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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
2.
3.
Maxillary sinusitis in adults: an evaluation of placebo-controlled double-blind trials 总被引:1,自引:0,他引:1
BACKGROUND: In general practice, acute sinusitis is frequently diagnosed
and treated with antibiotics. OBJECTIVE: This study aimed to determine the
evidence for the effectiveness of antibiotic treatment in acute maxillary
sinusitis in adults by assessing the methodological quality of
placebo-controlled double-blind randomized trials. METHOD: An evaluation by
four raters through a 35-item scoring-scale for internal and external
validity of all placebo-controlled double-blind randomized trials on acute
sinusitis found between January 1966 and July 1996. RESULTS: Eighty-five
trials were excluded because they were not placebo-controlled,
double-blind, randomized, or were carried out in patients with chronic
sinusitis or in children. The three remaining trials were performed in
different populations (one in general practice) between 1973 and 1978. Only
one study claimed superiority of antibiotic treatment. Different inclusion
criteria and major outcome measures were used by the authors. The
reliability of major outcome events was reported poorly or not at all and
in two studies outcome measures were clinically inappropriate. The studies
scored 30-62% of the maximum attainable score for internal validity and
10-20% for external validity. CONCLUSION: The effectiveness of antibiotic
treatment in acute maxillary sinusitis in a general practice population is
not based sufficiently on evidence.
相似文献
4.
5.
G Nanni MD G Balduzzi MD R Capoluongo MD A Scotti MD G Rosso MD C Botta MD P Demichelis MD M Daffara MD E Coppo MD 《Obesity surgery》1997,7(1):26-29
Background: Biliopancreatic diversion (BPD), by ad hoc stomach resection (AHS-BPD) has been accepted as an effective surgical treatment for morbid obesity. Methods: Between 1.1.1992
and 31.7.1996, 59 patients (54 females, five males, mean age 40.3 years, range 23-61 years) underwent AHS-BPD. Mean preoperative
body-weight was 121.2 kg (range 94-160), with a mean body mass index of 48.6 (range 35-64). Three of these patients were converted
from a previous vertical banded gastroplasty to AHS-BPD (one patient with stomach preservation). After at least 36 months
follow-up, seven patients underwent abdominal dermolipectomy (five with associated incisional hernia repair, one with thigh
dermolipectomy). Results: Mean post-operative hospital stay was 13 days (range 10-30 days). Follow-up is currently in progress
in all patients. Excess body weight-loss was 78% in 33 patients with 24 months follow-up, with excellent long-term weight
loss maintenance. Protein deficiency was the main specific complication, encountered in two patients (3.4%). Mortality was
one patient (1.7%), due to pulmonary embolus. Conclusions: This clinical experience supports the effectiveness and safety
of AHS-BPD, despite some criticism. This procedure appears to be suitable for patients with clinically severe obesity who
will poorly tolerate food intake restriction but will accept long-term follow-up. Careful preoperative clinical assessment
and selection of patients who will be reliable in long-term follow-up are the keys to success with AHS-BPD, both in terms
of weight loss and reduction of specific metabolic complications. 相似文献
6.
H Angus-Leppan GA Lambert J Michalicek 《Cephalalgia : an international journal of headache》1997,17(6):625-630
Co-existence of facial and occipital pain may occur in occipital neuralgia, migraine and cluster headache; suggesting convergence of trigeminal and cervical afferents. Such convergence has been shown in humans and other animals, but the site and extent of this are uncertain. In anaesthetized adult cats, the superior sagittal sinus and occipital nerve were stimulated electrically, and extracellular recordings made in the dorsolateral area of the upper cervical cord using glass-coated tungsten electrodes. Of 49 units in 10 cats, 33 (67%) had input from the superior sagittal sinus and the occipital nerve. Thirteen (27%) had superior sagittal sinus input and 3 (6%) had occipital nerve input. Convergent receptive fields were identified mechanically in 7 units. These experiments in cats show convergent input from occipital nerve and superior sagittal sinus on dorsolateral area units in two-thirds of cases studied. This experimental site of trigeminocervical convergence may relate to referral of pain in occipital neuralgia and other headaches. 相似文献
7.
