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111.
112.
AIMS: To evaluate the role of postmastectomy radiotherapy (PMRT) in patients with pT3-T4N0M0 breast cancer. METHODS: 156 patients with T3-T4N0M0 breast cancer were retrospectively analyzed. RESULTS: Locoregional recurrences were seen in 17 of 156 patients with a median time for development of 27 months (5.7-248.7 months). Two of 9 patients who were not treated with post-operative radiation therapy had locoregional recurrence as compared with 16 of 147 patients receiving radiotherapy. In multivariate analysis, presence of locoregional recurrence was the only significant prognostic factor for overall survival (18% vs. 86%, p<0.001, RR=9.05). The patients with a median number of dissected lymph nodes >or=10 had a significantly better locoregional disease free survival rate as compared with patients with dissected lymph nodes <10 (90% vs. 78%, p=0.04). Chest wall recurrences were clearly higher in patients without chest wall RT since 5 of 49 patients without RT had recurrences in the chest wall region while only 4 of 107 who received chest wall RT had recurrence. However receiving RT to peripherical lymphatic regions had no additional effect on reducing recurrences in these regions (5% vs. 4%). CONCLUSIONS: Due to the lack of phase III randomized trials directly addressing the role of postmastectomy radiotherapy in these stages, our series suggest that postmastectomy radiotherapy to the ipsilateral chest wall is recommended for patients with PT3N0 and T4N0 breast cancer. The need for irradiating axillary or supraclavicular region shall be neglected in patients who undergo sufficient axillary sampling.  相似文献   
113.
Bagdatoglu C  Saray A  Surucu HS  Ozturk H  Tamer L 《Neurosurgery》2002,51(1):212-9; discussion 219-20
OBJECTIVE: Ischemia plays an important role in the development of pathological changes in nerve tissue, and restoration of blood flow results in injury (ischemia/reperfusion [I/R] injury) mediated by toxic oxygen free radicals. Trapidil is currently used as a coronary artery vasodilating agent and is also used for the prevention of ischemic symptoms of cerebral vasospasm. The purpose of this study was to determine the effects of trapidil on I/R injury and the ischemic tolerance of rat peripheral nerves. METHODS: Preischemia or prereperfusion administration of trapidil (8 mg/kg) was evaluated in the rat sciatic nerve I/R injury model. Nerve tissue samples from the I/R injury site were assayed for malondialdehyde (MDA), nitrites, and nitrates, as markers of I/R injury, and pathological changes were evaluated by electron microscopy. RESULTS: I/R resulted in an increase in MDA levels, which remained elevated for 2 weeks in control nerves. Rats that received trapidil before ischemia exhibited decreased MDA levels, and rats that received trapidil after the standard 3 hours of ischemia demonstrated increased tolerance to reperfusion, as reflected in significantly decreased MDA levels. Nitrite and nitrate levels in trapidil-treated rats were significantly higher than those in control animals. Histological evaluations of the sciatic nerve segments demonstrated that preischemia and postischemia trapidil treatments had a sparing effect against the myelin damage and axonal edema that are consistently noted in untreated ischemic reperfused nerves. CONCLUSION: The results confirm that pretreatment with trapidil before the ischemic insult or before reperfusion provides marked protection against I/R injury in peripheral nerves.  相似文献   
114.
Inhibition of bacterial growth by lignocaine in propofol emulsion   总被引:1,自引:0,他引:1  
Contamination of propofol, in an emulsion formulation, has been associated with infective complications. Local anaesthetics,some of which are known to have antibacterial properties, are frequently added to the solution to reduce pain on injection. We examined the growth rates of E. coli, S. aureus, S. epidermidis and P. aeruginosa in propofol with and without lignocaine 0.1%-2% after incubation for 2, 5 and 24 hours at 37 degrees C. Growth of microorganisms in each solution was compared by counting the number of colony forming units (CFU). Propofol supported the growth of all microorganisms. An increase in the number of CFUs was observed in all drug combinations 2, 5 and 24 hours after inoculation except for S. aureus (P<0.05). No difference was found in CFU numbers between 2 and 5 hours for this microorganism. With E. coli, a significant decline in colony counts was observed in mixtures of 1% and 2% lignocaine (P<0.05). With the other microorganisms only 2% lignocaine showed a significant reduction in the number of CFUs (P<0.05). We conclude that lignocaine in recommended clinical doses (0.05%-0.1%) did not exhibit adequate antibacterial activity to prevent infective complications.  相似文献   
115.
PURPOSE: To investigate the penetration of cefepime (a fourth-generation cephalosporin) into the vitreous after single-dose intravenous administration to human subjects. METHODS: Thirty phakic patients about to undergo vitreous surgery received 1 g (group 1, 15 patients) or 2 g cefepime (group 2, 15 patients) in a single intravenous injection before surgery. The indications for vitreous surgery were retinal detachment with proliferative vitreoretinopathy (24 patients), retinal detachment associated with giant retinal tear (4 patients), macular hole (1 patient) and intraocular foreign body (1 patient). Samples of vitreous and serum were obtained at 0.5, 1, 2, 4 and 12 h after injection. Three patients were used for each sampling time and for 1 g and 2 g of cefepime. Samples were assayed for cefepime concentrations with high-performance liquid chromatography (HPLC). RESULTS: All the patients had detectable cefepime in their vitreous and serum measurable by HPLC. The level of cefepime in the vitreous peaked at 2 h and reached a minimum at 12 h after intravenous injection in both groups. A mean peak vitreous level of cefepime was 1.91 +/- 0.13 microg/ml in group 1 and 2.86 +/- 0.37 microg/ml in group 2. The level of cefepime in the vitreous at 12 h after injection was 0.89 +/- 0.14 microg/ml in group 1 and 0.97 +/- 0.30 microg/ml in group 2. CONCLUSION: The vitreous level of cefepime after intravenous injection was below the minimum inhibitory concentration (MIC(90)) against Staphylococcus aureus, Staphylococcus epidermidis and Pseudomonas aeruginosa, but was over the MIC(90) against Proteus mirabilis, Klebsiella spp., Haemophilus influenzae, Streptococcus pneumoniae, Streptococcus pyogenes and Enterobacter spp.  相似文献   
116.
