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1.
A. Decoster F. Darcy A. Caron D. Vinatier D. Houze De L''''Aulnoit G. Vittu G. Niel F. Heyer B. Lecolier M. Delcroix J. C. Monnier M. Duhamel A. Capron 《Clinical and experimental immunology》1992,87(2):310-315
This study extends a previous study and confirms that the detection of anti-P30 IgA antibodies is very helpful in the diagnosis of acute acquired or congenital toxoplasmosis. Moreover, we demonstrate that an anti-P30 IgA response can be mounted in the fetuses infected by Toxoplasma gondii during their intra-uterine life as early as week 23 of gestation. A double-sandwich ELISA described in our previous work was used to detect anti-P30 IgA antibodies in 1378 human serum samples collected from 551 patients, including 162 fetuses whose mothers had been infected by T. gondii during pregnancy, 46 congenitally infected and 90 uninfected newborns and 253 women suspected of having been infected during pregnancy, including the mothers of fetuses and newborns previously described. Anti-P30 IgA antibodies were detected in all cases of acute toxoplasmosis but in no case of chronic toxoplasmosis: in the majority of cases, the IgA antibody titre fell below cut-off in 3-9 months. Among the 46 congenitally infected newborns, anti-P30 IgA antibodies were detected in sera of 41 infected newborns (38 at birth, two in the first months of life, one in the seventh month of life), while anti-P30 IgM antibodies were detected in only 30 cases at birth and in one case during the first month of life. Among 162 fetuses, anti-P30 IgA response was observed in five infected fetuses, but was not detected in either 152 uninfected fetuses or in five fetuses considered as infected. The absence or presence of anti-P30 IgA antibodies in the fetus is discussed in relation to the date of maternal infection and collection of the fetal blood. It clearly appears from our study that the combined testing of both IgM and IgA in the fetus and the newborn is essential for a more efficient diagnosis of infection. 相似文献
2.
Human isolates of the highly prevalent TT virus (TTV) have been classified into five major genomic groups (1-5). The geographical distribution of the groups throughout the world is not well known. Five different PCR assays were developed in an attempt to amplify specifically TTV DNAs of each genomic group. Serum samples collected from 72 Brazilian adults (24 voluntary blood donors, 24 hepatitis B virus (HBV) carriers, and 24 human immunodeficiency virus type 1 (HIV-1)-infected patients) were tested. TTV DNA from at least one genomic group was detected in 11 (46%) blood donors, 13 (54%) HBV carriers, and 24 (100%) HIV-1 patients. All five genomic groups were detected in the three populations, with the exception of group 2 in blood donors. Some samples, negative with all five specific assays, were positive with the commonly used untranslated region (UTR) PCR system. On the other hand, TTV DNA was detected in some samples by using specific assays but not with the UTR PCR. Mixed infections with 2-5 TTV isolates from different groups were detected in 21% blood donors, 29% HBV carriers, and 71% HIV-1 patients. Fifteen PCR products (three obtained with each assay) were sequenced. Most sequences showed high (>86%) homology with those of TTV isolates belonging to their presumed groups. However, three sequences had low homology with all TTV sequences available from the DNA databanks. In conclusion, TTV isolates belonging to all five known genomic groups circulate in Brazil, and the results suggest the existence of new and as yet uncharacterised major genomic groups. 相似文献
3.
Dr. L. Hens C. Plets R. Dom L. Velghe 《Journal of molecular medicine (Berlin, Germany)》1979,57(14):741-746
Summary A case of endocrinologically active glomus jugulare is presented. The localization within the tumor of the catecholamine hyperproduction was demonstrated by selective venous sampling from the vena jugularis externa draining the tumor.The norepinephrine/epinephrine ratio was high and of the same order in blood, urine and cerebrospinal fluid. Bioassay showed high levels of intratumoral norepinephrine and epinephrine.The ways of treatment and their influence on the catecholamines are briefly discussed. In every phaeochromocytoma-like syndrome both the existence of catecholamine hyperproduction and the anatomical site of this hypersecretion have to be precisely documented in order to define the correct treatment to be applied. 相似文献
4.
Summary The distribution of cytarabine in the ventricular CSF was studied after lumbar intrathecal administration. In the ventricular fluid peak concentrations up to 1.5×10–4 M (37 g/ml) were achieved 4–8 h after lumbar injection of cytarabine of 45 mg/m2. The concentration of cytarabine decreased slowly with a half-time of 2.16 h thus providing therapeutic concentrations in the cerebral ventricles for more than 24 h.
