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91.
BACKGROUND:The high frequency of aneuploidy sperm raises concerns that there may be an increased incidence of aneuploid offspring in ICSI programmes. In order to assess the role that chromosome complement plays in normal and abnormal fertility, detailed molecular cytogenetic studies must be done on sperm samples from men with normal and abnormal fertility. METHODS: To understand more clearly the cytogenetic make-up of sperm from oligoasthenoteratozoospermic (OAT) patients, multi-colour fluorescence in situ hybridization was used to determine numerical chromosome abnormalities. RESULTS: Increased aneuploidy frequencies for chromosomes 13, 18, 21, X and Y were detected in sperm from OAT patients. The frequencies of diploidy also increased. There were no differences in non-disjunction at meiosis I compared to meiosis II. Sperm count inversely correlated with the frequencies of diploidy, aneuploidies for chromosomes 13 and 21 in OAT patients. Twenty-two cycles of ICSI and 18 embryo transfers were performed in 20 couples. Only three cases achieved successful pregnancies. CONCLUSIONS: A higher incidence of meiotic errors and lower sperm counts was found in sperm from OAT patients. 相似文献
92.
Zúñiga J Vargas-Alarcón G Osnaya N Martínez-Tripp S Rodríguez-Reyna TS Hernández-Martinez B Hesiquio R Hernández-Pacheco G Gamboa R Juárez F Salgado N Granados J 《Genes and immunity》1999,1(1):66-68
The major histocompatibility complex (MHC) genes are highly polymorphic and therefore have been useful in population genetics and disease association studies. We analyzed restriction fragment length polymorphism of HSP70-2 alleles in healthy unrelated Mestizo, Mazatecan and Nahua populations. Both Indian groups, Mazatecans and Nahuas, were in Hardy-Weinberg equilibrium, while Mestizos were in disequilibrium (chi 2 = 0.399; P < 0.05). The Mazatecan Indians presented a high frequency of BB homozygosity (17.35%) compared to Mestizos (5%) (P = 0.01). Mexican ethnic groups present differences in distribution of BB genotype. The low frequency of BB genotype in Mestizos may be the result of a negative selection process. 相似文献
93.
Platelet adhesion onto segmented polyurethane film surfaces modified by addition and crosslinking of PEO-containing block copolymers 总被引:8,自引:0,他引:8
Polyethylene oxide (PEO) surfaces were prepared by the addition of PEO-containing amphiphilic block copolymers as surface modifying additives and of dicumyl peroxide (DCP) as a crosslinking agent in segmented polyurethane (PU). PEO-polypropylene oxide-PEO triblock copolymers (Pluronics) with different PEO chain length (from 0 to 98) were used as the surface modifying additives. The PEO additives in the PU film were then crosslinked to be stably entrapped in the PU matrix. The crosslinking was done by free radicals produced from the decomposition of DCP in the film through heating (120 degrees C) or ultraviolet irradiation (254 nm). The surface properties of the PEO additive-entrapped PU films were investigated by the measurement of water contact angles and electron spectroscopy for chemical analysis. The bulk properties such as water absorption, long-term film stability, and tensile strength and elongation at break, were also investigated. It was observed that addition of a small amount (5 wt% based on PU) of the PEO additives resulted in a considerable change of surface characteristics. The PEO additives were stably entrapped in the PU films by crosslinking of them, without significant changes of bulk properties of the films. From the platelet adhesion test on the prepared PEO additive-containing film surfaces, it was observed that the platelet adhesion on the surfaces decreases with increase in PEO chain length of PEO additives. The film surface containing additive with long PEO chains (chain length of 98) was particularly effective in preventing platelet adhesion. The crosslinking of the PEO additives in PU films did not affect the behavior of platelet adhesion on the surfaces; the films with crosslinked PEO additives showed similar platelet adhesion on the surfaces to the films with uncrosslinked ones. 相似文献
94.
Forebrain heat shock protein 70 (HSP70) immunohistochemical reactivity was investigated in rats subjected to gamma knife irradiation focusing on the right caudate putamen nucleus. The forebrain sections of all experimental animals were processed with anti-HSP70 antiserum and then by avidin-biotin peroxidase complex immunohistochemistry after gamma ray irradiation with a dose of 100Gy and they each survived for different times (from 30 min to 30 days). Some neurons, glial cells, and endothelial cells were HSP70-like immunoreactivity (HSP70-LI) positive. HSP70-LI was mainly distributed in the target area of irradiation, as well as in non-target regions, e.g. the cortex, hippocampus, and hypothalamus, etc. The expression and change of HSP70-LI from 3 h to 30 days after irradiation followed the following rules: (1) Within 3 to 24 h, the dilated vessels with HSP70-LI endothelial cells were found at first, and a few lightly stained HSP70-LI neurons and glias were observed in the target and non-target regions; (2) In 3-7 days, darkly stained HSP70-LI neurons and glias were apparently increased and formed an expression peak. From 14 to 30 days, HSP70-LI cells were distinctly decreased and became weakly stained or negative. These results suggested that although the irradiation target of the gamma knife was localized, the response to irradiation occurred extensively. 相似文献
95.
