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41.
BACKGROUND: Coronary artery disease (CAD) is the leading cause of mortality after the first year of heart transplantation. End-stage renal failure (ESRF) is more frequent because of long-term survival. Impact of ESRF on cardiac mortality in heart transplant patients is unappreciated. The hypothesis of accelerated CAD in uremic patients has been suggested. METHODS: In Pitié La Salpêtrière hospital, 1211 heart transplants have been performed between 1982 and 2001. Thirty-three patients have reached ESRF. A case-control study was performed to identify risk factors responsible for ESRF and to appreciate the impact of ESRF on cardiac mortality. RESULTS: In cases at 6 months, serum creatinine tended to be higher (159 +/- 31 micromol/L vs. 141 +/- 44 micromol/L, p = 0.06) and cyclosporine (CSA) dosage (mg/kg) was significantly lower (5.4 +/- 1.8 mg/kg vs. 7.7 +/- 2.7 mg/ kg, p = 0.002). Mean triglyceride level after transplantation until dialysis was significantly lower in cases (2.18 +/- 0.82 mmol/L vs. 1.48 +/- 0.62 mmol/L, p = 0.002). In cases and controls, cardiac mortality was responsible for 67% (10 of 15) and 38% (three of eight) of all deaths, respectively. High triglyceride level (> or = 2 mmol/L) was associated with cardiac mortality [p < 0.03, hazard ratio (HR) = 3.89]. Kaplan Meier cardiac free survival rates were significantly lower in cases than in controls (p < 0.03). CONCLUSION: These data suggest that CSA nephrotoxicity could result from individually determined susceptibility and that hypertriglyceridemia may have a negative impact on renal function and cardiac mortality. The risk of cardiac mortality is increased in heart transplant patients with ESRF. The hypothesis of accelerated atherosclerosis in ESRF patients after heart transplantation leading to higher cardiac mortality incidence needs further study.  相似文献   
42.
PURPOSE: To determine whether the blood flow abnormalities frequently associated with arteriovenous malformations (AVMs) can alter functional magnetic resonance (MR) imaging evaluation of language lateralization and whether reorganization of language function occurs in patients with brain AVMs. MATERIALS AND METHODS: Eleven patients with left-hemisphere brain AVMs and 10 age-matched control subjects were examined with 1.5-T blood oxygen level-dependent (BOLD) functional MR imaging. Verbal fluency, sentence repetition, and story listening tasks were performed. The functional MR imaging laterality index in the frontal and temporal lobes was defined as the (L - R)/(L + R) ratio, where L and R are the numbers of activated pixels in the left and right hemispheres, respectively. Statistical analyses were performed with Wilcoxon signed rank, Fisher exact, and Kruskal-Wallis tests. RESULTS: Control subjects had left-sided language dominance, although symmetric pixel counts were observed in the frontal lobes in two subjects and in the temporal lobes in one subject. Six patients had left-sided language dominance similar to that observed in control subjects. Five of these patients had AVMs outside frontal or temporal language areas, without flow abnormalities. Five patients had abnormally right-sided asymmetric indexes (below mean control subject value - 2 SDs), which suggested language reorganization (P <.05). Results of Wada examination and/or postembolization functional MR imaging performed in two of these patients showed that the abnormal laterality indexes were at least partly due to severe flow abnormalities that impaired detection of BOLD MR imaging signal intensity. CONCLUSION: These data suggest that flow abnormalities may interfere with language lateralization assessment with functional MR imaging.  相似文献   
43.
Six patients with giant platelet syndrome were examined: four with Bernard-Soulier syndrome (two were asplenic); one with hereditary thrombopathic thrombocytopenia; and one with May-Hegglin anomaly. Autologous platelets were labelled with In-111-oxine and in vivo redistribution and sites of sequestration measured with quantitative imaging. In Bernard-Soulier syndrome platelet survival was normal or moderately shortened; platelet turnover was decreased only in the two patients with thrombocytopenia. In the patients with thrombopathia or May-Hegglin anomaly, platelet survival and turnover was moderately decreased. In those patients with normal-sized spleens, the mean splenic platelet pool consisted of 35.5% of the platelet mass, i.e. normal. The intrasplenic transmit time of the megathrombocytes was prolonged. Splenic blood flow was within normal limits. There was a marked accumulation of platelets in the liver at equilibrium: 15.5-58.8% of whole body radioactivity (normal 9.6 +/- 1.2%). This finding is unexplained. The final sites of sequestration of platelets were mainly in the liver and spleen, similar to that seen in normal subjects. We conclude that there is no inverse relationship between cell size and splenic platelet transit time. Platelet size therefore does not determine the size of the splenic platelet pool. The size of the platelets also does not seem to affect the sites of sequestration at the end of their life span.  相似文献   
44.
Jean-Jacques Parienti, MD, DTM&H; Marina Thirion, MD; Bruno Mégarbane, MD, PhD; Bertrand Souweine, MD, PhD; Abdelali Ouchikhe, MD; Andrea Polito, MD; Jean-Marie Forel, MD; Sophie Marqué, MD; Benoît Misset, MD; Norair Airapetian, MD; Claire Daurel, MD; Jean-Paul Mira, MD, PhD; Michel Ramakers, MD; Damien du Cheyron, MD, PhD; Xavier Le Coutour, MD; Cédric Daubin, MD; Pierre Charbonneau, MD; for Members of the Cathedia Study Group

