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41.
42.
Gunkel AR Freysinger W Thumfart WF 《Archives of otolaryngology--head & neck surgery》2000,126(3):390-395
OBJECTIVE: To evaluate the benefits and difficulties encountered when using various 3-dimensional (3-D) navigation systems in head and neck procedures. DESIGN: Five different navigation systems were used for preoperative planning and intraoperative 3-D navigation in procedures at the paranasal sinuses, the frontal and lateral skull bases, and the petrous bone. INTERVENTION: Intraoperative 3-D localizing systems (position-sensitive mechanical arms, infrared cameras, etc) demand reliable patient fixation on the operating table. We achieved this by developing a noninvasive head holder. Other systems allow patient movements by using magnetic digitizing technology (ARTMA System) and sophisticated programming. RESULT: Having surpassed an initial learning curve, we now achieve an accuracy of 1 to 2 mm regularly. Especially in paranasal and frontal basal surgery, all navigation systems used provide valuable positioning information during surgery. In particular for revision or tumor surgery, decisive benefits resulted from use of these systems: shorter overall operation time; safer manipulation near delicate structures; and reliable identification of the skull base even in patients with bleeding, scarring, or missing anatomical landmarks. CONCLUSIONS: We performed approximately 250 operations with different systems and introduced navigation at the lateral skull base and the petrous bone with mechanical, optic, and magnetic digitizers. In these anatomical areas, navigation was used successfully; the technical challenge is greatest at the lateral skull base, however. 相似文献
43.
WVBS Ramalingam D Chikara G Rajagopal AVSM Prof AR Mehta S Sarkar 《Medical Journal Armed Forces India》2007
Background: Stage III and IV cancers of larynx and hypopharynx often require total laryngectomy which leaves the patient with severe communication handicap. In such laryngectomised patients tracheo-esophageal puncture is the best way for voice rehabilitation using either Blom-Singer® prosthesis or Provox® indwelling valve. 相似文献
44.
RC Johnson FRCS AR Hedges MS FRCS R Morris FFARCS JD Stamatakis MS FRCS 《International journal of clinical practice》1999,53(1):16-18
In a previous report the effectiveness of intraperitoneal bupivacaine in reducing pain following laparoscopic cholecystectomy was demonstrated. Other methods of pain relief are commonly used but none has been compared following laparoscopic cholecystectomy. In two further studies we have compared the analgesic effect of intraperitoneal bupivacaine against wound infiltration with bupivacaine, and against intraperitoneal bupivacaine with the addition of a non-steroidal anti-inflammatory drug (NSAID) in patients undergoing laparoscopic cholecystectomy. Two consecutive studies were performed. In the first, patients in group 1 were given 20 ml of 0.25% bupivacaine into the peritoneal cavity; patients in group 2 were given 20 ml of 0.25% bupivacaine injected into the trocar wounds. In the second study, patients in group 1 were given 20 ml of 0.25% bupivacaine into the peritoneal cavity; patients in group 2 were given 20 ml of 0.25% bupivacaine into the peritoneal cavity and a diclofenac suppository (100 mg) one hour before surgery. Postoperative pain was assessed with a visual analogue pain scale. There was no difference in pain scores in the two groups in either study. Intraperitoneal bupivacaine is as effective as wound infiltration. The addition of an NSAID makes no difference in the reduction of postoperative pain following laparoscopic cholecystectomy. 相似文献
45.
AR Genazzani G Sandrini F Facchinetti V Rizzo E Alfonsi G Sances M Calvani G Nappi 《Cephalalgia : an international journal of headache》1986,6(4):241-245
L-Tryptophan (L-TP) has been used in migraine and other pain conditions. The mechanism underlying the analgesic effect is still partly undefined. In this study the effects of subchronic administration of L-5-hydroxy-tryptophan (L-5HTP) (with and without carbidopa) on plasma beta-endorphin (beta-EP) levels and subjective pain threshold and tolerance were investigated in seven healthy volunteers. To measure also an objective indicator for pain, the nociceptive flexion reflex threshold was studied. L-5HTP treatment with and without carbidopa administration increased beta-EP levels significantly (p less than 0.05). L-5HTP plus carbidopa induced an increase in beta-EP significantly (p less than 0.05) higher than that after L-5HTP alone. Neither subjective pain threshold and tolerance nor RIII threshold was modified by either treatment. Our data seem to point to the existence of a complex linkage between plasma opioid levels and pain perception. 相似文献
46.
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
47.
About 126 apprentices were questioned for their knowledge and habits regarding oral health to clarify motives and hindrances, to improve the dental care programme and to attain changes of their behaviour. Good expedient and methods for improving oral health of apprentices should be--in addition to regular check up--attractive lectures and discourses, instructed training of brushing, acceptance of the individuality of the apprentices, influence of fluoride application and measures and guidelines of feeding. 相似文献
48.
The sonographic examinations of four patients with simple ectopic ureters and 11 with ectopic ureteroceles were reviewed to determine distinguishing characteristics. Ectopic ureters, in cases of extreme dilatation and tortuosity, sometimes mimic multiseptated, cystic abdominal masses. However, the proximal portions of some severely dilated ureters are surprisingly small. Ectopic ureters sometimes indent the lower vesical wall, simulating a ureterocele. Ectopic ureteroceles are dynamic structures, changing in shape and size according to intravesical pressure. The lower pole of a duplex kidney may be difficult to detect because of displacement by the dilated upper renal pelvis and ureter. The renal parenchyma associated with an ectopic ureter may be equally difficult or impossible to find because of diminutive dysplasia or, less commonly, acquired atrophy. Dysplasia is characterized sonographically by highly echogenic parenchyma, lack of corticomedullary differentiation, and occasionally massive enlargement by cysts. Ectopic ureters and ureteroceles can be identified by fetal sonography. 相似文献
49.
50.
Treatment of compulsive behaviour in eating disorders with intermittent ketamine infusions 总被引:2,自引:0,他引:2
Mills IH; Park GR; Manara AR; Merriman RJ 《QJM : monthly journal of the Association of Physicians》1998,91(7):493-503
We have previously shown that eating disorders are a compulsive behaviour
disease, characterized by frequent recall of anorexic thoughts. Evidence
suggests that memory is a neocortical neuronal network, excitation of which
involves the hippocampus, with recall occurring by re-excitement of the
same specific network. Excitement of the hippocampus by glutamate-NMDA
receptors, leading to long-term potentiation (LTP), can be blocked by
ketamine. Continuous block of LTP prevents new memory formation but does
not affect previous memories. Opioid antagonists prevent loss of
consciousness with ketamine but do not prevent the block of LTP. We used
infusions of 20 mg per hour ketamine for 10 h with 20 mg twice daily
nalmefene as opioid antagonist to treat 15 patients with a long history of
eating disorder, all of whom were chronic and resistant to several other
forms of treatment. Nine (responders) showed prolonged remission when
treated with two to nine ketamine infusions at intervals of 5 days to 3
weeks. Clinical response was associated with a significant decrease in
Compulsion score: before ketamine, mean +/- SE was 44.0 +/- 2.5; after
ketamine, 27.0 +/- 3.5 (t test, p = 0.0016). In six patients
(non-responders) the score was: before ketamine, 42.8 +/- 3.7; after
ketamine, 44.8 +/- 3.1. There was no significant response to at least five
ketamine treatments, perhaps because the compulsive drive was
re-established too soon after the infusion, or because the dose of opioid
antagonist, nalmefene, was too low.
相似文献