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61.
The unique ability of olfactory neurons to regenerate in vitro has allowed their use for the study of olfactory function, regeneration, and neurodegenerative disorders; thus, characterization of their properties is important. This present study attempts to establish the timeline of structural (protein expression) and functional (odorant sensitivity) maturation of human olfactory epithelial cells (hOE) in vitro using biopsy‐derived cultured tissue. Cells were grown for 7 days; on each day, cells were tested for odorant sensitivity using calcium imaging techniques and then protein expression of each cell was tested using immunocytochemistry for proteins typically used for characterizing olfactory cells. Previous studies have shown that mature olfactory neurons in vitro attain a unique “phase‐bright” morphology and express the olfactory marker protein (OMP). By day 3 in vitro, a variety of cells were odorant‐sensitive, including both “phase‐bright” and “phase‐dark” cells that have previously been considered glial‐like cells. The functional maturation of these hOEs appears to take place within 4 days. Interestingly, the emergence of an odorant sensitivity profile of both phase‐bright and phase‐dark cells preceded the expression of marker protein expression for OMP (which is expressed only by mature neurons in vivo). This structural maturation took 5 days, suggesting that the development of odorant sensitivity is not coincident with the expression of marker molecules that are hallmarks of structural maturation. These results have important implications for the use of hOEs as in vitro models of olfactory and neuronal function. © 2013 Wiley Periodicals, Inc.  相似文献   
62.
63.
Targeting stathmin in prostate cancer   总被引:4,自引:0,他引:4  
Stathmin is the founding member of a family of microtubule-destabilizing proteins that regulate the dynamics of microtubule polymerization and depolymerization. Stathmin is expressed at high levels in a variety of human cancers and provides an attractive molecule to target in cancer therapies that disrupt the mitotic apparatus. We developed replication-deficient bicistronic adenoviral vectors that coexpress green fluorescent protein and ribozymes that target stathmin mRNA. The therapeutic potential of these recombinant adenoviruses was tested in an experimental androgen-independent LNCaP prostate cancer model. Adenovirus-mediated transfer of anti-stathmin ribozymes resulted in efficient transduction and marked inhibition of stathmin expression in these cells. Cells that were transduced with the anti-stathmin adenoviruses showed a dramatic dose-dependent growth inhibition. This was associated with accumulation of LNCaP cells in the G2-M phases of the cell cycle. A similar dose-dependent inhibition of clonogenic potential was also observed in cells infected with anti-stathmin adenoviruses. Morphologic and biochemical analysis of infected cells showed a marked increase in apoptosis characterized by detachment of the cells, increased chromatin condensation, activation of caspase-3, and fragmentation of internucleosomal DNA. If these findings are confirmed in vivo, it may provide an effective approach for the treatment of prostate cancer.  相似文献   
64.
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66.
The purpose of this study was to estimate the prevalence of mental health problems among a representative sample of homeless women with and without dependent children and determine if the effects of risk factors for mental health are modified by the presence of dependent children. Homeless women (n = 522) were recruited in 2004–2005 from shelters and meal programs in Toronto, Canada. Linear and logistic regression was performed to identify factors associated with mental health status. Poor mental health was associated with low perceived access to social support, physical/sexual assault in the past 12 months, presence of a chronic health condition, and presence of a drug use problem in the past month. Efforts to improve mental health in this population will need to address the associated problems of victimization, substance abuse, and lack of social supports.  相似文献   
67.
