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81.
Preimplantation genetic diagnosis is introduced for prevention of genetic disorders. The combination of in vitro fertilization technique and single cell molecular genetic diagnosis allows only unaffected embryos to be selected for embryotransfer, providing a healthy pregnancy and so also avoiding the need for its possible termination. CASE REPORT: The authors report the first successful case of the clinical application of preimplantation genetic diagnosis in Hungary, resulting the birth of an unaffected baby. Preembryonal biopsy and subsequent fluorescent-PCR analysis of the blastomeres taken from the preembryos of a woman who is a carrier for Duchenne muscular dystrophy was performed. Sexing of the preembryos by X and Y chromosome specific primers were performed and three female preembryos were found. RESULT: All three preembryos were transferred into the uterus, which resulted a singleton pregnancy, resulting the birth of a healthy female baby. The authors are offering preimplantation genetic diagnosis with sexing for couples, who are at risk of having a child with X-linked diseases, or are carriers for the delta-F508 mutation of cystic fibrosis. CONCLUSIONS: The application of this diagnostic tool is also planned for other monogenic disorders. 相似文献
82.
INTRODUCTION: Heterotaxy syndrome (Ivemark syndrome, or asplenia-polysplenia syndrome) is a heterogeneous group of disease with disturbed body symmetry and malposition of internal organs. Heterotaxy syndrome is caused by the disturbance of the left/right axis in the early embryonic period. AIM OF THE STUDY: The most frequency of heterotaxy syndrome's concomitant anomalies during a five year period in own fetopathology material. MATERIALS AND METHODS: Data of fetopathologic examination of 13 fetuses suffering from prenatally diagnosed heterotaxy syndrome. RESULTS: Situs ambiguus was detected in 9 cases out of 13. In the remaining 4 cases situs inversus totalis was diagnosed. The most frequent and important associated malformation included congenital heart disease was AV channel (10/13) and great vessel anomaly (10/13). CONCLUSION: In cases with prenatally detected complex cardiac anomalies (especially AV channel cases) heterotaxy anomaly must be taken into consideration, with main consequences in prenatal counselling. 相似文献
83.
Objective: Ischemic stroke is a frequent heterogeneous multifactorial disease that is affected by several genetic mutations and environmental
factors. We hypothesised the clinical importance of the co-occurrence of common, unfavorable genetic mutations in the development
of different stroke subtypes. Method and material: The Factor V Leiden G1691A (Leiden V), the prothrombin G20210A and the methylenetetrahydrofolate reductase C677T (MTHFR C677T)
mutations and the angiotensin-converting enzyme I/D (ACE I/D) and apolipoprotein E (APOE) genotypes were examined by the PCR
technique in 689 ischemic stroke patients and 652 stroke-free controls. Logistic regression models were used to estimate the
relative risks of different stroke subtypes for different genotype combination patterns. Results: The ACE D/D genotype alone or in combination with the MTHFR 677T or the APOE 4 allele or with both was highly specific for
small-vessel infarction. The Leiden V mutation alone or in different combination patterns with the ACE D, APOE 4 and MTHFR
677T alleles was specifically predisposed to large-vessel infarction. The APOE 4 allele alone was calculated to be a general,
minor genetic risk factor for ischemic stroke. The MTHFR 677T allele alone was not a risk factor for any stroke subtype. In
the different specific predisposition gene combinations, however, both the APOE 4 and MTHFR 677T alleles could increase the
relative risk of the given stroke subgroup. Conclusions: Common mutations which alone are minor or non-significant risk factors for ischemic stroke can yield, in specific combination
patterns, a highly significant, moderate genetic risk of specific stroke subtypes.
Received: 5 February 2002, Received in revised form: 17 April 2002, Accepted: 22 April 2002
Correspondence to Dr. Z. Szolnoki, M. D. 相似文献
84.
Beta-amyloid-induced increase in the resting intracellular calcium concentration gives support to tell Alzheimer lymphocytes from control ones 总被引:3,自引:0,他引:3
Senile plaques containing beta-amyloid peptide (betaAP) comprise the major neuropathological lesions in Alzheimer's disease (AD). In line with ongoing studies investigating alterations of various biochemical processes of cells of peripheral tissues, the authors demonstrate differences in resting intracellular free calcium levels of lymphocytes harvested from sporadic Alzheimer patients and from age-matched controls. Resting intracellular calcium concentration was measured in Fura-2AM-loaded human lymphocytes by dual wavelength spectrofluorimetry. Resting calcium level appeared to be higher in Alzheimer cells when compared to control lymphocytes. After incubating cells in 10(-7)M of beta-amyloid, the resting calcium concentration of the control cells elevated, while that of Alzheimer lymphocytes did not differ considerably. 相似文献
85.
Mangel L Skriba Z Major T Polgár C Fodor J Somogyi A Németh G 《Acta oncologica (Stockholm, Sweden)》2002,41(2):162-168
The purpose of this study was to prove that by using conformal external beam radiotherapy (RT) normal brain structures can be protected even when applying an alternative approach of biological dose escalation: hypofractionation (HOF) without total dose reduction (TDR). Traditional 2-dimensional (2D) and conformal 3-dimensional (3D) treatment plans were prepared for 10 gliomas representing the subanatomical sites of the supratentorial brain. Isoeffect distributions were generated by the biologically effective dose (BED) formula to analyse the effect of conventionally fractionated (CF) and HOF schedules on both the spatial biological dose distribution and biological dose-volume histograms. A comparison was made between 2D-CF (2.0 Gy/day) and 3D-HOF (2.5 Gy/day) regimens, applying the same 60 Gy total doses. Integral biologically effective dose (IBED) and volumes received biologically equivalent to a dose of 54 Gy or more (V-BED54) were calculated for the lower and upper brain stem as organs of risk. The IBED values were lower with the 3D-HOF than with the 2D-CF schedule in each tumour location, means 22.7+/-17.1 and 40.4+/-16.9 in Gy, respectively (p < 0.0001). The V-BED54 values were also smaller or equal in 90% of the cases favouring the 3D-HOF scheme. The means were 2.7+/-4.8 ccm for 3D-HOF and 10.7+/-12.7 ccm for 2D-CF (p = 0.0006). Our results suggest that with conformal RT, fraction size can gradually be increased. HOF radiotherapy regimens without TDR shorten the treatment time and seem to be an alternative way of dose escalation in the treatment of glioblastoma. 相似文献
86.
