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Summary We have examined the nonparallel changes in tampanic membrane temperatures (T ty) from the two ears in response to various changes in body and head positions. Upon assuming a lateral recumbent position, the T ty on the lower side increased while that on the upper side decreased. Pressure application over a wide area of the lateral chest only caused inconsistent and obscure asymmetric changes in T ty. A lateral flexion of the head with the subject sitting upright and a rotation of the head to the side in a supine position induced an increase in the T ty on the lower side compared to that on the upper side. The temperature and blood flow of the forehead often decreased on the lower side and increased on the upper side, although such responses were not always concomitant with the asymmetric changes in T ty. A dorsal flexion of the head with the subject in a reclining position caused a slight increase in the T ty, whereas raising the head upright induced a slight decrease in them. Two additional experiments were carried out with single photon emission computed tomography using 99mTc-hexamethylpropyleneamine oxime as tracer, and a slight, relative decrease in counts was noted in the right hemisphere during rotation of the head to the right. These results would strongly suggest that unilateral increases and decreases in T ty could have been caused by one-sided decreases and increases, respectively, in blood flow to the brain and/or the tympanic membrane, induced by a vasomotor reflex involving vestibular stimulation.  相似文献   
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Pelizaeus — Merzbacher disease (PMD) is an X-linked neurologicaldisorder characterized by dysmyelination in the central nervoussystem (CNS). Recently mutations of the myelln proteollpid protein(PLP) gene which encodes both PLP and Its Isoform, DM-20 generatedby alternative spllcing, have been demonstrated In PMD patients.We analyzed the seven exons of the PLP gene of a Japanese boyaffected with PMD by direct sequencing and identified an Insertionevent In exon Vll of the PLP gene. This mutation was also presentIn his carrier mother, but was absent In ninety-five X chromosomesof normal Japanese. The frame-shift mutation leads to the productionof truncated PLP with altered carboxyl terminal amlno acid sequences,resulting In conslderable change of the structure of PLP andDM-20 necessary for functional purposes. This is the first reportof a mutation In exon Vll of the PLP gene associated with PMD.  相似文献   
15.
We describe a de novo balanced reciprocal translocation between the long arms of chromosomes 5 and 8 [46,XX,t(5;8)(q35;q24.1)] in a 15-month-old girl with a typical Sotos syndrome phenotype. Involvement of the 5q35 region was previously reported (Maroun et al. [1994: Am J Med Genet 50:291-293]) as one of translocation breakpoints in the present patient. We suggest that the gene responsible for Sotos syndrome is located to a distal long-arm region of chromosome 5.  相似文献   
16.
BACKGROUND: The [PSI+] element of the budding yeast is an aggregated form of the translation release factor Sup35 that is propagated and transmitted cytoplasmically in a manner analogous to that of mammalian prions. The N-terminal of Sup35, necessary for [PSI+], contains oligopeptide repeats and multiple Gln/Asn residues. RESULTS: We replaced the Gln/Asn-rich prion repeats of Sup35 with non-Gln/Asn repeats from heterologous yeast strains. These non-Gln/Asn repeat Sup35s propagated a novel [PSI+] variant, [PHI+], that appeared de novo 103 times more frequent than [PSI+]. [PHI+] was stably inherited in a non-Mendelian fashion, but not eliminated upon the inactivation of Hsp104, unlike known [PSI+] elements. In vitro, non-Gln/Asn repeat domains formed amyloid fibres that were shorter and grew more slowly than did Gln/Asn-rich prion domains, while [PHI+] aggregates were smaller than [PSI+] aggregates in vivo. CONCLUSIONS: These findings suggest the existence of an alternative, Hsp104-independent pathway to replicate non-Gln/Asn variant Sup35 prion seeds.  相似文献   
17.
A case of multicentric malignant fibrous histiocytoma of the stomach and small intestine is reported. The patient was a 60-year-old man who had total gastrectomy under an impression of a gastric carcinoma. The resected stomach revealed a large polypoid mass in the antral portion at the greater curvature. Three months later, he developed ileus and an 80 cm segment of the jejunum was removed. It contained two polypoid masses identical to that seen in the stomach. The tumors showed, in addition to the characteristic light microscopic appearances, strong positivity for alpha-1-antitrypsin by an immunoperoxidase technique, indicating the diagnosis of malignant fibrous histiocytoma (MFH). Electron microscopic findings were also consistent with MFH. We believe that this is the first well-documented case of MFH arising from the stomach and small intestine, to the best of our knowledge.  相似文献   
18.
