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排序方式: 共有970条查询结果,搜索用时 31 毫秒
81.
Yasmine Neirijnck Antoine Reginensi Kirsten Y. Renkema Filippo Massa Vladimir M. Kozlov Haroun Dhib Ernie M.H.F. Bongers Wout F. Feitz Albertien M. van Eerde Veronique Lefebvre Nine V.A.M. Knoers Mansoureh Tabatabaei Herbert Schulz Helen McNeill Franz Schaefer Michael Wegner Elisabeth Sock Andreas Schedl 《Kidney international》2018,93(5):1142-1153
82.
I Thaler D Manor S Rottem I E Timor-Tritsch J M Brandes J Itskovitz 《Journal of clinical ultrasound : JCU》1990,18(4):364-369
Perfusion characteristics of the female pelvic vessels were studied by a high-frequency transvaginal image-directed Doppler system. A 5-MHz Doppler transducer was coupled to a 6.5-MHz probe especially designed for intravaginal use. Distinct patterns of flow velocity waveforms were obtained from the ascending branch of the uterine artery, before and during pregnancy. A gradual increase in diastolic flow throughout gestation was observed, consistent with a decrease in vessel resistance. Flow velocity profiles in the ovarian artery were sampled from the infundibulo-pelvic ligament. Only limited diastolic flow could be detected in either ovary during the follicular phase of the cycle. In the luteal phase there was a marked increase in this flow but only in the ovary containing the corpus luteum. In early pregnancy the high diastolic flow was maintained or even increased, consistent with a low arterial resistance. High image resolution and a higher frequency Doppler transducer increase the usefulness of this technique in the hemodynamic evaluation of the female pelvic vessels. 相似文献
83.
The influence of ageing on the sympathetic nervous system and adrenal medulla was studied neuro chemically in humans, using
isotopic dilution measurement of regional and whole body catecholamine release to plasma in humans. With ageing, sympathetic
activation was evident in the heart, and the gut and liver at rest. The mechanism appeared to be by activation of sympathoexcitatory
noradrenergic suprabulbar projections from the brainstem. Sympathetic nervous responses with stressors were augmented. Conversely,
adrenal medullary release of epinephrine was subnormal in the elderly, at rest and during stress.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
84.
85.
Syed Adibul Hasan Rizvi Syed Ali Anwar Naqvi Mirza Naqi Zafar Farida Mazhar Rana Muzaffar Rubina Naqvi Fazal Akhtar Ejaz Ahmed 《Transplant international》2009,22(6):615-621
Donor shortage and absence of transplant law lead to unrelated commercial transplants in Pakistan. We report the socio‐economic and outcome parameters of 126 local recipients of unrelated kidney vendor transplants presenting to our institute between 1997 and 2007. Their outcome was compared with 180 recipients of living‐related donor transplants matched for age, gender and transplant duration as controls. Age of commercial recipients was 35.63 ± 11.57 years with an M:F ratio of 2.4:1. Majority (92%) were transplanted in northern Pakistan paying US$7271 ± 2198. All were educated with 50% being graduates or above and rich earning a monthly salary of US$517 ± 518 with 44% earning >US$500. Comparison of commercial recipients with controls showed high comorbidities 35 (28%) vs. 14 (8%) (P = 0.0001) with diabetes, hepatitis‐C and cardiovascular diseases. Donor age was 29.97 ± 6.16 vs. 32.63 ± 9.3 years (P = 0.035). Biologic agents induction in 101 (80%) vs. 14 (8%) (P = 0.0001), acute rejections in 42 (33%) vs. 31 (17%) (P = 0.005), 1‐year creatinine 1.84 ± 1.28 vs. 1.27 ± 0.4 mg/dl (P = 0.0001), surgical complications 28 (22%) vs. 14 (8%) (P = 0.001), tuberculosis 14 (11%) vs. 6 (6%) (P = 0.007), acute hepatitis 20 (16%) vs. 3 (2%) (P = 0.0001), cytomegalovirus 33 (26%) vs. 21 (11%) (P = 0.001) and recurrent urinary tract infection 35 (28%) vs. 30 (16%) (P = 0.034). Overall 1‐ and 5‐year graft survival was 86% and 45% vs. 94% and 80%, respectively (P = 0.00001). Total deaths were 34 (27%) vs. 12 (6.0%) (P = 0.001). In conclusion, recipients of the vended kidneys are poor candidates, educated, rich and often self‐selecting. Their outcome is poor, which will leave them poorer still and back to dialysis if not death. 相似文献
86.
Annemarie M. M. Vlaar Angela Bouwmans Werner H. Mess Selma C. Tromp Wim E. J. Weber 《Journal of neurology》2009,256(4):530-538
Background
Transcranial duplex scanning (TCD) of the substantia nigra (SN) is increasingly used to diagnose Idiopathic Parkinson’s Disease
(IPD). Up until now 70 diagnostic studies have been published, not only on investigation of the SN, but also of the lenticular
nucleus (LN) and the Raphe nuclei (RN).
