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991.
Darwish T Brahma A O'Donnell C Efron N 《Journal of cataract and refractive surgery》2007,33(9):1515-1521
PURPOSE: To evaluate recovery of the corneal subbasal nerve plexus and corneal sensitivity after myopic laser in situ keratomileusis (LASIK) and laser-assisted subepithelial keratectomy (LASEK). SETTING: Manchester Centre for Vision, Royal Eye Hospital, Manchester, United Kingdom. METHODS: Thirty LASEK patients and 20 LASIK patients had slit-scanning confocal microscopy and noncontact corneal esthesiometry preoperatively and 1, 3, and 6 months after surgery. Images of the subbasal nerve plexus were analyzed using customized software to evaluate nerve regeneration. RESULTS: Central corneal sensitivity decreased significantly 1 month after LASEK and LASIK and returned to normal levels after 3 months. Corneal subbasal nerve fiber density, nerve branch density, nerve fiber length, and nerve fiber width decreased significantly 1 month after LASIK and had not returned to the preoperative levels by 6 months. Nerve fiber tortuosity decreased significantly 1 month after LASEK and returned to the preoperative levels 3 months after surgery. There were no significant differences in nerve fiber tortuosity before and after LASIK. Neither corneal sensitivity nor nerve fiber morphology was different between the 2 groups at any postoperative visit. CONCLUSIONS: Corneal sensitivity and subbasal nerve morphology were adversely affected by LASEK and LASIK. Corneal sensitivity recovered 3 months after the procedure, but subbasal nerves were still abnormal after 6 months. Despite the different forms of surgical trauma to corneal nerves with LASIK and LASEK, there was no apparent difference in the time course of recovery of corneal structure and function. 相似文献
992.
Infectious keratitis following corneal transplantation is one of the leading causes of failure of a corneal graft. The incidence of graft infection is variable, with developing countries having a higher incidence. The majority of the graft infections occur within 1 year of the corneal transplantation. Suture-related problems and persistent epithelial defect are the most common risk factors predisposing to graft infection. Pneumococcus species and Staphylococcus aureus have been found to be the commonest microorganisms in the developed world, whereas Staphylococcus epidermidis is the most often detected microorganism in corneal graft infection in the developing world. The early identification of predisposing risk factors in patients and their appropriate management at the earliest may prevent the occurrence of graft infection and might improve graft survival. Visual prognosis in eyes with post-keratoplasty graft infection is poor even after optimal therapy and there is a high rate of graft decompensation. 相似文献
993.
Galor A Ference SJ Singh AD Lee MS Stevens GH Perez VL Peereboom DM 《American journal of ophthalmology》2007,144(1):45-49
PURPOSE: To report on the development of visually significant maculopathy associated with blood-brain barrier disruption (BBBD) therapy for the treatment of central nervous system (CNS) lymphoma. DESIGN: Retrospective case series. METHODS: Chart review of 20 patients undergoing BBBD therapy for treatment of CNS lymphoma at the Cleveland Clinic. Patients with documented maculopathy were included in analysis. RESULTS: Seven (54%) of 13 patients were identified with new macular retinal pigment epithelium (RPE) changes after BBBD treatment. The RPE changes consisted of fine clumps of hyperpigmentation in the foveal region associated with variable degrees of RPE loss. These changes were bilateral but often asymmetric. Two patients had decreased visual acuity resulting from maculopathy. One patient had documented progression of maculopathy after completion of treatment. CONCLUSIONS: Maculopathy is a frequent finding after BBBD therapy for CNS lymphoma. 相似文献
994.
Patel BB Sengupta R Qazi S Vachhani H Yu Y Rishi AK Majumdar AP 《International journal of cancer. Journal international du cancer》2008,122(2):267-273
Curcumin (diferuloylmethane), which has been shown to inhibit growth of transformed cells, has no discernible toxicity and achieves high levels in colonic mucosa. 5-fluorouracil (5-FU) or 5-FU plus oxaliplatin (FOLFOX) remains the backbone of colorectal cancer chemotherapeutics, but with limited success. The present investigation was, therefore, undertaken to examine whether curcumin in combination with conventional chemotherapeutic agent(s)/regimen will be a superior therapeutic strategy for colorectal cancer. Indeed, results of our in vitro studies demonstrated that curcumin together with FOLFOX produced a significantly greater inhibition (p < 0.01) of growth and stimulated apoptosis (p < 0.001) of colon cancer HCT-116 and HT-29 cells than that caused by curcumin, 5-FU, curcumin + 5-FU or FOLFOX. These changes were associated with decreased expression and activation (tyrosine phosphorylation) of EGFR, HER-2, HER-3 (72-100%) and IGF-1R (67%) as well as their downstream effectors such as Akt and cycloxygenase-2 (51-97%). Furthermore, while these agents produced a 2-3-fold increase in the expression of IGF-binding protein-3 (IGFBP-3), curcumin together with FOLFOX caused a 5-fold increase in the same, when compared to controls. This in turn led to increased sequestration of IGF by IGFBP-3 rendering IGF-1 unavailable for binding to and activation of IGF-1R. We conclude that the superior effects of the combination therapy of curcumin and FOLFOX are due to attenuation of EGFRs and IGF-1R signaling pathways. We also suggest that inclusion of curcumin to the conventional chemotherapeutic agent(s)/regimen could be an effective therapeutic strategy for colorectal cancer. 相似文献
995.
