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61.
62.
OBJECTIVE: To evaluate the prognostic significance of low serum E2 concentrations in controlled ovarian hyperstimulation (COH) cycles for IVF. DESIGN: Retrospective study. SETTING: Assisted conception unit of a university hospital. PATIENT(S): One thousand four hundred and forty patients undergoing COH for IVF. INTERVENTION(S): COH, serum E2 measurement, ultrasonographic scanning of ovarian follicles, oocyte retrieval, and ET. MAIN OUTCOME MEASURE(S): Cancellation and pregnancy rates. RESULT(S): Patients were classified into four groups according to serum E2 levels on the sixth day of COH: group A (E2 level < 50 pg/mL [114 cycles]), group B (E2 level 51-100 pg/mL [189 cycles]), group C (E2 level 101-200 pg/mL [320 cycles]), and group D (E2 level >200 pg/mL [817 cycles]). Group A experienced the highest cancellation rates (65.1%) and lowest pregnancy rates (7.8%) despite requiring significantly more hMG ampules (47.8+/-1.7). The cancellation rate was higher (75.1%) and no pregnancy occurred in a subset of group A in whom COH was initiated with > or =3 ampules (225 IU) of gonadotropins. CONCLUSION(S): In COH cycles using luteal phase buserelin, low initial serum E2 concentrations are associated with poor outcome. 相似文献
63.
Assisted hatching (AH) was developed as a possible solution to repeated implantation failure. The aim of this analysis was to examine the relationship between the morphology of embryos in a previous cycle on outcome in a subsequent cycle with AH. A total of 175 AH cycles performed after previous failed ART without hatching were divided into group A with optimal and group B with suboptimal embryos transferred previously. The groups were similar in terms of demographic and cycle characteristics. In group A, there was a significant improvement (p<0.001) in implantation (28.8 vs 5.1%), clinical pregnancy (41.9 vs 12.1%) and live birth rate (38.5 vs 8.6%) compared with group B. The data suggest that the prognosis for treatment is better if AH is performed after failure despite optimal embryos compared with failure associated with suboptimal embryos and embryo quality is the most significant factor affecting outcome. 相似文献
64.
Fishleigh RV Fox KR Khalaf AI Pitt AR Scobie M Suckling CJ Urwin J Waigh RD Young SC 《Journal of medicinal chemistry》2000,43(17):3257-3266
Four new ligands that bind to the minor groove of DNA have been designed, synthesized, and evaluated by DNA footprinting. Two of the ligands are polyamides containing central regions with five or six N-methylpyrrole units, conferring hydrophobicity and good binding affinity but without retaining the correct spacing for hydrogen bonding in the base of the minor groove. The two remaining ligands have central regions which are head-to-head-linked polyamides, in which the linker is designed to improve the phasing of hydrogen bonding of the ligand with the floor of the minor groove. The highest affinity was obtained with the two polypyrroles without headgroup spacers, indicating that H-bond phasing is secondary in determining affinity compared to the major hydrophobic driving force. With a dimethylaminoalkyl group, representing a moiety with modest base strength, at both ends, water solubility is good and pH-partition theory predicts that penetration through lipid membranes will be enhanced, compared to strongly basic amidine analogues of the alkaloid precursors. All four compounds bind to DNA, with strong selectivity for AT sequences but some tolerance of GC base pairs and subtle individual preferences. The data show that very high affinities can be anticipated for future compounds in this series, but drug design must take account of overall physicochemical properties as well as the details of hydrogen bonding between ligands and the floor of the minor groove. 相似文献
65.
66.
Ban H. Khalaf 《Saudi Pharmaceutical Journal》2010,18(1):41-44
The present study was designed to evaluate the relationship between serum leptin levels and the hormones related to fertility in Iraqi females with polycystic ovary syndrome (PCOS) and marital status. This study was conducted during the period from July to December 2007. Twenty-four women (12 married and 12 unmarried) with PCOS and not maintained on any type of therapy were included in the study. Twelve healthy and normal ovulatory women with an age range matched with that of PCOS women were included. After an overnight fasting, blood samples were drawn from all women at random days. While in those with regular menstrual cycles, blood samples were obtained during the follicular phase of the cycle, except for samples utilized for the assay of progesterone that performed in the day 21 of the cycle (luteal phase). After preparation of serum, the levels of leptin, luteinizing hormone (LH), follicle-stimulation hormone (FSH), progesterone, testosterone and prolactin were analyzed. Both groups of PCOS patients showed significantly lower levels of serum leptin, while prolactin, LH and FSH and testosterone were significantly elevated compared to controls. No significant differences were reported among PCOS patients with different marital status. In conclusion, impaired plasma leptin levels in PCOS women were associated with impaired endocrinological parameters related to fertility. 相似文献
67.
