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141.
Mohammad Nishat Akhtar Muneer Khan Sher Afghan Khan Asif Afzal Ram Subbiah Sheikh Nazir Ahmad Murtuja Husain Mohammad Mursaleen Butt Abdul Rahim Othman Elmi Abu Bakar 《Materials》2021,14(10)
In the present investigation, the non-recrystallization temperature (TNR) of niobium-microalloyed steel is determined to plan rolling schedules for obtaining the desired properties of steel. The value of TNR is based on both alloying elements and deformation parameters. In the literature, TNR equations have been developed and utilized. However, each equation has certain limitations which constrain its applicability. This study was completed using laboratory-grade low-carbon Nb-microalloyed steels designed to meet the API X-70 specification. Nb- microalloyed steel is processed by the melting and casting process, and the composition is found by optical emission spectroscopy (OES). Multiple-hit deformation tests were carried out on a Gleeble® 3500 system in the standard pocket-jaw configuration to determine TNR. Cuboidal specimens (10 (L) × 20 (W) × 20 (T) mm3) were taken for compression test (multiple-hit deformation tests) in gleeble. Microstructure evolutions were carried out by using OM (optical microscopy) and SEM (scanning electron microscopy). The value of TNR determined for 0.1 wt.% niobium bearing microalloyed steel is ~ 951 °C. Nb- microalloyed steel rolled at TNR produce partially recrystallized grain with ferrite nucleation. Hence, to verify the TNR value, a rolling process is applied with the finishing rolling temperature near TNR (~951 °C). The microstructure is also revealed in the pancake shape, which confirms TNR. 相似文献
142.
143.
The sponge/Matrigel angiogenesis assay 总被引:11,自引:0,他引:11
It has become increasingly clear that definitive tests for angiogenesis require in vivo assays. Recently, the Matrigel plug assay has become the method of choice for many studies involving in vivo testing for angiogenesis. In this assay, test angiogenesis-inducing compounds such as bFGF or tumor cells are introduced into cold liquid Matrigel which, after subcutaneous injection, solidifies and permits penetration by host cells and the formation of new blood vessels. Assessment of angiogenesis in the Matrigel plug is achieved either by measuring hemoglobin or by scoring selected regions of histological sections for vascular density. We now describe a modification of the Matrigel plug assay which permits a more precise visualization of the angiogenic reaction, provides directional information, requires no histological analysis, and lends itself to photographic documentation and image analysis protocols. We illustrate the assay by describing dose- and time-dependent responses to tumors of murine and human origin, to angiogenesis-inducing factors such as bFGF (FGF-2) and VEGF and to anti-angiogenic agents such as endostatin. The method has been used as well to demonstrate blood vessel recruitment by embryonic chick aortic arch rudiments. Additionally it has been able to detect strain-dependent differences in susceptibility to angiogenic stimulation. 相似文献
144.
145.
Saad Akhtar Khan Hussain Shallwani Muhammad Shahzad Shamim Ghulam Murtaza Syed Ather Enam Reema Obaid Qureshi Muhammad Zubair Tahir 《Child's nervous system》2014,30(2):277-281
Objective
This study aimed to determine the risk factors associated with poor outcome of decompressive craniectomy (DC) for severe traumatic brain injury (TBI) in pediatric patients.Methods
This retrospective study is conducted on pediatric population (age 1–15 years) presenting with TBI who underwent DC at our institute between January 2000 and 2010. Based on Glasgow outcome score (GOS) at a minimum follow-up of 5 months, patients were divided into two groups, namely poor outcome (GOS 1, 2, and 3) and good outcome (GOS 4 and 5). Records were reviewed and analyzed for preoperative and intraoperative predictors.Results
We found 25 patients who were eligible as per selection criteria. Mean age at presentation was 6?±?4 years and there was male preponderance (84 %). Fall (60 %) was the most common mechanism of injury followed by gunshots and road traffic accident. On univariate analysis, presenting GCS ≤5 (p value?=?0.009), delay in presentation of more than 150 min (p value?=?0.010), DC performed after more than 4 h of arrival in hospital (p value?=?0.042), and intraoperative blood loss exceeding 300 ml (p value?=?0.001) were significant predictors of poor outcome.Conclusion
Our study suggests that DC in children is not only a life-saving procedure, but also leads to a good functional outcome after severe injury. However, patient selection still remains an important aspect, and the above-mentioned factors should be considered while deciding for DC to improve survival. Further prospective studies on larger sample size are warranted to validate our results. 相似文献146.
