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51.
A 39-year-old woman was hospitalized for nephrotic syndrome. Laboratory test results showed increased serum creatinine levels and urinary excretions of beta-2-microglobulin, and N-acetyl-beta-D-glucosaminidase. A renal biopsy revealed collapsing focal segmental glomerulosclerosis (FSGS) and acute interstitial nephritis. Despite treatment with pulse steroid followed by oral high-dose glucocorticoids and cyclosporines, heavy proteinuria persisted. After low-density lipoprotein apheresis (LDL-A) therapy was initiated, her proteinuria gradually decreased, leading to complete remission. A repeat renal biopsy after treatment revealed no collapsing glomeruli. Immediate LDL-A should be performed to treat cases of collapsing FSGS poorly responding to other treatments.  相似文献   
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53.
Summary We have recently shown that the mechanical efficiency of the contractile machinery of the canine left ventricle is constant at 30%–50%, independent of its loading, heart rate, and inotropic conditions. In contrast, the conventional mechanical efficiency of the ventricle is known to vary between 0 and 30%, depending on these conditions. In this study, we derived an equation for the conventional mechanical efficiency as a function of ventricular preload, afterload, and contractility, based on the constant mechanical efficiency of the contractile machinery. In deriving this equation, we fully utilized our new concept of the total mechanical energy of the left ventricle, i.e., systolic pressure-volume area, and our recent findings of the linear relationship between left ventricular oxygen consumption and the systolic pressure-volume area as well as the dependence of this relation on the ventricular inotropic state. As a result, the conventional mechanical efficiency of the left ventricle was found to change between 0 and 25% as an explicit function of these cardiodynamic and inotropic conditions. Using this function, we obtained combinations of loading and inotropic conditions to maximize the conventional mechanical efficiency of the left ventricle.  相似文献   
54.
Purpose. Ketamine is known to interact with opioid receptors. However, because this agent does not produce opioid-like respiratory depression, it might not interact with μ2 opioid receptors. Therefore, we have studied the interaction of ketamine with μ2 opioid receptors expressed in SH-SY5Y cells. Methods. SH-SY5Y cells (passage 70–80) were used to obtain ketamine dose-response curves for inhibition of 0.4 nM [3H][d-Ala2,MePhe4,Gly(ol)5] enkephalin (DAMGO) binding to μ2 opioid receptors and of forskolin (1 μM)-stimulated cyclic AMP (cAMP) formation. Results. Ketamine displaced [3H]DAMGO binding in SH-SY5Y cells with a K i of 12.1 μM. However, this concentrations did not inhibit forskolin-stimulated cAMP formation, although at supraclinical concentrations, significant inhibition was observed with an estimated IC50 of 700 μM. Conclusion. The present study indicates that a clinically relevant concentration of ketamine interacts with μ2 opioid receptors. However, no agonist activity was observed. Received for publication on September 10, 1998; accepted on January 5, 1999  相似文献   
55.
A 63-year-old man was referred to our institute for the treatment of squamous cell carcinoma of the upper lobe of his right lung. A right upper lobectomy of the lung was performed with a mediastinal lymph node dissection. The postoperative pathological examination of the dissected specimens revealed one of the superior mediastinal lymph nodes to be morbid with micrometastasis of occult thyroid cancer, while no node involvement was seen due to lung cancer. A right lobectomy of the thyroid gland with a modified radical neck dissection was done 4 years later after the confirmation of the absence of any recurrent sign of lung cancer. In the resected specimen, papillary thyroid microcarcinoma was observed with several intraglandular metastases and right regional lymph node involvement. Eight months later, a new primary lung cancer developed in the left lung, and a left upper lobectomy of the lung with a mediastinal lymph node dissection was performed. At that time, the absence of mediastinal lymph node metastasis from lung cancer or thyroid cancer was confirmed. Mediastinal lymph node involvement as the initial manifestation of occult thyroid cancer in surgical treatment for lung cancer is rare, but it is important to be aware of the possibility of incidentally detecting occult thyroid cancer in surgical dissections in this area for lung cancer. The appropriate surgical treatment should be determined while carefully considering the prognosis of the lung cancer as well as that of any coexisting malignancy.  相似文献   
56.