Bailey Christopher R. Arun Anirudh Towsley Matthew Choi Won Kyu Betz Joshua F. MacKenzie Stacey Areda Moustafa Abou Duvvuri Madhavi Mitchell Sally Weiss Clifford R. 《Cardiovascular and interventional radiology》2019,42(3):389-395
CardioVascular and Interventional Radiology - To describe our institutional experience with MVP™ micro vascular plug systems for the treatment of pulmonary arteriovenous malformations... 相似文献
996.
997.
BACKGROUND CONTEXT: Previous studies have analyzed the outcome following posterior correction and combined anterior-posterior correction for Scheuermann's kyphosis. Traditionally interbody fusion has been obtained using morselized rib graft. Recently the use of titanium anterior cages has been suggested for interbody use. There are no long-term studies comparing these two techniques. PURPOSE: To investigate the potential value of titanium anterior interbody cages compared with morselized rib graft for anterior interbody fusion in combination with posterior instrumentation, correction, and fusion for Scheuermann's kyphosis. STUDY DESIGN: Nonrandomized comparison of two surgical techniques in matched subjects. PATIENT SAMPLE: Fifteen patients with identical preoperative radiographic and physical variables (age, gender, height, weight, body mass index) were managed with combined anterior release, interbody fusion, posterior instrumentation, correction, and fusion. Group A (n=8) had morselized rib graft inserted into each intervertebral disc space. Group B (n=7) had titanium interbody cages packed with bone graft inserted at each level. The posterior instrumentation extended from T2 to L2 in both groups. OUTCOME MEASURES: Preoperative and postoperative curve morphometry was studied on plain radiographs by two independent observers. The indices studied included Cobb angle, Ferguson's angle, Voutsinas index, sagittal vertical axis (SVA), sacral inclination (SI), and lumbar lordosis (LL). Interbody fusion was assessed at final follow-up. Each patient was reviewed at 3, 6, 12, 24, 48, and 60 months after surgery with standing radiographs. METHODS: Both surgical groups were compared in terms of radiological parameters and complications. Wilcoxon-matched pairs test and Mann-Whitney test were used. RESULTS: The average follow-up for Group A was 70 months and for Group B 66 months. For the whole group, the preoperative median Cobb angle for thoracic kyphosis was 86 degrees , the median Ferguson angle was 50 degrees , Voutsinas index was 28.7, SVA -3.5 centimeters, lumbar lordosis was 66 degrees , and the median sacral inclination angle was 40 degrees . The median postoperative Cobb angle was 42 degrees , Ferguson angle 28.4 degrees , Voutsinas index 13, SVA -4.0 centimeters, and the median sacral inclination angle was 34 degrees . There were significant differences between preoperative and postoperative measurements for all variables (p<.01), indicating that good correction was achieved. At 4-year follow-up, fusion criteria were satisfied in 12 of 15 cases (80%). Three patients had distal junctional kyphosis. There was no significant difference obtained in the final Cobb angle, Ferguson angle, and Voutsinas index when Group A (rib graft) was compared with Group B (titanium cage) Both Group A and B patients retained the postoperative correction achieved with respect to all the radiographic parameters studied. CONCLUSION: We were unable to demonstrate any significant advantage for the use of anterior titanium interbody cages over the use of morselized rib graft in the surgical management of Scheuermann's kyphosis. Given the not inconsiderable cost and the need for posterior chevron osteotomies when interbody cages are used, we have now reverted to our previous practice of using morselized rib graft at each intervertebral level. 相似文献
998.
