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排序方式: 共有3005条查询结果,搜索用时 15 毫秒
21.
22.
Rectal cancer causes approximately 6000 deaths in the UK each year. The role of the surgeon in rectal cancer is to control local disease and minimise the risk of recurrence. Reconstructive rectal surgery for cancer aims to combine a safe oncological procedure with the maximum quality of life possible. An improved understanding of rectal cancer pathology allied to modern surgical techniques such as intestinal stapling guns, endoanal anastomoses and the colonic pouch has led to an increased number of sphincter saving operations being performed. We have reviewed the background, technical advances and looked at the future of reconstructive rectal surgery for rectal cancer. Firstly we discuss the work which led to low anterior resection being accepted as an oncologically safe operation. followed by an overview of surgical techniques that have facilitated low anterior resection for rectal cancer with good functional results for the patient. Lastly, we look at the role of radiotherapy and the neosphincter in reducing the need for a permanent stoma. 相似文献
23.
Epilepsy surgery has emerged as an important option in the treatment of children with epilepsy that is refractory to antiepileptic drug management. The cornerstone of successful surgery is accurate localization of the brain region of seizure onset. Traditional techniques of seizure onset localization, e.g. surface electroencephalography (EEG) recording and magnetic resonance imaging (MRI), allow accurate localization in a significant number of patients. When the focus of seizure onset is not apparent from these non-invasive techniques, other methods of localization, e.g. intracranial EEG recording, may be needed before resection of the focus. Single-photon emission computed tomography (SPECT) is a nuclear medicine blood-flow technique that has been used to identify a region of epileptogenic brain associated with low blood flow in the resting state (interictal SPECT) or increased blood flow at the time of seizure activity (ictal SPECT). This report describes the validation and utility of a computer-assisted method of subtracting the interictal from the ictal SPECT scans and co-registering the difference image on the MRI. This method, called subtraction ictal SPECT co-registered on MRI (SISCOM), is used in guiding the location and the extent of intracranial electrode implantation, or in obviating the need for the implantation in some cases. 相似文献
24.
Rawashdeh YF Mortensen J Hørlyck A Olsen KO Fisker RV Schroll L Frøkiaer J 《Scandinavian journal of urology and nephrology》2000,34(1):10-14
OBJECTIVES: To study the normal range and distribution of the resistive index (RI) and the resistive index ratio (RIR) in the non-obstructed non-dilated porcine kidney, and to assess the reliability of the threshold values RI 0.70 and RIR 1.10 as prognosticators of true obstruction in the upper urinary tracts. METHODS AND MATERIALS: Twenty female pigs of Danish land race breed were studied under general anaesthesia. Blood pressure and urine output was monitored throughout the experiment. Doppler evaluations were obtained from an interlobar artery in the lower half of each kidney, and the RI was calculated as the average of 3 x 3 cycles for each side independently. Statistical analysis of the obtained results was performed. RESULTS: Forty renal units were studied. The RI values ranged from 0.48-0.85 (mean 0.63). Nine renal units (22.5%) had RI values > or = 0.70. RIR values ranged from 1.00-1.38 (mean 1.07). Three RIR values (15%) were above 1.10. There was no statistically significant relationship between RI and laterality (p = 0.25), and no overall significant relationship between RI and mean arterial blood pressure (r2 = 0.21) or urine output (r2 = 0.004). CONCLUSIONS: This study shows a wide distribution of the RI normal values in the pig model, and our results do not support the normal ranges for RI and RIR, or the cut-off values used in clinical practice. 相似文献
25.
Acute otomastoiditis and its complications: role of CT 总被引:2,自引:0,他引:2
Acute bacterial (suppurative) otomastoiditis responds to antibiotic treatment; radiologic study is required only when there is clinical suggestion of coalescent mastoiditis, intracranial complications, or an underlying chronic disease. Computed tomography (CT) is the method of choice for evaluating otogenic intra- or extra-cranial complications. CT scans can show stages of disease progression when infection has spread by way of soft tissue, blood, and bone pathways into the dural venous sinuses, meninges, labyrinth, facial nerves, epidural and other intracranial spaces. When there is clinical suggestion of acute coalescent mastoiditis, a CT scan of the temporal bone can confirm the presence of rarefying osteitis, coalescence of the air cells, and subperiosteal abscess. 相似文献
26.
