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81.
Guaianolides from Lactuca saligna 总被引:1,自引:0,他引:1
The phytochemical investigation of the aerial parts of LACTUCA SALIGNA L. revealed the presence of lactucin, lactucopicrin, and a new guaianolide named 11beta,13-dihydrolactucopicrin. The structural configuration was established through spectral data. 相似文献
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Cai Grau Jai Prakash Agarwal Kaukab Jabeen Abdul Rab Khan Sarath Abeyakoon Tatiana Hadjieva Ibrahim Wahid Sedat Turkan Hideo Tatsuzaki Ketayun A Dinshaw Jens Overgaard 《Radiotherapy and oncology》2003,67(1):17-26
BACKGROUND AND PURPOSE: Single agent mitomycin c (MMC) has been shown to improve the outcome of radiotherapy in single institution trials. In order to confirm these findings in a broader worldwide setting, the International Atomic Energy Agency (IAEA) initiated a multicentre trial randomising between radiotherapy alone versus radiotherapy plus MMC. MATERIAL AND METHODS: Patients with advanced head and neck cancer were treated with primary curative radiotherapy (66 Gy in 33 fractions with five fractions per week) +/-a single injection (15 mg/m(2)) of MMC at the end of the first week of radiotherapy. Stratification parameters were tumour localization, T-stage, N-stage, and institution. A total of 558 patients were recruited in the trial from February 1996 to December 1999. Insufficient accrual and reporting led to the exclusion of three centres. The final study population consisted of 478 patients from seven centres. Patients had stage III (n=223) or stage IV (n=255) squamous cell carcinoma of the oral cavity (n=230), oropharynx (n=140), hypopharynx (n=65) or larynx (n=43). Prognostic factors like age, gender, site, size, differentiation and stage were well balanced between the two arms. RESULTS: The haematological side effects of MMC were very modest (<5% grade 3-4) and did not require any specific interventions. Furthermore, MMC did not enhance the incidence or severity of acute and late radiation side effects. Confluent mucositis and dry skin desquamation was common, occurring in 56% and 62% of patients, respectively. The overall 3-year primary locoregional tumour control, disease-specific and overall survival rates were 19, 36 and 30%, respectively. Gender, haemoglobin drop, tumour site, tumour and nodal stage were significant parameters for loco-regional tumour control. There was no significant effect of MMC on locoregional control or survival, except for the 161 N0 patients, where MMC resulted in a better loco-regional control (3-year estimate 16% vs. 29%, P=0.01). CONCLUSIONS: The study did not show any major influence of MMC on loco-regional tumour control, survival or morbidity after primary radiotherapy in stage III-IV head and neck cancer except in N0 patients where loco-regional control was significantly improved. 相似文献
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M Cherine K Khalil N Hassanein H Sholkamy M Breebaart A Elnoury 《International journal of gynaecology and obstetrics》2004,87(1):54-58
OBJECTIVES: The study describes normal labor practices in an Egyptian teaching hospital for the first time, where postpartum hemorrhage is the leading cause of maternal mortality. Third-stage management patterns are described and compared to evidence-based medicine. Reasons for third-stage practices observed are explored. STUDY DESIGN: 176 normal births were directly observed. Women were interviewed postpartum and study findings were shared with providers. RESULTS: Third-stage active management was correctly done for 15% of women observed. Most common deviations for the remaining 85% were: giving uterotonic drugs after placental delivery (65%) and without cord traction (49%). Passive management was not done for any observed delivery. CONCLUSIONS: The preventive role actively managing the third stage can provide against postpartum hemorrhage was lost to the majority of the deliveries observed. Obstacles to adopting protocols shown to reduce hemorrhage should be explored, given the contribution of postpartum hemorrhage to maternal deaths in Egypt. 相似文献
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Abdelrahman M. Elhusseiny Ali A. Khalil Reem H. El Sheikh Mohammad A. Bakr Mohamed Gaber Eiss Yasmine M. El Sayed 《国际眼科》2019,12(10):1618-1628
We reviewed the literature for different diagnostic approaches for dry eye disease (DED) including the most recent advances, contradictions and promising diagnostic tools and technique. We performed a broad literature search for articles discussing different methods for diagnosis of DED including assessment of tear osmolarity, tear film stability, ocular biomarkers and others. Articles indexed in PubMed and google scholar were included. With the growing cosmetic industry, environmental pollution, and booming of digital screens, DED is becoming more prevalent. Its multifactorial etiology renders the diagnosis challenging and invites the emergence of new diagnostic tools and tests. Diagnostic tools can be classified, based on the parameter they measure, into tear film osmolarity, functional visual acuity, tear volume, tear turnover, tear film stability, tear film composition, ocular biomarkers and others. Although numerous methods exist, the most accurate diagnosis can be reached through combining the results of more than one test. Many reported tests have shown potential as diagnostic/screening tools, however, require more research to prove their diagnostic power, alone or in combination. Future research should focus on identifying and measuring parameters that are the most specific to DED diagnosis. 相似文献
