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951.
Reeves‐Daniel A, Freedman BI, Assimos D, Hartmann EL, Bleyer A, Adams PL, Westcott C, Stratta RJ, Rogers J, Farney AC, Daniel KR. Short‐term renal outcomes in African American and Caucasian donors following live kidney donation.
Clin Transplant 2009 DOI: 10.1111/j.1399‐0012.2009.01170.x
© 2009 John Wiley & Sons A/S. Abstract: Introduction: Although African Americans (AA) are considered higher risk kidney donors than Caucasians, limited data are available regarding outcomes of AA donors. Methods: We performed a single‐center retrospective review of all kidney donors from 1993 to 2007 and evaluated race/ethnic differences in post‐donation changes in renal function, incident proteinuria, and systolic blood pressure (SBP) using linear mixed models. Results: A total of 336 kidney donors (63 AA, 263 Caucasian, 10 other) were evaluated. Before donation, AA had higher serum creatinine concentrations, estimated glomerular filtration rate (GFR) values, and SBP levels than Caucasians. No significant changes in SBP or renal function were observed between the two groups within the first year after donation, although results were limited by incomplete follow‐up. Conclusion: AA had higher pre‐donation serum creatinine, GFR, and SBP values compared to Caucasians; however, the degree of change in renal function and blood pressure did not differ between groups following kidney donation. Although long‐term studies are needed, our study suggests that AA and Caucasians experience similar short‐term consequences after donation. The incomplete data available on donor outcomes in our center and in prior publications also indicates a global need to implement systems for structured follow‐up of live kidney donors.  相似文献   
952.
Lung transplantation (LTx) is a therapeutic option for patients with end-stage lung disease. However, the mortality rate of patients on the waiting list is high. The purpose of this study was to examine the prognostic value of cardio-pulmonary hemodynamics for death in patients awaiting LTx. Retrospectively, 177 patients with advanced lung disease accepted for LTx at Sahlgrenska University Hospital from January 1990 through December 2003 were studied. Patient demographics, pulmonary function tests, gas exchange and hemodynamic variables were included in the analysis. Death while awaiting LTx was the primary endpoint for all analyses. Mean age was 49 +/- 9 years. Main diagnoses were alpha 1 antitrypsin deficiency (n = 56), chronic obstructive pulmonary disease (n = 61), cystic fibrosis (n = 14) and interstitial lung disease (n = 46). Thirty patients died (17%). LTx was performed in 143 cases. By univariate analyses, forced vital capacity (FVC) % of predicted, pulmonary vascular resistance (PVR) and diagnosis were associated with risk for death. In multivariate analysis PVR (HR, 1.22; 95% CI, 1.06-1.41; P = 0.006) and FVC% of predicted (HR, 0.97; 95% CI, 0.94-0.99; P = 0.01) were independently associated with death. Patients with increased PVR and a lower FVC % of predicted awaiting LTx should be considered for a higher organ allocation priority. Assessment of pulmonary hemodynamics needs to be considered during evaluation for LTx.  相似文献   
953.
To analyze human herpesvirus 6 (HHV-6) infection in adult living related liver transplantation, we performed a virological analysis, including viral isolation, serological assay, and real-time polymerase chain reaction, of serially collected blood samples from 67 recipients. In addition, cytokine levels were measured to determine their role in viral reactivation. HHV-6 was isolated from only 4 recipients (6.0%), and viral DNA was detected in 15 (22.4%) of the 67 recipients. A significant increase in HHV-6 immunoglobulin G antibody titers was observed in 19 (28.4%) of the 67 recipients. Finally, 26 recipients (38.8%) had HHV-6 reactivation 2-6 weeks after transplantation. HHV-6 associated clinical features were analyzed in the 17 recipients presenting with either viremia or DNAemia. Two recipients with viremia and 3 recipients with DNAemia had unexplained fever at the time of viral infection. An increase in aminotransferase levels was observed in 2 recipients with viremia and 3 recipients with DNAemia. Recipients with liver cirrhosis caused by hepatitis B virus or hepatitis C virus infection as the underlying disease were more likely to have HHV-6 infection (P = 0.025). Mortality at the last follow-up in recipients with HHV-6 reactivation was significantly higher than in those without viral reactivation (P = 0.0118). Plasma interleukin-6 levels were significantly higher in the recipients with HHV-6 viremia than in the recipients without viremia at 4 weeks post-transplant (P = 0.0411). Moreover, tumor necrosis factor alpha levels were also higher in recipients with HHV-6 viremia (P < 0.0001) or reactivation (P = 0.0011) than in recipients without viremia or reactivation 4 weeks post-transplant.  相似文献   
954.