Preoperative radiotherapy for rectal cancer: implications for surgeons, pathologists and radiologists 总被引:9,自引:0,他引:9
BACKGROUND: Over 10,000 new cases of rectal cancer are reported in the UK each year and adjuvant treatments, such as preoperative radiotherapy, are now being used almost routinely. METHODS: A literature review was performed on the Medline database for English language publications on preoperative radiotherapy and rectal cancer. The radioresponsiveness of rectal cancer, tumour downstaging, radiological staging of irradiated rectal cancer, effects of radiotherapy on anastomotic integrity, anorectal and genitourinary function, the role of preoperative radiotherapy in local excision of rectal cancer, and the histological changes peculiar to radiotherapy were evaluated. Results and conclusion: Following preoperative radiotherapy, rectal cancer may be downstaged or, occasionally, eradicated histologically. Rectal cancer can now be staged accurately before operation, but this is significantly less reliable following irradiation. The pathological specimen must be examined thoroughly before a tumour can be reported to have been eradicated, especially as unique histological changes are produced by radiotherapy. There is no evidence to suggest that preoperative radiotherapy adversely affects anastomotic integrity. It appears that preoperative radiotherapy has some adverse affects on long-term anorectal dysfunction, but this must not distract from its main objectives in rectal cancer, namely reduced local recurrence rates and improved overall survival. 相似文献
27.
28.
Hyperbaric oxygen therapy is a treatment with a number of different indications. It is managed by different specialities, but most of the hyperbaric facilities are driven by departments of anaesthesiology, and some of the patients are critically ill. This paper deals briefly with modes of administration, mechanisms of action, indications and risks. Two indications, carbon monoxide poisoning and necrotising soft tissue infections, are of special interest for the anaesthesiologist, and are therefore dealt with in little more detail. 相似文献
29.
Guangfu Jia Michelle Kwon Huan Ling Liang Jordan Mortensen Vani Nilakantan William E. Sweeney Frank Park 《Pediatric nephrology (Berlin, Germany)》2010,25(6):1139-1146
Angiotensin converting enzyme (ACE) inhibition is a common therapeutic modality in the treatment of autosomal recessive polycystic
kidney disease (ARPKD). This study was designed to investigate whether chronic inhibition of ACE would have a therapeutic
effect in attenuating the progression of renal cystogenesis in an orthologous rat model of ARPKD, the polycystic kidney (PCK)
rat. Lisinopril (3 mg/kg per day) was administered orally for a period of 12 weeks, beginning at post-natal week 4. Lisinopril
treatment resulted in an ∼30% improvement in the collecting duct cystic indices (CT CI) of PCK animals. Activation of extracellular
signal-regulated kinase 1 (ERK1) and 2 (ERK2), proliferative signaling markers, and proliferating cell nuclear antigen (PCNA),
an end-point marker for proliferation, was reduced following chronic treatment with lisinopril compared to that in vehicle-treated
PCK rats. To assess whether apoptotic pathways were altered due to chronic ACE inhibition, we examined p38 mitogen activated
protein kinase (MAPK) and stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK), which are markers of apoptotic
signaling cascades. p38 MAPK was significantly reduced (P < 0.0001) following chronic treatment with lisinopril, but no change in the activation of SAPK/JNK could be detected by immunoblot
analysis. Lisinopril treatment resulted in a significant reduction (P < 0.01) in cleaved caspase-7 levels, but not caspase-3 activity, in PCK rat kidneys compared to the vehicle-treated PCK rat
kidneys. Proteinuria was completely ameliorated in the presence of chronic ACE inhibition in the lisinopril-treated rats compared
with the vehicle-treated PCK rats. In all, these findings demonstrated that chronic ACE inhibition can beneficially alter
proliferative and apoptotic pathways to promote therapeutic reductions in renal cyst development in ARPKD. 相似文献
30.
Sergej Zogovic Morten Gaarden Frank Viborg Mortensen 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2015,19(3)