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991.
阿托品对兔胸主动脉平滑肌收缩和细胞增殖的影响 总被引:1,自引:0,他引:1
用兔胸主动脉条研究Atr,Ver对CaCl2,Atr对KCI量—效反应的影响。观察到Atr和Ver能抑制2种激动剂所致兔主动脉条的收缩,量一效曲线右移,最大反应降低,其pD2值分别为4.4和5.8。两药也能明显抑制NE依内Ca2+性收缩,Atr对NE依外Ca2+性收缩影响较小,说明Atr主要对细胞外Ca2+经PDC所致的收缩有抑制作用。在兔ASMC培养中,有Ca2+时,Atr抑制ASMC增殖,无Ca2+时,Atr 20.6~185.2 μmol/L表现刺激增殖,555.7~1666.7 μmol/L则抑制MSMC增殖,说明Atr对ASMC作用也与Ca(2+)有关。 相似文献
992.
Traditionally, the promotional activities of medical industries have been product specific. In recent years, however, there have been examples where companies have worked through partnerships, which have included clinicians, to expand the boundaries of treatable disorders. The main motivation appears to be to increase sales of commercial products. The term ‘disease mongering’ has been applied to these activities. Whereas some disease awareness programmes may bring benefits in the form of improved recognition and management of disorders, the presence of strong commercial interests probably distorts the traditional processes by which treatable diseases have been defined. This can result in individual patients being exposed to potential harms, with little expectation of benefit and will place an unwarranted burden on the publicly funded health‐care system. None of this can happen without the collaboration of the medical profession that needs to be aware of the risks of becoming involved in commercially supported ‘consensus’ groups that are reviewing the definition and management of diseases. 相似文献
993.
The effects on fertilization of the morphology of spermatozoa, acrosome
reaction, reactive oxygen species (ROS) production, leukocyte contamination
and the light scattering in flow cytometry of semen preparation were
investigated in 73 couples undergoing their first in- vitro fertilization
treatment. All men had normal concentrations of spermatozoa with sufficient
motility (> or = 50%) and yield (> or = 6 x 10(6)) in the semen
preparation on the day of oocyte retrieval. The light scattering properties
of all cells present in the semen preparation, as assessed with flow
cytometry, were correlated with fertilization. The proportion of metaphase
I oocytes was also correlated with the fertilization rate of all collected
oocytes and of metaphase II oocytes. ROS production, leukocyte
contamination, spontaneous or calcium ionophore-stimulated acrosome
reaction, percentage of normal morphology, and multiple anomalies index had
no independent contribution.
相似文献
994.
995.
Pelvic masses in pregnant patients: MR and US imaging 总被引:1,自引:1,他引:0
Sixteen pregnant patients with pelvic masses detected with ultrasound (US) were studied with magnetic resonance (MR) imaging at 0.35 T. Two patients were in their first trimester, eight in the second, and six in the last. On MR images, 34 masses were seen, including 19 uterine leiomyomas. With US, 20 masses were detected. All masses not seen with US were leiomyomas. Only 20 masses (in 11 patients) were removed for histologic study. In nine cases, MR imaging and US provided similar information on the origin, extent, and type of mass. In seven patients, MR imaging contributed additional information. MR imaging depicted more leiomyomas than US in three patients. In another case, MR images showed that a mass depicted with US was actually a loop of bowel. MR images allowed differentiation between a solid soft-tissue mass and a hemorrhagic fluid-containing mass, correctly depicted the presence of an abdominal pregnancy, and allowed evaluation of the parametrium for spread of cervical carcinoma. 相似文献
996.
Phase difference images, obtained by comparing data from motion-sensitized and -unsensitized spin-echo sequences, can be used to study intravoxel coherent motions. The resulting images, which have been routinely used to study fast flowing blood, may potentially yield information about perfused flows and bulk tissue motion. The likely limitations and potential of this technique applied to the central nervous system are reviewed with reference to parallel studies of intravoxel incoherent motion. 相似文献
997.
D L Morris J Jones D F Evans G Foster H Smart R Gregson S Amar J Doran J D Hardcastle 《The British journal of surgery》1985,72(12):1017-1020
Twenty-seven patients with proven longstanding gastro-oesophageal reflux underwent insertion of an Angelchik anti-reflux prosthesis. Preoperative studies included oesophageal manometry, endoscopy, acid reflux provocation test (ARPT) and 24 h oesophageal pH recording (24 h pH). Following operation mean lower oesophageal sphincter pressure was increased from 11 to 20 cmH2O. ARPT revealed significant pre-prandial reflux before operation in 16/24 compared with only 1/20 postoperatively; 24 h pH also showed an improvement in that 21/22 patients refluxed before operation compared with no significant reflux after. Dysphagia for solids of some degree was seen postoperatively in 26 patients and this was also demonstrated by delay in transit of a marsh-mallow swallow test. Severe dysphagia was seen in 4 patients and in 3 of these was related to rotation and displacement of the prosthesis necessitating removal. 相似文献
998.
Massive intracranial hemorrhage was diagnosed in utero in a 27-week-old fetus. The subsequent development of hydranencephaly was monitored by ultrasound until term. 相似文献
999.
SPRIGGS DA; FRENCH JM; MURDY JM; CURLESS RH; BATES D; JAMES OFW 《QJM : monthly journal of the Association of Physicians》1992,83(4):555-562
In a case-controlled study we recruited 400 patients admittedto hospital with stroke and 400 community controls matched forage, gender and family practitioner. Snoring history was obtainedfrom 326 patients and 345 controls. Odds ratio for admissionto hospital with stroke was 3.2 (95 per cent confidence intervals2.34.4) for regular snorers against those who did notsnore regularly. This risk was independent for age, gender andother risk factors for stroke. Snoring did not increase thechances of stroke during sleep. Level of consciousness was reducedmore frequently in snorers (p = 0.0003). As the frequency ofsnoring increased so did the mortality to 6 months (p = 0.0006).Snoring is an important risk factor for stroke and adverselyaffects the prognosis in patients admitted to hospital withstroke. 相似文献
1000.
C Rongen-Westerlaken E vd Born B Prahl-Andersen A v Teunenbroek P Manesse BJ Otten I vd Tweel AM Kuijpers-Jagtman HA Delemarre vd Waal NM Drayer JM Wit JL vd Brande 《Acta paediatrica (Oslo, Norway : 1992)》1993,82(4):364-368
A cephalometric study was performed in 19 patients with Turner's syndrome, aged 8.7–16.5 years. A lateral roentgencephalogram was taken before and after two years of treatment with biosynthetic growth hormone in a dose of 24 IU/m2 /week. During two years of growth hormone treatment, the mandibular length increased mainly due to vertical growth. The initially posteriorly rotated mandible showed an anterior rotation, although the normal position was not reached. The other linear measurements and angles did not change during treatment. No indications were found for an increase in the disproportionate growth or for excessive chin growth as a sign of acromegaly during growth hormone treatment. In conclusion, growth hormone treatment in patients with Turner's syndrome resulted in an increase in mandibular length, mainly due to vertical growth of the ramus and in the anterior rotation of the mandible. 相似文献