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61.
Journal of Clinical Immunology - Severe combined immunodeficiency is an inborn error of immunity characterized by impairments in the numbers and functions of T and B lymphocytes due to various...  相似文献   
62.
West Nile virus (WNV) is an emerging flavivirus that has caused frequent epidemics since 1996. Besides natural transmission by mosquitoes, WNV can also be transmitted through blood transfusion and organ transplantation, thus heightening the urgency of development of a specific and rapid serologic assay of WNV infection. The current immunoassays lack specificity because they are based on detection of antibodies against WNV structural proteins and immune responses to structural proteins among flaviviruses cross-react to each other. Here, we describe microsphere immunoassays that detect antibodies to nonstructural proteins 3 and 5 (NS3 and NS5). In contrast to immunoassays based on viral envelope and NS3 proteins, the NS5-based assay (i) reliably discriminates between WNV infections and dengue virus or St. Louis encephalitis virus infections, (ii) differentiates between flavivirus vaccination and natural WNV infection, and (iii) indicates recent infections. These unique features of the NS5-based immunoassay will be very useful for both clinical and veterinary diagnosis of WNV infection.  相似文献   
63.
The free radical copolymerization of 2-thienylmethyl 4-vinylbenzyl ether (TMVBE) with 2-oxo-2-(2-thienylmethoxy)ethyl-2-methylacrylate (TMOEM) has been carried out in 1,4-dioxane at 65?°C?±?1 and were analyzed by Fourier transform infrared, 1H NMR, and 13C NMR spectroscopy. 1H NMR analysis was used to determine the molar fractions of TMVBE and TMOEM in the copolymers. The monomer reactivity ratios were calculated according to the general copolymerization equation using Kelen–Tüdõs and Finemann–Ross linearization methods. The reactivity ratios indicated a tendency toward alternation copolymerization. The thermal behaviors of copolymers with various compositions were investigated by differential scanning calorimetry and thermogravimetric analysis. Also, the apparent thermal decomposition activation energies were calculated by the Ozawa and Kissinger methods with a Shimadzu TGA 60 thermogravimetric analysis thermobalance. All the products showed moderate activity against different strains of bacteria and fungi.  相似文献   
64.

Objective

Dens fractures are common cervical injuries in advanced aged patients. The presented study was undertaken to analyze the clinical results and risks of surgically treated patients with dens fractures over 70 years.

Methods

Data of 28 patients (17 female, 11 male) over 70 years treated from September 2004 to October 2009 were recorded. Clinical and radiological parameters were obtained including type of fracture, associated cervical and/or other injuries, comorbidities, symptoms, neurological condition, surgical strategy, postoperative course and complications.

Results

89% were in a good neurological condition before surgery (ASIA E or D). In most cases, surgery was performed at an early stage after trauma (21 patients within 5 days). Ventral screw fixation was the preferred surgical strategy (64%). A slight worsening of neurological functions immediately after operation was only seen in one patient. Five patients died in the early and 2 in the late postoperative course which means a treatment mortality of 25%. Among the surviving patients two had general medical complications.

