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71.
OBJECTIVE: Our long-term results with anterior venous sinus plication (AVSP) for femoral vein reconstruction will be presented. PATIENTS AND METHODS: Between 1986 and 2001 we treated 2 100 patients in our hospital for chronic venous insufficiency. In 3.3 % of the patients (n = 70) an AVSP of the target valve, which is the highest valve of the femoral vein distally of the profundal vein branch was carried out. 50 patients could be followed for 2-15 (average 4.6) years postoperatively by phlebographic control. RESULTS: Four recovery patterns after valve repair were seen on venography. The most typical type was the plicated site stop seen in 22 of 50 patients (44 %). Here the venous reflux was stopped at the plicated site directly. The clinical results were good or excellent for all patients. No patient underwent a second procedure for recurrence of the symptoms. A profundal femoral vein reflux did not negatively influence patient outcome. CONCLUSION: AVSP is an excellent method of valve repair in strictly selected patients with chronic venous insufficiency (= no postthrombotic syndrome, no thrombotic occlusion of the femoral veins). Long-term results up to 15 years were highly satisfactory.  相似文献   
72.
Gene expression profile of renal proximal tubules regulated by proteinuria   总被引:13,自引:0,他引:13  
BACKGROUND: Proximal tubules activated by reabsorption of protein are thought to play significant roles in the progression of kidney diseases. Thus, identification of genes related to proteinuria should provide insights into the pathological process of tubulointerstitial fibrosis. METHOD: Gene expression profiles were constructed by means of direct sequencing procedures to identify genes induced in the mouse kidney proximal tubules (PT) exposed to proteinuria. RESULTS: By comparing the gene expression of control PT to that of disease model PT, the abundantly expressed genes in control PT were down-regulated presumably because of potentially toxic effects of proteinuria. From the more than 1000 up-regulated genes, an immunity related gene, thymic shared antigen-1 (TSA-1), and a novel gene, GS188, were selected for further characterization. The increased expression of TSA-1, a member of the Ly-6 family, and of GS188 in response to proteinuria was confirmed by Northern analysis, immunohistochemistry, in situ hybridization and laser microdissection along with real-time PCR analysis. Full length cloning of GS188 identified it as a family member of LR8 that was reported to express predominantly in fibroblasts. CONCLUSIONS: The gene expression profiles showed that the expression patterns in PT were changed dramatically by proteinuria. The profiles include novel genes that should be further characterized to aid the understanding of the pathophysiology of progressive kidney diseases.  相似文献   
73.
Efficacy and safety of on-pump beating heart surgery for valvular disease   总被引:12,自引:0,他引:12  
BACKGROUND: This study was conducted to assess the efficacy and applicability of on-pump beating heart valvular operations using retrograde coronary sinus perfusion. METHODS: A prospective, randomized study was conducted. A total of 50 patients participated in this study after having been allocated to one of two groups. On-pump beating heart valvular operations using retrograde coronary sinus perfusion as myocardial protection were performed in 25 patients (beating heart procedure group: aortic = 8 patients, mitral = 15 patients, double = 2 patients). Twenty-five patients underwent conventional valvular operation using retrograde continuous warm blood cardioplegia (conventional procedure group: aortic = 9 patients; mitral = 13 patients; double = 3 patients). The remaining operative variables and early outcomes of these procedures were compared. In the beating heart procedure group, myocardial tissue oxygen was measured by near infrared spectroscopy, and partial oxygen pressure of coronary sinus perfusion was also measured. RESULTS: The visual field of the on-pump beating heart was equal to that of conventional valvular operation, and technical accuracy was not compromised. In the beating heart procedure group, tissue oxygen saturation was maintained at 79% +/- 2%, and partial oxygen pressure of coronary sinus perfusion blood and returned blood were maintained at 383 +/- 29 mm Hg and 38 +/- 2 mm Hg, respectively. Postoperative peak creatine kinase-MB (measured every 3 hours postoperatively) and peak troponin T concentrations were significantly lower than those of conventional procedures (17.5 +/- 7.8 vs 32.1 +/- 9.3 IU/L and 0.12 +/- 0.04 vs 0.21 +/- 0.06 ng/mL, respectively; p < 0.05). There was no operative mortality and no major complications. CONCLUSIONS: On-pump beating heart valvular operation is a good surgical option, and has advantages because conditions for the heart are more physiologic with beating tonus than with cardioplegia.  相似文献   
74.
