全文获取类型
收费全文 | 177257篇 |
免费 | 1149篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 1142篇 |
儿科学 | 6660篇 |
妇产科学 | 3126篇 |
基础医学 | 16705篇 |
口腔科学 | 1679篇 |
临床医学 | 12616篇 |
内科学 | 31106篇 |
皮肤病学 | 669篇 |
神经病学 | 16575篇 |
特种医学 | 8973篇 |
外科学 | 29024篇 |
综合类 | 2340篇 |
一般理论 | 3篇 |
预防医学 | 18340篇 |
眼科学 | 2787篇 |
药学 | 9605篇 |
中国医学 | 624篇 |
肿瘤学 | 16434篇 |
出版年
2021年 | 42篇 |
2020年 | 36篇 |
2019年 | 48篇 |
2018年 | 21946篇 |
2017年 | 17396篇 |
2016年 | 19540篇 |
2015年 | 931篇 |
2014年 | 835篇 |
2013年 | 827篇 |
2012年 | 6995篇 |
2011年 | 21044篇 |
2010年 | 18833篇 |
2009年 | 11558篇 |
2008年 | 19549篇 |
2007年 | 21732篇 |
2006年 | 587篇 |
2005年 | 2194篇 |
2004年 | 3408篇 |
2003年 | 4391篇 |
2002年 | 2522篇 |
2001年 | 335篇 |
2000年 | 488篇 |
1999年 | 217篇 |
1998年 | 232篇 |
1997年 | 223篇 |
1996年 | 118篇 |
1995年 | 115篇 |
1994年 | 112篇 |
1993年 | 89篇 |
1992年 | 110篇 |
1991年 | 159篇 |
1990年 | 193篇 |
1989年 | 137篇 |
1988年 | 128篇 |
1987年 | 103篇 |
1986年 | 84篇 |
1985年 | 95篇 |
1984年 | 63篇 |
1983年 | 46篇 |
1982年 | 50篇 |
1980年 | 56篇 |
1979年 | 40篇 |
1978年 | 36篇 |
1974年 | 39篇 |
1970年 | 43篇 |
1969年 | 43篇 |
1968年 | 32篇 |
1938年 | 60篇 |
1932年 | 56篇 |
1930年 | 46篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Morimoto K Sakaguchi H Tanaka T Yamamoto K Anai H Hayashi T Satake M Kichikawa K 《Cardiovascular and interventional radiology》2008,31(5):981-985
The purpose of this study was to investigate the pharmacological advantages of transarterial chemoembolization (TACE) with
cisplatin powder for hypervascular hepatic tumors in animal experiments. VX2 tumors were transplanted to the livers of nine
rabbits. Cisplatin (1 mg/kg) was infused into the proper hepatic artery. In the cisplatin-HAI group, cisplatin solution was
infused. In the cisplatin-GS-TACE group, after infusion of cisplatin solution, gelatin sponge particles were used for embolization.
In the cisplatin-Lp-TACE group, after infusion of a cisplatin powder and lipiodol (10 mg/ml) suspension, gelatin sponge particles
were used for embolization. Before and after administration, platinum concentrations in plasma were measured. Using liver
specimens that were excised 60 min after infusion, platinum concentrations in tumorous and nontumorous liver tissues were
measured. The mean platinum concentration in tumorous tissue was 0.88 μg/ml for the cisplatin-HAI group, 1.23 μg/ml for the
cisplatin-GS-TACE group, and 12.65 μg/ml for the cisplatin-Lp-TACE group. The platinum concentration for the cisplatin-Lp-TACE
group was significantly higher than that for the cisplatin-HAI group (p = 0.004) and the cisplatin-GS-TAE group (p = 0.004). The mean platinum concentration in nontumorous liver tissue was 0.98 μg/ml for the cisplatin-HAI group, 1.13 μg/ml
for the cisplatin-GS-TACE group, and 1.09 μg/ml for the cisplatin-Lp-TACE group; no significant differences were seen. At
both 5 and 10 min after infusion, the platinum concentrations for the cisplatin-Lp-TACE group were lower than those for the
other two groups. The present results suggest that TACE using cisplatin powder/lipiodol suspension and gelatin sponge for
hypervascular hepatic tumors has a number of pharmacological advantages.
