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61.
Vascular Ehlers–Danlos syndrome (vEDS) is a hereditary connective tissue disorder (HCTD) characterized by arterial dissection/aneurysm/rupture, sigmoid colon rupture, or uterine rupture. Diagnosis is confirmed by detecting heterozygous variants in COL3A1. This is the largest Asian case series and the first to apply an amplification-based next-generation sequencing through custom panels of causative genes for HCTDs, including a specific method of evaluating copy number variations. Among 429 patients with suspected HCTDs analyzed, 101 were suspected to have vEDS, and 33 of them (32.4%) were found to have COL3A1 variants. Two patients with a clinical diagnosis of Loeys–Dietz syndrome and/or familial thoracic aortic aneurysm and dissection were also found to have COL3A1 variants. Twenty cases (57.1%) had missense variants leading to glycine (Gly) substitutions in the triple helical domain, one (2.9%) had a missense variant leading to non-Gly substitution in this domain, eight (22.9%) had splice site alterations, three (8.6%) had nonsense variants, two (5.7%) had in-frame deletions, and one (2.9%) had a multi-exon deletion, including two deceased patients analyzed with formalin-fixed and paraffin-embedded samples. This is a clinically useful system to detect a wide spectrum of variants from various types of samples.  相似文献   
62.
Overexpression of P-glycoprotein (Pgp) in tumors is one of the major mechanisms which mediates the multidrug resistance (MDR) phenotype. To evaluate the prognostic significance of Pgp in breast cancer, Pgp expression was examined in paraffin-embedded tissue sections of 94 breast cancer specimens by immunohistochemistry. Tissue specimens were obtained by mastectomy without preoperative chemotherapy. UIC2 monoclonal antibody which recognizes an extracellular epitope of human Pgp was employed. Of the 94 breast cancer specimens, 35 (37.2%) were positive for Pgp expression. Pgp expression had no correlation with menopausal or hormone receptor status, axillary lymph node involvement or tumor size. However, a significant correlation was observed between Pgp expression and disease relapse (p = 0.0322). Pgp-positive patients showed a significantly shorter disease-free survival period than Pgp-negative patients by the Kaplan-Meier method (p = 0.0433). These results suggest that immunohistochemical detection of Pgp in breast cancer tissue may have prognostic value after radical operation.  相似文献   
63.
Interleukin-6 (IL-6) levels have been shown to correlate well with the magnitude of surgical stress. Serum IL-6 and plasma granulocytic elastase levels, 24 h after surgery, were determined in 12 patients who underwent open major surgery [MS group; esophageal carcinoma (n=5), gastric carcinoma (n=3), colorectal carcinoma (n=4) 5 patients who had open cholecystectomy [OC group] and 17 patients who had laparoscopic cholecystectomy [LC group]. IL-6 levels correlated significantly with the duration of surgery (r=0.685,P < 0.01) and with intraoperative blood loss (r=0.583,P < 0.02). However, there was no significant correlation between granulocytic elastase and the duration of surgery or blood loss. Plasma IL-6 levels in the LC group (21±3 pg/ml) were significantly lower than those in the OC group (47±5 pg/ml) and the MS group (186±36pg/ml) (P<0.05;P<0.01). However, there was no significant difference in granulocytic elastase levels between the LC group (318±8g/l), the OC group (360±130 gmg/ml), and the MS group (701±344 g/l). Increased IL-6 levels correlated well with increased duration of surgery. The lower IL-6 levels following laparoscopic cholecystectomy may therefore be indicative of lower surgical stress associated with laparoscopic cholecystectomy.  相似文献   
64.
A 51-year-old Japanese man who underwent a standard distal gastrectomy for cancer of the stomach developed abdominal pain when oral intake was commenced on the 6th postoperative day after an uneventful postoperative course. Complete obstruction of the jejunum led to a sudden deterioration in his general condition and a laparotomy was performed, revealing counterclockwise rotation of the mesenterium. The necrotic portion of the small intestine was removed, while 10 cm of the upper jejunum and 100 cm of the terminal ileum were preserved. His second postoperative course was uneventful apart from the development of intestinal hurry, which is now under medical control 9 months after his second laparotomy.  相似文献   
65.
Summary The cellular receptor for urokinase-type plasminogen activator (uPAR) in glioblastoma cell lines has been identified and found to be similar to the uPAR expressed by other tumor cell lines. Increased levels of uPAR have been found in primary malignant brain tumor tissues, especially highly malignant glioblastoma, and, to a lesser degree, in malignant astrocytomas, suggesting that this receptor might be involved in efficient activation of pro-uPA and confinement of uPA activity on the cell surface of invading brain tumors. The cell surface uPARs in gliomas could constitute an optimum environment for the generation and activity of plasmin, which is known to play a crucial role in the dissolution of the extracellular matrix during tumor cell invasion.In situ hybridization studies have shown that uPAR mRNA is expressed abundantly in tumor cells and is consistently present at the invasive edges of malignant gliomas. These results imply that uPAR is involved in plasmincatalyzed proteolysis during glioma invasion and that interference with the uPAuPAR interactions could constitute a novel approach for developing therapeutic strategies to counteract invasion of brain tumors.  相似文献   
66.