BACKGROUND: We evaluated the importance and mechanism of graft and host accommodation in hamster-to-rat cardiac xenotransplantation models. METHODS: To evaluate graft accommodation, accommodated hamster grafts (Group 2) were transplanted to na?ve host rats treated with FK506, and compared with na?ve hamster grafts (Group 1). To evaluate host accommodation, three groups were evaluated: naive hamster hearts were transplanted to na?ve hosts treated with FK506 (Group 3: 0.5 mg/kg, Group 4: 1.0 mg/kg) and splenectomy, and compared with accommodating hosts (Group 5) with FK506 0.5 mg/kg and splenectomy. We examined graft survival, histopathology, antihamster antibodies and B-1 cells in blood. RESULTS: Graft survival in Group 2 (3.4+/-0.9 days) was not significantly different from that in Group 1 (2.8+/-0.4 days). Graft survival in Groups 4 and 5 (>30 days) was significantly prolonged compared with that in Group 3 (6.0+/-0.7 days). Histopathology of Groups 1-3 showed humoral rejection, whereas Groups 4 and 5 showed normal histology and expression of protective genes. In Groups 1-3, antihamster immunoglobulin (Ig) M and B-1 cells increased significantly compared to Groups 4 and 5, where IgM and B-1 cells remained low or were reduced. CONCLUSIONS: Host accommodation was more important than graft accommodation. Accommodating grafts expressing protective genes were rejected with an elevation of both IgM and B-1 cells. In accommodated hosts, both IgM and B-1 cells decreased, suggesting that B-1 cells may be responsible for the production of antihamster antibodies. These results suggest that sufficient suppression of B-1 cells, resulting in decreased titers of antihamster antibodies, may play an important role in host accommodation.  相似文献   
955.
PURPOSE: There is increasing concern about the risks of radiation exposure with the advent of new, more complex imaging modalities. For example, computed tomography (CT), with its obvious advantages, is being more commonly used in the investigation of acute flank pain. The likely radiation exposure a patient can expect during a single complete urinary stone episode was studied. PATIENTS AND METHODS: The hospital records of 60 consecutive unselected patients who had become or were rendered stone-free were studied. The effective radiation doses in milliSieverts (mSV) associated with diagnostic imaging modalities such as intravenous urogram studies and CT scans were calculated for St. George's Hospital. By combining these with the published effective doses for interventional examinations, the total effective dose over an entire stone episode was derived. RESULTS: There were a total of 60 patients with 68 stones (15 renal, 9 in the upper, 12 in the middle, and 32 in the lower ureter), with a median stone burden of 4 mm. Thirty-two patients had procedures performed, including extracorporeal shockwave lithotripsy SWL. Total effective doses ranged from 1.18 to 37.66 mSv (median 5.3 mSv; 95% CI of the median 4.13, 7.61). Renal and proximal ureteral stones resulted in the highest radiation exposures. CONCLUSION: In this study the median radiation dose per stone episode was calculated at 5.3 mSv, with higher doses in those with renal stones and those who required CT scans and other interventions. Monitoring and reduction of radiation exposure is advised for all patients presenting with urolithiasis.  相似文献   
956.
BACKGROUND: Renal transplantation is a definitive therapeutic modality in end-stage renal disease (ESRD). Most ESRD patients in Japan experience dialysis prior to renal transplantation. The present study was undertaken to examine the usefulness of pre-emptive renal transplantation (PET). METHODS: Between 1987 and 1998, 255 renal transplantations were carried out by the authors. Among those consecutive cases, 10 were cases of PET. In nine pediatric cases, demographics, graft and patient survival, height growth and benefits from successful transplantation were studied and compared with age-matched dialyzed transplantation controls. RESULTS: All transplantation was living-related. There was a disparity of causes of ESRD between the two groups. In PET, acquired renal deterioration due to a congenital lower urinary tract disorder was the major cause. Graft and patient prognosis was favorable in both groups. Growth retardation in PET patients under 15 years of age was significantly less apparent at the time of transplantation and after 3 years compared to the control. The benefits from transplantation were different in the two groups. Most PET patients felt an improvement of their physical condition; however, all of the control patients felt that the major boon was the freedom from the restriction of the daily diet and time for dialysis. CONCLUSION: In pediatric renal transplantation, short-term preceding dialysis does not have a detrimental effect, but PET could benefit ESRD patients by maintaining their quality of life. Moreover, PET minimizes the production of renal dwarfism in prepubertal children. Thus, PET should be taken into consideration in the choice of renal replacement therapy.  相似文献   
957.
