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131.
La Seta F Buccellato A Albanese M Barbiera F Cottone M Oliva L Agricola A Costanzo GS Lagalla R 《La Radiologia medica》2004,108(5-6):515-521
PURPOSE: To evaluate the current role of small bowel (SB) radiologic barium examinations in adult celiac disease (ACD). MATERIALS AND METHODS: Retrospective review of 61 SB barium examinations in 280 ACD patients. Sixty-one examinations in 61 patients were performed: 7/61 with small bowel 'follow-through' (SBFT) method, and 54/61 with small bowel double-contrast enteroclysis (SBE). Radiological criteria for ACD diagnosis were divided in four groups: 1) definite ACD (reversal of jejuno-ileal fold pattern); 2) possible ACD (malabsorption pattern and ileal jejunization); 3) malabsorption (fluid, dilatation, 'moulage', flocculation); 4) complicated ACD (irregular, thickened, nodular folds; wall thickening; masses). RESULTS: In 49/61 patients RX examinations were performed before ACD diagnosis. In this group, clinical presentations included one or more of the following: diarrhea, weight loss, malabsorption, anemia, abdominal pain; 7/49 had a SBFT, and 42/49 a SBE. All 7 SBFTs showed pattern 3, and 8/42 SBEs showed pattern 2 (suspected ACD). In 34/42 patients SBE allowed a definite ACD diagnosis (pattern 1); however, 6/34 were also false-positive for complicated ACD (pattern 4). Ten out of sixty-one patients were clinically suspected of having complicated ACD, correctly excluded (8/8) or confirmed (2/2) by SBE. None of these 59/61 patients had a radiologic diagnosis of normal' SB. The last 2/61 patients with ACD, examined for persisting chronic anemia, had a normal SBE. CONCLUSIONS: This study confirm that SB radiology may be of value either in ACD diagnosis or in excluding complications: SBE is currently the most accurate examination. SBE alone is however less accurate in confirming complicated ACD; further imaging techniques are always needed in this clinical context. 相似文献
132.
Scioscia M Vimercati A Doria G Cuccovillo A Lezzi V Lacerenza A Piro V Greco P 《Minerva ginecologica》2003,55(4):347-351
AIM: Prostaglandin analogues provide an effective method for induction of abortion in the second trimester of pregnancy. The clinical outcome and the risk of complications were evaluated in a group of women having a medical termination of pregnancy with gemeprost. METHODS: Three-hundred and six women undergoing second trimester termination of pregnancy, between January 1998 and July 2002 in our center, were studied. All women were given 1 mg vaginal gemeprost every 3 h up to a maximum of 3 doses in the first 24 hours. If the abortion did not occur within the first 24 hours after initiation of treatment, they were given a 2(nd) course of gemeprost. Outcome measures included failure of the 1st course of gemeprost, length of hospital stay after expulsion of conceptus, heavy blood loss with or without necessity of uterine packing or blood transfusion, and failure of induction. RESULTS: There was a significant difference, with better results in women with previous deliveries (vaginal or abdominal), as to the failure to abort after the 1(st) course of PG (P<0.01). Length of hospital stay, complications and failure of induction were independent from parity. Twelve (3.9%) women failed to abort with gemeprost and required other methods for abortion. CONCLUSIONS: The study confirms the efficacy of gemeprost for mid-trimester termination of pregnancy, although it is a risky and costly procedure, requiring hospitalisation and is associated with higher complication rate than the first trimester surgical abortion. 相似文献
133.
Lafortuna CL Jahoda M Azzellino A Saibene F Colombini A 《European journal of applied physiology》2003,90(3-4):387-395
Twenty-four Mediterranean fin whales were tracked in open sea with a method based on the assessment of the animal differential position in respect of the observer's absolute position aboard a vessel, with the concomitant recording of the respiratory activity. Short distance video recording was also performed in two whales, permitting the simultaneous determination of single breath expiratory (TE) and inspiratory (TI) durations. In the 24 whales swimming at an average velocity of 1.39 (0.47) m·s–1 [mean (SD), range: 0.62–2.44 m·s–1], 2068 breaths organized in 477 respiratory cycles were observed. Each cycle entailed a prolonged apnoea dive phase [225 (91) s, Tdive) followed by a period near the surface [62 (28) s, surfacing], during which a series of breaths [4.6 (1.8)] was performed at short intervals. On the basis of track length and swimming velocity, two groups of animals were devised differing for convolution of the course (p<0.001), extension of ranging territory (p<0.01) and horizontal swimming velocity (p<0.05), which may represent two distinct behaviours. A possibly general mechanism of control of breathing in cetaceans was found, consistent with a model of constant tidal volume and variable respiratory frequency. Coherently with this model,
TE was independent of TI or Tdive, in line with a passive expiration, while
TI appeared to be negatively correlated with
Tdive (p<0.05), otherwise suggesting, similarly with terrestrial mammals, a significant role of hypercapnic stimulation. The estimated O2
consumption of about 150 l·min–1 is in line with the general allometric regression for mammals and corresponds to an energetic expenditure of 85–95 kJ·kg–1·day–1.Partially presented as a poster at The World Marine Mammal Science Conference and 12th Annual Conference of the European Cetacean Society, Monaco (Montecarlo), 20–24 January 1998.Angelo Colombini provided technical assistance. 相似文献
134.
