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Forty patients who were managed conservatively after haemorrhage from an endoscopically verified duodenal ulcer were randomised at discharge from hospital to enter a blind study of ranitidine therapy (150 mg bd) versus a placebo tablet. The patients were re-endoscoped after four weeks, ulcer status defined and the trial code broken revealing that five of 20 placebo patients had healed their duodenal ulcer compared with 16 of 20 ranitidine patients (p = 0.001). Lifestyle parameters of both groups improved during the study period but no directly related benefit in duodenal ulcer healing could be shown. We conclude that effective anti-ulcer therapy, such as ranitidine, is required to heal a duodenal ulcer which presents with haemorrhage. 相似文献
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Eyleen LK Goh Ju Kim Young Kenichiro Kuwako Marc Tessier-Lavigne Zhigang He John W Griffin Guo-li Ming 《Molecular brain》2008,1(1):1-14
Several myelin-associated factors that inhibit axon growth of mature neurons, including Nogo66, myelin-associated glycoprotein (MAG) and oligodendrocyte myelin glycoprotein (OMgp), can associate with a common GPI-linked protein Nogo-66 receptor (NgR). Accumulating evidence suggests that myelin inhibitors also signal through unknown NgR-independent mechanisms. Here we show that MAG, a RGD tri-peptide containing protein, forms a complex with β1-integrin to mediate axonal growth cone turning responses of several neuronal types. Mutations that alter the RGD motif in MAG or inhibition of β1-integrin function, but not removal of NgRs, abolish these MAG-dependent events. In contrast, OMgp-induced repulsion is not affected by inhibition of b1-integrin function. We further show that MAG stimulates tyrosine phosphorylation of focal adhesion kinase (FAK), which in turn is required for MAG-induced growth cone turning. These studies identify β1-integrin as a specific mediator for MAG in growth cone turning responses, acting through FAK activation. 相似文献
56.
Peptic ulcer and gastric carcinoma: diagnosis with biphasic radiography compared with fiberoptic endoscopy 总被引:1,自引:0,他引:1
Shaw PC; van Romunde LK; Griffioen G; Janssens AR; Kreuning J; Eilers GA 《Radiology》1987,163(1):39-42
The diagnostic value of biphasic radiographic examination of the stomach and duodenum was compared with that of fiberoptic endoscopy in a prospective, blinded study of 385 patients with dyspepsia. This investigation was directed at gastric malignancies and peptic ulcers. Methodologically there is no absolute standard for a study of this kind because histologic examination is useful for detection of cancer but inadequate for ulcers. As an alternative, kappa indexes and the sensitivity and specificity, as derived by Hui and Walter, were calculated and compared. For the detection of gastric carcinoma, radiographic and endoscopic findings had almost perfect agreement beyond chance. For gastric ulcers, radiography and endoscopy had substantial agreement, which became perfect if small ulcers (less than 5 mm) were excluded. For duodenal ulcers, radiography had a lower sensitivity than endoscopy; this disagreement disappeared if small ulcers were excluded. Both methods have equal merit; choice of the initial diagnostic procedure will therefore depend on cost, discomfort to the patient, and risk of complications. 相似文献
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Sternocleidomastoid flap following parotidectomy 总被引:2,自引:0,他引:2
The sternocleidomastoid (SCM) muscle has been used in various ways for reconstruction following cancer resections in the head and neck. Its use has been restricted because of the presumed precarious nature of its blood supply and its proximity to disease. Patients with large or recurrent benign parotid tumors were the first in our series to have a SCM muscle flap (either superiorly or inferiorly based) used to improve cosmesis. After demonstrating the utility of these flaps, we extended the indications for their use to include patients with primary or recurrent malignant disease. The flaps provide soft tissue contour, coverage of facial nerves and nerve grafts, act as a healthy bed for skin grafts, and help close salivary fistulas. There were no complications attributed to the flaps. This paper discusses 31 patients with benign and malignant parotid disease in whom the SCM flap was used. 相似文献
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S A Amiel H R Archibald G Chusney A J Williams E A Gale 《Clinical science (London, England : 1979)》1991,81(2):189-194
1. The effect of hyperketonaemia on counter-regulatory hormone responses to hypoglycaemia has been examined in six healthy subjects. 2. A controlled, step-wise reduction in blood glucose concentration was achieved by adjusting the rate of glucose infusion during a primed-continuous infusion of soluble insulin (1.5 m-units min-1 kg-1 body weight, plasma insulin concentration approximately 90 m-units/l). Simultaneous infusion of either saline or beta-hydroxybutyrate (3 mg min-1 kg-1 body weight) was administered in a single-blind fashion, in random order. Despite a need for 40% more glucose during the ketone infusion, an identical fall in blood glucose concentration was achieved in each study. 3. The glycaemic threshold for stimulating an adrenaline response of 0.41 nmol/l was reduced from 3.1 to 2.8 mmol/l (P less than 0.05) during ketone infusion, and that for stimulating a response of more than 50% of basal from 3.6 to 3.1 mmol/l (P less than 0.001). The peak adrenaline response fell from 7.97 to 2.6 nmol/l (P less than 0.04). Peak noradrenaline, cortisol and growth hormone responses were also significantly lower during ketone infusion (P = 0.04, 0.001 and 0.006, respectively). Glucagon responses alone were unaffected by hyperketonaemia. 4. The provision of an alternate metabolic fuel thus produced immediate changes in the neurohumoral responses to hypoglycaemia. This is consistent with the hypothesis that human nervous tissue can metabolize ketones acutely. 相似文献
60.
Fine-needle aspiration biopsy is a relatively simple procedure that is becoming increasingly popular among physicians in the United States. It has provided significant advancement in the diagnosis of a number of pathologic conditions of the head and neck as well as other areas, especially those presenting as palpable masses or nodes. At present, many situations that previously would have required open biopsy or surgical removal of a mass lesion for diagnosis can now be diagnosed safely and accurately with fine-needle aspiration biopsy. The speed, safety, patient acceptability, low cost, and accuracy of fine-needle aspiration biopsy make it a valuable addition to any diagnostic armamentarium. 相似文献