To investigate whether the use of a stentless porcine aortic xenograft can be an alternative for right ventricular outflow tract (RVOT) reconstruction during the Ross procedure, 9 patients underwent the Ross procedure and RVOT reconstruction with a stentless xenograft since January 2000. After the aortic valve was replaced with a pulmonary autograft, a stentless xenograft with a xeno- pericardial roll was implanted in the RVOT. One patient required subsequent aortic valve replacement because of severe regurgitation of the pulmonary autograft. All patients recovered well from the operation. The right ventricle-pulmonary arterial pressure gradient was 18 +/- 7 mm Hg at discharge and was not significantly increased during the 2-year follow-up period. Although 1 patient died of ventricular arrhythmia 5 months after, his cardiac function was normal, and transpulmonary valve pressure was 19 mm Hg in the follow-up. The other 7 patients are currently in New York Heart Association functional Class I. Although long-term follow-up is required to explain the durability, the stentless xenograft with a pericardial roll is considered to be an alternative for reconstruction of the RVOT within 2 years after the Ross procedure.  相似文献   
75.
RATIONALE AND OBJECTIVES: To examine the correlation between the echogenicity and the components of atherosclerotic plaques in rabbit. METHODS: The atherosclerotic plaque formation in the abdominal aortas of hyperlipidemic or normolipidemic rabbits was stimulated by inserting polyethylene tubing. Intravascular ultrasound (30-MHz, 4.5 F catheter) investigation was performed at locations in the vessel. The intravascular ultrasound images of the plaques were evaluated and compared with the histologic findings. RESULTS: Ultrasound images delineated areas showing hyperechoic or hypoechoic ultrasound beams in the plaques. Histologic studies revealed that the hyperechoic areas were closely associated with a dense fibrous extracellular matrix, whereas the hypoechoic areas corresponded to lesions showing a marked accumulation of foamy macrophages or proteoglycan-rich loose myxoid extracellular matrix with smooth muscle cell proliferation. CONCLUSION: A good correlation between ultrasound images and histologic features was observed. These results suggest that intravascular ultrasound imaging could provide useful information for assessing the tissue characteristics of atherosclerotic lesions.  相似文献   
76.
Nystagmus is a rhythmical rotation of the eyeball. Its characteristics can be defined mathematically by the axis of rotation and the angular velocity around this axis. We analysed the axis of rotation for the nystagmus in benign paroxysmal positional vertigo (BPPV) to elucidate its pathophysiology. Thirteen patients with typical unilateral BPPV participated in the present study. The axis of rotation for the nystagmus was calculated from images recorded on digital videotape with an infrared CCD camera, using an algorithm that we developed. The patients' responsiveness to Semont's liberatory maneuver was also assessed. The results showed that patients could be assigned to one of two groups based on the rotation axis of the nystagmus. In one group of patients (n = 7; Group A), the axis of rotation was almost vertical to the plane containing the posterior semicircular canal (PSC) on the presumed affected side. In the other group of patients (n = 6; Group B), it was clustered around the naso-occipital axis. These results suggest that in the patients in Group A the responsible lesion is confined to the PSC, whereas the pathogenesis underlying the conditions in those in Group B is considered to be more complicated. This speculation was reinforced by the difference in responsiveness to Semont's liveratory maneuver. All of the patients in Group A showed remission of vertigo within 10 days (mean, 2.4 days) after onset of treatment using Semont's liberatory maneuver, whereas the patients in Group B required much longer periods of time for remission to occur (mean, 25.7 days). Our findings lead to the conclusion that by considering the spatial orientation of individual semicircular canals, in the patients in Group B the pathophysiology is not confined to the PSC, but most probably all three semicircular canals are involved. Received: 16 January 2002, Received in revised form: 22 May 2002, Accepted: 6 June 2002 Correspondence to Yujiro Hayashi, MD  相似文献   
77.