This material was presented at 2007 CIRSE. 相似文献
992.
Popliteal venous aneurysm is a rare cause of recurrent pulmonary embolism, although the true incidence of aneurysm is probably
underestimated. One-third of patients suffer further embolic events despite therapeutic anticoagulation. We report the case
of a 59-year-old male who presented with recurrent PEs over a period of 12 years despite anticoagulation therapy. A thrombophilia
screen and abdominal ultrasound were normal at that time. He reattended with recurrent pulmonary emboli, left calf swelling,
and a mass in his left popliteal fossa causing limitation of knee movement. Venous duplex and MRI of his popliteal fossa demonstrated
a thrombosed true popliteal venous aneurysm with popliteal and superficial femoral vein occlusion. In view of the mass effect
we proceeded to surgical excision of his aneurysm after prophylactic placement of an IVC filter. The patient regained normal
knee function with intensive inpatient physiotherapy. He has been recommenced on lifelong anticoagulant. The presentation,
investigation, and management of the condition are briefly discussed. We suggest that a bilateral lower limb duplex is performed
to exclude venous aneurysm in all patients presenting with pulmonary embolism in which an underlying source cannot otherwise
be identified and no thrombophilic tendency is detected. 相似文献
993.
Cameriere R Ferrante L De Angelis D Scarpino F Galli F 《International journal of legal medicine》2008,122(6):493-497
This paper concerns a method for assessing adult age based on the relationship between age and the third molar maturity index
(I3M), which is related to the measurement of the open apices of the third molar. Furthermore, this method was compared to those
based on Demirjian’s stages G and H. The sample consisted of 906 Caucasian individuals aged between 14 and 23 years (53.6%
females and 46.4% males). Orthopantomographs were analyzed by two observers and calibrated by means of the concordance correlation
coefficient for the reproducibility of the third molar maturity index (I3M) and κ statistics for reproducibility of the Demirjian stages. Probabilities for an individual to be older than 18 years
of age (adult age) were derived using the measurements of the third molar maturity index (I3M). These results were exploited to set out a threshold value to assign an individual to juvenile or adult age. A cutoff value
of I3M = 0.08 was taken. The sensitivity of this test was 70% and specificity was 98%. Furthermore, the proportion of individuals
with a correct classification was 83%. The results of the test showed a better specificity when compared to the choice of
stage G and a better sensitivity when compared to the choice of stage H for adult age. 相似文献
994.
995.
Objective We determined the glucose metabolism and computed tomographic (CT) density of the normal prostate gland in relation to age
and prostate size on [F-18] fluorodeoxyglucose positron emission tomography (PET)-CT.
Methods We determined the CT density (Hounsfield Units, HU) and glucose metabolism (standardized uptake value, SUV) of the normal
prostate in 145 men (age range 22–97 years) on PET-CT scans which were performed for indications unrelated to prostate pathology.
Correlations among SUV, HU, prostate size, and age were calculated using Pearson’s correlation coefficients, scatter plots,
and linear regression trend lines. The SUV and HU values were also compared among different primary cancer types using the
Kruskal-Wallis test.
Results The population average and range of the normal prostate size were 4.3 ± 0.5 cm (mean ± SD) and 2.9–5.5 cm, respectively. The
population average of mean and maximum CT densities was 36.0 ± 5.1 HU (range 23-57) and 91.7 ± 20.1 HU (range 62-211), respectively.
The population average of mean and maximum SUV was 1.3 ± 0.4 (range 0.1–2.7) and 1.6 ± 0.4 (range 1.1–3.7), respectively.
