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101.
Overexpression of the TCL1 oncogene has been shown to play a causative role in T cell leukemias of humans and mice. The characterization of Tcl1-deficient mice in these studies indicates an important developmental role for Tcl1 in early embryogenesis. In wild-type embryos, Tcl1 is abundant in the first three mitotic cycles, during which it shuttles between nuclei and the embryo cortical regions in a cell-cycle-dependent fashion. The absence of this protein in early embryogenesis results in reduced fertility of female mice. The present studies elucidate the mechanism responsible for the reduced female fertility through analysis of the oogenesis stages and early embryo development in Tcl1-deficient mice. Even though Tcl1(-/-) females display normal oogenesis and rates of oocyte maturation/ovulation and fertilization, the lack of maternally derived Tcl1 impairs the embryo's ability to undergo normal cleavage and develop to the morula stage, especially under in vitro culture conditions. Beyond this crisis point, differentiative traits of zygotic genome activation and embryo compaction can take place normally. In contrast with this unanticipated role in early embryogenesis, we observed an overexpression of TCL1 in human seminomas. This finding suggests that TCL1 dysregulation could contribute to the development of this germinal cell cancer as well as lymphoid malignancies.  相似文献   
102.
Intratracheal instillation of bleomycin in hamsters initiates a series of events that mimic human interstitial pulmonary fibrosis. Because glycosaminoglycans and particularly hyaluronan (hyaluronic acid, HA), may play an important role in the extracellular matrix response to early injury and subsequent fibrosis, this study was undertaken to define the early time course of changes in HA and hyaluronidase. Hamsters were given either 1 unit bleomycin sulfate in 0.2 ml saline or 0.2 ml saline (control), and randomly selected animals from both groups were killed at Days 3, 5, 6, 7, 9, and 17. Glycosaminoglycan fractions prepared from lung tissue of individual animals were analyzed for HA. The maximal HA content was reached 6 days after instillation of bleomycin and was 14.6-fold the normal value. The weight of injured lungs was 2.3-fold the control value. Thus, the increase in HA content was 30-fold. By Day 7 the HA content had dropped sharply. It then declined gradually to approximately double control values at Day 17. The specific activity of lysosomal hyaluronidase was the same in bleomycin-treated lungs and control lungs. Total units of the enzyme were increased in injured lungs, even at the time of maximal HA content, indicating active turnover of HA. The maximal HA content occurs prior to the rise in collagen and elastin biosynthesis. This observation in addition to the magnitude of the increase and its abrupt decline suggest that HA may be an important initiating factor for pathologic changes in lung extracellular matrix components.  相似文献   
103.
Colorectal cancer (CRC) is one of the most prevalent cancers and the second leading cause of cancer-related deaths worldwide. The treatment strategy employed in CRC patients is becoming highly dependent on molecular characteristics present at diagnosis and during treatment. Liquid biopsy is an emerging field in the management of this cancer, and its relevance as a potential diagnostic, prognostic, monitoring, and therapeutic tool makes it a viable strategy in the clinical management of CRC patients. Liquid biopsy also has certain limitations, but these limitations seem to be at the reach of near-future technological development. In this letter, we focus on the clinical perspectives of liquid biopsy in CRC with particular regard to the various biomarkers recently identified that have been shown to be potentially useful in multiple aspects of early stage or metastatic CRC.  相似文献   
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Congenital bilateral absence of vas deferens (CBAVD) is a manifestation of the mildest form of cystic fibrosis (CF) and is characterized by obstructive azoospermia in otherwise healthy patients. Owing to the availability of assisted reproductive technology, CBAVD patients can father children. These fathers are at risk of transmitting a mutated allele of the CF transmembrane conductance regulator (CFTR) gene, responsible for CF, to their offspring. The identification of mutations in both CFTR alleles in CBAVD patients is a crucial requirement for calculating the risk of producing a child with full-blown CF if the female partner is a healthy CF carrier. However, in the majority of CBAVD patients, conventional mutation screening is not able to detect mutations in both CFTR alleles, and this difficulty hampers the execution of correct genetic counselling. To obtain information about the most represented CFTR mutations in CBAVD patients, we analysed 23 CBAVD patients, 15 of whom had a single CFTR mutation after screening for 36 mutations and the 5T allele. The search for the second CFTR mutation in these cases was performed by using a triplex approach: (i) first, a reverse dot-blot analysis was performed to detect mutations with regional impact; (ii) next, multiple ligation-dependent probe amplification assays were conducted to search for large rearrangements; and (iii) finally, denaturing high-performance liquid chromatography was used to search for point mutations in the entire coding region. Using these approaches, the second CFTR mutation was detected in six patients, which increased the final detection rate to 60.8%.  相似文献   
106.

Aim

CDH1 germline alterations occur in about 40% of hereditary diffuse gastric cancer (HDGC) families. CDH1 germline mutations are also documented in few early onset diffuse gastric cancer patients (EODGC) without family history, but the real frequency in this setting in unknown. In these patients, the advanced stage at the time of diagnosis remains a clinical burden due to the poor long term survival.

Methods

The entire coding region and exon flanking sequences of the CDH1 gene was analysed by direct sequencing in 21 EODGC patients aged ?50 years. The potential deleterious nature for a new CDH1 missense variant was assessed by cell-cell aggregation and invasion assays. Somatic CDH1 mutation, loss of heterozigosity (LOH) and promoter hypermethylation was explored in the tumour from one CDH1 germline mutation carrier.

Results

Two novel CDH1 germline variants were identified in 21 EODGC cases, c.670C>T and -63C>A. Functional analysis of the c.670C>T missense variant classified this mutation as non-pathogenic. The analysis of CDH1 somatic second hits failed to demonstrate E-cadherin structural and epigenetic alterations in the tumour sample.

Conclusion

Data from the present work and a systematic review of the literature revealed that CDH1 germline mutations occurred in 7.2% of EOGC patients invariably with diffuse of mixed histology. From these, proved CDH1 mutation pathogenicity has been assigned only to 2.3% of the cases who were recurrently diagnosed before 35 years old. Germline CDH1 mutation remain the only germline genetic defect described in this type of patients and CDH1 mutation screening should be recommended for patients with these characteristics.  相似文献   
107.
Peritoneal carcinomatosis (PC) had long been regarded as a terminal disease, characterized by a very poor survival and worth treating with palliative therapy. A new strategy combining maximal surgery (cytoreductive surgery, CRS), with maximal regional chemotherapy (hyperthermic intraperitoneal chemotherapy, HIPEC), has been proposed to treat PC, resulting in long-term survival rates in selected patients. The emerging trend is to view localised peritoneal carcinomatosis, in the absence of other metastases, as a regional metastatic disease that is amenable to locoregional therapy. In spite of the need for more high quality studies, many international experts now agree that the use of this new strategy is a gold standard for treating selected patients with PC with the intent of curing. The best results are achieved in patients with limited disease who have completed macroscopic tumor removal. To offer a comprehensive review, we summarized the present status and possible future progress of this treatment modality, in particular outlining its rationale, current practice and general outcome.  相似文献   
108.
109.
110.
We present the case of a male patient who needed surgery for a large undefined submandibular schwannoma and a small contralateral thyroid carcinoma associated with cervical lymph nodes of a dubious nature. During the operative procedure all the pathological conditions were resolved, with some remarkable surprises. A non-functioning parathyroid adenoma was found and removed. A fairly unusual anatomical complication was also detected with regard to the right inferior laryngeal nerve, i.e. an anastomotic branch connecting the main trunk to the vagus nerve.  相似文献   
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