The characteristic features of hamartoma in terms of discrepancies in mammographic and sonographic shapes of the mass were evaluated. We reviewed 16 pathologically proven breast hamartomas, which had undergone preoperative mammography and ultrasonography. All masses were analyzed according to ACR-BIRADS on mammography. On sonography, each mass was analyzed for size, shape, margin, internal echogenicity, and posterior acoustic enhancement. We also analyzed the echogenicity of halo, and compared the characteristic changes in the shape of hamartomas attributable to compression in mammograms and sonograms. The most common sites were at 12 o'clock in the right breast and 2 o'clock in the left. The most common mammographic findings of the hamartomas were a round shape (11/16), a circumscribed margin (13/16), internal fat densities (D4)(16/16) and radiolucent halos (14/16). The most common sonographic findings of the hamartomas were an oval shape (16/16), circumscribed margins (10/16), heterogeneous internal echogenicity (14/16), echogenic (7/16) or echolucent halos (5/16), and posterior enhancements (12/16). The characteristic feature of hamartomas was a change of the mammographic round shape mass into an elongated oval shape mass by sonography (11/11), suggesting the compressibility of hamartomas. Three of the hamartomas contained a pathologically proven internal calcification. The presence of a hamartoma was suggested by a change in a mammographic round mass with a radiolucent halo into an oval heterogeneous mass surrounded by an echogenic or echolucent halo on the sonogram. This characteristic difference between the mammographic and sonographic findings was attributed to the hamartoma compressibility, and was associated with the over-proliferation of fat containing mature normal breast tissue. 相似文献
96.
Dextran gel filtration (using Sephadex G-75 gel) with a continuous monitoring system was applied to the determination of the molecular weight and for fractionation of poly(L -histidine), poly[imino-1-(4-imidazolylmethyl)-2-oxoethylene], (PLH). PLH was eluted satisfactorily with a pH 2,35 buffer, whereas it was adsorbed to the gel with a pH 5,40 buffer. The weight-average and number-average molecular weights (Mw and Mn) were determined from the calibration plot of molecular weight, obtained with proteins, and corrected by the Smith method. A highly fractionated “monodisperse” PLH with Mw/Mn = 1,14 to 1,22 was obtained from PLH with Mw/Mn = 1,43 by the use of a pH 4,95 acetic acid/ammonium acetate buffer. 相似文献
97.
Projections from the hypothalamus and its adjacent areas to the posterior pituitary in the rat 总被引:3,自引:0,他引:3
Cholera toxin conjugated horseradish peroxidase was injected into the posterior pituitary and its afferents traced in 21 albino rats. The neuronal processes as well as the perikarya were elaborately displayed. The principal and retrochiasmatic supraoptic nuclei and the magnocellular paraventricular subnuclei were densely labelled. The accessory cell groups or nuclei labelled included: the medial preoptic and anterior hypothalamic areas, the anterior and posterior fornical nuclei, the lateral hypothalamic area, the nucleus circularis and nucleus of the forebrain bundle and hitherto unknown or not fully appreciated retrochiasmatic area, the dorsal accessory groups in an area between the stria medullaris and fornix, on the one hand, and the stria terminalis and internal capsule, on the other, and a well developed subependymalperiventricular zone. The medial preoptic nucleus, subfornical organ and organ vasculosum laminae terminalis were also weakly stained. Dendrites of the magnocellular paraventricular nucleus have been said by some to be largely confined to the subnuclei in which they lie. Immunohistochemical studies have proved that they extended beyond their nuclear confinement. The present study has found much wider extension of their dendritic fields. In fact, dendrites of the magnocellular neurosecretory cells in general were long and had a certain degree of directional bias. Several sites projecting to the posterior pituitary were closely related to the cerebrospinal fluid. Namely, the subependymal neuronal plexuses along the third ventricle and beneath the interventricular foramen, and the subpial dendritic plexuses of the supraoptic and retrochiasmatic supraoptic nuclei. Neurons were seen to squeeze in-between the ependymal cells, bringing themselves very close to the cerebrospinal fluid. No direct cerebrospinal fluid-contacting elements, either cell bodies or processes, however, could be ascertained. It is proposed that these plexuses may monitor changes in the cerebrospinal fluid. Besides the principal neurohypophysial tract the posterior pituitary was found in the present study to receive its afferents via two accessory fasciculi, one coursing in the medial forebrain bundle and the other running along the lateral wall of the infundibular recess subependymally. 相似文献
98.