Method
We systematically reviewed all diagnostic TCD studies in parkinsonian patients up to June 2008.
Results
We found 35 eligible studies. Of the 1534 IPD patients investigated in the 35 studies 200 (13 %) had an inconclusive SN-TCD.
An increased echo-intensity of the SN was seen in 1167 (87 %) of the 1334 IPD patients, 276 (12 %) of the 2340 healthy controls
and in 41 (30 %) of the 138 patients with an atypical parkinsonian syndrome (APS). On the contrary, a pathological LNTCD was
found more often in APS patients (79 %) than in IPD patients (23 %) and healthy controls (6 %). A decreased echo-intensity
of the RN was found more often in depressed (46 %) than in non-depressed IPD patients (16 %).
Conclusions
SN-TCD accurately differentiates between patients with IPD and healthy controls, but not between patients with IPD and APS.
LN-TCD is only moderate accurate to delineate IPD from APS, but combinations of SN- and LN-TCD may be more promising. RN-TCD
has only marginal diagnostic accuracy in diagnosing depression in IPD and non-IPD patients. Before TCD can be implicated,
more research is needed to standardize the TCD technique, to investigate the TCD in non-research settings and to determine
the additional value of TCD compared with currently used clinical techniques like SPECT imaging. 相似文献
87.
88.
Jung EM Kubale R Ritter G Gallegos MT Jungius KP Rupp N Clevert DA 《European radiology》2007,17(2):439-447
The purpose was to evaluate whether B-flow can improve the ultrasonographic diagnosis of preocclusive stenosis and occlusion
of the internal carotid artery (ICA) compared with colour-coded Doppler and power Doppler. Ninety patients with occlusions
or preocclusive stenoses of the ICA suspected by Doppler sonography were examined with B-flow in comparison with colour-coded
Doppler sonography (CCDS), power Doppler (PD) and intra-arterial digital subtraction angiography (DSA). Intrastenotic flow
detection and lengths of stenoses were the main criteria. Ulcerated plaques found by surgery in 42/90 patients were compared
by ultrasonography (US). Diagnosis of ICA occlusion with CCDS, PD and B-flow was correct in all 42 cases. A preocclusive ICA
stenosis in DSA was detected correctly in all 48/48 cases (100%) for B-flow, in 44/48 (92%) for PD and in 39/48 (81%) for
CCDS. Surgical findings showed in 17/42 cases ulcerated plaques; 15/17 (89%) of these cases were detected with B-flow, 12/17
(71%) with PD, 10/17 (59%) with CCDS, and 8/17 (47%) with DSA. With B-flow the extent of stenosis was appraised more precisely
than with PD and CCDS (P<0.0001). In conclusion, B-flow is a reliable method for preocclusive stenosis of the ICA with less intrastenotic flow artefacts.
B-flow facilitates the characterization of plaque morphologies. 相似文献
89.
Sei Saitoh Nobuo Terada Nobuhiko Ohno Yurika Saitoh Manoocher Soleimani Shinichi Ohno 《Medical molecular morphology》2009,42(1):24-31
Protein kinases (PKs) phosphorylate proteins at active regions for signal transduction. In this study, normal and hypoxic
mouse kidneys were prepared using an “in vivo cryotechnique” (IVCT) and examined immunohistochemically with specific antibodies
against phospho-(Ser/Thr) PKA/C substrate (P-PK-S) and phospho-(Ser/Thr) Akt substrate (P-Akt-S) to capture their time-dependent
regulation in vivo. Left kidneys were cryofixed with IVCT under normal blood circulation and after varying hypoxic intervals,
followed by freeze-substitution with acetone containing paraformaldehyde. Deparaffinized sections were immunostained for P-PK-S,
Na+/HCO3
− cotransporter NBC1, and a membrane skeletal protein, 4.1B. The P-PK-S was diffusely immunolocalized in the cytoplasm of the
proximal tubules in normal kidneys, whereas NBC1 and 4.1B were detected at the basal striations of S1 and S2 segments of the
proximal tubule. After 10 or 30 s hypoxia, P-PK-S was still immunolocalized in the cytoplasm of kidneys, but it was detected
at the basal striations after 1 or 2 min hypoxia. The immunolocalization of P-Akt-S was the same as P-PK-S in the normal and
hypoxic kidneys. Immunoblotting analyses of the kidney tissues under normal or hypoxic condition clearly identified the same
40-kDa bands. The IVCT is useful for time-dependent analysis of the immunodistribution of P-PK-S and P-Akt-S. 相似文献
90.