Mean SUV tended to decrease as the prostate size increased (r = −0.16, P = 0.058). Higher mean HU was correlated with higher mean SUV (r = 0.18, P = 0.033). The strongest association was observed between age and prostate size. The prostate gets larger as age increases
(r = 0.32, P < 0.001). Prostate mean SUV, max SUV, mean HU, and max HU were not significantly different among different types of primary
cancers.
Conclusions Although the normal prostate size increases with age, it does not significantly affect the gland’s metabolism and CT density,
and therefore age-correction of these parameters may be unnecessary. 相似文献
996.
Vogl TJ Lehnert T Zangos S Eichler K Hammerstingl R Korkusuz H Lindemayr S 《European radiology》2008,18(11):2449-2455
To evaluate tumor response after treating unresectable lung metastases with transpulmonary chemoembolization (TPCE) in palliative
intention. From 2001 to 2005, 52 patients (mean: 59.8 years; 32 males/20 females) suffering from 106 unresectable lung metastases
(mean:6 metastases/patient; range,1–21) were treated with 2–10 TPCE-sessions (mean: 3.3 sessions/patient). Metastases originated
from primaries, including colorectal carcinoma (n = 20), breast cancer (n = 6), renal cellular carcinoma (n = 5), thyroid
cancer (n = 4), cholangiocellular carcinoma (n = 2), leiomyosarcoma (n = 2), and others (n = 13). Tumor-feeding pulmonary
arteries were selectively probed after puncturing the femoral vein, and administering 10 ml lipiodol, mitomycin C, and microspheres
(Spherex) each via balloon catheter over pulmonary approach. During therapy, follow-up was accomplished at 4-week intervals
using unenhanced and contrast-enhanced CT. After sequential therapy, follow-up was performed every 3 months for a period of
6 months up to 2.25 years. All patients tolerated the treatments well without major side effects or complications. In 24%
(n = 13) moderate to high lipiodol uptake was found, while 75% (n = 39) of the tumors showed a low uptake. According to the
RECIST criteria, “partial response” was achieved in 16 cases, “stable disease” in 11 cases, and “progressive disease” in 25
cases [mean survival: 17 months/median: 21.1 months (Kaplan-Meyer)]. According to these findings, TPCE is a well-tolerated
procedure for palliative treatment of unresectable lung metastases. 相似文献
997.
Juan P. Gambini Juan J. López Lerena Adriana Quagliata Juan C. Hermida Carlos Heuguerot Omar Alonso 《Annals of nuclear medicine》2008,22(9):817-819
Disease status assessment of neuroblastoma patients requires computed tomography (or magnetic resonance imaging), bone scan,
metaiodobenzylguanidine (MIBG) scan, bone marrow tests, and urine catecholamine measurements. There is no clinical experience
concerning the evaluation of these patients by means of technetium-99m (99mTc)-somatostatin analog scintigraphy. Furthermore, these radiopharmaceuticals are promising imaging agents owing to their
lower cost, availability, dosimetry, and ease of preparation. An 8-year-old boy already diagnosed with stage-IV neuroblastoma
received chemotherapy. In the follow-up, after obtaining the parents’ informed consent, iodin 131 (131I)-MIBG and 99mTc-6-hydrazinopyridine-3-carboxylic acid (HYNIC)-octreotide scans were done on separate days to evaluate tumor extension.
Even as the 131I-IBG scan showed mild diffuse uptake in the projection of both lung hili, the 99mTc-HYNIC-octreotide scan showed multiple axial and appendicular bone uptakes and paravertebral, abdominal, mediastinal, and
supraclavicular ganglionar uptakes. The 99mTc-HYNIC-octreotide showed much more lesion extension than the 131I-MIBG. Therefore, 99mTc-HYNIC-octreotide may be a promising radiopharmaceutical for the evaluation of neuroblastoma patients. This finding justifies
the pre liminary evaluation of this tracer in the context of a clinical trial. 相似文献
998.
