首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2768篇
  免费   135篇
  国内免费   29篇
耳鼻咽喉   14篇
儿科学   29篇
妇产科学   17篇
基础医学   439篇
口腔科学   45篇
临床医学   258篇
内科学   474篇
皮肤病学   32篇
神经病学   175篇
特种医学   290篇
外科学   483篇
综合类   24篇
预防医学   111篇
眼科学   29篇
药学   265篇
中国医学   29篇
肿瘤学   218篇
  2023年   22篇
  2022年   62篇
  2021年   89篇
  2020年   30篇
  2019年   60篇
  2018年   82篇
  2017年   54篇
  2016年   83篇
  2015年   128篇
  2014年   159篇
  2013年   160篇
  2012年   247篇
  2011年   228篇
  2010年   133篇
  2009年   114篇
  2008年   173篇
  2007年   145篇
  2006年   140篇
  2005年   125篇
  2004年   98篇
  2003年   81篇
  2002年   57篇
  2001年   42篇
  2000年   52篇
  1999年   42篇
  1998年   25篇
  1997年   24篇
  1996年   34篇
  1995年   19篇
  1994年   14篇
  1993年   5篇
  1992年   8篇
  1991年   16篇
  1990年   12篇
  1989年   12篇
  1988年   11篇
  1987年   19篇
  1986年   13篇
  1985年   16篇
  1984年   8篇
  1983年   8篇
  1982年   5篇
  1981年   8篇
  1980年   12篇
  1979年   12篇
  1978年   7篇
  1977年   7篇
  1976年   6篇
  1973年   3篇
  1967年   3篇
排序方式: 共有2932条查询结果,搜索用时 15 毫秒
31.
This study investigated wound contraction rates according to anatomical regions and wound morphology according to skin tension line in a micropig porcine model. Of the four animals used, skin tension morphology was determined in one pig. In the remaining three pigs, six pairs of full‐thickness skin excisions were created on the dorsum (six square and six circular). The wounds were grouped, Wounds #1 through #5, according to the skin tension line and anatomical regions: Wounds #1 and #2, cephalic; Wounds #4 and #5, caudal; and Wound #3, center. Wound sizes and contraction rates were calculated for 28 days. A static tension topography of the micropig dorsum was obtained. Excisional wounds deformed along the local tension vector and healed in this fashion. Wound contraction rates were significantly higher for cephalic wounds (p = 0.004). No significant difference in wound contraction rates were observed between square and circular wounds. Final wound morphology was related to the local tension vector and initial wound shape. Cephalic wounds contracted more quickly. Further studies are needed to characterize scar formation after primarily closed surgical wounds in relation to the newly established skin tension topography and to elucidate the mechanism behind the variable wound contraction rates in the cephalocaudal gradient.  相似文献   
32.

Purpose

The objective of the study was to validate the previously reported lookup Table and Bladder Cancer Research Consortium (BCRC) nomogram in predicting cancer-specific mortality (CSM) and all-cause mortality (ACM) after radical cystectomy using an external cohort from South Korea.

Methods

The study comprised 409 patients. Discrimination was quantified with the concordance index. The relationship between the model-derived and actual CSM and ACM was graphically explored within calibration plots. Clinical net benefit was evaluated by decision curve analysis.

Results

Of the 409 patients, 147 (35.9 %) had died from various causes. One hundred two deaths were attributable to bladder cancer. For CSM at 5 years, the bootstrap-corrected concordance indices of the American Joint Committee on Cancer (AJCC) staging system, lookup Table, and BCRC nomogram were 71.8 % (95 % confidence interval [CI] 66.9–76.5), 73.0 % (95 % CI 67.9–78.0), and 76.2 % (95 % CI 71.6–80.9), respectively. For ACM at the same time point, the discrimination accuracies of these models were 70.7 % (95 % CI 66.7–74.6), 72.8 % (95 % CI 68.5–76.9), and 76.2 % (95 % CI 72.3–80.2), respectively. The calibration plots tended to exaggerate both survival outcomes in all models. When compared to the lookup Table as well as the AJCC staging system, the BCRC nomogram performed well across a wide range of threshold probabilities using decision curve analysis.