ObjectivesTo summarize the current status of clinicopathological and molecular markers for the prediction of recurrence or progression or both in non–muscle-invasive and survival in muscle-invasive urothelial bladder cancer, to address the reproducibility of pathology and molecular markers, and to provide directions toward implementation of molecular markers in future clinical decision making.Methods and materialsImmunohistochemistry, gene signatures, and FGFR3-based molecular grading were used as molecular examples focussing on prognostics and issues related to robustness of pathological and molecular assays.ResultsThe role of molecular markers to predict recurrence is limited, as clinical variables are currently more important. The prediction of progression and survival using molecular markers holds considerable promise. Despite a plethora of prognostic (clinical and molecular) marker studies, reproducibility of pathology and molecular assays has been understudied, and lack of reproducibility is probably the main reason that individual prediction of disease outcome is currently not reliable.ConclusionsMolecular markers are promising to predict progression and survival, but not recurrence. However, none of these are used in the daily clinical routine because of reproducibility issues. Future studies should focus on reproducibility of marker assessment and consistency of study results by incorporating scoring systems to reduce heterogeneity of reporting. This may ultimately lead to incorporation of molecular markers in clinical practice.  相似文献   
68.
Background contextThere is a persistent trend for more outpatient lumbar discectomies in the United States.PurposeTo investigate the characteristics of the patients selected for ambulatory procedures.Study designRetrospective cohort study.Patient sampleForty-seven thousand one hundred twenty-five patients who underwent outpatient and 102,592 patients undergoing inpatient lumbar discectomies and were were registered in the State Ambulatory Surgery Database (SASD) and State Inpatient Database (SID), respectively, for New York, California, Florida, and North Carolina from 2005 to 2008.Outcome measuresRate of outpatient procedures, 30-day readmissions, and hospital charges.MethodsWe performed a retrospective cohort study involving patients who underwent outpatient and inpatient lumbar discectomies and were registered in SASD and SID, respectively, for New York, California, Florida, and North Carolina from 2005 to 2008. Logistic regression models were used to demonstrate the association of socioeconomic factors with the odds of undergoing an outpatient procedure.ResultsMale gender (odds ratio [OR], 1.05; 95% confidence interval [CI], 1.03–1.08), private insurance (OR, 1.93; 95% CI, 1.86–2.01), lower Charlson Comorbidity Index (OR, 4.04; 95% CI, 3.17–5.16), and higher volume hospitals (OR, 1.06; 95% CI, 1.04–1.08) were significantly associated with outpatient procedures. Higher income (OR, 0.83; 95% CI, 0.81–0.85), older age (OR, 0.996; 95% CI, 0.995–0.997), coverage by Medicaid (OR, 0.89; 95% CI, 0.83–0.96), African Americans (OR, 0.65; 95% CI, 0.60–0.70), and other minority races were associated with decreased odds of outpatient procedures. The rate of 30-day postoperative readmissions was higher among inpatients. Institutional charges were significantly lower for outpatient lumbar discectomies. The median charge for inpatient surgery was $24,273 as compared with $11,339 for the outpatient setting (p<.0001).ConclusionsAccess to ambulatory lumbar discectomies appears to be more common for younger, white, male patients, with private insurance and less comorbidities, in the setting of higher volume hospitals. Further investigation is needed in the direction of mapping these disparities for appropriate resource utilization.  相似文献   
69.
GFR decline in patients with CKD has been widely approximated using linear models, but this linearity assumption is not well validated. We conducted a matched case-control study in children from the Chronic Kidney Disease in Children (CKiD) cohort ages 1–16 years with mild to moderate CKD to assess whether GFR decline follows a nonlinear trajectory as CKD approaches ESRD. Children (n=125) who initiated RRT (cases) during follow-up were individually matched by CKD stage at baseline and glomerular/nonglomerular diagnosis with children (n=125) who remained RRT-free when the corresponding case initiated RRT (controls). GFR trajectories were compared using log-linear and piecewise log-linear mixed effects models adjusted for baseline characteristics. From study entry to 18 months before RRT, GFR declined 7% faster among cases compared with controls. However, GFR declined 26% faster among cases compared with controls (P<0.001) during the 18 months before RRT. Nonlinearity in the rate of kidney function loss, which was shown in this cohort, may preclude accurate clinical prediction of the timing of RRT and adequate patient preparation. This study should prompt the characterization of predictive factors that may contribute to an acceleration of kidney function decline.GFR is a key measurement of kidney function, and the degree of GFR decline over time is a reflection of the severity of CKD progression. GFR decline has been approximated as linear or log-linear in most analyses of progression, an assumption that has been consistent with available data.14 However, many studies rely