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81.
Objective.?To test the agreement between observers and reproducibility of a technique to display standard cardiac views of the left and right ventricular outflow tracts from four-dimensional volume datasets acquired with Spatiotemporal Image Correlation (STIC).

Methods.?A technique was developed to obtain dynamic multiplanar images of the left ventricular outflow tract (LVOT) and right ventricular outflow tract (RVOT) from volume datasets acquired with STIC. Volume datasets were acquired from fetuses with normal cardiac anatomy. Twenty volume datasets of satisfactory quality were pre-selected by one investigator. The data was randomly assigned for a blinded review by two independent observers with previous experience in fetal echocardiography. Only one volume dataset was used for each fetus. After a training session, the observers obtained standardized cardiac views of the LVOT and RVOT, which were scored on a scale of 1 to 5, based on diagnostic value and image quality (1?=?unacceptable, 2?=?marginal, 3?=?acceptable, 4?=?good, and 5?=?excellent). Median scores and interquartile range, as well as inter- and intraobserver agreement were calculated for each view.

Results.?The mean menstrual age at the time of volume acquisition was 25.5?±?4.5 weeks. Median scores (interquartile range) for LVOT images, obtained by the first and second observers, were 3.5 (2.25–5.00) and 4 (3.00–5.00), respectively. The median scores (interquartile range) for RVOT images obtained by the first and second observers were 3 (3.00–5.00) and 3 (2.00–4.00), respectively. The interobserver intraclass correlation coefficient for the LVOT was 0.693 (95% CI 0.380–0.822), and 0.696 (95% CI 0.382–0.866) for the RVOT. For the intraobserver agreement analysis, observer 1 gave higher scores to the LVOT the second time the volumes were analyzed [LVOT: 3.50 (2.25–5.00) vs. 5.00 (4.00–5.00, p?=?0.008)].

Conclusion.?STIC can be reproducibly used to evaluate fetal cardiac outflow tracts by independent examiners. Slightly better image quality rating scores during the intraobserver variability trial suggests the presence of a learning curve for the manipulation and analysis of volume data obtained by STIC.  相似文献   
82.
Objectives. The soluble form of vascular endothelial growth factor receptor-1 (sVEGFR-1), an antagonist to vascular endothelial growth factor and placental growth factor, has been implicated in the pathophysiology of preeclampsia. Preeclampsia and pregnancy complicated with small for gestational age (SGA) fetuses share some pathophysiologic derangements, such as failure of physiologic transformation of the spiral arteries, endothelial cell dysfunction, and leukocyte activation. The objectives of this study were to: (1) determine whether plasma concentrations of sVEGFR-1 in mothers with SGA fetuses without preeclampsia at the time of diagnosis are different from those in patients with preeclampsia or normal pregnant women, and (2) examine the relationship between plasma concentrations of sVEGFR-1 and Doppler velocimetry in uterine and umbilical arteries in patients with preeclampsia and those with SGA.

Study design. A cross-sectional study was conducted to determine the concentrations of the soluble form of VEGFR-1 in plasma obtained from normal pregnant women (n = 135), women with SGA fetuses (n = 53), and patients with preeclampsia (n = 112). Patients with SGA fetuses and those with preeclampsia were sub-classified according to the results of uterine and umbilical artery Doppler velocimetry examinations. Plasma concentrations of sVEGFR-1 were determined by an ELISA. Since these concentrations change with gestational age, differences among various subgroups were statistically estimated with the delta value, defined as the difference between the observed and expected plasma sVEGFR-1 concentration. The expected values were derived from regression analysis of plasma sVEGFR-1 concentrations in normal pregnancy. Regression analysis and univariate and multivariate analysis were employed.

Results. (1) Mothers with SGA fetuses had a mean plasma concentration of sVEGFR-1 higher than normal pregnant women (p < 0.001), but lower than patients with preeclampsia (p < 0.001). (2) Among patients with SGA fetuses, only those with abnormal uterine artery Doppler velocimetry had a mean plasma sVEGFR-1 concentration significantly higher than normal pregnant women (p < 0.001). (3) Among mothers with SGA fetuses in whom Doppler velocimetry was performed (n = 41), those with abnormalities in both the uterine and umbilical artery velocimetry had the highest mean delta of sVEGFR-1 plasma concentration (mean ± standard deviation (SD): 0.69 ± 0.29). Conversely, patients who had normal Doppler velocimetry in both uterine and umbilical arteries had the lowest mean delta (mean ± SD: 0.09 ± 0.29) of sVEGFR-1 plasma concentrations (ANOVA; p < 0.001). (4) Among patients with preeclampsia in whom Doppler velocimetry was performed (n = 69), those with abnormalities in both the uterine and umbilical artery velocimetry had the highest mean delta sVEGFR-1 plasma concentration (mean ± SD: 1.01 ± 0.22) among all groups classified (ANOVA; p < 0.001). (5) Among patients with SGA and those with preeclampsia, there was a relationship (Chi-square for trend p < 0.001 for both) between the severity of Doppler velocimetry abnormalities and the proportion of patients who had high delta sVEGFR-1 plasma concentrations (defined as a concentration two standard deviations (2SD) above the mean delta of normal pregnant women). (6) Multiple regression analysis suggested that the diagnostic category (e.g., SGA or preeclampsia), Doppler abnormalities, and gestational age at blood sampling were associated with an increase in plasma sVEGFR-1 concentrations (p < 0.001).

