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41.
Numerous studies have replicated the finding that schizophrenia patients make an increased number of errors on an antisaccade task. Some studies have reported that relatives of schizophrenia patients also make an increased number of antisaccade errors, a finding that has been interpreted to support the usefulness of compromised antisaccade performance as an index of genetic liability for schizophrenia. We examined performance on an antisaccade task in schizophrenia patients, nonpsychiatric controls, first-degree relatives of schizophrenia patients and first-degree relatives of nonpsychiatric controls. Schizophrenia patients made significantly more errors than did nonpsychiatric controls, but relatives of schizophrenia patients did not differ from relatives of controls or from all controls. Increased antisaccade errors on the standard version of the antisaccade task are associated with schizophrenia, but do not seem to be a co-familial trait for schizophrenia.  相似文献   
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BACKGROUND: Ophthalmologists and ocular pathologists are called on to help identify children who have undergone violent shaking. The objective of this study was to describe the spectrum of postmortem ocular findings in victims of shaken baby syndrome and to correlate the ocular findings with the nonocular features found at autopsy. METHODS: The ocular pathology registry at the University of Ottawa Eye Institute was reviewed to identify all victims of fatal shaken baby syndrome whose eyes had been submitted for examination between Apr. 1, 1971, and Dec. 31, 1995. Autopsy reports were accessed from the hospital charts of the identified patients. RESULTS: Six patients, aged 1 to 34 months, were identified. Intraocular findings ranged from a focal globular hemorrhage at the posterior pole to extensive intraocular hemorrhage involving the entire retina with perimacular folds. All the children had evidence of optic nerve sheath hemorrhage. Nonocular findings included intracranial hemorrhage (in all cases), skull fracture (in two), rib fractures (in three) and high spinal cord hemorrhage (in four). The extent of the intraocular hemorrhage was not consistent with the nonocular findings. INTERPRETATION: Abused children may display a range of postmortem ocular findings, with intraocular hemorrhage varying from minimal to severe. These findings may not correlate with the severity of the child's other injuries. The presence of any retinal or optic nerve sheath hemorrhage in an infant, in the absence of an appropriate explanation for these findings, should raise suspicion of child abuse.  相似文献   
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This article addresses electrophysiologic evaluation of the distal AV conduction system in patients with chronic bifascicular block. It was formerly thought that progression to complete AV block was a common cause of morbidity and even sudden death in this condition, and it was hoped that electrophysiologic evaluation, including measurement of the H-V interval, would facilitate prospective identification and prophylactic treatment of patients prone to these complications. However, a decade of clinical investigation has revealed that progression to complete AV block is rare and that although cardiovascular mortality, including sudden death, is substantial, this mortality usually relates to underlying organic heart disease. The current role for electrophysiologic studies in chronic bifascicular block is limited to delineation of the site of electrocardiographically documented second- or third-degree AV block and to the evaluation of unexplained syncope.  相似文献   
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This study compared oral irrigation and rinsing with chlorhexidine (CHX) and placebo in the treatment of naturally occurring chronic gingivitis. 44 subjects with at least 6 interproximal sites which bled on probing were randomly distributed on a double-blind basis into 4 treatment groups, placebo-rinse, CHX-rinse (0.12%), placebo-irrigation and CHX-irrigation (0.06%). A half-mouth was scaled 2 weeks prior to therapy in all groups. Rinses were performed 2 times daily and irrigation was performed once a day by means of an oral irrigator with the tip directed at a right angle to the tooth. Subjects continued with routine oral hygiene without instruction. The active treatment period was 2 months. Parameters were recorded at baseline and at 60 days. At the conclusion, marginal plaque was cultured for predominant microbial types. CHX-rinse (0.12%) and CHX-irrigation (0.06%) significantly reduced (p less than 0.05) plaque. Gingival bleeding decreased by 26% in both scaled and unscaled sites following CHX (0.12%) rinses and by 40% at both types of sites following CHX (0.06%) irrigation. Bleeding was reduced with CHX-irrigation greater (p less than 0.05) than with the placebo-irrigation. The mean log of colony-forming units of Actinomyces species was significantly lower (p less than 0.05) in the CHX (0.12%) rinse and CHX (0.06%) irrigator groups than in the placebo groups. These data therefore indicate that delivery of CHX (0.06%) by an oral irrigator is an effective means of treating naturally occurring gingivitis.  相似文献   
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Functional changes in Kupffer cells occur after profound hemorrhagic shock. This study was performed to demonstrate if Kupffer cell changes also occur after mild hemorrhagic shock. Sprague-Dawley rats were bled to a systolic blood pressure of 60 to 70 mmHg and resuscitated with Lactated Ringers solution (twice the shed blood volume) after 30 min. Resuscitation produced immediate recovery of blood pressure and allowed long-term recovery of the animals. Sham animals received anesthesia and monitoring only. Thirty minutes after resuscitation, Kupffer cells were isolated by centrifugal elutriation and cultured for 48 h. In Kupffer cells isolated from shocked animals, phorbol ester-stimulated superoxide production increased 7-fold and lipopolysaccharide- (LPS) stimulated prostaglandin E2 (PGE2) production increased 4-fold. Tumor necrosis factor-alpha (TNFalpha) production, on the other hand, was decreased by 50%. A non-significant trend toward increased phagocytosis was also observed, whereas LPS-stimulated nitric oxide production was unchanged. In conclusion, mild hemorrhagic shock produced increases in superoxide and PGE2 production, and decreases in TNFalpha production by Kupffer cells, changes that may be appropriate to defend against the infectious challenges that often follows trauma and hemorrhage.  相似文献   
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A number of factors have been proposed as potential mediators of the syndrome of humoral hypercalcemia of malignancy (HHM), but to date no firm cause-and-effect relationship has been established. We attempted to establish such a relationship by determining whether the presence or absence of adenylate cyclase-stimulating activity (ACSA) in the media of cultured tumor cells predicted the occurrence of the syndrome of HHM when these cell lines were grown in nude mice in vivo. Conditioned media from 35 human renal carcinoma cell lines were surveyed for ACSA in the PTH-sensitive rat osteosarcoma 17/2.8 cell assay. 12 lines were positive (mean, 13.7-fold stimulation, range, 3.0 to 44.0), and 23 lines were negative (mean, 1.2-fold stimulation, range, 0.9 to 1.5). We were successful in establishing five of the positive and six of the negative lines in three to five nude mice per line. Mice implanted with the positive lines uniformly became hypercalcemic (mean serum calcium, 15.8 mg/dl), whereas mice implanted with the negative lines uniformly remained normocalcemic (mean serum calcium, 9.5 mg/dl), in spite of comparable mean tumor size. Acid-urea tumor extracts from each of four hypercalcemic animals contained potent in vitro ACSA (mean, 15.9-fold stimulation), while 5/5 extracts from normocalcemic animals did not (mean, 1.4-fold stimulation). Our study demonstrates that in this model system in vitro ACSA is a reliable predictive marker for HHM in vivo. Whether the protein responsible for this activity is also the mediator of the bone resorption seen in HHM remains to be demonstrated.  相似文献   
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