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941.
OBJECTIVE: To evaluate 2 methods of processing testicular tissue for the retrieval of viable sperm from men with nonobstructive azoospermia. STUDY DESIGN: Fresh testicular tissue was obtained from nonobstructive azoospermia patients using a biopsy needle. The specimens were divided into 2 fractions. All specimens were minced and immersed in human tubal fluid (HTF). The first fraction was filtered through a nylon filter and incubated for 3 hours. The supernatant was centrifuged, resuspended in HTF and analyzed. The second fraction was immediately vortexed for 5 minutes and filtered through a nylon filter. The supernatant was centrifuged, resuspended in HTF and analyzed. RESULTS: Spermatozoa were obtained in 13 of 24 cases (54.2%) using the vortex method and in 5 of 24 cases (20.8%) with the nylon filter method. CONCLUSION: The vortex mixing method may be a better option than the conventional method for processing testicular tissue for sperm collection.  相似文献   
942.
OBJECTIVE: Recent clinical studies suggested that intrapartum maternal fever is a strong independent risk factor for neonatal encephalopathy. With use of a well-studied rat model of neonatal hypoxic-ischemic encepalopathy, this study investigated the hypothesis that intraischemic hyperthermia accelerates and worsens brain injury in immature animals and examined whether apoptotic cell death machinery is involved in the underlying mechanisms. STUDY DESIGN: Seven-day-old rats underwent a combination of left common carotid artery ligation and exposure to 8% oxygen for 15 minutes (n = 32 rats). During the 15-minute hypoxic insult, body temperature was elevated to 40 degrees C in 16 animals (hyperthermic hypoxic insult group), and was maintained at 37 degrees C in 16 animals (normothermic hypoxic insult group). Then both groups were placed in the same chamber in a water bath at 37 degrees C for 24 hours and finally returned to the mothers. Caspase-3-like activity was assessed 36 hours after the hypoxic-ischemic insult. One week later, microtubule-associated protein-2 immunostaining was used to examine neuronal damage. RESULTS: Intraischemic hyperthermia was shown to activate the caspase-3 activity 36 hours after hypoxia-ischemia while caspase-3 was activated insignificantly in the normothermic hypoxic insult group at that time. The hyperthermic hypoxic insult group also showed a reduced microtubule-associated protein-2-positive area 7 days after hypoxia-ischemia compared with that in the normothermia group. CONCLUSION: Hyperthermia during hypoxia-ischemia makes the immature brain inordinately susceptible to hypoxic-ischemic insult and causes brain injury, even if hypoxic-ischemic insult is so mild that it causes no or little injury by itself. This effect may be mediated by the escalation of the apoptotic cell death pathway in the immature animal.  相似文献   
943.
Problem: Our previous studies have demonstrated that a subclass of soluble human leukocyte antigen-G1 protein (sub-sHLA-G1), that has 1 to 3 extra-cellular portion but lacks C-terminus of authentic soluble HLA-G1 secreted by trophoblasts, fine-tunes the release of cytokines from peripheral blood mononuclear cells (PBMCs) chiefly by counterbalancing membrane-bound HLA-G1 (mHLA-G1), and thereby may play a role in maintaining pregnancy. In this study, we investigated whether the presence of sHLA-G1 protein altered the release of cytokines from decidual mononuclear cells (DMCs) which are localized at the interface of feto–maternal interaction and whose cell population is completely different from PBMCs. Method of study: We cultured peripheral DMCs with either HLA-A and -B lacking B lymphoblast cell line (721.221 cells) or the cells transfected with mHLA-G1 (721.221-G1 cells) with or without sub-sHLA-G1. Cytokines concentrations in the culture media were determined by an enzyme-linked immunosorbent assay. Results: Regardless of the presence of mHLA-G1 expressing cells, the addition of the recombinant sub-sHLA-G1 protein in the DMC culture media decreased the amounts of tumor necrosis factor (TNF)- and interferon (IFN)-γ, with the release of IL-4 from DMCs being unchanged. Conclusion: The sub-sHLA-G1 protein modulates the release of cytokines from DMCs additively to mHLA-G1 expressing cells. In view of the distinct fetomaternal interaction during implantation, it appears that sHLA-G1 might play a role in the establishment of pregnancy by regulating cytokine release in concert with mHLA-G1.  相似文献   
944.
AIMS: Hyaline membrane (HM) in diffuse alveolar damage (DAD) pattern is frequently detected in the acute stage of interstitial pneumonia (IP). To determine the exact nature of HM, we investigated immunohistochemically 25 cases of HM-containing IP. METHODS: The cases examined using various kinds of antibodies were four cases associated with rheumatoid arthritis, five with usual interstitial pneumonia, two with dermatomyositis, five with viral infection, one case with progressive systemic sclerosis and eight cases caused by other agents. RESULTS: HM mostly reacted with antibodies to PE10 (SP-A), Factor VIII, KL-6 and EMA and, interestingly, stained for AE1/AE3, CK19, and Hup-1 in some cases, but was negative for PTAH staining. However, the immunoreactivities of HM varied even within the same disease or section. CONCLUSIONS: The immunohistochemical heterogeneity of HM suggests that HM may be formed by different mechanisms in various types of IP. Our findings also suggest that the main components of HM are derived from alveolar epithelial cells and their proteins, some including cytoplasmic element of CK19, and also from serum factors, but not fibrin. The immunohistochemical characteristics of HM in DAD pattern will aid understanding of the significance of HM formation in IP.  相似文献   
945.