Antibody (Ab) responses and protection against influenza virus infection in mice immunized intranasally with hemagglutinin (HA) or neuraminidase (NA) purified from the A/Beijing/262/95 (A/Beijing) (H1N1) virus were compared among B10 congenic mouse strains. Mice were immunized intranasally with 0.1, 0.3 or 1microg of HA or NA together with the cholera toxin adjuvant, and then boosted intranasally with 0.3 microg of the adjuvant-combined HA or NA 4 weeks later. Two weeks after the second immunization, the mice were challenged by an infection of the upper respiratory tract with the homologous virus. After 3 days, nasal wash and serum specimens were collected for virus and Ab titration. The HA immunization induced HA-specific IgG Ab responses against A/Beijing HA, which depended on the H-2 haplotype of the strain: The B10.A (H-2(a)), B10.D2 (H-2(d)), B10.BR (H-2(k)) and B10 (H-2(b)) strains were the highest, high, intermediate and low responders, respectively. The nasal IgA responses were induced in the B10.A, B10.D2 and B10.BR strains, but not in the B10 strain. In parallel with Ab responses, the B10.A, B10.BR and B10.D2 strains were conferred significant protection at any dose of primary immunization, but the B10 strain was provided protection only at 1microg of HA. On the other hand, the NA immunization induced NA-specific Ab responses, which depended on the the H-2 haplotype of the strain: the B10.A, B10.D2, B10 and B10.BR strains were the highest, high, intermediate and low responders, respectively. In parallel with Ab responses, all the strains were conferred significant protection at any dose of primary immunization. These results indicate that the MHC-restricted responsiveness of mice to HA is different from that to NA, suggesting that the use of high-HA dose or NA as a component of the nasal influenza A (H1N1 subtype) virus vaccine improves the protective efficacy against influenza among low responder populations.  相似文献   
78.
We attempted to produce a monoclonal antibody (MAb) against the active site of native thrombin. Bovine thrombin was treated with diisopropyl fluorophosphate, and prepared diisopropylphosphoryl-thrombin was used for the immunization to BALB/c mice. Spleen cells of immunized mice were hybridized with mouse myeloma cells P3U1, and a hybridoma clone CC2, which produced a MAb against bovine thrombin was established. The MAb produced by hybridoma clone CC2 (MAb(CC2)), consisting of IgG(1) and kappa light chain, was purified using protein A affinity chromatography. Purified MAb(CC2) prolonged the fibrin forming time of bovine thrombin and inhibited the release of fibrinopeptide A from rabbit fibrinogen. In addition, it was found that argatroban partially, but competitively, interfere the binding between MAb(CC2) and bovine thrombin. It was then considered that MAb(CC2) would bind to the molecular structure associating primary specific pocket in the active site of bovine thrombin.  相似文献   
79.
Intratracheal administration of platelet-activating factor (PAF) to dogs, baboons, and humans has been shown to induce hyperreactivity of the airways and contraction of the smooth muscle. However, it has not yet been reported whether intratracheal administration of PAF to rats induces hyperreactivity. In the present study, the authors estimated the respiratory resistance of rats during intratracheal administration of PAF in order to evaluate the reactivity of the airways to PAF. In both the nonsensitized group and the sensitized group of rats, intratracheal administration of PAF induced an increase in respiratory resistance. The results obtained clarify that responsiveness to PAF exists in the airways of rats.  相似文献   
80.
Increased heterogeneity of chromosome 17 aneuploidy in endometriosis   总被引:5,自引:0,他引:5  
OBJECTIVE: Endometriosis is a complex gynecologic disorder that may display features similar to malignancy, including aggressive growth and localized invasion of the myometrium or spread to various organs outside the uterus. Molecular studies of cancer have demonstrated that genomic instability involving chromosome 17 plays a role in the development and progression of various tumor types. These involve gain and/or loss, deletions, and mutations of candidate tumor suppressor genes (eg, BRCA1 and p53 ) on chromosome 17. STUDY DESIGN: We used a 2-color fluorescence in situ hybridization method for analysis of endometriotic and normal archival tissue. Centromere-specific and locus-specific p53 probes localized to chromosome 17 were selected to study 8 patients with late-stage (severe) endometriosis. Single cells localized to endometriotic lesions or normal endometrial glands were analyzed and identified as normal or abnormal on the basis of the distribution of fluorescence in situ hybridization signals. RESULTS: Overall, chromosome 17 aneuploidy was significantly greater (P <.05) in the endometriosis specimens (mean of 65%) than in normal endometrial cells (mean of 25%). No significant difference (P =.1071) in the distribution of fluorescence in situ hybridization signals was observed among the 5 normal endometrial specimens. However, significant differences (P <. 0001) were observed between the 8 endometriosis tissue specimens. CONCLUSION: We found increased heterogeneity of chromosome 17 aneuploidy in endometriosis. These findings support a multistep pathway involving somatic genetic alterations in the development and progression of this common disease.  相似文献   
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