on relatively short follow-up periods and few repeated measures. Given the convenience of assuming a linear GFR trajectory, which results from the ease of modeling and interpreting linear slopes, few studies have sought to validate the linearity assumption and explore the possibility of nonlinear GFR decline. However, nonlinearity in GFR decline has been observed in some epidemiologic studies,57 and the implications on the risk for adverse outcomes have generated interest.8 A CKD cohort study in France found that about one half of its patients experienced nonlinear GFR decline during the last year before dialysis.5 A study by Li et al.9 used a flexible approach to model nonlinearity in GFR trajectories. Li et al.9 found evidence of nonlinear GFR trajectory behavior in adult patients with CKD, and furthermore, the probability of having nonlinear features in an individual trajectory was associated with known risk factors for CKD progression. O’Hare et al.10 found several distinct nonlinear patterns of GFR decline in the 2 years before dialysis initiation in Veterans Affairs patients.Clinical strategies and subsequent patient response to care could potentially benefit from new insights into the variable paths of progression in patients with CKD.10,11 The question of whether characterizing the nonlinearity in the GFR trajectory can assist the identification of risk groups for outcomes, such as ESRD, remains unexplored. The implications on future outcomes of an increased rate of GFR decline could inform clinical decisions about screening frequencies, treatment, or preparation for RRT.The Chronic Kidney Disease in Children (CKiD) study is an ongoing cohort study of children with CKD who, at baseline, had an eGFR between 30 and 90 ml/min per 1.73 m3 and were ages 1–16 years. An end point of the study is RRT defined as transplant or dialysis. To determine whether trajectories of GFR accelerate before RRT, we nested a case-control study, in which cases were children observed to have received RRT and controls were children with CKD who remained RRT-free at the time when the corresponding case initiated RRT.There were 147 children who experienced RRT during follow-up. Each case was matched individually to an eligible control at the time of the case occurrence. The matching factors included baseline CKD stage, glomerular/nonglomerular diagnosis, and, through design, the amount of follow-up time from study entry. Matching was done without replacement, and 22 cases were excluded from the analyses, because no appropriate control was available. We used a random sequence to determine the order of matching. The analysis was, thus, based on 125 matched case-control pairs. Demographic and clinical characteristics of cases and controls at baseline are shown in
CharacteristicsCases (n=125)Controls (n=125)
Age, yr12.64 (9.23–14.53)12.33 (8.71–14.74)
Sex (girls), N (%)38 (30.4)57 (45.6)
Race (nonwhite), N (%)51 (40.8)36 (28.8)
Urine protein/creatinine ratio1.74 (0.48–4.04)0.60 (0.26–1.76)
Proteinuria, N (%)
 0.2≤protein/creatinine ratio<256 (46.7)71 (59.7)
 Protein/creatinine ratio≥251 (42.5)23 (19.3)
Baseline GFRa32.21 (26.43–39.64)35.77 (27.86–43.78)
Glomerular diagnosis, N (%)a47 (37.6)47 (37.6)
Open in a separate windowMedian (interquartile range) unless otherwise indicated.aBaseline GFR and glomerular/nonglomerular diagnosis were matching factors.We compared the GFR trajectories using log-linear and piecewise log-linear mixed effects models, with the piecewise model specified to allow a change of the GFR slope at 18 months before RRT. Models were adjusted for baseline characteristics, including age, race, sex, and proteinuria status. and33 show the adjusted results from the mixed effects model analyses. The Akaike Information Criterion indicated that the piecewise log-linear model (including a spline or changing slope at 18 months before RRT) was a better fit to the data than the log-linear model that assumed a single slope across the entire period of observation. The GFR of cases declined at an adjusted rate of 6.8% per year (P <0.001) during the time before the spline in the earlier period of observation and 32.4% per year (P <0.001) after the spline within 18 months of RRT. The GFR of controls did not change significantly (P=1.00) before the spline and declined at an adjusted rate of 9.0% (P <0.001) after the spline. Although the rates of GFR decline comparing cases with controls differed by only 7% before the spline, the GFR of cases declined 26% faster (P <0.001) compared with controls within 18 months of RRT, suggesting an acceleration in the GFR decline during this period in the case group. This acceleration, which was quantified by the piecewise log-linear mixed effects model, could be clearly seen from the data and nonparametric smooth fits (Figure 1). The variability around the piecewise log-linear fit was assessed by the root mean square error (RMSE) and found to be similar between cases and controls (RMSE for controls=0.303; RMSE for cases=0.303), indicating an equally good fit. When a single slope was fit to the data, the GFR decline rate for cases was overestimated before the spline and considerably underestimated within 18 months of RRT. To assess whether the acceleration in decline was a function of the log scale, models were rerun with GFR in the natural scale. The results showed similar nonlinear patterns but a poorer model fit to the data.