Transcatheter arterial embolization (TAE) represents the primary, and often definitive, mode of therapy for bleeding splanchnic artery pseudoaneurysms (PSA). Nevertheless, a number of complications associated with this procedure have been described. We report herein the case of a 59-year-old man with chronic pancreatitis who was referred to us with hematemesis and hemorrhagic shock. Computed tomography revealed a splenic artery PSA bleeding into a pancreatic pseudocyst, and TAE was performed using steel-wire coils, placed inside the aneurysmal cavity, which resulted in the immediate cessation of bleeding. However, several weeks later some of the coils were found to have dislodged through a gastropseudocystic fistula. Furthermore, an early gastric cancer was incidentally found proximal to the fistula. We finally performed open surgery to treat both disorders; primarily for the gastric cancer, but also for the pseudocyst and fistula, with the intermittent discharge of the steel-wire coils. To our knowledge, migration into the stomach of steel-wire coils after TAE has not been described before. It is generally believed that the embolization procedure should occlude normal portions of the artery both distal and proximal to the PSA with embolization materials. By occluding the PSA in this way, the subsequent migration of steel-wire coils into the pseudocyst and stomach might have been prevented in our patient. Received: July 31, 2000 / Accepted: November 20, 2000  相似文献   
958.
The increase in the incidence of colorectal cancer (CRC) is higher for proximal than for distal tumors. As microsatellite instability (MSI) is a feature of proximal tumors, we hypothesize that an increase in MSI tumors may account for the age‐related proximal shift in CRC. Methods: A representative sample of 230 CRCs from 3 age groups was selected from a CRC database. MSI was determined by PCR. MLH1 and MSH2 expression was determined by immunohistochemistry, and the methylation of the MLH1 gene promotor (PM) by methylation‐specific PCR. Results: MSI tumors became more frequent (p < 0.01 chi square) and more proximal in distribution (p = 0.01 loglinear) in the oldest age group. MSI was associated with loss of expression of MSH2 in the young age group. PM and inactivation of MLH1 increased with age. Conclusion: MSI tumors became more frequent and proximal in older patients. This trend was associated with differences in the underlying mechanisms responsible for the MSI phenotype.  相似文献   
959.
We report a case of Bland-White-Garland syndrome with advanced age. The patient, a 67-year-old women, presented with a history of congestive heart failure. Coronary catheterization revealed an anomalous origin of the left coronary artery (LCA) from the trunk of the pulmonary artery and huge right coronary aneurysm. Myocardial single photon emission computed tomography (SPECT) showed previous myocardial infarction with reversible ischemia in left anterior descending (LAD) region. We performed LCA direct closure and coronary artery bypass graft. The patient recovered uneventfully without signs of ischemia. Although a bypass graft was patent, left ventricular function had not been improved immediately probably due to the coronary flow pattern changes.  相似文献   
960.
The association between osteoporosis and cardiovascular diseases has been demonstrated. Higher cardiovascular risk has also been correlated with vertebral fractures. However, the association between osteoporotic vertebral fracture and the possibly higher risk of stroke remains uncertain. This study aimed to evaluate the incidence, risk, and type of stroke in patients with osteoporotic vertebral fracture. Patients with osteoporotic vertebral fracture were identified (n = 380) and 10 age‐ and sex‐matched controls per case (comparison group, n = 3795) were chosen from a nationwide representative cohort of 999,997 people from 1998 to 2005. Both groups were followed‐up for stroke events for 3 years, matched by propensity scores with adjustments for covariates such as comorbidities (ie, hypertension, diabetes, arrhythmia, or coronary heart diseases) and exposure to medications (ie, aspirin, lipid lowering drug, or nitrates), and assessed by Kaplan‐Meier and Cox regression analyses. The incidence rate of stroke in the osteoporotic vertebral fracture group (37.5 per 1000 person‐years; 95% confidence interval [CI], 27.5–51.2) was significantly higher than in the comparison group (14.0 per 1000 person‐years; 95% CI, 12.0–16.4, p < 0.001). Stroke was more likely to occur in the osteoporotic vertebral fracture patients than in the normal controls (crude hazard ratio [HR] 2.68, 95% CI 1.89–3.79, p < 0.001; adjusted HR 2.71, 95% CI 1.90–3.86, p < 0.001). In conclusion, patients with osteoporotic vertebral fracture have a higher risk of stroke (ie, both ischemic and hemorrhagic) and require stroke prevention strategies. © 2013 American Society for Bone and Mineral Research.  相似文献   
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