Zusammenfassung Die Verteilung von Cytosinarabinosid nach lumbaler intrathekaler Injektion im ventrikulären Liquor cerebrospinalis wurde untersucht.Nach lumbaler intrathekaler Injektion von 45 mg Cytosinarabinosid (Alexan®) pro m2 Körperoberfläche wurde im ventrikulären Liquor eine Höchstkonzentration von 1,5×10–4 M (37 g/ml) 4–8 h nach Applikation erreicht. Die Konzentration von Cytosinarabinosid im ventrikulären Liquor fiel langsam mit einer Halbwertszeit von 2,16 h ab. Bei lumbaler Applikation wurden bei dieser Untersuchung therapeutische Konzentrationen von Cytosinarabinosid in den cerebralen Ventrikeln für mehr als 24 h erreicht.相似文献
5.
The effects on the nicotinic activation of the coeliac plexus neurons of nitric oxide (NO) released within the coeliac plexus by gastric mechanoreceptors, in particular during gastroduodenal inhibitory reflex, were assessed. This study was performed in the rabbit on an in vitro preparation of the coeliac plexus connected to the stomach and the duodenum. The electrical activity of ganglionic neurons was recorded with intracellular recording techniques. Water-filled balloons were used for gastric distensions and recording of duodenal motility. When a 10-s train of pulses (20-40Hz) of supramaximal intensity was applied to the splanchnic nerves, gradual depression of nicotinic activation occurred. Gastric distension (50 mL, 7.5 min) modulated this depression phenomenon by inhibiting or facilitating the nicotinic activation. In the neurons impaled during the recording of duodenal motility, gastric distension triggered an inhibition of nicotinic activation concomitantly with a gastroduodenal inhibitory reflex organized by the coeliac plexus. If the gastric distensions were performed while the coeliac plexus was superfused by a NO scavenger, the nicotinic activation was unaffected and the gastroduodenal inhibitory reflex was abolished. Moreover, when the coeliac plexus was superfused with an inhibitor of nitric oxide synthase, gastric distensions were without effect on the nicotinic activation. These results demonstrate that NO released within the coeliac plexus by gastric mechanoreceptors, in particular during the gastroduodenal inhibitory reflex, modulates the central nicotinic activation of coeliac plexus neurons, so NO released within a prevertebral ganglion by gastric afferent fibres, in particular during the organization by this ganglion of a reflex regulating the gastrointestinal tract motility, also exerts a gating of the central inputs to the ganglionic neurons. 相似文献
6.
Wim Delva Fei Meng Roxanne Beauclair Nele Deprez Marleen Temmerman Alex Welte Niel Hens 《Journal of the International AIDS Society》2013,16(1)
Introduction
A decreased frequency of unprotected sex during episodes of concurrent relationships may dramatically reduce the role of concurrency in accelerating the spread of HIV. Such a decrease could be the result of coital dilution – the reduction in per-partner coital frequency from additional partners – and/or increased condom use during concurrency. To study the effect of concurrency on the frequency of unprotected sex, we examined sexual behaviour data from three communities with high HIV prevalence around Cape Town, South Africa.Methods
We conducted a cross-sectional survey from June 2011 to February 2012 using audio computer-assisted self-interviewing to reconstruct one-year sexual histories, with a focus on coital frequency and condom use. Participants were randomly sampled from a previous TB and HIV prevalence survey. Mixed effects logistic and Poisson regression models were fitted to data from 527 sexually active adults reporting on 1210 relationship episodes to evaluate the effect of concurrency status on consistent condom use and coital frequency.Results
The median of the per-partner weekly average coital frequency was 2 (IQR: 1–3), and consistent condom use was reported for 36% of the relationship episodes. Neither per-partner coital frequency nor consistent condom use changed significantly during episodes of concurrency (aIRR=1.05; 95% confidence interval (CI): 0.99–1.24 and aOR=1.01; 95% CI: 0.38–2.68, respectively). Being male, coloured, having a tertiary education, and having a relationship between 2 weeks and 9 months were associated with higher coital frequencies. Being coloured, and having a relationship lasting for more than 9 months, was associated with inconsistent condom use.Conclusions
We found no evidence for coital dilution or for increased condom use during concurrent relationship episodes in three communities around Cape Town with high HIV prevalence. Given the low levels of self-reported consistent condom use, our findings suggest that if the frequency of unprotected sex with each of the sexual partners is sustained during concurrent relationships, HIV-positive individuals with concurrent partners may disproportionately contribute to onward HIV transmission. 相似文献7.