Cserni G Kovács BR Tarján M Sápi Z Domján Z Szabó Z 《Pathology oncology research : POR》2002,8(2):142-144
Both chromophobe carcinoma and sarcomatoid carcinoma of the kidney are rare. The former is characterized by a relatively good prognosis, while the latter is a highly aggressive tumor. Coexistence of the two components in one renal tumor, which has been reported only rarely, is therefore paradoxical. Both sarcomatoid and chromophobe renal carcinoma were diagnosed in a 52-year-old woman following nephrectomy and resection of metastases in the right lobe of the liver. She died of the disease two months after the first operation; only the sarcomatoid component of her tumor was seen in the liver metastasis and the recurrent carcinoma. Differences in phenotype, immunophenotype and DNA-ploidy patterns of the two components are reported. The intensive p53 staining observed only in the sarcomatoid area supports the role of the TP53 gene in the transformation of chromophobe renal carcinoma to sarcomatoid carcinoma. 相似文献
87.
Lateralization as a factor in the prognosis of middle cerebral artery territorial infarct 总被引:3,自引:0,他引:3
The consequences of cerebral infarcts involving the left hemisphere differ from those of the right homologue areas. Data of 337 consecutive, unselected patients with acute ischaemic stroke in the territory of the right or left middle cerebral artery were analysed. Furthermore, lesion locations of 77 stroke patients with early death were compared with those of 315 patients followed for more than 28 days. Without any differences in stroke severity and in the volume of the lesions, the outcome of strokes of the right hemisphere was less favourable, and the case fatality rate was higher than in controls during a 10-year follow-up period. The rate of early death due to cardiogenic cause was relatively higher in the right hemispherical group. The asymmetry of the sympathetic nervous system, and the distinct psychosyndromes following the injury of the two hemispheres may underlie this difference in prognosis. 相似文献
88.
Permanent or temporary disruption of cerebral blood flow rapidly depletes brain regions of their limited energy reserves (glycogen, glucose, oxygen, ATP) leading to an energy crisis. Tissue damage occurs due to the energy crisis. The central part of the damage, the ischaemic "core" region is surrounded by zones of the shell-like penumbra. Necrotic, as well as apoptotic cell death could be identified in the penumbra. Going away from the ischaemic core different neurochemical processes are occurring by space and time. "Immediate early response" genes (c-fos, fos-B, c-Jun, krox 20, 24) are activated, heatshock proteins (hsp 70, 72, HSF, HSE, HIF), cytokines (TNF-alpha, IL-1 beta), inflammatory factors (COX), adhesion and glial factors (ICAM-1, ELAM-1, P-selectin), vasoactive factors (IL-6, -10, PAF), reactive oxigen radicals and connected factors (O2, OH, NO, NOS, SOD) are produced within minutes and hours. Cell deaths, necrosis and apoptosis due to the activation of calpains, caspases and nucleases occur in days. In parallel, growth factors and plasticity proteins (BDNF, NGF, TGF-beta, VEGF, PDGF, GAP-43) are activated as a basis of functional rehabilitation. 相似文献
89.
Life-threatening, complete middle cerebral artery infarction occurs in up to 10% of all stroke patients. The "malignant media occlusion" is an infarction occupying more than 50% of middle cerebral artery territory. The malignant, space-occupying supratentorial ischemic stroke is characterised by a mortality rate of up to 80%. Several reports indicate, that hemicraniectomy in this situation can be life-saving. Hemicraniectomy increases cerebral perfusion pressure and optimises retrograde perfusion via the leptomeningeal collateral vessels. A case of a patient is presented, having progressive neurological deterioration due to massive cerebral infarctions. The patient rehabilitation was successful. Decompressive surgery is life saving and can also give acceptable functional recovery. Hemorrhagic stroke is due to stroke in 15% of cases and in 10%, it is "spontaneous" intracerebral hematoma. The intracerebral and intraventricular hemorrhage represents one of the most devastating types of stroke associated with high morbidity and mortality. The 30-day mortality rate is 35% to 50% and most survivors are left with a neurological disability. The value of surgical therapy is debatable. The aspiration and urokinase therapy of the hematoma of intracerebral hemorrhage could improve final neurological outcome. Spontaneous, nontraumatic intraventricular hemorrhage frequently carries a grave prognosis. A large part of morbidity after intraventricular hemorrhage is related to intracranial hypertension from hydrocephalus. One patient presented had intracerebral hemorrhage and another had intraventricular hemorrhage treated with urokinase. Rapid and extensive reduction in the amount of intracerebral and intraventricular blood occurred. Urokinase lysis is safe and can be a potentially beneficial intervention in intracerebral and intraventricular hemorrhage. By performing decompressive craniectomy, the neurologists of stroke departments and intensive care units with the neurosurgeons will have to play major role in the management of stroke patients. 相似文献
90.