Incidence of cochlear involvement in hyperbilirubinemic deafness   总被引:6,自引:0,他引:6  
Neonatal hyperbilirubinemia remains an important cause of childhood deafness, especially in developing countries. After neonatal hyperbilirubinemia, the auditory neural pathways, cochlea, or both may be affected. In this study, we aimed to determine the incidence of cochlear impairment and the appropriate means of hearing screening in hyperbilirubinemic neonates. A retrospective review of 1,032 pediatric patients with hearing loss revealed 67 cases (6.5%) of severe hyperbilirubinemia in the neonatal period. Thirty of these patients had neonatal hyperbilirubinemia as the single identifiable risk factor for hearing loss. In 26 of 30 cases (87%), otoacoustic emissions (OAEs) were absent, whereas in the remaining 4 cases (13%), robust emissions were detected despite an absent auditory brain stem response (ABR). Auditory screening of newborns with jaundice by OAEs possesses a significant risk of undiagnosed deafness. On the other hand, if the ABR is used as the single means of screening, auditory neuropathic conditions will probably be underlooked. Therefore, we recommend dual screening of hearing by ABR and OAEs in hyperbilirubinemic newborns.  相似文献   
117.
The purpose of this study was to examine the effect of glass fibre reinforcement on the dimensional changes and water sorption of a heat-polymerising denture acrylic polymer and a microwave-polymerising denture acrylic polymer. Fifteen specimens from each group were prepared with 2% by weight (18 mg) E-glass fibre and 15 without glass fibre. The dimensional change measurements were made at three different stages on the 60 specimens. The water sorption calculations were made on specimens immersed in distilled water at 37 degrees C +/- 1 degree C for 0, 1 and 7 days. Glass fibre reinforcement and processing method do not affect the dimensional change of test specimens, but as the time increased the dimensional change decreased. The glass fibre reinforcement decreased water sorption, but the two processing methods failed to show a significant difference.  相似文献   
118.
Losartan, an angiotensin II receptor antagonist, is widely used for the treatment of hypertension. Clinical experience with this drug has demonstrated that it is safe. Losartan-induced hepatic toxicity is extremely rare. We report a case of severe hepatic toxicity and fibrosis caused by losartan use, and we review four previously reported cases. Drug-induced hepatic injury may be seen during the treatment of hypertension by losartan and the clinician should be aware of this toxicity, especially during the initial phase of treatment.  相似文献   
119.
Evaluation of anticoagulant system in Turkish children with Perthes disease   总被引:1,自引:0,他引:1  
BACKGROUND: Perthes Disease (PD) is generally a self-limiting disease of childhood but it causes severe pain and may lead to deformity of the femoral head. Intravascular thrombosis seems to form the main mechanism in the pathogenesis of the disease. The aim of this study was to determine hereditary thrombotic risk factors in Turkish children with PD. METHODS: In 46 Perthes patients (35 male, 11 female), family history of thrombotic events was investigated, Protein C (PC), free-Protein S (f-PS), antithrombin (AT) activities, fibrinogen level, and resistance to activated Protein C (APC) were measured. The results were compared with a healthy control group of 79 children matched by age and sex. The relationship between the severity of disease and coagulation system abnormalities was evaluated. RESULTS: While the mean PC and AT activities were significantly lower in the patients than those of the controls, the proportions of patients with low AT activity, resistance to APC, and a history of hereditary thrombophilia were significantly higher than those of the controls. No difference was observed in coagulation system disorders relative to severity of the disease and bilateral or unilateral disease involvement. CONCLUSIONS: This study shows that a possible association between PD and inherited hypercoagulability. Determination of thrombotic risk factors in these patients may bring a new approach to the treatment. Most importantly, this may be a stimulant to take precautions for other thrombotic events, which patients may face later in life.  相似文献   
120.
The aim of this study was to determine the incidence of laryngeal tuberculosis (LT) among patients with active pulmonary tuberculosis. A total of 319 patients under treatment for pulmonary tuberculosis were subjected to laryngoscopy. Five patients (1.5%) with LT were identified. Odynophagia was the most common complaint, followed by alteration in voice. The larynx returned to its normal appearance in 3–8 months (average 18 weeks) by antituberculous medication. Physicians dealing with pulmonary tuberculosis should keep in mind that symptoms of laryngeal involvement may be minor, and laryngoscopy should always be performed when laryngeal involvement is suspected in order to isolate highly infectious patients. Response to antituberculous medication is usually late in LT and diagnosis by “wait and watch” policy will cause a significant delay in the diagnosis of a possible larynx carcinoma.  相似文献   
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