Md. Sohaib Akhtar Arshad Hafeez Khan Mohammed Fahud Khurram Imran Ahmad 《Indian Journal of Plastic Surgery》2014,47(2):221-226
Background:
Soft-tissue defects around the knees are common in injured limbs and in the same injury the leg is often involved and the thigh is spared. Furthermore due to pliable and relatively lax skin, we have used inferiorly based thigh flap to reconstruct defects around knee joint.Aims and Objectives:
The aim of this study is to evaluate the use of inferiorly based thigh flap to cover soft-tissue defects over the proximal one-third of the leg, patellar region, knee, and lower thigh.Materials and Methods:
This study was conducted during the period between October 2011 and February 2013. Inferiorly based anteromedial thigh fasciocutaneous flap was performed on 12 patients and inferiorly based anterolateral thigh fasciocutaneous flap on four patients. The sites of the soft-tissue defects included patellar regions, infrapatellar region, upper one-third of leg, lower thigh, and over the knee joint.Results:
Patients were evaluated post-operatively in terms of viability of flap, the matching of the flap with the recipient site, and donor site morbidity. All the flaps survived well except one which developed distal marginal flap loss, one in which wound dehiscence was noticed, and two in which mild venous congestion was observed. Venous congestion in two patients subsided on its own within 3 days. One patient with wound dehiscence achieved complete healing by secondary intention. Patient who developed distal flap loss required debridement and skin grafting. No appreciable donor site morbidity was encountered. Skin colour and texture of the flap matched well with the recipient site.Conclusions:
The inferiorly based thigh flap is a reliable flap to cover the defect over proximal one-third of the leg, patellar region, knee, and lower thigh.KEY WORDS: Defect around the knee joint, inferiorly based thigh flap, perforator based flap 相似文献147.
Md Sohaib Akhtar M. Fahud Khurram Rampukar Choudhary A.H. Khan Imran Ahmad 《European journal of plastic surgery》2014,37(10):547-554
Introduction
Reconstruction of distal leg region remained a difficult task. Free flaps had long been considered as a gold standard for these regions. However, due to various limitations of the free flap, a local fasciocutaneous flap could be considered as a good alternative. In this study, the use of a distally based posterior tibial artery perforator flap had been evaluated in the coverage of defects around the ankle, heel, and lower third of a leg. The study also outlined the donor-site morbidity and the technical details of the surgical procedure.Methods
In this prospective study, a total of 42 patients with distal lower leg defects were included. The defects were located on the lower third of the leg (n?=?23), ankle (n?=?11), and heel (n?=?8). Reconstruction was performed using distally pedicled posterior tibial artery perforator flaps. Patients were evaluated in terms of viability of the flap, functional gain, and donor-site morbidity. The technical details of the operative procedure have also been outlined.Results
All the flaps survived well, with the exception of one patient, who experienced complete flap loss. Minor complications were, however, noted in four other patients: One patient developed superficial epidermolysis; one developed postoperative venous congestion, which subsided within 3 days by conservative means, and in two patients, partial loss of the skin graft occurred at the donor site but healed completely with dressing and antibiotics. The patients were followed up for an average period of 6 months, ranging from 1 to 13 months. Donor-site morbidity was minimal.Conclusions
It was concluded that the distally based pedicled posterior tibial artery perforator flap was a reliable, easy, less time-consuming, and versatile procedure for covering the defects around the ankle, heel, and lower third a leg. Level of Evidence: Level IV, therapeutic study 相似文献148.
E. Rosser RN DPhil MN RM Dip N Ed Dip RM PFHEA E. Buckner RN PhD CNE AE-C FNAP T. Avedissian RN MSN D.S.K. Cheung BN MSc PhD K. Eviza RN MSN T. B. Hafsteinsdóttir RN PhD M.Y. Hsu RN PhD MSc M. N. Kirshbaum RN BSc MSc PhD GDip Health Ed Dip Onc Dip Counselling Dip CBT FHEA C. Lai RN PhD Y.C. Ng PhD J. Ramsbotham RN PhD MN S. Waweru RN MSN FNP-BC 《International nursing review》2020,67(4):484-494
149.
Umay Amara Sara Riaz Khalid Mahmood Naeem Akhtar Muhammad Nasir Akhtar Hayat Muhammad Khalid Muhammad Yaqub Mian Hasnain Nawaz 《RSC advances》2021,11(40):25084
Exploring a robust, extremely sensitive, cost-effective and reliable assay platform for the precise analysis of dopamine (DA) has become a big challenge predominantly at the clinical level. To participate in this quest, herein, we fabricated a perylene diimide (PDI) self-assembled graphitic surface of the graphitic pencil electrode (GPE) anchored copper oxide (CuO). The self-assembled N-rich PDI led to the fast movement of ions by decreasing the bandgap and improved the electron transport kinetics with more exposed catalytic active sites, thus resulting in the robust electrochemical sensing of DA. The designed sensor exhibited good sensitivity (4 μM−1 cm−2), high structural stability, repeatability and excellent reproducibility with an RSD value of 2.9%. Moreover, the developed system showed a wide linear range (5 μM to 500 μM) and reliable selectivity even in the presence of co-existing interferants, such as ascorbic acid and uric acid. The fabricated nanohybrid was eventually employed to analyze DA in spiked physiological fluids and provided satisfactory recoveries. The designed PDI-CuO based interface also showed a very low detection limit of 6 nM (S/N = 3), consequently confirming its suitability for clinical and biological applications.Exploring a robust, extremely sensitive, cost-effective and reliable assay platform for the precise analysis of dopamine (DA) has become a big challenge predominantly at the clinical level. 相似文献
150.
Rachael Purri BA Laura Brennan PhD Jacqueline Rick PhD Sharon X. Xie PhD Benjamin L. Deck BS Lana M. Chahine MD Nabila Dahodwala MD Alice Chen-Plotkin MD John E. Duda MD James F. Morley MD PhD Rizwan S. Akhtar MD PhD John Q. Trojanowski MD PhD Andrew Siderowf MD MSCE Daniel Weintraub MD 《Movement disorders》2020,35(9):1618-1625