Aarvold A Wales L Papadakos N Munneke G Loftus I Thompson M 《Cardiovascular and interventional radiology》2008,31(4):821-823
Arterio-ureteric fistulae are rare but can be associated with significant morbidity and mortality. We describe a novel case
in which an arterio-ureteric fistula occurred as a complication following external iliac artery angioplasty and stenting,
in a patient who had undergone previous pelvic surgery, radiotherapy, ureteric stenting, and urinary diversion surgery. Prompt
recognition enabled successful endovascular management using a covered stent. 相似文献
999.
Panagiotis Georgoulias Chara Tzavara Nikolaos Demakopoulos Stavroula Giannakou Varvara Valotassiou Ioannis Tsougos Petros Xaplanteris Ioannis Fezoulidis 《Annals of nuclear medicine》2008,22(10):899-909
Objective Percutaneous transluminal coronary angioplasty is a well-established therapeutic method in selected patients with coronary
artery disease. The aim of this study was to assess the incremental prognostic value of technetium-99m (99mTc)-tetrofosmin myocardial gated-single- photon emission computed tomography (SPECT) in asymptomatic patients after coronary
artery stenting.
Methods A total of 246 consecutive patients (aged 55.5 ± 8.2 years, 182 men) participated in the study with a median follow-up of
9.5 years (interquartile ra 5.8–10.5 years). All patients underwent exercise gated-SPECT myocardial imaging within 5–7 months.
Myocardial scintigrams were performed using 99mTctetrofosmin, and were evaluated calculating the summed stress score (SSS),
summed rest score (SRS), and summed difference score (SDS) indexes. Cardiovascular death and non-fatal myocardial infarction
were considered as hard cardiac events, and late revascularization (>3 months after myocardial SPECT) procedures as soft events.
Receiver-operating characteristic (ROC) analysis was used to test the prognostic ability of SSS and SDS for cardiac events.
Cox proportional hazards models were used to evaluate the incremental value of SPECT variables.
Results Cardiac death occurred in 12 (4.9%) patients and non-fatal myocardial infarction in 20 (8.1%) patients. In addition, 60 (24.4%)
patients underwent a late revascularization procedure. Using ROC analysis the optimal cut-offs of SSS (AUC = 0.94; 95% CI
0.92–0.97) and SDS (AUC = 0. 76; 95% CI 0.70–0.82) for the prediction of cardiac events were 10 and 1.7, respectively. Multiple
Cox regression analyses revealed that SSS > 10 (HR = 24.2; 95% CI 7.44–78.79) and SDS > 1.7 (HR = 2.72; 95% CI 1.23–6.00)
provided incremental prognostic value over clinical and exercise test data for the composite end points of any cardiac event.
Conclusions
99mTc-tetrofosmin myocardial gated- SPECT, performed 6 months post-percutaneous coronary intervention (PCI), provides incremental
prognostic information for the prediction of cardiac events in asymptomatic patients after PCI. 相似文献
1000.
CT-guided percutaneous laser photocoagulation of osteoid osteomas of the hands and feet 总被引:1,自引:0,他引:1
Percutaneous local ablation of osteoid osteoma has largely replaced surgery, except in the small bones of the hands and feet.
The objective of this study was to describe the technical specificities and results of computed tomography (CT)-guided percutaneous
laser photocoagulation in 15 patients with osteoid osteomas of the hands and feet. We retrospectively examined the medical
charts of the 15 patients who were treated with CT-guided percutaneous laser photocoagulation therapy at our institution between
1994 and 2004. The 15 patients had a mean age of 24.33 years. None of them had received any prior surgical or percutaneous
treatment for the osteoid osteoma. The follow-up period was 24 to 96 months (mean, 49.93). The pain resolved completely within
1 week. Fourteen patients remained symptom-free throughout the follow-up period; the remaining patient experienced a recurrence
of pain after 24 months, underwent a second laser photocoagulation procedure, and was symptom-free at last follow-up 45 months
later. No adverse events related to the procedure or to the location of the tumor in the hand or the foot were recorded. CT-guided
percutaneous laser photocoagulation is an alternative to surgery for the treatment of osteoid osteomas of the hands and feet. 相似文献