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31.
More than 14,000 people die from invasive transitional cell carcinoma (TCC) of the urinary bladder yearly in the United States. Cyclooxygenase (COX)-inhibiting drugs are emerging as potential antitumor agents in TCC. The optimal in vitro or in vivo systems to investigate COX inhibitor antitumor effects have not been defined. The purpose of this study was to determine COX-1 and COX-2 expression and antitumor effects of COX inhibitors in human TCC cell lines (HT1376, RT4, and UMUC3 cells) and xenografts derived from those cell lines. COX-2 expression (Western blot, immunocytochemistry) was high in HT1376, modest in RT4, and absent in UMUC3 cells in vitro. Similarly, COX-2 expression was noted in RT4 but not UMUC3 xenografts. COX-2 expression in HT1376 xenografts was slightly lower than that observed in vitro. None of four COX inhibitors evaluated (celecoxib, piroxicam, valeryl salicylate, and NS398) reduced TCC growth in standard in vitro proliferation assays at concentrations that could be safely achieved in vivo (< or =5 micromol/L). Higher celecoxib concentrations (> or =50 micromol/L) inhibited proliferation and induced apoptosis in all three cell lines. Celecoxib or piroxicam treatment in athymic mice significantly delayed progression of HT1376 xenografts, which express COX-2, but not UMUC3 xenografts that lack COX-2 expression. In conclusion, standard in vitro assays were not useful in predicting COX inhibitor antitumor effects observed in vivo. Athymic mice bearing TCC xenografts provide a useful in vivo system for COX inhibitor studies. Results of this study provide justification for further evaluation of COX inhibitors as antitumor agents against TCC.  相似文献   
32.
应用聚合酶链反应(PCR)结合HpaⅡ限制性内切酶消化法(HpaⅡ-PCR)检测58例急性白血病(AL)患儿降钙素(CT)基因的甲基化状态。病例组待检细胞DNA经HpaⅡ消化后,再用两对CT基因特异性引物作PCR扩增,分别产生长度为566bp和1.4kb特异片段。急性淋巴细胞白血病阳性率71.4%(25/35),急性非淋巴细胞白血病78.2%(18/23)。敏感性达10-3。证明CT基因5′高度甲基化是白血病细胞克隆的特异标志。本课题受卫生部、四川省人民医院出国人员基金资助  相似文献   
33.
34.
Prior research on callous-unemotional (CU) traits supports a deficit in recognizing fear in faces and body postures. Difficulties recognising others’ emotions may impair the typical behavioural inhibition for violent behaviour. However, recent research has begun to examine other distress cues such as pain. The present study examined emotion recognition skills, including pain, of school-excluded boys aged 11–16 years (N = 50). Using dynamic faces and body poses, we examined the relation between emotion recognition and CU traits using the youth psychopathic traits inventory (YPI) and the inventory of CU traits. Violent delinquency was covaried in regression analyses. Although fearful facial and fearful bodily expressions were unrelated to CU traits, recognition of dynamic pain facial expressions was negatively related to CU traits using the YPI. The failure to replicate a fear and sad deficit are discussed in relation to previous research. Also, findings are discussed in support of a general empathy deficit for distress cues which may underlie the problem behaviour of young males with CU traits.  相似文献   
35.
The aim of this study was to evaluate whether contrast enhanced fluid attenuated inversion recovery (CE-FLAIR) imaging can be used to predict the severity of meningitis based on leptomeningeal enhancement (LE) score and cerebrospinal fluid signal intensity (CSF-SI) on CE-FLAIR. We retrospectively analyzed data collected from 43 consecutive patients admitted to our hospital due to meningitis. Clinical factors including initial Glasgow Coma Scale (GCS) score, CSF glucose ratio, log CSF protein, log CSF WBC, and prognosis were evaluated. The LE score was semi-quantitatively scored, and we evaluated CSF-SI ratio at the interpeduncular or quadrigerminal cisterns on CE-FLAIR. We evaluated the differences in clinical variables, LE scores and CSF-SI ratios between the recovery and the complication group. We assessed the correlation between clinical variables, LE scores and CSF-SI ratios. The values of log CSF protein, CSF-SI ratio, and LE score were significantly higher in the complication group (p value <0.05). GCS score and CSF glucose ratio were significantly lower in the complication group (p value <0.01). The LE scores had significant negative correlation with GCS scores and CSF glucose ratios (p value <0.001). The LE score was significantly positively correlated with the value of log CSF protein and CSF-SI ratio (p value <0.01). The CSF-SI ratio was negatively correlated with GCS score and CSF glucose ratio (p value <0.01). The CSF-SI ratio was positively correlated with the value of log CSF protein (p value <0.05). Our results suggest that LE score and CSF-SI ratio are well correlated with clinical prognostic factors. We may predict the clinical severity of meningitis by using LE scores and CSF-SI ration on CE-FLAIR imaging.  相似文献   
36.
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   
37.
Assessment of the value of carcinoembryonic antigen reduction ratio as a prognosis factor in rectal cancer     
Chih-Sheng Huang  Jen-Kou Lin  Ling-Wei Wang  Wen-Yih Liang  Chun-Chi Lin  Yuan-Tzu Lan  Huann-Sheng Wang  Shung-Haur Yang  Jeng-Kai Jiang  Wei-Shone Chen  Tzu-Chen Lin  Shih-Ching Chang 《American journal of surgery》2014

Background

Carcinoembryonic antigen (CEA) is the most widely used tumor marker for colorectal cancer. This study aimed to investigate the role of CEA reduction ratio after preoperative chemoradiotherapy (CRT).