Manfredi M McCullough MJ Al-Karaawi ZM Hurel SJ Porter SR 《Oral microbiology and immunology》2002,17(3):181-185
Previous studies have shown a high incidence (77%) of isolation of Candida spp. from the oral cavities of patients with type 1 diabetes mellitus. The aim of the present study was to assess the prevalence of yeast in the oral cavities of patients suffering from type 1 and type 2 diabetes mellitus. The patients were classified according to the level of diabetic control (HbA1c), and further stratified on the presence or absence of dental prosthesis. Oral rinse samples were assessed for the growth of yeast and the degree of colonization. Oral isolates were defined to the species level by both phenotypic and novel molecular methods. The overall proportion (60%) of diabetic patients who had Candida spp. isolated from the oral cavity was similar to that previously reported. Local oral factors, such as the presence of dentures, seemed to have a greater influence than diabetic status on the amount and species of Candida isolated from the oral cavities of diabetic patients. Diabetic patients with dentures had more non-albicans Candida isolated from their mouths than dentate diabetic patients. Candida dubliniensis was isolated from diabetic patients and may have a predilection for dentate patients. 相似文献
135.
Feliciotti F Paganini AM Guerrieri M Baldarelli M De Sanctis A Campagnacci R Lezoche E 《Surgical laparoscopy, endoscopy & percutaneous techniques》2003,13(5):328-333
Aim of this study was to evaluate the results in 6 patients undergoing laparoscopic adrenalectomy for the treatment of solitary adrenal gland metastases. One hundred forty-five patients underwent laparoscopic adrenalectomy by transperitoneal anterior approach. In 6 patients the indication was the presence of a solitary adrenal gland metastasis. Primary tumors were the following: truncal melanoma, gastric cancer, renal cancer, lung cancer, and breast cancer. Mean age was 57 years (range 44-70 years). Three patients underwent right adrenalectomy and 3 patients a left adrenalectomy. No conversion to open surgery occurred. No mortality or intraoperative complications were observed. Mean operative time was 103 minutes (range 70-150) for right adrenalectomy and 170 minutes (range 90-280) for left adrenalectomy. No postoperative complications occurred. Mean diameter of the tumor was 3.5 cm (range 2-5 cm). Tumor free margins were obtained in every case. Mean hospital stay was 2 days (range 2-3 days). At follow-up, 2 patients have died of systemic dissemination of the disease, one 15 months and one 24 months after the operation. The remaining 4 patients are alive and disease free at a mean follow-up of 7 months (range 4-11 months). So far, no port site metastases or local recurrence have been observed. In our experience adrenal gland metastasis can be treated safely and effectively by the laparoscopic transperitoneal anterior approach. 相似文献
136.
Avolio C Ruggieri M Giuliani F Liuzzi GM Leante R Riccio P Livrea P Trojano M 《Journal of neuroimmunology》2003,136(1-2):46-53
In multiple sclerosis (MS), matrix metalloproteinase (MMP) activity in tissues is the result of a balance between MMPs and their tissue inhibitors (TIMPs). MMP-9 predominates in acute MS lesions and is inhibited by TIMP-1, while MMP-2 may participate in the remodeling of the extracellular matrix (ECM) such as in chronic disease and is inhibited by TIMP-2. These differences may be reflected in serum and cerebrospinal fluid (CSF). We have tried to characterize MMP-2 and MMP-9 activities, in relation to their respective TIMPs, 2 and 1, as a factor of different types of the disease, as this information was not previously clearly stated. We found the MMP-2/TIMP-2 ratio in serum to show higher values in secondary progressive (SP, p=0.02) and primary progressive (PP, p=0.01) MS than short disease duration (SDD) relapsing-remitting (RR) MS, but not different from the healthy control (HC) group. Whereas the MMP-9/TIMP-1 ratio in serum showed higher (p=0.04) values in SDD RR MS than PP but also in active patients, evaluated either clinically (p=0.006) or from the magnetic resonance imaging (MRI, p<0.05), compared to inactive disease. CSF MMP to TIMP ratios did not differ between MS subtypes, suggesting systemic rather CNS-restricted changes. These results show that an increase in MMP-2/TIMP-2 ratio marks chronic progression in MS, but it is as high as in HC, and also confirm that high MMP-9 activity characterizes short duration relapsing and active forms of the disease. 相似文献
137.