Ueda K  Suga K  Kaneda Y  Li TS  Ueda K  Hamano K 《The Annals of thoracic surgery》2004,77(3):1033-7; discussion 1037-8
BACKGROUND: Preoperative localization of the sentinel node basin would guide selective lymph node dissection. We tried to identify these nodal stations with indirect computed tomographic lymphography using a conventional extracellular contrast agent, iopamidol. METHODS: Eleven consecutive patients scheduled to undergo anatomic resection of suspected lung cancer, without lymphadenopathy, were given a peritumoral injection of undiluted iopamidol under computed tomography guidance, and lymphatic migration was assessed by multidetector-row helical computed tomography. RESULTS: There were no complications such as bleeding, pneumothorax, or allergic reactions. Enhanced nodes were detected in all but 1 patient who had diffuse lymph nodal calcification. Enhanced nodes were identified at 32 ipsilateral intrathoracic nodal stations (20 hilar stations and 12 mediastinal stations). The average length of the longer axis of the enhanced nodes was 4.8 mm (range, 3 to 8 mm), and the average attenuation of the enhanced nodes was 132 (range, 46 to 261) Hounsfield units. In 9 patients with confirmed lung cancer, enhanced nodes appeared at 26 nodal stations, and all apparent enhanced nodes were identified as actual lymph nodes at appropriate position during lymphadenectomy. None of the resected lymph nodes had metastatic involvement. CONCLUSIONS: Indirect computed tomographic lymphography with the peritumoral injection of iopamidol effectively depicts the drainage nodes unless they are diffusely calcified. Although further study is required, this method could guide selective lymph node dissection.  相似文献   
57.
BACKGROUND: Infection is a constant threat for the living-donor liver transplantation (LDLT) recipients, although little information is available on the occurrence of infection in such patients. METHODS: One hundred and thirteen consecutive LDLT recipients were prospectively followed for the presence of surgical site infections (SSIs) defined by CDC from April 2001 to March 2002. Risk factors for SSIs were evaluated by univariate and multivariate analysis. RESULTS: Of the 113 LDLT recipients, 42 (37%) developed 57 episodes of SSIs (21 intraabdominal abscess, 20 peritonitis, 8 cholangitis, and 9 wound). Of the 57 episodes, 29 (51%) had secondary bacteremia in 19 patients. Causative pathogens, including 17 episodes of polymicrobial infections, were 37 gram-positive cocci (17 Staphylococcus aureus, 16 Enterococcus spp., and 4 others), 40 gram-negative rods (25 Enterobacteriaceae, 13 Pseudomonas aeruginosa, and 4 others), and 2 Candida albicans. Univariate analysis revealed that ABO incompatibility and repeat surgery were associated with the development of SSIs. Also, univariate analysis revealed that adult recipients, ABO incompatibility, total operation duration, repeat surgery, and NNIS risk index were associated with secondary bacteremia. Multivariate analysis revealed that ABO incompatibility (OR: 14.0; 95% CI, 2.52-77.2) and repeat surgery (OR: 9.29; 95% CI, 2.00-43.1) were independently associated with secondary bacteremia. Eleven of the 42 cases (26%) who developed SSIs died. Of these 11 cases, 5 (45%) developed secondary bacteremia within 30 days before death. CONCLUSION: SSIs occurred in 37% of LDLT recipients. ABO incompatibility and repeat surgery increased the risk of developing SSIs with secondary bacteremia, which correlated with poor prognosis.  相似文献   
58.
