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排序方式: 共有7795条查询结果,搜索用时 0 毫秒
41.
Amit Kumar Adhya Radhika Srinivasan Firuza D Patel 《International journal of gynecological pathology》2006,25(3):281-287
BACKGROUND AND PURPOSE: Radiation therapy (RT) for cancer induces cell death by apoptosis. The major apoptotic regulatory molecules include Bcl-2, Bcl-XL (antiapoptotic), and Bax (proapoptotic) proteins. Invasive squamous cell carcinoma of the cervix is mainly treated by radiation, and hence our aim was to evaluate the changes induced by RT in the apoptotic index (AI) and to correlate this to the levels of the major pro- and antiapoptotic molecules. MATERIALS AND METHODS: Paired biopsies were obtained in 30 cases of invasive carcinoma cervix before and after 10 Gy RT. The TUNEL assay was performed to detect apoptotic nuclei and Bcl-2, Bcl-XL, and Bax proteins detected by immunohistochemistry (IHC). Statistical analysis was performed using the Spearman rank correlation coefficient test. RESULTS: Following RT, there was a significant increase in the mean AI [2.25 (+/-2.28) in post-RT vs 0.90 (+/-0.53) in the pre-RT group]. Bax, a major proapoptotic protein, was significantly increased following RT (P < 0.05), whereas the antiapoptotic Bcl-XL showed a significant decrease (P = 0.006). There was no significant change in Bcl-2 expression. The Bcl-2 and Bax IHC scores and the Bcl-2/Bax ratio did not correlate with AI in the 2 groups. There was an inverse correlation of Bcl-XL to AI in the pre-RT group (P = 0.003) but not in the post-RT group. CONCLUSIONS: RT for invasive squamous cell carcinoma of cervix results in increased apoptotic cell death with the up-regulation of Bax, a proapoptotic protein, and the down-regulation of Bcl-XL, an antiapoptotic protein, without any significant change in the levels of Bcl-2. 相似文献
42.
43.
Combining gemcitabine and capecitabine in patients with advanced biliary cancer: a phase II trial. 总被引:11,自引:0,他引:11
Jennifer J Knox David Hedley Amit Oza Ron Feld Lillian L Siu Eric Chen Mahsan Nematollahi Gregory R Pond Jessica Zhang Malcolm J Moore 《Journal of clinical oncology》2005,23(10):2332-2338
PURPOSE: Biliary cancer has a poor prognosis, and chemotherapy has had little impact. The objectives of this trial were to determine the response rate, time to disease progression, survival, and safety profile of the combination of gemcitabine and capecitabine (GemCap) in patients with advanced biliary cancer. PATIENTS AND METHODS: Eligible patients had pathologically proven, locally advanced or metastatic adenocarcinoma arising from the intra- and extrahepatic bile ducts or gallbladder with no prior chemotherapy. Patients were treated on a 3-week cycle consisting of capecitabine at 650 mg/m(2) orally twice a day for 14 days and gemcitabine at a fixed dose of 1,000 mg/m(2) intravenously over 30 minutes on days 1 and 8. RESULTS: Forty-five patients were enrolled between July 2001 and January 2004. Fifty-three percent of patients had cholangiocarcinoma, 47% had gallbladder cancer, and 89% had metastatic disease. The overall objective response rate was 31%, with an additional 42% of patients with stable disease, for a disease control rate of 73%. The median overall survival time was 14 months (95% CI, 7.3 months to not available), and the median progression-free survival time was 7 months (95% CI, 4.6 to 11.8 months). This chemotherapy combination was generally well tolerated. Transient neutropenia, thrombocytopenia, fatigue, and hand-foot syndrome were commonly observed but were easily managed without discontinuing further treatment. CONCLUSION: The significant antitumor activity combined with a mild toxicity profile seen in this study argue that GemCap chemotherapy may benefit patients with advanced biliary cancer. This regimen warrants further evaluation in a randomized study with survival and quality of life end points. 相似文献
44.