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Zeinab Khalil George M. Georgiou Henry Ogedegbe Robert E. Cone Faye Simpson Colin H. Little 《Archives of environmental & occupational health》2013,68(5):304-318
T-cell-derived antigen-binding molecules (TABMs) specific for benzoic acid were isolated from the serum of a toluene-sensitive patient. The resulting purified TABMs (BA-TABMs) did not contain immunoglobulin G and were associated with the cytokine transforming growth factor-β (TGF-β). BA-TABMs bound to benzoic acid conjugated to human serum albumin (BA-HSA), as well as to other chemicals conjugated to human serum albumin—including dinitrophenol and oxazolone. The binding of BA-TABMs to the conjugated chemicals increased the level of detectable TGF-β, and a similar effect was observed with the unconjugated chemicals, benzoic acid and 2,4-dinitrophenol glycine. The increase in TGF-β was critically dependent on the ratio between BA-TABMs and the conjugated or unconjugated chemicals; the increase was optimum at intermediate concentrations and absent at low and high concentrations. The authors used an established animal model in vivo and demonstrated that TGF-β enhanced the inflammatory response induced by the release of neuropeptides from sensory nerves; this enhancement occurred in a dose-dependent manner. The BA-TABMs also enhanced this neurogenic inflammatory response in a dose-dependent manner, and this effect was blocked by anti-TGF-β antibody. When the authors added either BA-HSA or benzoic acid, the effect of BA-TABMs on neurogenic inflammation was further enhanced at intermediate concentrations of antigen and was unaltered or reduced at higher concentrations. TABMs specific to particular chemicals, as a result of their association with cytokines (e.g., TGF-β), may be implicated in symptom production in chemically sensitive patients. 相似文献
89.
Hafiz Muhammad Shoaib Ambreen Gul Muazzam Asif Mir Suk-Yul Jung Abdul Matin 《Parasitology research》2013,112(3):1179-1188
Acanthamoeba is an opportunistic protozoan pathogen and known to be one of the most ubiquitous organisms, play a vital role in ecosystem, and recognized to cause blinding keratitis and rare but fatal granulomatous encephalitis involving the central nervous system with a very poor prognosis. This is due to limited availability of effective anti-Acanthamoeba drugs. The objective of the present study was to determine the efficacy of methanolic plants crude extracts on the viability and biological properties of Acanthamoeba castellanii (T4 genotype) and its cytotoxic effects on human corneal epithelial cells (HCEC). Using HCEC, it was observed that Acanthamoeba exhibited binding (>90 %) and cytotoxicity (>80 %) to host cells. However, plant crude extracts remarkably inhibited more than 70 and 60 % of Acanthamoeba binding and cytotoxicity to HCEC, respectively. It was further established that crude extracts (ranging from 0.1 to 1.5 mg/ml) exhibited amoebicidal effects, i.e., >50 % of trophozoites were killed/reduced at maximum dose (1.5 mg/ml) within 1 h incubation. However, the residual subpopulation remained static over longer incubations. Furthermore, growth assay demonstrated crude extracts inhibited >50 % Acanthamoeba numbers up to 7 days. Our results confirmed that plant crude extracts has inhibitory effects on Acanthamoeba growth and viability. Overall, these findings revealed that tested plant extracts is inhibitory to Acanthamoeba properties associated with pathogenesis. To the best of our knowledge, our findings demonstrated for the first time that selected methanol plant crude extracts exhibits inhibitory effects on biological properties of Acanthamoeba without any toxic effects on HCEC cells in vitro. 相似文献
90.
Boon Chin Heng Husnain Khawaja Haider Abdul Jalil Rufaihah Eugene Kwang-Wei Sim 《Scandinavian cardiovascular journal : SCJ》2013,47(3):131-134
Of 141 hospital survivors after intracardiac repair of tetralogy of Fallot, eight died suddenly 6–23 years later. Compared with the other 133 patients, these eight were older at operation, with higher post-repair systolic right ventricular pressure and more often complete atrioventricular block; ventricular arrhythmia was diagnosed before death in three cases. In follow-up totalling 2255 patient years, the linearized rate of sudden death was 0.35%/year. The instantaneous risk of sudden death showed continuous increase with the length of follow-up. Of 80 survivors electrocardiographically evaluated 13–26 (median 20) years postoperatively, none had complete block, but 79 had complete right bundle branch block, including seven with left anterior hemiblock. Ventricular extrasystoles were recorded in 1% at rest, in 34% during exercise and in 83% during 24-hour ambulatory monitoring, with Lown Grade ≥II in 27%. Old age and possibly presence of fibrosis and/or fibroelastosis in right ventricular outflow tract muscle correlated independently with high Lown Grade. A patient with Lown grade III died suddenly 2 years after our follow-up. Old age at repair thus was associated with increased risk of late sudden death and with frequent ventricular arrhythmia in long-term survivors. 相似文献