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1.
Intracranial circulation: pulse-sequence considerations in three- dimensional (volume) MR angiography 总被引:2,自引:0,他引:2
The technique and feasibility of magnetic resonance (MR) angiography of intracranial vessels were studied in 35 healthy volunteers. Variations in image orientation, repetition time (TR), and flip angle were evaluated to determine their effects on flow-related enhancement. Gradient modifications--including echo time (TE), motion compensation, bandwidth, and field of view--were also studied in an effort to reduce motion-induced phase shifts. Results indicated that a FISP (fast imaging with steady precession) sequence with a TR of 50 msec, TE of 15 msec, velocity compensation in the read and section-select directions, acceleration compensation in the read direction, anisotropic volume, and a 1.25-mm partition thickness produced three-dimensional angiographic MR images that were accurate and reproducible in the depiction of the major intracranial vessels. Difficulties with field of view, persistent signal void secondary to higher-order motion, and spatial resolution remain major problems requiring additional study. 相似文献
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The management of symptoms in advanced cancer: experience in a hospital-based continuing care unit. 下载免费PDF全文
The treatment received by 158 patients with advanced cancer admitted over one year to the Continuing Care Unit at the Royal Marsden Hospital has been reviewed. The unit is an integral part of the hospital and this is reflected in the fact that 46 patients (29%) received radiotherapy, hormone therapy, chemotherapy or surgery in addition to symptomatic treatment for palliation of troublesome symptoms. One hundred and thirty-one patients received oral morphine in doses ranging from 2.5 mg 4-hourly to 700 mg 4-hourly. Patients with renal or hepatic impairment required lower doses of morphine and there was a highly significant inverse relationship between morphine dose and age. Eighty-five patients (54%) received parenteral diamorphine at some time due to their inability to take oral morphine. One hundred and twenty-three patients (78%) received a co-analgesic drug and anti-emetics were required by 78 patients (49% overall; 56% of those receiving morphine). Transcutaneous electrical nerve stimulation, acupuncture and relaxation were employed in selected patients, and graduated compression sleeves were used to treat lymphoedema. These data highlight the wide range of therapeutic options available to control the symptoms of advanced cancer and also indicate that tumoricidal treatments used in conjunction with symptomatic treatments may have a significant part to play. 相似文献
3.
Paediatric dacryocystorhinostomy 总被引:1,自引:0,他引:1
KN Hakin FRCS FRCOphth TJ Sullivan FRACO FRACS A Sharma FCOphth † RAN Welham FRCS FCOphth † 《Clinical & experimental ophthalmology》1994,22(4):231-235
Of 258 cases of dacryocystorhinostomy performed on children in the period September 1981 to September 1991, 130 were for simple, unresolved congenital nasolacrimal duct obstruction. Other indications for surgery included punctal agenesis, lacrimal fistula, post-traumatic and post-inflammatory canalicular obstruction. Of 177 children without canalicular pathology, 171 (96%) were relieved of symptoms with one operation, without canalicular intubation. Of 81 cases with canalicular disease, 55 of 70 (79%) who underwent DCR plus canalicular intubation, and 10 of 11 who underwent DCR plus Lester-Jones tube, were substantially improved with one operation. No child required peroperative or postoperative blood transfusion. Dacryocystorhinostomy in childhood, in experienced surgical hands, is a safe procedure, achieving relief of symptoms in most cases, particularly in the absence of canalicular disease. 相似文献
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EFNS Guidelines on diagnosis and treatment of brain metastases: report of an EFNS Task Force 总被引:2,自引:0,他引:2
R. Soffietti P. Cornu J. Y. Delattre R. Grant F. Graus W. Grisold J. Heimans J. Hildebrand P. Hoskin M. Kalljo P. Krauseneck C. Marosi T. Siegal C. Vecht 《European journal of neurology》2006,13(7):674-681
The objectives have been to establish evidence-based guidelines and identify controversies regarding the management of patients with brain metastases. The collection of scientific data was obtained by consulting the Cochrane Library, bibliographic databases, overview papers and previous guidelines from scientific societies and organizations. A tissue diagnosis is necessary when the primary tumor is unknown or the aspect on computed tomography/magnetic resonance imaging is atypical. Dexamethasone is the corticosteroid of choice for cerebral edema. Anticonvulsants should not be prescribed prophylactically. Surgery should be considered in patients with up to three brain metastases, being effective in prolonging survival when the systemic disease is absent/controlled and the performance status is high. Stereotactic radiosurgery should be considered in patients with metastases of 3–3.5 cm of maximum diameter. Whole-brain radiotherapy (WBRT) after surgery or radiosurgery is debated: in case of absent/controlled systemic cancer and Karnofsky Performance score of 70 or more, one can either withhold initial WBRT or deliver early WBRT with conventional fractionation to avoid late neurotoxicity. WBRT alone is the treatment of choice for patients with single or multiple brain metastases not amenable to surgery or radiosurgery. Chemotherapy may be the initial treatment for patients with brain metastases from chemosensitive tumors. 相似文献
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Factors influencing women to undergo screening mammography 总被引:2,自引:0,他引:2
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Inhibition by sumatriptan of central trigeminal neurones only after blood-brain barrier disruption. 总被引:2,自引:1,他引:1 下载免费PDF全文
1. The 5-hydroxytryptamine (5-HT1)-like agonist, sumatriptan, is highly efficient in the relief of migraine headache and its accompanying symptoms. 2. Experimental evidence has indicated that its site of action may be on the cranial vessels or on the trigeminal innervation of the cranium, or both, since sumatriptan does not pass the blood-brain barrier easily under normal circumstances. It is, however, not clear whether the blood-brain barrier is normal or abnormal during a migraine attack. 3. In this study, single unit activity and trigeminal somatosensory evoked potentials in central trigeminal neurones were monitored during electrical stimulation of the superior sagittal sinus. 4. Intravenous administration of sumatriptan (100 micrograms kg-1) did not alter trigeminal evoked activity unless the permeability of the blood-brain barrier had been increased by infusion of an hyperosmolar mannitol solution. After blood-brain barrier disruption, sumatriptan decreased the peak-to-peak amplitude of evoked potentials by 40 +/- 6% and the probability of firing of single units by 30 +/- 9%. Mannitol infusions alone in control animals caused no changes in evoked potentials or single unit activity. 5. The data suggest that in normal circumstances sumatriptan does not have sufficient access to trigeminal neurons to alter their function. 相似文献