Roy Kakali Satapathy Amit Kumar Houhton Jayne A. L. Flanagan Sarah E. Radha Venkatesan Mohan Viswanathan Sharma Rajni Jain Vandana 《Indian journal of pediatrics》2019,86(11):1051-1053
Indian Journal of Pediatrics - Congenital hyperinsulinism (CHI) is a clinically and genetically heterogeneous disorder, characterized by dysregulated insulin secretion. Pathogenic variants in at... 相似文献
45.
46.
Payank Patel Amit Roy Navid Sharifi Pantcho Stoyanov Richard R. Chromik Christian Moreau 《Materials》2022,15(10)
Surface coatings that operate effectively at elevated temperatures provide compatibility with critical service conditions as well as improved tribological performance of the components. High-entropy coatings (HECs), including metallic, ceramics, and composites, have gained attention all over the world and developed rapidly over the past 18 years, due to their excellent mechanical and tribological properties. High-entropy alloys (HEAs) are defined as alloys containing five or more principal elements in equal or close to equal atomic percentage. Owing to the high configurational entropy compared to conventional alloys, HEAs are usually composed of a simple solid solution phase, such as the BCC and FCC phases, instead of complex, brittle intermetallic phases. Several researchers have investigated the mechanical, oxidation, corrosion and wear properties of high-entropy oxides, carbides, borides, and silicates using various coating and testing techniques. More recently, the friction and wear characteristics of high-entropy coatings (HECs) have gained interest within various industrial sectors, mainly due to their favourable mechanical and tribological properties at high temperatures. In this review article, the authors identified the research studies and developments in high-entropy coatings (HECs) fabricated on various substrate materials using different synthesis methods. In addition, the current understanding of the HECs characteristics is critically reviewed, including the fabrication routes of targets/feedstock, synthesis methods utilized in various research studies, microstructural and tribological behaviour from room temperature to high temperatures. 相似文献
47.
Amit Kumar Vimal Shivani Sharma Bindu Gahlawat G. Pandian Sumit Sural 《Indian Journal of Orthopaedics》2022,56(11):1897
BackgroundFlexible flat foot or pes planovalgus is a common foot deformity, and silicone and customized insole are commonly used as a non-operative treatment modality of flexible planovalgus. However, there are inadequate data and limited evidence available regarding the immediate effects of their use in midfoot and hindfoot of adults. The aim of this study is to quantify and compare the radiological parameters immediately on weightbearing with silicon and customized insoles and without them to assess the effect on midfoot and hindfoot of the flexible planovalgus in adults.MethodsA total number of 11 (8 females and 3 males) subjects with flexible pes planovalgus deformity without any other foot deformity were included in the study. Each patient was assessed three times in a random sequence without and with use of either silicon insoles or customized insole. The radiographic parameters without insole, with silicon insole, and with customized insole conditions were calculated using online available computer software Kinovea.ResultsOne-way ANOVA analysis was performed between groups (without insole, with silicone insole and with customized insole). The hindfoot parameters depicted that calcaneal inclination angle (CIA) was significant increased (P = 0.000) and talar declination angle (TDA) was significantly decreased (P = 0.003) only with the use of customized insole compared to without insole. The midfoot parameters depicted that the first metatarsal angle (FMA) and talonavicular coverage angle (TCA) were significantly lower with customized insole (P = 0.00) as compared to other two groups and significantly lower with silicone insole (P = 0.00) as compared to without insole group.ConclusionThe results imply that the compressibility of the insole material affects the forefoot and hindfoot biomechanics differently. This study concludes that silicone insole affects only the midfoot which bears 45% of bodyweight and customized insole affects both midfoot and more importantly the hindfoot which bears 55% of bodyweight. 相似文献
48.