Lodha R Vivekanandhan S Sarthi M Arun S Kabra SK 《Acta paediatrica (Oslo, Norway : 1992)》2007,96(3):406-409
AIM: A prospective study was conducted to determine thyroid hormone levels and their relationship to survival in children with septic shock and sepsis. METHODS: We estimated thyroid hormone levels (T3, T4, TSH, fT3 and fT4) in children with septic shock and compared with those in children with sepsis. RESULTS: Twenty-four children (13 boys) with septic shock and 25 children (14 boys) with sepsis were enrolled. The median T3, T4, fT3, fT4 and TSH (95% confidence interval) were 40 (40-40.23) ng/dL, 4.45 (1.9-6.03) microg/dL, 1.85 (1.2-2.37) pg/mL, 0.77 (0.57-0.95) ng/dL, 0.51 (0.26-1.15) microIU/mL, respectively in children with septic shock group compared with 130 (98.28-163.48) ng/dL, 9.3 (7.66-10.63) microg/dL, 3.2 (3-4.27) pg/mL, 1.3 (1.1-1.4) ng/dL, 2.85 (1.07-3.61) microIU/mL, respectively, in children with sepsis. Children with septic shock who died (n = 12) had higher TSH levels compared to those who survived (p = 0.04). There was no difference in hormone levels between children with catecholamine responsive and catecholamine resistant septic shock. CONCLUSION: Children with septic shock had lower levels of T3, T4, fT3, fT4 and TSH compared to those with sepsis. Findings of our study suggest that derangement of thyroid functions in children is not an important factor contributing to the severity of septic shock. 相似文献
999.
Jost M. Kollmeier Zhengguo Tan Arun A. Joseph Oleksandr Kalentev Dirk Voit K. Dietmar Merboldt Jens Frahm 《NMR in biomedicine》2019,32(12)
The purpose of this work was to develop an acquisition and reconstruction technique for two‐ and three‐directional (2d and 3d) phase‐contrast flow MRI in real time. A previous real‐time MRI technique for one‐directional (1d) through‐plane flow was extended to 2d and 3d flow MRI by introducing in‐plane flow sensitivity. The method employs highly undersampled radial FLASH sequences with sequential acquisitions of two or three flow‐encoding datasets and one flow‐compensated dataset. Echo times are minimized by merging the waveforms of flow‐encoding and radial imaging gradients. For each velocity direction individually, model‐based reconstructions by regularized nonlinear inversion jointly estimate an anatomical image, a set of coil sensitivities and a phase‐contrast velocity map directly. The reconstructions take advantage of a dynamic phase reference obtained by interpolating consecutive flow‐compensated acquisitions. Validations include pulsatile flow phantoms as well as in vivo studies of the human aorta at 3 T. The proposed method offers cross‐sectional 2d and 3d flow MRI of the human aortic arch at 53 and 67 ms resolution, respectively, without ECG synchronization and during free breathing. The in‐plane resolution was 1.5 × 1.5 mm2 and the slice thickness 6 mm. In conclusion, real‐time multi‐directional flow MRI offers new opportunities to study complex human blood flow without the risk of combining differential phase (i.e., velocity) information from multiple heartbeats as for ECG‐gated data. The method would benefit from a further reduction of acquisition time and accelerated computing to allow for extended clinical trials. 相似文献
1000.
Correlates and trend of HIV prevalence among female sex workers attending sexually transmitted disease clinics in Pune, India (1993-2002) 总被引:1,自引:0,他引:1
Brahme R Mehta S Sahay S Joglekar N Ghate M Joshi S Gangakhedkar R Risbud A Bollinger R Mehendale S 《Journal of acquired immune deficiency syndromes (1999)》2006,41(1):107-113
In India, substantial efforts have been made to increase awareness about HIV/AIDS among female sex workers (FSWs). We assessed the impact of awareness regarding safe sex in a cohort of FSWs by studying trends in HIV prevalence, sexually transmitted diseases (STDs), and risk behaviors measured from 1993 to 2002 in Pune, India. A total of 1359 FSWs attending 3 STD clinics were screened for HIV infection, and data on demographics, sexual behaviors, and past and current STDs were obtained. The overall HIV prevalence among FSWs was 54%. Not being married (adjusted odds ratio [AOR] = 1.74, 95% confidence interval [CI]: 1.17 to 2.59), being widowed (AOR = 2.10, 95% CI: 1.16 to 3.80), inconsistent condom use (AOR = 1.60, 95% CI: 1.02 to 2.50), clinical presence of genital ulcer disease (GUD; AOR = 1.66, 95% CI: 1.07 to 2.56), and genital warts (AOR = 4.70, 95% CI: 1.57 to 14.08) were independently associated with HIV infection among FSWs. The prevalence of HIV remained stable over 10 years (46% in 1993 and 50% in 2002; P = 0.80). The prevalence of GUD decreased over time (P < 0.001), whereas that of observed genital discharge remained stable. Reported consistent condom use as well as the proportion of FSWs who refused sexual contact without condoms increased over time (P < 0.001). These data collectively suggest that safe sex interventions have had a positive impact on FSWs in Pune, India. 相似文献