JAMA. 2008;299(20):2413-2422.

Context  Based on concerns about the risk of infection, the jugular site is often preferred over the femoral site for short-term dialysis vascular access.

Objective  To determine whether jugular catheterization decreases the risk of nosocomial complications compared with femoral catheterization.

Design, Setting, and Patients  A concealed, randomized, multicenter, evaluator-blinded, parallel-group trial (the Cathedia Study) of 750 patients from a network of 9 tertiary care university medical centers and 3 general hospitals in France conducted between May 2004 and May 2007. The severely ill, bed-bound adults had a body mass index (BMI) of less than 45 and required a first catheter insertion for renal replacement therapy.

Intervention  Patients were randomized to receive jugular or femoral vein catheterization by operators experienced in placement at both sites.

Main Outcome Measures  Rates of infectious complications, defined as catheter colonization on removal (primary end point), and catheter-related bloodstream infection.

Results  Patient and catheter characteristics, including duration of catheterization, were similar in both groups. More hematomas occurred in the jugular group than in the femoral group (13/366 patients [3.6%] vs 4/370 patients [1.1%], respectively; P = .03). The risk of catheter colonization at removal did not differ significantly between the femoral and jugular groups (incidence of 40.8 vs 35.7 per 1000 catheter-days; hazard ratio [HR], 0.85; 95% confidence interval [CI], 0.62-1.16; P = .31). A prespecified subgroup analysis demonstrated significant qualitative heterogeneity by BMI (P for the interaction term < .001). Jugular catheterization significantly increased incidence of catheter colonization vs femoral catheterization (45.4 vs 23.7 per 1000 catheter-days; HR, 2.10; 95% CI, 1.13-3.91; P = .017) in the lowest tercile (BMI <24.2), whereas jugular catheterization significantly decreased this incidence (24.5 vs 50.9 per 1000 catheter-days; HR, 0.40; 95% CI, 0.23-0.69; P < .001) in the highest tercile (BMI >28.4). The rate of catheter-related bloodstream infection was similar in both groups (2.3 vs 1.5 per 1000 catheter-days, respectively; P = .42).

Conclusion  Jugular venous catheterization access does not appear to reduce the risk of infection compared with femoral access, except among adults with a high BMI, and may have a higher risk of hematoma.