Conclusion

Type II dens fractures are a common fracture of elderly patients. Our results are good concerning the neurological functions. Surgical and general medical complications were acceptable. However, the study also underlines that mortality rate is high and therefore treatment options should be well-considered in this high risk group.  相似文献   
65.
Purpose Although various non-invasive procedures have been proposed to determine the optimal level of amputation of limbs in patients who have vascular disease, currently there are no consistent criteria that can be applied before surgery. The purpose of this study was to determine whether 99mTc-sestamibi imaging can accurately predict the healing of amputation sites. Methods In a prospective study in 26 patients (21 men, 5 women; age range 23–94 years) presenting with ulcers or gangrene of the foot and hand, 99mTc-sestamibi imaging was performed preoperatively. The indications for amputation included gangrene (23 patients), electrical injury (2 patients) and trauma (1 patient) of extremities. Although the amputation levels were chosen according to clinical criteria and scintigraphic results, the final amputation level was defined by scintigraphic results. Two below-knee, one above-knee, 12 toe, 11 transmetatarsal, two phalanx, one finger and one thumb amputations and one shoulder disarticulation were performed. In four cases, the amputation defect was not suitable for coverage using a local dermal flap; rather, it was covered with free tissue transfer. Patients had clinical follow-up for 6–36 months (mean 11.69 months) to assess healing of the stump. Scan results were compared with clinical outcome to assess prediction of healing. Results There was healing in all amputations at the end of the follow-up period. When evaluated regarding preoperative 99mTc-sestamibi uptake pattern, there was no perfusion to the lesion site in 21 patients and perfusion to an area smaller than the extent of skin necrosis in four patients; thus, in these 25 patients, 99mTc-sestamibi scintigraphy suggested non-viable tissue in the extremities with clear-cut edges of perfused muscle tissue. Diffusely decreased uptake was seen below the left knee in one case. How scintigraphy changed management was analysed. The amputation levels proposed before scintigraphy were divided into two groups, “definite” (n=14) and “indefinite” (n=12), based on visual examination and Doppler findings. In nine patients in the definite group, the proposed amputation level before scintigraphy was not altered by the scintigraphic data. However, 99mTc-sestamibi scan enabled unnecessarily high amputation levels to be avoided in 12 patients in the indefinite group and in five patients in the definite group. Therefore, there was change in management of 65% of cases based on scintigraphic findings. Conclusion Since healing of the stump was seen in all cases, outcome was correctly predicted by scintigraphy. This preliminary study supports the use of 99mTc-sestamibi scan in selecting the optimal amputation level consistent with subsequent stump healing.  相似文献   
66.
The aim of this paper was to evaluate the necessity of percutaneous transhepatic catheter drainage and balloon dilation procedures performed before stent insertion. One hundred and twenty-six patients with unresectable malignant biliary obstruction underwent palliative therapy by means of percutaneous transhepatic placement of 183 metallic biliary endoprotheses. Forty-four (35%) patients underwent metallic stent insertion in a one-stage procedure and 82 (65%) had undergone percutaneous transhepatic catheter drainage before stent insertion. Balloon dilation of the stenosis before stent placement (pre-dilation) was performed in 53 (42%) of 126 patients. The rate of the 30-day mortality was 11%, with no procedure-related deaths. The total rate of early complications was 29%, and 84% of these complications were due to percutaneous transhepatic catheter drainage and pre-dilation procedures. Percutaneous transhepatic catheter drainage and pre-dilation had no clinical or statistically significant effect on the patients’ survival and stent patency rate. Percutaneous transhepatic catheter drainage and balloon dilation increased the cost of stent placement 18% and 19%, respectively. Palliation of malignant biliary obstruction with percutaneous transhepatic stent insertion should be done directly, in the simplest way, without performing percutaneous transhepatic catheter drainage and balloon dilation before stent placement. It is more useful, safe, and cost-effective.  相似文献   
67.