Conclusions. These observations provide support for the participation of the soluble receptor of vascular endothelial growth factor in the pathophysiology of SGA with abnormal uterine artery Doppler velocimetry and preeclampsia. An excess of sVEGFR-1 is released into the maternal circulation of patients with preeclampsia and those with SGA fetuses, as abnormalities of impedance to blood flow involve uterine and umbilical circulation.  相似文献   
83.
Objective. Caspase-1 is a component of the NALP3 inflammasome, a cytosolic multiprotein complex that mediates the processing of pro-inflammatory caspases and cytokines. The inflammasome represents the first line of defense against cellular stress and is a crucial component of innate immunity. Caspase-1 is the enzyme responsible for the cleavage and activation of interleukin (IL)-1β, which is a potent pro-inflammatory cytokine, and plays a central role in the mechanisms leading to labor (preterm and term) particularly in the context of intrauterine infection/inflammation. In addition, caspase-1 cleaves IL-18 and IL-33. The objectives of this study were to determine whether there is a relationship between amniotic fluid concentrations of caspase-1 and gestational age, parturition (term and preterm), and intra-amniotic infection/inflammation (IAI).

Study design. A cross-sectional study was conducted including 143 pregnant women in the following groups: (1) mid-trimester of pregnancy (n = 18); (2) term not in labor (n = 25); (3) term in labor (n = 28); (4) preterm labor (PTL) who delivered at term (n = 23); (5) PTL without IAI who delivered preterm (n = 32); (6) PTL with IAI who delivered preterm neonates (n = 17). Caspase-1 concentrations in amniotic fluid were determined by a specific and sensitive immunoassay. Non-parametric statistics were used for analysis.

Results. (1) Caspase-1 was detected in amniotic fluid of women at term, but in none of the mid-trimester samples. (2) Patients in labor at term had a significantly higher median amniotic fluid concentration of caspase-1 than women at term not in labor (term in labor: 10.5 pg/mL, range 0.0–666.0 vs. term not in labor: 5.99 pg/mL, range 0.0–237.4; p < 0.05). (3) Among patients with spontaneous PTL, those with IAI (median 41.4 pg/mL, range 0.0–515.0) had a significantly higher median amniotic fluid caspase-1 concentration than those without IAI who delivered preterm (median 0.0 pg/mL, range 0.0–78.4) and than those who delivered at term (median 0.0 pg/mL, range 0.0–199.5); p < 0.001 for both comparisons.