Morimoto Y  Hagihira S  Koizumi Y  Ishida K  Matsumoto M  Sakabe T 《Anesthesia and analgesia》2004,98(5):1336-40, table of contents
Bispectral index (BIS) integrates various electroencephalographic (EEG) parameters into a single variable. However, the exact algorithm used to synthesize the parameters to BIS values is not known. The relationship between BIS and EEG parameters was evaluated during nitrous oxide/isoflurane anesthesia. Twenty patients scheduled for elective ophthalmic surgery were enrolled in the study. After EEG recording with a BIS monitor (A-1050) was begun, general anesthesia was induced and maintained with 0.5%-2% isoflurane and 66% nitrous oxide. Using software we developed, we continuously recorded BIS, spectral edge frequency 95% (SEF95), and EEG parameters such as relative beta ratio (BetaRatio), relative synchrony of fast and slow wave (SynchFastSlow), and burst suppression ratio. BetaRatio was linearly correlated with BIS (r = 0.90; P < 0.01; n = 253) at BIS more than 60. At a BIS range of 30 to 80, SynchFastSlow (r = 0.60; P < 0.01; n = 3314) and SEF95 (r = 0.75; P < 0.01; n = 3339) were linearly correlated with BIS. The correlation between BIS and SEF95 was significantly better than the correlation between BIS and SynchFastSlow (P < 0.01). At BIS less than 30, the burst suppression ratio was inversely linearly correlated with BIS (r = 0.76; P < 0.01; n = 65). At BIS less than 80, burst-compensated SEF95 was linearly correlated with BIS (r = 0.78; P < 0.01; n = 3404). In the range of BIS from 60 to 100, BIS can be calculated from BetaRatio. At surgical levels of anesthesia, BIS and SynchFastSlow (a parameter derived from bispectral analysis) or burst-compensated SEF95 (derived from power spectral analysis) are well correlated. However, our results show that SynchFastSlow has no advantage over SEF95 in calculation of BIS. IMPLICATIONS: The relationship between bispectral index (BIS) and electroencephalographic parameters was evaluated during nitrous oxide/isoflurane anesthesia. At surgical levels of anesthesia, BIS and the relative synchrony of fast and slow wave (a parameter derived from bispectral analysis) or burst-compensated spectral edge frequency 95% (a parameter derived from power spectral analysis) are well correlated.  相似文献   
59.
OBJECTIVES: Activation of the neuroendocrine axis in congestive heart failure is of prognostic significance, and neurohumoral blocking therapy prolongs survival. The hypothesis that surgical reduction of left ventricular size and function decreases neuroendocrine activation is less established. We evaluated the neurohormonal response to left ventricular reconstruction surgery in ischemic cardiomyopathy. METHODS: Norepinephrine, plasma renin activity, and angiotensin II were measured in 10 patients before and 12 months after left ventricular reconstruction. In an additional 5 patients, brain natriuretric peptide was measured before and 3 months postoperatively. Three-dimensional cardiovascular imaging was used to assess ejection fraction and left ventricular end-diastolic volume index. RESULTS: Concurrent with improvements of New York Heart Association functional class (2.9 +/- 0.5 preoperatively vs 2.0 +/- 0.4 postoperatively, P <.001), ejection fraction (23.9% +/- 6.6% vs 36.2% +/- 6.2%, P <.01), and left ventricular end-diastolic volume index (140.8 +/- 33.8 mL/m(2) vs 90.6 +/- 18.3 mL/m(2), P <.01), considerable reductions were observed for median plasma profiles of norepinephrine (562.0 pg/mL vs 319.0 pg/mL, P <.05), plasma renin activity (5.75 microg/L/h vs 3.45 microg/L/h, P <.05), angiotensin II (41.0 ng/mL vs 23.0 ng/mL, P =.051), and brain natriuretric peptide (771.0 pg/mL vs 266.0 pg/mL, P <.05). The more plasma renin activity or angiotensin II decreased after left ventricular reconstruction, the higher was the increase in ejection fraction (R = -.745, P <.05 [plasma renin activity]; R = -.808, P <.05 [angiotensin II]). CONCLUSIONS: Surgical improvements of ejection fraction and left ventricular end-diastolic volume index by left ventricular reconstruction were accompanied by improvement of both the neuroendocrine activity and the functional status in patients with congestive heart failure. Whether this favorable neurohormonal response is predictive of an improved survival requires further evaluation.  相似文献   
60.
The abnormal origin of the left circumflex artery from the proximal right coronary artery (RCA) is considered a coronary artery anomaly. Most of the coronary artery anomalies are diagnosed incidentally by coronary artery angiography, and several considerations are needed to avoid fatal complications in patients undergoing aortic valve replacement (AVR). We report a case of AVR with anomalous origin of the left circumflex artery from a common ostium of the RCA, and discuss the use of a smaller prosthesis to avoid compression of the anomalous left circumflex artery.  相似文献   
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