Conclusions

The BCRC nomogram was characterized by higher accuracy and larger potential clinical benefit compared to the lookup Table. However, there is a great need for additional models that consider outcomes of patients for whom the existing models do not apply.  相似文献   
33.
34.
35.
ObjectiveThe efficacy and safety of manual aspiration thrombectomy using Penumbra in an acute occlusion of large intracranial arteries has been proven in many previous studies. Our study aimed to retrospectively assess the efficacy and safety of manual aspiration thrombectomy using Penumbra in patients with small vessel occlusions (M2 segment of the MCA).MethodsWe conducted a retrospective review of 32 patients who underwent manual aspiration thrombectomy using the Penumbra 4 MAX Reperfusion Catheter for treatment of an M2 occlusion between January 2013 and November 2014. We evaluated immediate angiographic results and clinical outcomes through review of patient electronic medical records.ResultsThere were slightly more men in this study (M : F=18 : 14) and the median age was 72.5 (age range : 41–90). The rate of successful recanalization (TICI grade ≥2b) was 84% (27/32). NIHSS at discharge and favorable clinical outcomes at 3 months were significantly improved than baseline. Median initial NIHSS score was 10 (range : 4–25) and was 4 (range : 0–14) at discharge. Favorable clinical outcomes (mRS score ≤2 at 3 months) were seen in 25 out of 32 patients (78%). There were no procedure-related symptomatic intracerebral hemorrhages. One patient expired after discharge due to a cardiac problem.ConclusionManual aspiration thrombectomy might be safe and is capable of achieving a high rate of successful recanalization and favorable clinical outcomes in patients with distal cerebral vessel occlusion (M2).  相似文献   
36.
OBJECTIVE: Redistribution hypothermia adversely affects hemodynamics and postoperative recovery in patients undergoing cardiac surgery. In off-pump coronary bypass surgery (OPCAB), maintaining the temperature is important because warming by cardiopulmonary bypass is omitted. Pre-warming studies reported earlier showing pre-warming as an effective means of preventing redistribution hypothermia was time consuming since it required at least 1-2h to pre-warm the patients before the surgery. Because pre-warming for such a long time is impractical in clinical practice, this study evaluated the efficacy of active warming during the preanesthetic period for the prevention of redistribution hypothermia in the early operative period of OPCAB. METHODS: After gaining the approval of Institutional Review Board and informed consent from the patients, 40 patients undergoing OPCAB were divided into control and pre-warming groups. The patients in control group (n=20) were managed with warm mattresses and cotton blankets, whereas patients in pre-warming group (n=20) were actively warmed with a forced-air warming device before the induction of anesthesia. Hemodynamic variables and temperature were recorded before anesthesia (Tpre) and at 30 min intervals after anesthesia for 90 min (T30, T60, and T90). RESULTS: Active warming duration was 49.7+/-9.9 min. There were no statistically significant differences in skin temperature, core temperature and hemodynamic variables between the two groups at preinduction period except for mean arterial pressure and central venous pressure. The core temperature at T30, T60, and T90 was statistically higher in pre-warming group than that in control group. Core temperature of six (30%) and seven patients (35%) in control group was reduced below 35 degrees C at T60 and T90, respectively, whereas core temperature of only one patient (5%) in pre-warming group was reduced below 35 degrees C at T90 (P=0.02). CONCLUSIONS: Active warming using forced air blanket before the induction of anesthesia reduced the incidence and degree of redistribution hypothermia in patients undergoing OPCAB. It is a simple method with reasonable cost, which does not delay the induction of anesthesia nor the surgery.  相似文献   
37.

Objective

Although partial nephrectomy (PN) is the standard treatment for localized clinical T1a renal cell carcinoma (RCC), treatment of larger renal tumors is controversial. We evaluated the oncological outcomes and perioperative complications after radical and PN for RCC ≥4 cm.

Patients and methods

We retrospectively analyzed the data of 2,373 patients surgically treated for nonmetastatic RCC with clinical T1b or T2 (≥4 cm). The propensity scores for surgery type were calculated, and the partial group was matched to the radical group in a 1:3 ratio. The oncological outcomes were compared using Kaplan-Meier analysis and multivariate Cox regression models were used to identify the independent predictors of progression-free, cancer-specific, and overall survival.