Glycyrrhetinic acid-modified chitosan (mGA-suc-CTS) is used as liver-targeted carrier for drug delivery. In this study, nanoparticles were prepared by ionic gelation process, and glycyrrhetinic acid act as the targeting ligand. The structure of the product was confirmed by IR and NMR techniques. The main aim of this study was to deliver atorvastatin directly to the liver by using same conjugate and reduce the associated side-effects, i.e. hepatotoxicity at high dose. Characterization of the developed formulation was performed by differential scanning calorimetry, particle size measurements and cellular uptake studies. Release profile, pharmacokinetics studies and organ distribution studies showed that developed formulation shows a relative higher liver uptake. The optimized formulation showed increased plasma concentration than the CTS nanoparticles as well as plain drug and the accumulation in the liver was nearly 2.59 times more than that of obtained with the CTS nanoparticles. Pharmaceutical and pharmacological indicators suggested that the proposed strategy can be successfully utilized for liver targeting of therapeutics. 相似文献
49.
We hypothesized that prolonged bedside limited-channel amplitude-integrated electroencephalogram (aEEG) monitoring following a standard 1-hour conventional electroencephalogram (cEEG) would increase the detection of subclinical seizures and allow continuous evaluation of the background EEG in neonatal encephalopathy. This may identify complementary roles for these EEG technologies in neonatal units where continuous cEEG monitoring may not be readily available. We prospectively recruited 25 term neonates with a diagnosis of neonatal seizures or encephalopathy. All infants underwent a standard 1-hour cEEG followed by 12 to 24 hours of aEEG monitoring. Data from the aEEG (plus the raw signal) were analyzed by an epileptologist and compared with information obtained from the clinical report of the cEEG. aEEG and cEEG data were available for 24 infants. Results from magnetic resonance imaging (MRI) performed at 7 to 10 days of life were available in 23/24 infants. Background classification on cEEG and aEEG was similar in 83% of patients. Five of 24 infants had normal background on cEEG. Prolonged aEEG detected evolution of background from initially normal to moderately abnormal in an additional four infants. It also detected more subclinical seizures than the 1-hour cEEG in 8/14 infants. Normal background on aEEG and cEEG was associated with normal MRI results, and severe background abnormality (5/24) on both aEEG and cEEG was associated with abnormal MRI results. Data obtained from prolonged aEEG (plus raw EEG) provide similar background activity, enhance seizure detection, and complement standard cEEG in predicting short-term outcomes, based on MRI, in term neonates with seizures or encephalopathy. Limited-channel aEEG technology may provide a pragmatic alternative for longitudinal monitoring of newborn infants with encephalopathy in neonatal units where prolonged video EEG monitoring is not feasible. 相似文献
50.
Erez O Mayer A Shoham-Vardi I Dukler D Mazor M 《Archives of gynecology and obstetrics》2008,277(4):311-317
Objective To determine the prevalence of pregnancy complications among primiparous patients with twin gestation in our population and
to investigate the association between the increased rates of assisted reproduction (ART) in twin gestation and preterm birth
(PTD).
Material and methods A retrospective population based cohort study was designed, including all twin deliveries after 24 weeks gestation (n = 2,601). The study group included 666 primiparous women and the comparison group 1,935 multiparous women. Maternal characteristics
and perinatal outcome were evaluated. Women with fetal malformations were excluded. A multiple logistic regressions analysis
for independent risk factors was performed including factors that were significantly different between the study groups in
the univariate analysis. Patient’s data were obtained from computerized database and analyzed using SPSS statistical package.
Results Primiparous women had a significantly higher rate of preeclampsia, chronic hypertension, ART, prelabor rupture of membranes
(PROM) preterm deliveries (PTD), labor dystocia, cesarean section (CS) and vacuum extraction of the first twin than the multiparous
group. Primiparous patients had a significantly lower gestational age at delivery and neonatal birth weight of the first and
second twin. In multiple logistic regressions analysis primiparity and ART were independent risk factors for PTD, (OR 1.45,
95% CI 1.18–1.78; OR 1.36, 95% CI 1.09–1.71, respectively).
Conclusions (1) Primiparous patients with twin gestation represent a unique population with high rate of infertility and underlying diseases
such as chronic hypertension in comparison to the multiparous women with twin gestation; (2) primiparity is an independent
risk factor for prematurity in twin gestations; and (3) although primiparous women had an increased maternal complications,
neonatal mortality rates were not significantly different from multiparous women. 相似文献