In spite of the numerous reports indicating the presence of humoral immunosuppressive factors in cancer patients, only a few of these factors have been biochemically identified. Furthermore, their role as effective immunosuppressors in vivo remains to be established. Our laboratory has attempted to isolate and identify the major immunosuppressive factor in the malignant effusions derived from ovarian and lung cancer patients. We have previously demonstrated that the Mr 52,000 immunosuppressive factor isolated from the ascites fluid of an ovarian cancer patient inhibited T-dependent immune responses in vivo and in vitro including the inhibition of E-rosetting. Thus, this immunosuppressive factor was named "suppressive E-receptor" (SER). Our current study demonstrates that this SER factor purified from malignant effusions derived from ovarian, lung, or head and neck cancer patients had a common component which dissociated equally into Mr 38,000-42,000 and 17,000-19,000 moieties on sodium dodecyl sulfate-polyacrylamide gel electrophoresis under vigorous reducing conditions. Electroelution of these two components followed by a limited amino acid sequence determination revealed these two components to have N-terminal amino acid sequences identical to the beta and alpha 2 subunits of normal adult haptoglobin. Immunoelectrophoresis of SER using a polyclonal antiserum to neonatal cord blood demonstrated that SER, unlike normal haptoglobin, has slower electrophoretic mobility than the normal adult haptoglobin. Western blotting analysis of SER separated on sodium dodecyl sulfate-polyacrylamide gel electrophoresis under denaturing conditions failed to recognize a monoclonal antibody directed specifically to SER. However, this monoclonal antibody exclusively reacted with the SER separated by an analytical polyacrylamide gel electrophoresis gel under nondenaturing conditions while normal adult haptoglobins or purified but denatured haptoglobin obtained from the same malignant fluid as SER all failed to react with this antibody. Thus, SER appears to bear an additional epitope(s) that is absent in normal adult haptoglobin. Since the SER as well as the neonatal haptoglobin have at least 100 to 1000-fold more potent immunosuppressive activity than the normal adult haptoglobin, this additional epitope(s) present in SER may be responsible for the potent immunosuppressive property of SER. 相似文献
99.
Wu Shen吴慎 Ju Lian-cai鞠连才 Shao Hui-xun邵惠训Zhang Xi-tan张习坦 Meng Qing-hai孟庆海 andLi Xue-guang李学光 《中华医学杂志(英文版)》1986,99(5):387-392
A strain (named BJ-1) of hepatitis A virus (HAV)
causing cytopathic effects (CPE) has been isolated in
A549 cell cultures from a fecal specimen of an infant
with hepatitis A. Hepatitis A antigen (HAAg) w3s
detectable in about 50To of the cells by immunofluo-
rescence (IF) assay. The viral antigenicity was spe-
cifically identified by monoclonal anti-HAV and chim-
panzee reference antiserum to HAV (NIH). HAV
particles in crystal arraDgement were observed in cell
cytoplasm by electron microscopy in ultrathin sec
tions. The particles appeared both "empty" and
"full". It was observed that many 27-30 nm virtts
particles were aggregated by convalescent human he-
patitis A sera and chimpanzee HAV antisera observ-
ed by immune electron microscopic (IEM) ex-
amination. BJ-1 HAAg could be detected on day
34 after inoculation at the initial passage. The virus
titers increased and the virus replication cycle short-
ened with serial passages. The highest TCID 50
was 10-5/0.1 ml and the shortest replication cycle 2-3
days. IF kit consisting of BJ-1 HAV infected A549
coverslip culture and sheep fluorescence antibody to
human IgM were made to detect anti-HAV IgM.
Comparing the BJ-t IF with the Abbott EIA HAVAB-
M kit. the coincidence rate was 98.4% (246/250). 相似文献
100.
目的 调查黑龙江逊克县边疆俄罗斯民族村蜱携带斑点热群立克次体的调查.方法 采集2017年4-6月418只活蜱样本,利用PCR方法分别扩增斑点热群立克次体(SFGR)3种不同目的 基因的特异性片段,通过基因测序进一步鉴定.结果 在所有蜱中共检出斑点热群立克次体核酸阳性样本93例,经SFGR 3种不同目的 基因测序对比确定所有样本均属于同一种斑点热群立克次体,且为日本立克次体(Rickettsia japonica),感染率为22.25%(93/418).其中在全沟硬蜱中检测阳性样本62例,感染率为21.68% (62/286);在嗜群血蜱中检测到阳性样本31例,感染率为23.48%(31/132).结论 Rickettsia japonica是该地区主要蜱携带病原体,并存在潜在威胁人类健康的风险,应加强对黑龙江逊克县边疆俄罗斯民族村地区媒介蜱的防治防控. 相似文献