Mammary tumors of a newly isolated strain of Chinese wild mouse (JYG mouse) harbor exogenous mouse mammary tumor virus (MMTV). The complete nucleotide sequence of exogenous JYG-MMTV was determined on the proviral 5' long terminal repeat (LTR)(partial)-gag-pol-env-3' LTR (partial) fragment cloned into a plasmid vector and the cDNA sequence from JYG-MMTV producing cells. Similarly to the other MMTV species the LTR of JYG-MMTV contains an open reading frame (ORF). The amino acid sequence of the JYG-MMTV ORF resembles that of SW-MMTV (92% identity) and endogenous Mtv-7 (93% identity) especially at the C-terminal region. Thus, a functional similarity in T-cell receptor V beta recognition as a superantigen is implicated among these MMTV species. Analysis of the viral gag nucleotide sequence revealed that this gene is not disrupted by the bacterial insertion sequence IS1 or IS2, which have been reported to be present in the majority of the plasmids containing the gag region. Comparison of amino acid sequences of JYG-MMTV with those of BR6-MMTV showed that over 96% of the amino acids of gag, pol, protease and env products are identical. These results suggest the intact nature of the nucleotide sequence of the near full-length MMTV genome cloned in the plasmid.  相似文献   
67.
The delayed neurotoxic organophosphate, diisopropylfluorophosphate (DFP) binds with high affinity to membrane-bound proteins from chicken nerve tissues. The autoradiographic distribution of [3H]DFP binding sites in spinal cord sections of chicken showed higher concentrations of binding sites in gray matter than in white matter. In the cervical region, fairly high densities of [3H]DFP binding sites were found in laminae X and to a lesser extent, in the ventral horn gray matter. To identify the membrane-associated DFP-binding proteins, detergent-solubilized membranes were labeled widi 5-10nM [3H]DFP (10pmol/mg protein) for 70 min at 37°C. Gel-exclusion chromatography of the [3H]DFP-radiolabeled membranes indicated at least two major radioactive proteins with apparent molecular weights of 150-670 kDa and 40-129 kDa. Although we could not identify the high affinity DFP binding proteins, the autoradiographic experiments clearly demonstrated that the DFP binding proteins localized on gray matter of chicken spinal cord.  相似文献   
68.
The method for subtracting the initial image from the localization image was evaluated for radioimmunoscintigraphy of tumors with technetium-99m (Tc-99m) labeled antibodies. Monoclonal antibodies were parental mouse and mouse-human chimeric antibodies to carcinoembryonic antigen (CEA), designated F11-39 and ChF11-39, respectively, both of which have been found to discriminate CEA in tumor tissues from the CEA-related antigens. After reduction of the intrinsic disulfide bonds, these antibodies were labeled with Tc-99m. In vivo studies were performed on athymic nude mice bearing the human CEA-producing gastric carcinoma xenografts. Though biodistribution results showed selective and progressive accumulation of Tc-99m labeled antibodies at the tumor site, high radioactivity in blood was inappropriate for scintigraphic visualization of the tumors within a few hours. We examined the subtraction of the initial Tc-99m image from the Tc-99m localization image after a few hours. Subtracted images of the same count reflected the in vivo behavior of the Tc-99m radioactivity. The subtracted scintigrams revealed excellent tumor images with no significant extrarenal background. Visualization of the tumor site was dependent on antigen-specific binding and nonspecific exudation. These results demonstrate that a method of subtraction of the initial image may serve as a potentially useful diagnostic method for an abnormal site for agents with a low pharmacokinetic value.  相似文献   
69.
70.
Axonal and glial reactions to traumatic injury were compared between the caudal and rostral border of the lesion after freeze-injury to the C3 dorsal funiculus by attaching a liquid nitrogen-cooled copper probe to the dorsum of the rat spinal cord. The axonal and glial changes were examined up to 60 days postoperative by light and electron microscopy and immunohistochemistry for neurofilaments. Regenerative axonal changes and the appearance of numerous undifferentiated cells were found at the caudal border 7 days after cryoinjury. In contrast, such axonal and cellular reactions were scarce at the rostral border. Undifferentiated cells clearly manifested their phenotypes by differentiating into oligodendrocytes or astrocytes 11 days postinjury. The results indicated that glial cell reactions occurred in association with regenerative axonal changes at the proximal stump of the injured nerve fibers, suggesting that regenerating and demyelinated naked axons could be responsible for the appearance of the immature glial cells.  相似文献   
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