OBJECTIVE: Risk assessment based on plaque vulnerability would be valuable in the management of asymptomatic carotid stenosis. The purpose of this study was to compare plaque morphology in symptomatic and asymptomatic patients with significant extracranial carotid artery stenosis using MDCT angiography. MATERIALS AND METHODS: We identified 31 patients with greater than 60% carotid artery stenosis on MDCT angiography using the criteria of the North American Symptomatic Carotid Endarterectomy Trial Collaborators. We analyzed plaque density by blinded review in Hounsfield units in the atherosclerotic plaques of 15 symptomatic and 21 asymptomatic stenotic vessels for classification as soft, intermediate, or calcified. Data were analyzed using multiple logistic regression. RESULTS: Even with age, traditional cardiovascular risk factors, and treatment taken into account, we found that calcified plaques were 21 times less likely to be symptomatic than noncalcified plaques (95% confidence interval for odds ratio, 0.003, 0.749; p = 0.030). No significant predictive value was found between soft (p = 0.23) or intermediate (p = 0.18) plaque morphology for the occurrence of symptoms. CONCLUSION: MDCT angiography may help risk-stratify patients with asymptomatic carotid artery stenosis. Extracranial carotid artery calcified plaques causing stenosis are significantly less likely to be symptomatic and thus may be more stable than noncalcified plaques. This finding may have implications for the interpretation of calcification of atherosclerotic plaque in other vascular beds.  相似文献   
68.
PURPOSE: To evaluate the necessity of draining more than one hepatic duct in malignant hilar obstructions. MATERIALS AND METHODS: Two hundred seventeen self-expandable uncovered metallic stents (144 biliary Wallstents and 73 Memotherm nitinol stents) were placed percutaneously in 138 patients with unresectable malignant hilar obstructions. The patients included 76 men and 62 women, with a median age of 76 years (range, 43-82 years). Single-duct drainage was achieved in 74 patients (54%) by placing one stent (n = 59) or by placing an additional stent inserted telescopically through the first one (n = 15) to achieve an adequate stent length for long strictures (group 1). In 64 patients (46%), to maintain two-duct drainage, two stents were inserted through dual transhepatic tracts in a "Y" configuration (n = 41; group 2Y) or a single transhepatic tract in a "T" configuration (n = 23; group 2T). RESULTS: The overall technical success rate was 100%, and early clinical response was obtained in 89% of patients. The overall rate of major complications was 5.7% and did not show a statistically significant difference among groups 1, 2Y, and 2T in Bismuth type II, III, and IV obstructions. The patency rate was not statistically significant among groups 1, 2Y, and 2T in Bismuth type II and III obstructions (P >.05). However, in Bismuth type IV obstructions, the patency rate was significantly higher in group 2Y (P =.03; Kruskal-Wallis test). CONCLUSION: There is no need to place more than one stent in Bismuth type I, II, and III hilar obstructions. In Bismuth type IV obstructions, deployment of two parallel stents through dual transhepatic tracts should be performed.  相似文献   
69.
PURPOSE: To determine the effect of epidural anesthesia (EP) on oxygenation of the chronically ischemic limb in patients undergoing aorto-femoral bypass grafting and to assess whether it produces an alteration of lipid peroxidation and antioxidant status following revascularization. METHODS: In this prospective, randomized, single-blinded study 40 ASA II or III patients undergoing elective aorto-femoral bypass grafting were allocated to receive general anesthesia (group GA, n = 20), or epidural + GA (group EP, n = 20) during surgery. Femoral venous blood-gas status, activities of the protecting antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase (GSH-px), glutathione reductase (GSH-rd), glutathione (GSH) and thiobarbituric acid-reactive substances (TBARS) as a marker of lipid peroxidation were determined in blood samples taken from the femoral vein at different intervals before and after revascularization. RESULTS: Before the induction of anesthesia in group EP, femoral venous PO(2) [mean (standard deviation), 95% confidence interval] increased after achieving an adequate level of blockade by EP extending to the dermatomal level of T6-8 [29.32 (4.6), 26.34-32.30 to 36.29 (4.6), 33.37-39.22 mmHg, P < 0.05]. Femoral venous PO(2) was similar in both groups thereafter. In the GA group a significant increase in erythrocyte TBARS was observed immediately after restoration of blood flow when compared with baseline values [221.32 (102), 148.35-294-29 to 337.26 (123) 248.99-425.53 nmol*g(-1) hemoglobin, P < 0.01] but not at any other moment. In the EP group TBARS did not increase throughout the study. Within group comparisons revealed no significant differences in GSH, GSH-px, GSH-rd and SOD. CONCLUSION: In patients with atherosclerotic aorto-iliac occlusive disease EP may possibly attenuate lipid peroxidation following revascularization but has no effect on antioxidant enzyme activities.  相似文献   
70.
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