Table 2.

The adjusted expected percent GFR change rates in the log-linear mixed effects model
Case GroupAdjusted % GFR Change per YearSEM (%)P Value
Controls−3.21.20.01
Cases−18.20.9<0.001
Cases-controls−15.51.3<0.001
AIC260.78
Open in a separate windowParameter estimates from the models are provided in Supplemental Appendix II. All results were adjusted for baseline characteristics, including age, race, sex, and proteinuria status. AIC, Akaike Information Criterion.

Table 3.

The adjusted expected percent GFR change rates in the piecewise log-linear mixed effects model
Case GroupBefore 18 mo before RRT of CasesAfter 18 mo before RRT of CasesDifference between Early and Late Slopesa
Adjusted % GFR Change per YearSEM (%)P ValueAdjusted % GFR Change per YearSEM (%)P ValueAdjusted % GFR Change per YearSEM (%)P Value
Controls0.31.50.87−9.02.5<0.0019.23.30.01
Cases−6.81.3<0.001−32.41.3<0.00127.42.0<0.001
Cases-controls−7.01.9<0.001−25.72.5<0.001
AIC149.14
Open in a separate windowParameter estimates from the models are provided in Supplemental Appendix II. All results were adjusted for baseline characteristics, including age, race, sex, and proteinuria status.aDifference resulting from the piecewise linear mixed effects model estimated in the log scale and then exponentiated.Open in a separate windowFigure 1.Nonlinear GFR decline before RRT can be approximated with a piece-wise log-linear model. A and B show the smooth fit of log GFR over time for cases of RRT and matched controls anchoring at the RRT onset time of cases. C and D show the fit from the adjusted log-linear and adjusted piecewise log-linear mixed effects models for cases of RRT and matched controls anchoring at the RRT onset time of cases. Models were adjusted for baseline characteristics including age, race, sex, and proteinuria status.Our results show that, although linear or log-linear GFR decline is a convenient assumption for longitudinal studies of CKD progression, individuals experience periods of accelerated decline. Li et al.9 showed that patients in the African American Study of Kidney Disease and Hypertension experienced a variety of nonlinear progression patterns. O’Hare et al.10 classified CKD patients who progressed to dialysis into four GFR trajectory categories and found evidence that patients with mild to moderate CKD experienced more rapid renal function deterioration in the 2 years before reaching long-term dialysis. In the current study assessing progression in children with CKD, we found similar results, indicating that RRT events are preceded by a period of accelerated decline in GFR. It is likely that this period of precipitous loss in kidney function is a key factor in the determination of the timing of RRT. An acceleration of GFR decline may be a primary feature of a worsening clinical profile that prompts a clinician to initiate dialysis or transplant. The question arises as to what contributes to accelerated kidney function loss. A primary epidemiologic challenge is to find predictors that antecede the acceleration and are amenable to intervention to prevent or delay such accelerated loss and RRT. Clearly, these results and the questions that they raise speak to a need for additional investigations of CKD progression in various populations, with care taken to appropriately characterize changing levels of factors that are known predictors of CKD progression. The timing of potential insults to the kidney (e.g., loss of control of BP) may hold important information concerning the patterns of CKD progression and nonprogression. O’Hare et al.10 found that rates of recommended pre-ESRD care were lower for those patients experiencing the most rapid progression before dialysis initiation. Ambrogi et al.5 suggested that nonlinear patterns in GFR decline might create difficulty in estimating the timing of dialysis.These results may also highlight the coarseness of current methods for assessing the impact of risk factors on CKD progression, which mainly rely on the assumption of linear decline in kidney function. Analyses assuming linear decline average over nonlinear patterns that speak to the true nature of the exposure–outcome relationships. More sensitive analyses may be needed to characterize