Trial Registration  clinicaltrials.gov Identifier: NCT00277888

  相似文献   

45.
PURPOSEWe aimed to evaluate the prostate volumes calculated as recommended in the PI-RADS v2 and PI-RADS v2.1 guidelines, intraobserver and interobserver variability, and the agreement between the two measurement methods.METHODSProstate mpMRI examinations of 114 patients were evaluated retrospectively. T2-weighted sequences in the axial and sagittal planes were used for the measurement of the prostate volume. The measurements were performed by two independent observers as recommended in the PI-RADS v2 and PI-RADS v2.1 guidelines. Both observers conducted the measurements twice and the average values were obtained. In order to prevent bias, the observers carried out measurements at one-week intervals. In order to assess intraobserver variability, observers repeated the measurements again at one-week intervals. The prostate volume was calculated using the ellipsoid formula (W×H×L×0.52).RESULTSIntraclass correlation coefficient (ICC) revealed almost perfect agreement between the first and second observers for the measurements according to both PI-RADS v2 (0.93) and PI-RADS v2.1 (0.96) guidelines. The measurements were repeated by both observers. According to the ICC values, there was excellent agreement between the first and second measurements with respect to both PI-RADS v2 and PI-RADS v2.1 for first (0.94 and 0.96, respectively) and second observer (0.94 and 0.97, respectively). For both observers, the differences had a random, homogeneous distribution, and there was no clear relationship between the differences and mean values.CONCLUSIONThe ellipsoid formula is a reliable method for rapid assessment of prostate volume, with excellent intra- and interobserver agreement and no need for expert training. For the height measurement, the recommendations of the PIRADS v2.1 guideline seem to provide more consistently reproducible results.