138.
In Germany the dD by Feldmann is a frequently used test in child assessment. Unknown, however, is the validity of the dD in the assessment of children with specific developmental language disorders. The dD by Feldmann are pairs of three-syllable content words which are presented dichotically. In this controlled cross-sectional study 65 children took the dichotic listening test by Feldmann (dD). The experimental group comprised 34 children with developmental reading and spelling disorders. The control group comprised 31 children with normal reading and spelling development. Age and nonverbal IQ were matched in both groups. The mean age was 9.8 years (range 7 - 11 years). The dichotic listening performance of right and left ear was registered separately. Twenty word pairs were presented dichotically at a constant amplitude of 65 dB. Memorisation of word pairs was tested under free recall conditions. A score of 100 % can be attained, if all word pairs are repeated correctly. Results demonstrated that no child attained a score of 100 %. As expected, the children with the developmental reading and spelling disorders attained significantly lower scores than the children in the control group (42.4 % versus 64 %). The reason for the lower results in the experimental group was left ear dichotic listening performance. There were no significant differences in right dichotic listening performance. Raw score overlaps occurred to some extent in both groups, but scores of 30 % or less were only observed in the experimental group. Scores correlated significantly with age, but not with nonverbal IQ. However, dD performance significantly correlated with several measures of phonological and syntactic language development as well as with auditory working memory. Based on these results it is our opinion that performance scores of the dD by Feldmann should be interpreted cautiously until validation studies have been carried out. 相似文献
139.
Cartwright JH González DL Piro O 《Proceedings of the National Academy of Sciences of the United States of America》2001,98(9):4855-4859
Two and a half millennia ago Pythagoras initiated the scientific
study of the pitch of sounds; yet our understanding of the mechanisms
of pitch perception remains incomplete. Physical models of pitch
perception try to explain from elementary principles why certain
physical characteristics of the stimulus lead to particular pitch
sensations. There are two broad categories of pitch-perception models:
place or spectral models consider that pitch is mainly related to the
Fourier spectrum of the stimulus, whereas for periodicity or temporal
models its characteristics in the time domain are more important.
Current models from either class are usually computationally intensive,
implementing a series of steps more or less supported by auditory
physiology. However, the brain has to analyze and react in real time to
an enormous amount of information from the ear and other senses. How is
all this information efficiently represented and processed in the
nervous system? A proposal of nonlinear and complex systems research is
that dynamical attractors may form the basis of neural information
processing. Because the auditory system is a complex and highly
nonlinear dynamical system, it is natural to suppose that dynamical
attractors may carry perceptual and functional meaning. Here we show
that this idea, scarcely developed in current pitch models, can be
successfully applied to pitch perception.The pitch of a sound is
where we perceive it to lie on a musical scale. For a pure tone with a
single frequency component, pitch rises monotonically with frequency.
However, more complex signals also elicit a pitch sensation. Some
instances are presented in Fig. Fig.1.1. These
are sounds produced by the nonlinear interaction of two or more
periodic sources, by amplitude or frequency modulation. All such
stimuli, which may be termed complex tones, produce a definite pitch
sensation, and all of them exhibit a certain spectral periodicity. Many
natural sounds have this quality, including vowel sounds in human
speech and vocalizations of many other animals. Evidence for the
importance of spectral periodicity in sound processing by humans is
that noisy stimuli exhibiting this property also elicit a pitch
sensation. An example is repetition pitch: the pitch of ripple noise
(1), which arises naturally when the sound from a noisy source
interacts with a delayed version of itself, produced, for example, by a
single or multiple echo. It is clear that an efficient mechanism for
the analysis and recognition of complex tones represents an
evolutionary advantage for an organism. In this light, the pitch
percept may be seen as an effective one-parameter categorization of
sounds possessing some spectral periodicity (2–5).
Figure 1Stimuli: waveforms, Fourier spectra, and pitches. (a) A
1-kHz pure tone; the pitch coincides with the frequency
ω0. (b) Complex tone formed by 200-Hz
fundamental plus overtones; the pitch is at the frequency of the
fundamental ω0. ... 相似文献
140.