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991.
Symptomatic overdrainage of cerebrospinal fluid (CSF) can be seen in shunted hydrocephalus patients and in non-shunted patients with spontaneous intracranial hypotension (SIH). In these patients, intracranial pressure (ICP) monitoring often reveals negative static ICP, while it is less understood how the pulsatile ICP (cardiac induced ICP waves) is affected. This latter aspect is addressed in the present study. A set of 40 ICP recordings from paediatric and adult hydrocephalus patients were randomly selected. Each cardiac induced ICP wave was automatically identified and manually verified by the beginning and ending diastolic minimum pressures and the systolic maximum pressure. The ICP wave parameters (static pressure, amplitude, rise time, rise time coefficient, downward coefficient, wave duration, and area-under-curve) were then automatically computed. The material of 40 ICP recordings provided a total of 3,192,166 cardiac induced ICP waves (1,292,522 in paediatric patients and 1,899,644 in adult patients). No apparent changes in ICP wave parameters were seen when mean ICP became negative, except that the parameters amplitude, rise time coefficient, downward coefficient and area under curve somewhat increased when mean ICP was below -15 mmHg. 相似文献
992.
Ferrari G Kozarski M Zieliński K Fresiello L Di Molfetta A Górczyńska K Pa?ko KJ Darowski M 《Journal of artificial organs》2012,15(1):32-43
Aim of this work was to develop a modular computational model able to interact with ventricular assist devices (VAD) for research
and educational applications. The lumped parameter model consists of five functional modules (left and right ventricles, systemic,
pulmonary, and coronary circulation) that are easily replaceable if necessary. The possibility of interacting with VADs is
achieved via interfaces acting as impedance transformers. This last feature was tested using an electrical VAD model. Tests
were aimed at demonstrating the possibilities and verifying the behavior of interfaces when testing VADs connected in different
ways to the circulatory system. For these reasons, experiments were performed in a purely numerical mode, simulating a caval
occlusion, and with the model interfaced to an external left-VAD (LVAD) in two different ways: with atrioaortic and ventriculoaortic
connection. The caval occlusion caused the leftward shift of the LV p–v loop, along with the drop in arterial and ventricular pressures. A narrower LV p–v loop and cardiac output and aortic pressure rise were the main effects of atrioaortic assistance. A wider LV p–v loop and a ventricular average volume drop were the main effects of ventricular-aortic assistance. Results coincided with
clinical and experimental data attainable in the literature. The model will be a component of a hydronumerical model designed
to be connected to different types of VADs. It will be completed with autonomic features, including the baroreflex and a more
detailed coronary circulation model. 相似文献
993.
Bo?ena Moskwa Katarzyna Go?dzik Justyna Bień Marek Bogdaszewski W?adys?aw Cabaj 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2012,57(4):402-405
Trichinella larvae were detected in a marten (Martes martes) and a badger (Meles meles) in Poland. The animals were found dead following car accidents. All examined animals derived from the Mazurian Lake district, north-east Poland, near the village Kosewo Górne where Trichinella infection were earlier confirmed in wildlife; red foxes and wild boars. The muscle samples were examined by artificial pepsin-HCl digestion method. The parasites were identified as Trichinella britovi by multiplex polymerase chain reaction method. Larvae were found in two out of three martens and one out of seven examined badgers. This is the first report of the identification of Trichinella britovi larvae from martens and badgers in Poland. 相似文献
994.
Rievaj J Davidson C Nadeem A Hollenberg M Duszyk M Vliagoftis H 《Pflügers Archiv : European journal of physiology》2012,463(3):497-509
Protease-activated receptor 2 (PAR-2) is a G protein-coupled receptor possibly involved in the pathogenesis of asthma. PAR-2
also modulates ion transport in cultured epithelial cells, but these effects in native airways are controversial. The influence
of allergic inflammation on PAR-2-induced changes in ion transport has received little attention. Here, we studied immediate
changes in transepithelial short circuit current (I
sc) induced by PAR-2 activation in the tracheas of naive and allergic mice. Activation of PAR-2 with an apically added activation
peptide (AP) induced a small increase in I
sc, while a much larger increase was observed following basolateral AP addition. In ovalbumin-sensitized and -challenged animals
used as a model of allergic airway inflammation, the effect of basolateral AP addition was enhanced. Responses to basolateral
AP in both naive and allergic mice were not decreased by blocking sodium absorption with amiloride or CFTR function with CFTRinh172 but were reduced by the cyclooxygenase inhibitor indomethacin and largely blocked (>80%) by niflumic acid, a calcium-activated
chloride channels’ (CaCC) blocker. Allergic mice also showed an enhanced response to ATP and thapsigargin. There was no change
in mRNA expression of Par-2 or of the chloride channels Ano1 (Tmem16a) and Bestrophin 2 in tracheas from allergic mice, while
mRNA levels of Bestrophin 1 were increased. In conclusion, basolateral PAR-2 activation in the mouse airways led to increased
anion secretion through apical CaCC, which was more pronounced in allergic animals. This could be a protective mechanism aimed
at clearing allergens and defending against mucus plugging. 相似文献
995.