Conclusions. (1) The presence and concentration of caspase-1 in the amniotic fluid varies as a function of gestational age. (2) Women with spontaneous labor at term had a higher median caspase-1 amniotic fluid concentration than women at term without labor. This suggests that the inflammasome may be activated in spontaneous parturition at term. Since most women with labor do not have intra-amniotic infection, we propose that cellular stress during labor accounts for activation of the inflammasome. (3) Preterm labor associated with infection/inflammation was also associated with a high concentration of caspase-1, suggesting that infection may induce caspase-1 production and activation of the inflammasome. (4) The sequential activation of the inflammasome and caspase-1, leading to interleukin-1β processing and secretion, is a candidate pathway leading to the activation of the common pathway of parturition.  相似文献   
84.
We describe an unusual case of hyperacute hepatic failure following general anesthesia in a patient receiving a simultaneous kidney‐pancreas transplant. Despite an aggressive evaluation of structural, immunological, viral, and toxicological causes, a definitive cause could not be elucidated. The patient required a liver transplant and suffered a protracted hospital course. We discuss the potential causes of fulminant hepatic failure and the perioperative anesthesia management of her subsequent liver transplantation.  相似文献   
85.
OBJECTIVE: The understanding of pathophysiology and cellular mechanisms of chronic heart failure requires the creation of appropriate and accurately characterized animal models, thus enabling meaningful evaluation of evolving medical and surgical therapies. METHODS: The left anterior descending and its diagonal branch were ligated in 12 sheep to induce left ventricular dysfunction. RESULTS: Study of left ventricular pressure-volume loops 3 months post-operatively showed a significant deterioration of both systolic and diastolic indexes of left ventricular function. The left ventricular end-diastolic pressure increased from 3+/-1 to 7+/-1 mmHg (P<0.001) along with a substantial increase in end-diastolic volume from 78+/-8 to 121+/-6 ml (P=0.002) and a significant decrease in cardiac output from 2+/-0.2 to 1.5+/-0.2 l/min (P=0.001). The left ventricular end-systolic pressure-volume relationship deteriorated from 2.7+/-0.37 to 0.7+/-0.16 mmHg/ml (P=0.0002) along with a significant reduction in the pre-load recruitable stroke work (P=0.001). The ejection fraction decreased from 34+/-2% to 16+/-4% (P<0.001) with a significant decrease in +dp/dt and -dp/dt (P=0.009). The mean systemic blood pressure, however, was maintained due to a substantial increase in the systemic vascular resistance (P=0.007). CONCLUSION: This study describes a reproducible large animal model of left ventricular dysfunction. This model is potentially useful to study the pathogenesis of remodelling, surgical management of heart failure and development of novel treatment strategies.  相似文献   
86.
A procedure to optimize the geometrical model of an n-type detector is described. Sixteen lines from seven point sources (241Am, 133Ba, 22Na, 60Co, 57Co, 137Cs and 152Eu) placed at three different source-to-detector distances (10, 20 and 30 cm) were used to calibrate a low-background gamma spectrometer between 26 and 1408 keV. Direct Monte Carlo techniques using the MCNPX 2.6 and GEANT 4 9.2 codes, and a semi-empirical procedure were performed to obtain theoretical efficiency curves. Since discrepancies were found between experimental and calculated data using the manufacturer parameters of the detector, a detail study of the crystal dimensions and the geometrical configuration is carried out. The relative deviation with experimental data decreases from a mean value of 18–4%, after the parameters were optimized.  相似文献   
87.
88.
The Positive and Negative Syndrome Scale (PANSS) is the most widely used instrument to assess the severity of symptoms of schizophrenia. Most studies have showed that PANSS measures five dimensions of symptomatology of schizophrenia. However, few studies have ever investigated the structure of PANSS in Chinese schizophrenia population. We recruited two large independent study samples including 903 and 942 Chinese schizophrenia patients and examined the underlying structure of PANSS. By building a confirmatory factor analysis (CFA) model based on the factor loadings of the exploratory factor analysis (EFA) and by testing the CFA model in an independent validation sample, we found that PANSS scores consisted of five factors, which were positive factor, negative factor, excitement factor, depression factor, and cognitive factor. The items loaded on these factors were similar to the consensus items published in previous studies except for PANSS items P2 conceptual disorganization, P5 grandiosity, N5 abstract thinking, and G11 poor attention. This difference might be due to the influence of culture on clinical presentation of schizophrenia. By elucidating the structure, symptoms of Chinese schizophrenia patients could possibly be deconstructed and investigated in future studies.  相似文献   
89.
Passenger leukocytes have been suggested to be both pro-tolerant and immunogenic. The opportunity to evaluate the role of allogeneic passenger leukocytes in humans was presented by a 47-year-old man who donated bone marrow to his HLA-identical leukemic sister. Eleven years later he developed renal failure. The sister's marrow was noted to be 100% XY karyotype and free of malignancy. She donated a kidney to her brother. Immunosuppression was tapered following transplantation. After 6 months, the recipient was on monotherapy sirolimus, 1 mg every third day. A surveillance biopsy was normal and sirolimus was stopped. Eight weeks later, he presented with severe rejection that reversed with Thymoglobulin. Renal function returned to baseline and has been stable on conventional immunosuppression.  相似文献   
90.
BACKGROUND: We report our preliminary experience in urgent laparoscopically assisted right hemicolectomy for obstructing right-sided colon carcinoma. MATERIALS AND METHODS: From January to April 2005, seven consecutive patients with obstructing right-sided colon carcinoma underwent emergency laparoscopically assisted right or extended right hemicolectomy. Patient demographic data, operative details, and short-term clinical outcomes were prospectively collected and analyzed. RESULTS: The median duration of obstructing symptoms prior to admission was 3 days (range, 1-6 days). Two patients underwent palliative resection and five patients underwent curative resection. The median operative time was 180 minutes (range, 125-350 minutes). There were no conversions to the open procedure. Median blood loss was 30 mL (range, negligible-300 mL). The median times to resuming diet, first bowel motion, and full ambulation were 4 days (range, 3-10 days), 5 days (range, 3-7 days), and 4 days (range, 4-5 days), respectively. The median duration of hospital stay was 7 days (range, 6-19 days). One patient with ischemic heart disease developed acute coronary syndrome postoperatively and died on postoperative day 19. The remaining patients had no complications. The median tumor length was 3.5 cm (range, 2-5 cm) and the median number of lymph nodes removed was 17 (range, 16-36). CONCLUSION: Emergency laparoscopically assisted right hemicolectomy for obstructing right-sided colon carcinoma is feasible and safe, with favorable short-term clinical outcomes and an acceptable number of lymph nodes removed.  相似文献   
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