BACKGROUND: Inteins and group I introns found in prokaryotic and eukaryotic organisms occasionally behave as mobile genetic elements. During meiosis of the yeast Saccharomyces cerevisiae, the site-specific endonuclease encoded by VMA1 intein, VDE, triggers a single double-strand break (DSB) at an inteinless allele, leading to VMA1 intein homing. Besides the accumulating information on the in vitro activity of VDE, very little has been known about the molecular mechanism of intein homing in yeast nucleus. RESULTS: We developed an assay to detect the product of VMA1 intein homing in yeast genome. We analysed mutant phenotypes of RecA homologs, Rad51p and Dmc1p, and their interacting proteins, Rad54p and Tid1p, and found that they all play critical roles in intein inheritance. The absence of DSB end processing proteins, Sae2p and those in the Mre11-Rad50-Xrs2 complex, also causes partial reduction in homing efficiency. As with meiotic recombination, crossover events are frequently observed during intein homing. We also observed that the absence of premeiotic DNA replication caused by hydroxyurea (HU) or clb5delta clb6delta mutation reduces VDE-mediated DSBs. CONCLUSION: The repairing system working in intein homing shares molecular machinery with meiotic recombination induced by Spo11p. Moreover, like Spo11p-induced DNA cleavage, premeiotic DNA replication is a prerequisite for a VDE-induced DSB. VMA1 intein thus utilizes several host factors involved in meiotic and recombinational processes to spread its genetic information and guarantee its progeny through establishment of a parasitic relationship with the organism.  相似文献   
19.
It is still in doubt whether the standard-dose growth hormone (GH) used in Japan (0.5 IU/kg/week, 0.167 mg/kg/week) for growth hormone deficiency is effective for achieving significant adult height improvement in non-growth hormone deficient (non-GHD) short children. We compared the growth of GH-treated non-GHD short children with that of untreated short children to examine the effect of standard-dose GH treatment on non-GHD short children. GH treatment with recombinant human growth hormone (rhGH) was started before the age of 11 yr in 64 boys and 76 girls with non-GHD short stature registered at the Foundation for Growth Science who have now reached their adult height. In 119 untreated boys and 127 untreated girls whose height standard deviation score (SDS) was below –2 SD at the age of 6 yr, height growth was followed until 17 yr. Height SDS was significantly lower before GH treatment in the GH-treated group than at the age of 6 yr in the untreated group, in both sexes. Adult height and adult height SDS were significantly greater in the untreated group than in the GH-treated group, in both sexes, although the change in height SDS did not differ significantly. Height SDS was significantly lower before GH treatment in the GH-treated group than at the age of 6 yr in the untreated group, so 57 boys and 57 girls whose height SDS at the age of 6 yr in the untreated group closely matched the height SDS before GH treatment in the GH-treated group were chosen for comparison. Height SDS did not differ significantly between the GH-treated group before GH treatment and the untreated group at the age of 6 yr, nor were there differences between these subgroups in adult height, adult height SDS, or height SDS change, in either sex. The effect of GH treatment is reported to be dose-dependent and doses over 0.23 mg/kg/week are reported to be necessary to improve adult height in non-GHD short children. Currently, the GH dose is fixed at 0.175 mg/kg/week in Japan, and we expected to find, and indeed concluded, that ordinary GH treatment in Japanese, non-GHD short children does not improve adult height.  相似文献   
20.
Simple and rapid analysis of aristolochic acid (AA) in crude drugs and Kampo extracts using a solid-phase extraction method and HPLC-PDA analysis was investigated. Extraction of AA from samples was accomplished by adding methanol containing 1% ammonia. The addition of ammonia ionized the AA of acidic substances so that they adhered to an acrylamide copolymer of a strong anion exchange resin (Sep-Pak QMA) coupled to diol silica easily. Furthermore, a mixture of acetonitrile–water–phosphoric acid (75:25:2, v/v) was effective in isolating AA from its carrier. Since almost all interfering peaks originating from contaminants in crude drugs and Kampo extract formulations could be removed, a satisfactory HPLC chromatogram of AA was obtained. A good result was also obtained when Aristolochiaceae and crude drugs containing AA were tested. Particularly in the case of the medicinal parts of Asarum, several interfering peaks and a ghost peak detected near the AA peak were eliminated. The AA contents of two Kampo extract formulations, tokishigyakukagoshuyushokyoto and ryutanshakanto, were calculated by HPLC analysis. The AA content (the sum of AA-I and AA-II) was 1.25–6.13 mg per daily dose. From an additional recovery experiment for Kampo formulations, high recovery rates of AA were obtained. Neither LC/MS nor special instrumentation was necessary. Our results suggest that this simple, quick, and sensitive analytical method to detect AA in crude drugs and Kampo extract formulations would be valuable in safety inspections of AA in crude drugs and their products.  相似文献   
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