Szczygiel AM Brzezinka G Targosz-Korecka M Chlopicki S Szymonski M 《Pflügers Archiv : European journal of physiology》2012,463(3):487-496
Tumor necrosis factor alpha (TNF-α) is a critical cytokine that is involved in systemic inflammatory response and contributes to the activation of the pro-inflammatory
phenotype of the endothelium. In the present study, effects of TNF-α on morphology and elasticity of endothelium in relation to the production of NO and actin fiber reorganization were analyzed
in human dermal microvascular endothelial cells. The cells were incubated in MCDB medium solution and stimulated with
10 \textng/ml10\;\text{ng/ml} of TNF-α. Atomic force microscopy measurements have enabled characterization of cell morphology and elastic properties in physiological
conditions. The spectrophotometric Griess method was applied to estimate nitric oxide (NO) production of the cells. We demonstrated
that TNF-α-induced changes in elasticity of endothelium anti-correlate with NO production and are associated with the reorganization
of actin cytoskeleton. 相似文献
996.
Rakus KŁ Irnazarow I Adamek M Palmeira L Kawana Y Hirono I Kondo H Matras M Steinhagen D Flasz B Brogden G Vanderplasschen A Aoki T 《Developmental and comparative immunology》2012,37(1):65-76
Cyprinid herpesvirus 3 (CyHV-3), also known as koi herpesvirus (KHV), is the etiological agent of a virulent and lethal disease in common and koi carp. This study aimed to determine the genetic basis underlying the common carp immune response to the CyHV-3 virus. Two common carp lines (R3 and K) were infected with CyHV-3 by immersion. The R3 line presented a 20% higher survival rate compared to the K line and significantly lower viral loads as measured at day 3 post infection (p.i.). Microarray analysis using a common carp slides containing a number of 10,822 60-mer probes, revealed that 581 genes in line K (330 up-regulated, 251 down-regulated) and 107 genes in line R3 (77 up-regulated, 30 down-regulated), showed at least a 2-fold difference in expression at day 3 p.i. compared to day 0. Genes which showed at least a 4-fold difference in expression in both lines were selected as potential markers of a CyHV-3 infection in common carp. Additionally, 76 genes showed at least 2-fold differentially expression between K and R3 lines at day 3 p.i. Significantly higher expression of several immune-related genes including number of those which are involve in pathogen recognition, complement activation, MHC class I-restricted antigen presentation and development of adaptive mucosal immunity was noted in more resistant R3 line. Further real-time PCR based analysis provided evidence for higher activation of CD8(+) T cells in R3 line. This study uncovered wide array of immune-related genes involved into antiviral response of common carp toward CyHV-3. It is also demonstrated that the outcome of this severe disease in large extent could be controlled by genetic factors of the host. 相似文献
997.
The present study describes the development of a SYBR Green based real-time polymerase chain reaction (real-time PCR) for detection and quantitation of all fowl adenovirus (FAdV) species. Primers were designed based on conserved nucleotide sequences within the 52K gene. Ten-fold serial dilutions of a vector DNA were used as standard for quantitation. The real-time PCR had an efficiency of 98%, a regression squared value of 0.999 and showed a range of 6.73-6.73×10(8) copies of FAdV DNA per reaction. The assay was highly specific for FAdVs and an exact quantitation of all 5 FAdV species (FAdV-A to FAdV-E) could be demonstrated. It was shown, that twelve FAdV serotypes (FAdV-1 to 8a, and 8b to 11) were detectable and quantifiable. Other viral genomes as well as uninfected chicken embryo liver (CEL) cells did not produce positive signal. Cloacal swabs were taken during the animal experiment, which was performed with all FAdV species. Shedding of FAdVs was investigated in cell culture, by conventional PCR and by the developed real-time PCR. The real-time PCR was found more sensitive than cell culture and conventional PCR. Detection and quantitation of FAdVs in different type of samples was possible by the new real-time PCR. 相似文献
998.
Since herbal teas, infusions and decoctions prepared from medicinal plants are popular remedies, it remains a topical question whether these herbal drugs can be treated as sources of essential elements for humans, who often use them in their everyday diet. Therefore, total and water-extractable contents of Mg, Mn and Cu were determined in 41 leaves originating from four botanical species of Plantago lanceolata, Arctostaphyllos uva-ursi, Rubus fruticosus and Betula sp., as well as in 33 samples of herbs represented by three species of Urtica dioica, Hypericum perforatum and Achillea millefolium. The highest level was determined in the case of Mg (in a range from 2.0 to 7.0 mg/g of dry mass [d.m.]), followed by Mn (from 50.0 to 1300.0 mg/kg d.m.), and lowest of all, Cu (from 3.5 to 19.5 mg/kg d.m.). Student's t-test showed that a statistically significant difference exists between samples originating from different plant species regarding the total content and water-extractable forms of Mg, Mn and Cu. By analysis of the relations between elements, it was observed that total level of Cu correlated with total levels of Mg and Mn, which indicates a synergistic interaction between the essential elements under study. With regard to Dietary Reference Intakes (DRIs), the leaves of Rubus fruticosus contained the highest amounts of a water-extractable bioavailable form of Mn, which guarantees from 160 to 200% of the daily requirement of Mn for women and men, respectively. On the other hand, the extract obtained from Urticae folium gave water-extractable Mg in the amount of 76 mg/500 mL, which constitutes about 20% of daily requirement. The plant material richest in water-extractable Cu was Hyperici herba, containing 154.5 microg/500 mL, or 17% of DRI for both sexes. 相似文献
999.
Empty sella syndrome is a consequence of the herniation of the subarachnoid space within the sella associated with flattering of the pituitary gland. In this paper, we describe the atypical clinical manifestation of this condition in a 27-year-old survivor of thyroid cancer. We associate the development of empty sella syndrome in this subject with normalization of levothyroxine treatment in conditions of long-lasting and inaccurately managed thyroid ablation-induced hypothyroidism. Administration of hydrocortisone and implementation of hypogonadism treatment together with the appropriate management of hypothyroidism led to a significant improvement in the patient's condition. 相似文献
1000.