Dammers R Planken RN Pouls KP Van Det RJ Burger H Van Der Sande FM Tordoir JH 《Journal of vascular surgery》2003,37(1):143-148
OBJECTIVE: Prosthetic arteriovenous fistulas for hemodialysis vascular access have a high incidence rate of thrombotic occlusions that result in graft failure. This randomized multicenter study was performed to assess the patency rates and the effect of 4-mm to 7-mm grafts on the development of stenoses. METHODS: A total of 109 patients who needed vascular access for hemodialysis were randomized to receive either 6-mm (n = 57) or 4-mm to 7-mm prosthetic brachial-antecubital forearm loop accesses (polytetrafluoroethylene). Duplex scanning, with measurement of blood flow and peak systolic velocity and detection of stenoses (>50%), was performed at 1, 6, and 12 months after surgery. Clinical data were obtained in a prospective manner and primary, assisted primary, and secondary patency rates were calculated with the Kaplan-Meier life-table analysis. Statistical analysis was performed with the independent samples t test and chi(2) test. RESULTS: At 1 year, patency rates were similar for both 4-mm to 7-mm and 6-mm prostheses (primary, 46% versus 43%; assisted primary, 62% versus 58%; secondary, 87% versus 91%). The incidence rate of thrombotic occlusion was comparable for both groups (0.74/patient-year versus 0.88/patient-year; P >.05). Mean graft flow at 1, 6, and 12 months was 1416 versus 1415 mL/min, 1345 versus 1319 mL/min, and 1595 versus 1265 mL/min (P >.05) for 4-mm to 7-mm and 6-mm grafts, respectively. Also, no differences in peak systolic velocities in any part of the grafts were observed. The percentage of stenoses detected was equal in both groups at 1 year after surgery (27% versus 20%; P >.05). CONCLUSION: A 4-mm to 7-mm tapered prosthetic brachial-antecubital forearm loop access did not reduce the incidence rates of stenoses and thrombotic occlusions compared with a 6-mm prosthetic conduit. Moreover, no differences in patency rates were observed. Therefore, we believe that the 4-mm to 7-mm graft should not be used routinely for hemodialysis vascular access. 相似文献
8.
ABSTRACT:: Centromedullary pinning provides an excellent alternative to open reduction in severely displaced radial neck fractures. It has a low complication rate because it is an extra-articular and minimally invasive technique. The functional results have been shown to be good or excellent in most cases. The technique is described clearly in the literature but has posed us with certain difficulties. We present a useful technical tip on performing centromedullary pinning based on our experience of treating radial neck fractures by this method. 相似文献
9.
The introduction of comprehensive testing techniques, such as microarray technology or whole genome sequencing, in embryo testing has the potential to change the practice of Preimplantation Genetic Diagnosis (PGD) and Preimplantation Genetic Screening (PGS). However, the extra information these procedures yield may potentially generate dilemmas for couples and professionals regarding the scope of the tests and the selection of the right embryo. In order to understand this complexity and reflect on its consequences, we organized two expert panels consisting of professionals working in the field of assisted reproduction and/or genetics. We found that there is great uncertainty amongst professionals how to tackle questions related to comprehensive screening, such as which conditions to test for and who should have the final say on which embryo to select, and a lack of a framework from which such questions can be answered. Moreover, the complexity of genetic information comprehensive tests may yield may make it impossible to select the best embryo altogether. 相似文献
10.
Clarisse Boët Sophie Fugier Julie Marsault Déborah Toublan Marie-Eve Valot Arthur Cheval Gonzague Amyot d'Inville Stéphane Niel Pierre Guihéneuc Gilles Guihard 《International journal of osteopathic medicine : IJOM》2013,16(3):131-142
BackgroundHigh-velocity low-amplitude thrust manipulations (HVLAM) are routinely used in osteopathic treatment. Despite the large number of studies that have been realized till now, the effects of spinal HVLAM on the physiological properties of muscles and nerves are not fully characterized.ObjectiveThe present study was designed to investigate the effects of a spinal lumbar L4/L5 HVLAM on the functional properties of the soleus T reflex in asymptomatic young adults.DesignControlled pre/post measures experimental design.MethodsRight and left soleus T reflexes were elicited by striking right and left Achilles tendons with an instrumented reflex hammer and the electromyographic (EMG) signals were monitored in right and left soleus muscles. The amplitude and latency of EMG responses were measured before and after the delivery of a HVLAM targeting the L4/L5 segment. The conduction velocity was calculated from the latency value.Subjects50 asymptomatic adults met all inclusion criteria. They were randomly allocated to either group a) receiving a sham manipulation (SM), or b) a HVLAM. Because of subject loss, the final size of SM and HVLAM groups was 24 and 18, respectively.ResultsOur data show that the conduction velocity, but not the amplitude of the T reflex, is significantly increased by HVLAM in both soleus muscles with small to medium effect size. SM neither changes the amplitude nor modifies the conduction velocity.ConclusionOur data show that a lumbar L4/L5 HVLAM modifies the electrophysiological properties of the soleus T reflex. 相似文献