the heterogeneity in the patterns that describe CKD progression and assess the impact of often changing values of the exposure. Improvements in how we characterize patterns of progression could lead to new approaches to clinical care, because accelerations in kidney function loss may complicate the timing of RRT and pre-ESRD care.7,10There are several strengths of this study. We drew from a well characterized cohort of children with CKD with directly measured GFR at the first two annual study visits and all even visits thereafter. The CKiD study also has an internally derived estimating equation for GFR to capture kidney function in odd visit years of the study, thereby providing regular GFR assessments for characterizing nonlinear patterns of GFR decline. The CKiD study has longitudinal data for up to 6 years of follow-up, and the multicenter setting with 43 clinical sites provides a sample of children highly representative of the pediatric CKD population in care in the United States. By adopting the case-control design, we were able to compare the nonlinearity of the GFR trajectory before RRT with the expected trajectory in comparable children who had not yet experienced RRT.There are also notable limitations to the current analysis. There were only 125 case-control pairs, and our GFR assessments were annual, limiting the degree to which heterogeneity in progression to RRT could be assessed among the case group. As has been reported previously, there is likely variation in GFR patterns before RRT.10 However, what is clear from the current study is that, on average, children approaching RRT experience acceleration in their loss of kidney function. Another consideration is the assumption of a break in linearity at 18 months before RRT, which provided sufficient data before and after the spline for our analyses but is an oversimplification of what is likely a more prolonged period of acceleration in GFR decline. However, our choice of 18 months before RRT to examine changes in the rate of GFR decline is consistent with other studies that have noted similar rapid declines in kidney function within 2 years of dialysis.10,12 Finally, it should be noted that, although cases and controls were matched, the models in and33 did not cluster on the matched pairs. Our final model provided practically identical results to a model including an additional random effect for case-control pair, and it had modestly higher precision.  相似文献   
70.
Digital imaging analysis to assess scar phenotype     
Brian J. Smith BSc  Nichole Nidey BA  Steven F. Miller PhD  Lina M. Moreno Uribe DDS  PhD  Christian L. Baum MD  Grant S. Hamilton III MD  George L. Wehby PhD  Martine Dunnwald PharmD  PhD 《Wound repair and regeneration》2014,22(2):228-238
In order to understand the link between the genetic background of patients and wound clinical outcomes, it is critical to have a reliable method to assess the phenotypic characteristics of healed wounds. In this study, we present a novel imaging method that provides reproducible, sensitive, and unbiased assessments of postsurgical scarring. We used this approach to investigate the possibility that genetic variants in orofacial clefting genes are associated with suboptimal healing. Red‐green‐blue digital images of postsurgical scars of 68 patients, following unilateral cleft lip repair, were captured using the 3dMD imaging system. Morphometric and colorimetric data of repaired regions of the philtrum and upper lip were acquired using ImageJ software, and the unaffected contralateral regions were used as patient‐specific controls. Repeatability of the method was high with intraclass correlation coefficient score > 0.8. This method detected a very significant difference in all three colors, and for all patients, between the scarred and the contralateral unaffected philtrum (p ranging from 1.20?05 to 1.95?14). Physicians’ clinical outcome ratings from the same images showed high interobserver variability (overall Pearson coefficient = 0.49) as well as low correlation with digital image analysis results. Finally, we identified genetic variants in TGFB3 and ARHGAP29 associated with suboptimal healing outcome.  相似文献   
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