A 64-year-old patient with mesenchymal chondrosarcoma of the temporal bone is described. CT and MRI showed an extensive mass with calcification involving the temporal bone and extending into the middle cranial fossa and nasopharynx. The tumor was ill-defined from surrounding normal bone, and a subtotal petrosectomy was carried out. The nasopharyngeal extension was removed secondarily using an endoscope. The clinical and diagnostic aspects and management of this rare lesion are discussed.  相似文献   
946.
Purpose: Evaluation of vascular endothelial growth factor (VEGF) concentrations of follicular fluid (FF) in accordance with an ovarian stimulation protocol and ovarian response. Methods: The subjects of this study were 38 patients undergoing IVF-ET in our hospital. They were divided into three groups according to ovarian stimulation protocols; Group 1: hMG cycles (n = 19), Group 2: clomiphene citrate cycles (n = 10), Group 3: natural cycles (n = 9). They reclassified into three groups according to the number of oocytes harvested. VEGF concentration was measured in FF, employing ELISAs. Results: Group 1 shows lower VEGF concentrations in FF than Group 2 or Group 3. Excluding high responders from Group 1, no difference was found among these three groups. As for the reclassified groups, group of highest number of oocytes havested showed lowest VEGF concentrations in FF. Conclusions: VEGF concentrations in FF might negatively correlate with the number of follicles, irrespective of the ovulation induction protocol.  相似文献   
947.
OBJECTIVE: In 2001, an estimated 800000 children were newly infected with HIV, almost all through mother-to-child transmission (MCTC), and 90% of these children were born in Africa. In such resource-poor settings, cheaper and more easily administered antiretroviral drugs should be available for use. Mass treatment of an intrapartum and neonatal single dose of nevirapine regimen has been suggested as an effective strategy to prevent MCTC, yet this strategy has never been conducted in clinical trials. By discussing the advantages and disadvantages of it, we analyze the possibility of implementing this regimen. METHODS: We reviewed public health strategies to prevent MCTC in resource-poor settings, and discuss whether or not mass treatment of an intrapartum and neonatal single dose of nevirapine regimen can be recommended as one therapy in sub-Saharan Africa due to its simplicity of distribution and use, long-term efficacy, and cost-effectiveness. RESULT: Recent studies in Uganda showed the high efficacy and cost-effectiveness of a single dose of nevirapine only to HIV/AIDS-positive pregnant women. The characteristics of nevirapine also meet the requirements of mass treatment. Mass treatment of nevirapine would increase access to antiretroviral drugs among pregnant women because they can access nevirapine without volunteer counseling and testing, which 31% of pregnant women in developing countries refused to accept due to the fear of stigmatization. No serious adverse effects or drug resistance to this regimen were reported through the studies in Uganda. CONCLUSION: Mass treatment of a single-dose nevirapine can be recommended as one alternative therapy, and further research is recommended to obtain more information about the efficacy, side-effects, drug resistance, and compliance of this strategy.  相似文献   
948.
BACKGROUND: A strong mutator mutation, dnaE173, leads to a Glu612 --> Lys amino acid change in the alpha subunit of Escherichia coli DNA polymerase III (PolIII) holoenzyme and abolishes the proofreading function of the replicative enzyme without affecting the 3' --> 5' exonuclease activity of the epsilon subunit. The dnaE173 mutator is unique in its ability to induce sequence-substitution mutations, suggesting that an unknown function of the alpha subunit is hampered by the dnaE173 mutation. RESULTS: A PolIII holoenzyme reconstituted from dnaE173 PolIII* (DNA polymerase III holoenzyme lacking the beta clamp subunit) and the beta subunit showed a strong resistance to replication-pausing on the template DNA and readily promoted strand-displacement DNA synthesis. Unlike wild-type PolIII*, dnaE173 PolIII* was able to catalyse highly processive DNA synthesis without the aid of the beta-clamp subunit. The rate of chain elongation by the dnaE173 holoenzyme was reduced to one-third of that determined for the wild-type enzyme. In contrast, an exonuclease-deficient PolIII holoenzyme was vastly prone to pausing, but had the same rate of chain elongation as the wild-type. CONCLUSIONS: The hyper-processivity and slower DNA chain elongation rate of the dnaE173 holoenzyme are distinct effects caused by the dnaE173 mutation and are likely to be involved in the sequence-substitution mutagenesis. A link between the proofreading and chain elongation processes was suggested.  相似文献   
949.
950.
This clinical report describes the fabrication of a fixed partial denture, supported and retained by implants, for a patient with unfavorable tongue movement caused by movable grafted skin on the floor of the mouth after surgical reconstruction of the mandible. The neutral zone technique was used, and successful results were obtained.  相似文献   
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