnte u. a. in einer reflektorischen Temperaturerhöhung zu sehen sein.
  相似文献   
105.
The relationship between internal jugular vein diameter as measured with an ultrasound imaging machine (SiteRite, Dymax) and external jugular vein diameter was studied in 50 anaesthetised patients undergoing elective cardiac surgery. There was an inverse correlation between external jugular vein diameter and internal jugular vein diameter ( r  = −0.47, p < 0.001). All patients with an external jugular vein diameter of 7 mm or greater had an internal jugular vein diameter of less than 15 mm. No patient with an external jugular vein diameter of less than 7 mm had an internal jugular vein diameter of less than 20 mm. No other patient dimension (height, weight, body mass index, neck circumference) predicted internal jugular vein size. These results suggest that a large external jugular vein (i.e. 7 mm or greater in external diameter) may be associated with a small internal jugular vein. A size 5.0-mm internal diameter tracheal tube may be used to provide a rapid assessment of external jugular vein diameter.  相似文献   
106.
Summary: We studied the effect of antiepileptic drugs (AEDs) on internal carotid artery (ICA) blood flow velocity, as an index of total cerebral blood flow (CBF). The subjects were 45 newly diagnosed children with febrile convulsion or epilepsy who were seizure-free for a period long enough not to affect the results. They had no neurologic deficit, received fixed monotherapy, and were examined by a noninvasive Doppler ultrasound method, in comparisonwith 13 age-matched normal volunteers with no AED. In 30 patients, the measurements were performed before and after AED administration [10 with phenobarbital (PB), 10 with carbamazepine (CBZ), and 10 with valproate (VPA)], and performed before and after AED discontinuation in the remaining 15 patients (all with PB). Normal volunteers underwent the two consecutive examinations with a mean interval equal to that of the entire patient group, and there was no difference in velocity values between the measurements. In patients receiving CBZ or VPA, a significant reduction was noted in blood flow velocity after drug administration. Although velocity values in the patients receiving PB did not change after drug administration, they were significantly increased after complete discontinuation. In the present study, a slight but significant reduction in CBF caused by AED administration at therapeutic doses in children was suggested.  相似文献   
107.
Laparoscopic cryosurgery for hepatic tumors   总被引:2,自引:0,他引:2  
Background: Hepatic cryosurgery has been shown to be a safe technique that may be well suited to a laparoscopic approach. Methods: The technical feasibility and safety of laparoscopic cryosurgery was explored first in a pig model. Thereafter we performed the first successful case of laparoscopic hepatic cryosurgery at our institution. Results: In the animal model, we found that it is possible to safely identify, target, and cryoablate specific lesions in the liver. Temperature in the peritoneal cavity remained above 35°C, and pathologic examination of the abdominal wall around the cryoprobe site revealed no damage. We also successfully treated a 62-year-old man with a metastatic colorectal carcinoma deep in the right lobe of the liver with laparoscopic cryosurgery using a transpleural approach. Conclusion: We conclude that laparoscopic cryosurgery is feasible for lesions anywhere in the liver. For lesions high on the dome of the liver, a transpleural approach may provide better access.  相似文献   
108.
对126列原发性肝癌与37例转移性肝癌介入治疗前均进行了B超、CT与数字减影血管造影(DSA)检查。DSA显示原发性肝癌多数血供丰富,而转移性肝癌以少血供者为主;CT显示小病灶的敏感性稍差,病灶的密度和均匀性与血供多少有一定关系,但特异性不高,而病灶的增强次应与血供关系密切,多血供者中95%有显示的增强效应,少血供者仅占4.7%;B超所示病灶的回声高低与血供亦有一定关系,但特异性稍差。结果表明,D  相似文献   
109.
经阴道超声对无症状宫外孕的诊断价值   总被引:15,自引:0,他引:15  
目的:探讨经阴道超声对无症状宫外孕的诊断价值.材料和方法:根据临床症状与体征,将24例经外科手术证实的宫外孕患者分为无症状组和有显著临床症状组,回顾性分析其声像图特征及临床资料.结果:无症状宫外孕组中,TVUS可清晰显示患者(11/13)的输卵管环征,以输卵管环征诊断宫外孕符合率为84.6%;有显著症状宫外孕组中,所有患者(11/11)未显示输卵管环征,此组宫外孕的诊断须结合临床资料.结论:TVUS对无症状宫外孕的诊断有较大的临床应用价值.  相似文献   
110.
老年退行性心脏瓣膜病与鼾症相关研究   总被引:1,自引:0,他引:1  
目的 探讨鼾症对老年退行性心脏瓣膜病 (DCVD)的影响和对心脏瓣膜结构和功能损害的特征。方法 对 4 5 2例老年鼾症患者与 4 5 2例非鼾症老人进行队列研究 ,采用彩色多普勒超声心动图检查心脏瓣膜的结构与功能。结果 老年鼾症组DCVD的发病率及严重程度与非鼾症组DCVD的发病率及严重程度相比 ,差别有非常显著性意义(P <0 0 1)。结论 鼾症可能是导致DCVD的原因之一 ,是加重心脏瓣膜结构损害与功能障碍的因素  相似文献   
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