Results

All differences in preoperative clinical characteristics disappeared after matching. There were no significant differences in progression-free, cancer-specific, or overall survival between the partial and radical groups in the matched cohort. The patients’ age, tumor size, cellular grade, and pathologic stage were independent predictors for all 3 survival outcomes. However, early complications (<30 d postoperative) were significantly more common in the partial group (P<0.001). In a subgroup analysis of the patients with clinical T2 stage, there were no significant differences in all 3 survival outcomes.

Conclusions

The partial and radical nephrectomy groups had equivalent oncological outcomes. Although the early complication rate was significantly higher after PN, it should be considered as a valuable treatment option even in patients with clinical T1b or higher RCC.  相似文献   
38.

Objectives

To investigate the effect of variant histology (VH) on survival after radical nephroureterectomy in patients with upper urinary tract urothelial carcinoma (UTUC) and the effect of adjuvant chemotherapy on the survival of patients with UTUC with VH.

Materials and methods

A total of 452 patients who underwent radical nephroureterectomy for UTUC without neoadjuvant chemotherapy in our institution between 1991 and 2012 were retrospectively analyzed. We performed a comparative analysis between pure UTUC and UTUC with VH groups. The Kaplan-Meier method was used to calculate survival estimates for cancer-specific survival (CSS) and overall survival (OS), and log-rank test was used to conduct comparisons between the groups. Univariate and multivariate Cox-proportional hazard regression analyses were performed to evaluate significant variables associated with CSS and OS.

Results

UTUC with VH was present in 41 (9.1%) patients. UTUC with VH showed aggressive clinicopathological features in comparison with pure UTUC. The Kaplan-Meier curves showed significantly decreased 5-year CSS and OS (both, P<0.001) in UTUC with VH group. Multivariate analysis revealed that VH was an independent predictor of CSS (P<0.001) and OS (P<0.002). The Kaplan-Meier curves also showed significantly decreased 5-year CSS and OS in UTUC with the VH group compared to the pure UTUC group in patients who received adjuvant chemotherapy.

Conclusions

We found that UTUC with VH harbored aggressive biologic features, and VH was an independent prognostic factor for CSS and OS on both univariate and multivariate analyses. In addition, UTUC with VH group had poorer survival outcomes than pure UTUC group in patients who received adjuvant chemotherapy. Consequently, adjuvant treatment modalities other than adjuvant chemotherapy should be considered in this group.  相似文献   
39.
A 51-year-old man was admitted with microscopic hematuria at 10 years after living donor renal transplantation. In order to distinguish between acute tubular necrosis and acute rejection, a graft biopsy was performed under ultrasound guidance at 1 month posttransplantation. Doppler sonography revealed 3 pulsatile cystic masses and an arteriovenous fistula (AVF) in the lower kidney pole. Selective transplant renal angiography revealed 3 pseudoaneurysms with an AVF supplied by a lobular artery in the lower pole. The diagnosis was AVF with pseudoaneurysm, which developed secondary to percutaneous renal allograft biopsy. Interventional treatment was performed because of the high risk for pseudoaneurysm rupture. The AVF and pseudoaneurysms were treated successfully by percutaneous transluminal embolization; renal function remained stable after embolization.  相似文献   
40.
The authors created the glans penis augmentation by injectable hyaluronic acid gel and reported the 6-month result for premature ejaculation. In a total of 38 patients, long-term effects of 5 years were compared to those of 6 months in terms of residual volume of implants and efficacy on premature ejaculation. Maximal glandular circumference measured by tapeline significantly decreased by 15% (P<0.05) but mean patient's visual estimation (Gr 0-Gr 4) did not decrease (3.60 vs 3.56, P>0.05). Compared to 6-month follow-up, intravaginal ejaculatory latency time and vibratory threshold decreased at 5 years (P<0.05), but still well increased considering those of preaugmentation. Hence, 76% of patients and 63% of partners were still satisfied. There was no serious adverse reaction. In the 5-year long-term follow-up of glans penis augmentation by filler, the implants were well maintained and effective for glans penis hypersensitivity in premature ejaculation patients.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号