In patients with PG-dependent renal function, NSAID administration
constantly reduces GFR and RBF in a dose-dependent fashion. In this
situation, the risk of overt acute renal failure is high and should be
taken into proper account. In contrast, the incidence of NSAID-related
renal structural alterations appears to be very low, yet the absolute
number of patients may be significant considering the wide use of such
drugs. Concerning the antiproteinuric effect of NSAIDs, the unfavourable
ratio risk/benefit does not seem to support their indication in proteinuric
nephropathies. The development of PGHS-2 selective inhibitors is promising,
and may open new therapeutical strategies in the treatment of the
progression of renal disease.
相似文献
8.
9.
Pleural malignant mesothelioma and non-occupational exposure to asbestos in Casale Monferrato, Italy. 总被引:6,自引:3,他引:3
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C Magnani B Terracini C Ivaldi M Botta A Mancini A Andrion 《Occupational and environmental medicine》1995,52(6):362-367
OBJECTIVES--To assess and quantify the occurrence of pleural malignant mesotheliomas in people who neither experienced occupational exposure to asbestos nor were married to (or known to live with) workers exposed to asbestos in the workplace. The study was conducted in the area of the local health authority of Casale Monferrato, in north western Italy, where a large factory that produced asbestos cement was active up to 1985. No other major activities related to asbestos have ever been present in the area. METHODS--A retrospective survey covering the period 1980 to 1991 identified 126 incident pleural malignant mesotheliomas histologically diagnosed among residents in the local health authority (population at the 1981 census 98,000). Submission of 83 of 95 cases diagnosed during 1980-9 for revision by a panel of five expert pathologists led to the exclusion of 21. The 31 cases diagnosed in 1990-1 were not submitted for revision. For 64 of the 105 retained cases, information derived from different sources (rosters of the employees in the asbestos cement factory dated back to 1907, list of their spouses, clinical records) did not suggest occupational or paraoccupational exposure to asbestos. RESULTS--Incidence excludes cases for which there was some suggestion of occupational or paraoccupational exposure to asbestos. Incidence of histologically confirmed malignant mesothelioma among residents in the local health authority (annual x 100,000; age adjusted) was 4.2 in men and 2.3 in women (based on 26 and 18 cases respectively). In both sexes, rates in 1985-9 were higher than in the previous quinquennium. Corresponding estimates for 1990-1 (based on unrevised diagnoses) suggest similar rates in men and women. CONCLUSION--Rate ratios which are four to six times those measured by conventional Italian cancer registries can hardly be totally explained by bias produced by lack of recognition of occupational or paraoccupational exposure. The problem of proving this type of negative data is common to other circumstances of alleged cancer clusters of environmental (non occupational) origin. 相似文献
10.
Emanuele Pilato Andrea Dell'Amore Luca Botta Giorgio Arpesella 《European journal of cardio-thoracic surgery》2007,32(1):180-182
Familial amyloidotic polyneuropathy (FAP) is an inherited disease characterized by an abnormal systemic deposition of a mutant protein called transthyretin (TTR) with elective involvement of the peripheral nervous system, but often determining cardiac, gastrointestinal, and urinary tract dysfunction. FAP commonly affects the liver and the heart until end-organs failure. Transthyretin amyloidosis is today an accepted indication for orthotopic liver transplantation (OLT). Combined heart and liver transplantation (CHLT) may be an attractive and rational treatment option when both organs are contemporary involved by this type of amyloidotic disease. Nowadays, surgical indications and techniques are far from being consolidated because only few cases of CHLT have been previously reported in literature. From November 1999 to May 2006, we performed five orthotopic combined heart and liver transplantations for FAP at our institution. Our surgical experience and clinical outcomes are herein reported. 相似文献