68.
Hanaa Dakour Aridi Isibor Arhuidese Melissa Scudder Thomas Reifsnyder Mahmoud B. Malas 《Journal of vascular surgery》2018,67(5):1606-1612.e4
Objective
Arteriovenous grafts (AVGs) remain reliable substitutes for permanent hemodialysis access in scenarios that preclude the placement of native arteriovenous fistulas (AVFs). The majority of AVGs are constructed of expanded polytetrafluoroethylene (ePTFE), which is relatively inexpensive and readily available, but synthetic AVGs have poor patency rates. On the other hand, biologic grafts confer an advantage by virtue of their inherent similarity to the native human vasculature. However, evidence to support the current preference of synthetic conduits over biologic grafts in clinical practice is scarce. The aim of this protocol is to propose a contemporary re-evaluation and comparison between ePTFE and bovine carotid artery (BCA) grafts.Methods
This prospective randomized controlled trial is being conducted at an academic hospital center. A total of 100 patients at least 18 years of age and undergoing AVG placement will be recruited and prospectively randomized into two parallel groups with a 1:1 allocation ratio. Patients eligible to receive AVF and those with a known allergic reaction or history of intolerance to any ePTFE or BCA component will not be included in the study. Moreover, patients with a recent active infection at the site of previous AVG placement and patients with a bleeding disorder, an active malignant disease, or a life expectancy <1 year or who refuse blood transfusion and pregnant women will be excluded. Patients will receive either BCA (experimental) or standard ePTFE grafts (control) in compliance with the National Kidney Foundation Kidney Disease Outcomes Quality Initiative guidelines for AVG creation. Primary end points include primary, primary assisted, secondary, and functional patency at 1 year and 2 years after graft placement. Secondary outcomes include complications (pseudoaneurysms, infections, and steal syndrome) and reintervention rates during the first and second postoperative years. Outcomes will be assessed and documented every 6 months.Results
Once the study is completed, analysis of the data will be performed using univariate methods, and Kaplan-Meier and multivariate Cox proportional regression analyses will be employed to evaluate and to compare outcomes between BCA and ePTFE over time.Conclusions
The creation of a functional and durable dialysis vascular access is crucial in the treatment of patients with end-stage renal disease and is a challenging quest for vascular surgeons. The proposed study compares the outcomes of synthetic and biologic AVG options in patients who are poor candidates for a native AVF. This will help derive contemporary evidence and improve the care of vascular access patients. 相似文献69.
Abdulrahman Hamad Al-Abdulwahhab Abdulaziz Mohammad Al-Sharydah Sari Saleh Al-Suhibani Saeed Ahmad Al-Jubran Ali Khalaf Al-Haidey Abdulkhaliq Ibrahim Al-Hifzi Wissam Al-Issawi 《Patient safety in surgery》2018,12(1):28
Background
Spinal myelitis is an infrequent manifestation of spinal cord infection. It is caused by the Schistosoma species, which are endemic in South America, part of the Middle East, and Africa.Case presentation
We report the case of a 13-year-old male adolescent complaining of progressive lower back pain and weakness of the lower extremities for 3 days. Initial magnetic resonance imaging revealed typical transverse myelitis. Subsequently, parasite serology showed a markedly elevated level of Schistosoma antibody titers, and cerebrospinal fluid analysis yielded normal results. Because of our presumptive diagnosis of neuroschistosomiasis, the patient was prescribed an empirical regimen of an anti-parasitic agent, after which his neurological deficit promptly subsided. The patient was followed for 1 year and showed a complete long-term resolution of symptoms.Conclusions
This case highlights the increasing prevalence of neuroschistosomiasis in recent years, particularly in patients with a history of travel to endemic regions. Moreover, the study reports the clinicoradiological features of this enigmatic disorder. This rare occurrence potentiates further studies to address unanswered questions about neuroschistosomiasis.70.
Synthesis and antimicrobial evaluation of some new cyclooctanones and cyclooctane-based heterocycles
The versatile synthon (E)-2-((dimethyl amino)methylene)cyclooctanone (2) was used as a key intermediate for the synthesis of cyclooctanones and cyclooctane-based heterocycles with pyrazole, isoxazole, pyrimidine, pyrazolopyrimidine, triazolopyrimidine and imidazopyrimidine derivatives via its reactions with several nitrogen nucleophiles. The newly synthesized compounds were screened in vitro for their antimicrobial activity against pathogenic microorganisms (Listeria monocytogenes, methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans). Most of the tested compounds showed moderate to high antibacterial and antifungal effects against the tested pathogenic microorganisms. Among the synthesized compounds, 2-((p-sulfonamidophenyl)methylene)cyclooctanone (5) showed excellent activity against Listeria monocytogenes. 相似文献