Methods

We enrolled 284 patients who underwent preoperative CRT followed by radical surgical resection. Patients were divided into 3 groups: serum CEA levels before CRT (pre-CRT CEA) less than 5 ng/mL (group 1); pre-CRT CEA of 5 ng/mL or more with CEA reduction ratio of 50% or more (group 2); and pre-CRT CEA of 5 ng/mL or more with CEA reduction ratio less than 50% (group 3).

Results

The 5-year disease-free survival (DFS) rate was not different between groups 1 (71.8%) and 2 (69.4%) but was signi?cantly lower in group 3 (49.5%). CEA group, lymph node status after CRT (ypN) stage, and histologic type were independent prognostic factors for DFS on multivariate analysis.

Conclusions

CEA reduction ratio might be an independent prognostic factor for DFS in rectal cancer patients treated with preoperative CRT and radical surgery.  相似文献   
38.
Predictive utility of cyclo-oxygenase-2 expression by colon and rectal cancer     
Kristel C. Lobo Prabhu  Lan Vu  Simon K. Chan  Terry Phang  Allen Gown  Steven J. Jones  Sam M. Wiseman 《American journal of surgery》2014

Background

Cyclo-oxygenase-2 (COX-2), an inducible enzyme expressed in areas of inflammation, is a target of interest for colorectal cancer therapy. Currently, the predictive significance of COX-2 in colorectal cancer remains unclear.

Methods

Tissue microarrays were constructed using 118 colon cancer and 85 rectal cancer specimens; 44 synchronous metastatic colon cancer and 22 rectal cancer lymph nodes were also evaluated. COX-2 expression was assessed by immunohistochemistry. Univariate analysis was used to determine the predictive significance of clinicopathologic variables. Overall survival, disease-specific survival, and disease-free survival were the main outcomes examined.

Results

COX-2 was found to be expressed in 93% of colon cancers and 87% of rectal cancers. Decreased COX-2 expression was related to decreased disease-specific survival (P = .016) and decreased disease-free survival (P = .019) in the rectal cancer cohort but not in the colon cancer cohort.

Conclusions

COX-2 expression has predictive utility for management of rectal but not colon cancer.  相似文献   
39.
Microwave coagulation therapy and drug injection to treat splenic injury     
Guoming Zhang  MD  Yuanyuan Sun  Nannan Mu  Lanfen LiuPing Liang  MD 《The Journal of surgical research》2014

Background

The present study compares the efficacy of 915- and 2450-MHz contrast-enhanced ultrasound (CEUS)–guided percutaneous microwave coagulation with that of CEUS-guided thrombin injection for the treatment of trauma-induced spleen hemorrhage.

Materials and methods

In a canine splenic artery hemorrhage model with two levels of arterial diameter (A, <1 mm and B, between 1 and 2 mm), hemostatic therapy was performed using 915- and 2450-MHz microwaves and drug injection. Therapy efficacy was measured by comparing bleeding rate, hemostatic time, bleeding index, bleeding volume, and pathology.

Results

The most efficient technique was CEUS-guided 915-MHz percutaneous microwave coagulation therapy in terms of action time and total blood loss. The success rate of the 915-MHz microwave group was higher than that of the 2450-MHz microwave and the drug injection groups (except A level, P < 0.05). Hemostatic time, bleeding index, and bleeding volume were significantly less in the 915-MHz microwave group than those in the 2450-MHz microwave and drug injection groups (P < 0.05). Obvious degeneration and necrosis of parenchyma and large intravascular thrombosis were observed in the cavity of larger vessels in the 915-MHz microwave group, but pathologic changes of light injury could be seen in the other groups.

Conclusions

The present study provides evidence that microwave coagulation therapy is more efficient than thrombin injection for the treatment of splenic hemorrhage. Furthermore, treatment with 915-MHz microwaves stops bleeding more rapidly and generates a wider cauterization zone than does treatment with 2450-MHz microwaves.  相似文献   
40.
手术病人麻醉后恢复的特点   总被引:8,自引:0,他引:8  
张兰霞  吴新民 《中华护理杂志》1998,(11)
分析1995年8月至1996年11月麻醉恢复室接收433例病人的情况,以期了解手术后麻醉恢复期护理的特点。其中男性40.6%,女性59.4%,平均年龄54.1±14.7岁(6~82岁),平均停留时间44min(5~265min),98.8%的病人平稳恢复后送回病房,1.2%的病人转入SICU。实施麻醉方法除6例为连续硬膜外麻醉或腰麻外,余为全麻或强化麻醉。根据Ramsay评分法,入室时95%以上病人5~6分,出室时92%的病人是4分以下,所有病人血压、心率无显著变化,没有给予任何血管活性药物。入室时63.3%的病人自主呼吸已经恢复。由于麻醉药和肌肉松弛药对中枢和呼吸肌的残留抑制作用,术后早期病人最易出现缺氧。因此全麻术后必须认真监测病人呼吸功能恢复情况,提高吸入氧浓度,根据病情需要保留气管导管,或短时间的机械通气,提高吸入氧浓度,以保证病人呼吸道通畅,避免CO2的潴留,特别是缺氧的发生。从观察病例可以看出,全麻术后未能立即清醒,平均约45min后意识方能满意恢复。  相似文献   
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