The prostate gland is one of the organs for which the disease incidence and prevalence in men increases with age. Prostate volume (PV) has an important role in the evaluation and management of both malignant and benign prostate diseases (13). In benign prostatic hyperplasia (BPH), prostate volume is used to decide upon treatment and evaluate response to medical therapy (35). In the diagnosis of prostate cancer, one of the important markers is prostate-specific antigen (PSA), but it has low specificity, and therefore PSA derivatives are used to increase its specificity. One example is PSA density, which is obtained by dividing the PSA value by PV. In the treatment of prostate cancer, PV is important, and the effectiveness of brachytherapy decreases in prostates with a volume greater than 50 mL (6). Furthermore, PV is used to identify appropriate patients for brachytherapy and select the number of radioactive seeds, and also determine fractionation for external beam radiation, radical prostatectomy operating planning and continence rate counseling, and focal therapy candidacy preparation (7, 8). For these reasons, it is vital to accurately calculate PV.There are many methods that can be used to calculate PV, with the ellipsoid formula being one of the most preferred since it is easy to apply and highly time-efficient (14, 9). Many studies have shown that this method has high accuracy due to the elliptic shape of the prostate (1, 2, 1013). The ellipsoid formula is obtained by multiplying the height (anterior-posterior), width (medio-lateral) and length (cranio-caudal) values of the prostate by 0.52. These measurements can be performed by transrectal ultrasonography (TRUS) or magnetic resonance imaging (MRI). TRUS has certain disadvantages, such as being operator-dependent and susceptible to sonographic artifacts (14). MRI, which has become increasingly popular in recent years, allows for an accurate definition of the prostate boundaries and multiplanar measurements through its high contrast resolution of soft tissues (1, 5). It also provides more accurate measurements than TRUS (4, 15, 16).In order to ensure global standardization in the reporting of prostate MRI findings, PI-RADS v2 published in 2015, which is the revised version of PI-RADS 1.0, and the last updated version PI-RADS v2.1 made available in 2019, propose different calculation methods for the measurement of height in obtaining PV (17, 18). The midaxial plane is recommended for this measurement in PI-RADS v2, while the midsagittal plane is recommended in PI-RADS v2.1. This study aimed to evaluate the interobserver and intraobserver variability of PV calculated by both measurement methods and the agreement between the two measurement methods.  相似文献   
46.
47.
Sarcoidosis is thought to result from the interaction between an unknown environmental antigenic trigger and the host's genetic susceptibility. We hypothesized that sarcoidosis, or one of the disease subsets, could be associated with single nucleotide polymorphisms of C-C chemokine receptor 2 (CCR2) gene. Eight single-nucleotide polymorphisms in CCR2 were studied in a total of 304 Dutch individuals (90 non-L?fgren sarcoidosis, 47 L?fgren's syndrome, 167 control subjects). From the investigated CCR2 polymorphisms, nine haplotypes were deduced (haplotypes 1-9). In patients with L?fgren's syndrome, a strongly significant increase in the frequency of CCR2-haplotype 2, which includes four unique alleles (A at nucleotide position -6752, A at 3,000, T at 3,547, and T at 4,385), was observed compared with control subjects (74% vs. 38% respectively, p < 0.0001), whereas no difference was found between non-L?fgren sarcoidosis and control subjects (both 38%). The association between CCR2-haplotype 2 carriage frequency and L?fgren's syndrome (odds ratio, 4.4; p < 0.0001) remained significant after adjustment for human leukocyte antigen haplotype DRB1*0301-DQB1*0201 (odds ratio, 11.5; p < 0.0001) and female sex (odds ratio, 3.2; p = 0.003), two known risk factors for L?fgren's syndrome. In conclusion, this report describes a strong association between CCR2-haplotype 2 and L?fgren's syndrome. Further studies are needed to understand the molecular mechanisms underlying this association.  相似文献   
48.
Unilateral congenital agenesis of the internal carotid artery (ICA) is a very rare vascular anomaly. Rarely, congenital Horners syndrome has been associated with agenesis of the ICA. This article describes a rare case of congenital Horners syndrome in a patient with ICA agenesis and very unusual aortic arch anomaly. This study was done at Zonguldak Karaelmas University, Faculty of Medicine, No financial support was required for this study.  相似文献   
49.
The fact thatH. pylori gastritis results in an increased secretion of basal and meal-stimulated gastrin, which is also a physiologic amplifier of insulin release directed us to investigate whetherH. pylori gastritis may lead to an enhancement of nutrient-stimulated insulin secretion. For this purpose, we have investigated the insulin responses to both oral glucose and a mixed meal in 15 patients withH. pylori gastritis before and one month after the eradication therapy and also in 15H. pylori-negative control subjects. The areas under the curve (AUC) for serum insulin following both oral glucose and a mixed meal in the patients withH. pylori gastritis before the eradication were significantly (P<0.05) higher than those in theH. pylori-negative controls. After the eradication ofH. pylori, the AUC for serum insulin following oral glucose and mixed meal decreased by 9.4% and 13.1%, respectively (P<0.001 in both), and serum basal and meal-stimulated gastrin levels decreased significantly (P<0.001). These results suggest thatH. pylori gastritis enhances glucose and meal-stimulated insulin release probably by increasing gastrin secretion.Presented in part as an abstract at the 8th Balkan Congress of Endocrinology, Bursa, Turkey, May 3–5, 1995.  相似文献   
50.
Neurenteric cyst is a very rare developmental anomaly. Prenatal diagnosis of mediastinal neurenteric cysts has been reported rarely. We present a case of neurenteric cyst associated with vertebral anomalies diagnosed by prenatal ultrasonography at 31 weeks of gestation, which was treated successfully in the early neonatal period. In addition, we searched the English literature for all cases of mediastinal neurenteric cyst diagnosed in the prenatal period reported to date. We found that only 17 cases were reported previously. We reviewed the reports of these 17 patients along with our case, and we investigated the prenatal and postnatal diagnosis and treatment approaches and the factors influencing the prognosis. Fetuses with mediastinal neurenteric cysts should be monitored regularly by ultrasonography. Fetuses with no signs of hydrops are more likely to survive with proper neonatal center transfer, regular follow-up, and appropriate postnatal approach. Fetuses with hydrops findings have a high risk of fetal and neonatal death.  相似文献   
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