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71.
The in vitro activity of daptomycin-metronidazole combinations against mixed cultures of gram-positive facultative cocci and strains of theBacteroides fragilis group was investigated. Metronidazole did not influence the high activity of daptomycin against strains ofStaphylococcus aureus, Staphylococcus epidermidis andEnterococcus faecalis in the absence or presence of the co-culturedBacteroides strains. In contrast, theEnterococcus faecalis isolates protected the co-culturedBacteroides strains against the killing effect of metronidazole, even at a concentration four- or eightfold the MIC of metronidazole. Killing curve experiments confirmed this protective effect of different isolates ofEnterococcus faecalis.  相似文献   
72.
The analysis of seven Y-chromosome-specific microsatellite loci revealed a high level of polymorphism in two closely related human populations (Dutch, n = 89, and German, n = 70). Four of these loci were found to generate at least 77 different haplotypes, only 15 of which were shared by the two populations. These results demonstrate that highly informative PCR-based DNA typing of the Y chromosome is now feasible. Assuming a stepwise mutation model, a network comprising all minimum spanning evolutionary trees connecting the haplotypes was constructed. Analysis of molecular variance based upon this network indicated that the within-population heterogeneity with respect to haplotype descent was significantly smaller than the between-population heterogeneity, suggesting that males were more closely related to males from their own population as opposed to males from the other population. These findings suggest that Y-chromosomal microsatellites might be very useful not only for forensic purposes but also in association studies of multifactorial traits, allowing the characterization of the level of genetic distinctiveness of supposedly inbred or isolated populations and discrimination even between closely related populations.   相似文献   
73.
The effects of vitamin A were studied on the basal and maximal gastric secretory responses of 12 patients; and on healing in 60 patients with chronic gastric ulcer. The effect of vitamin A on ulcer healing was evaluated by a multiclinical, multicentre, randomized, prospective study in which the patients were divided into three groups. In group A the patients were treated with antacids only; in group B the patients were given antacids plus vitamin A (in doses of 3 X 50.000 U orally); and in group C the patients received antacids, vitamin A plus cyproheptadine (in doses of 3 X 4 mg orally). The treatment lasted four weeks. At the beginning and the end of treatment endoscopies were performed and ulcer sizes were measured planimetrically. Various other parameters such as ulcer index, antacid consumption and laboratory parameters were also evaluated during the four-week treatment. It was observed that: (i) vitamin A (given in doses of 100.000 U i.m.) decreased neither basal nor maximal gastric secretory responses; (ii) the number of patients with completely healed gastric ulcer was significantly higher (P less than 0.05) in groups B and C than in group A; (iii) the extent of ulcer reduction was significantly higher (P less than 0.01) in groups B and C than in group A; (iv) no significant changes were observed in ulcer index and antacid consumption during the four-week treatment in the different groups of patients; (v) the reduction of ulcer size was significantly greater (P less than 0.01) in the group treated with antacids plus vitamin A than in the group treated with antacids only, at two weeks of treatment.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
74.
This study aims to investigate whether the immunohistochemical levels of expression of galectin-3 and the macrophage migration inhibitory factor (MIF) are associated with prognostic values in human colorectal tumors. This was performed on 99 specimens including 69 colorectal tumors (17 Dukes A, 19 Dukes B, 15 Dukes C and 18 metastatic tumors that we labeled as D), 10 hepatic metastases from colorectal cancers and 20 normal specimens (biopsies). The immunohistochemical levels of expression of MIF and galectin-3 were quantified on routine histological slides by means of computer-assisted microscopy. Separate analyses were performed on epithelial and connective tissue. The levels of expression of both MIF and galectin-3 were very significantly higher in epithelial tumor tissue when compared with normal epithelial specimens. A positive and significant correlation between MIF and galectin-3 expression was evidenced in connective tumor tissue, and in particular in the cases associated with short survival periods (less than 5 years). In the case of the Dukes A or B tumors, we established two new prognostic groups (labeled I and II) on the basis of the levels of galectin-3 expression measured in the tumor epithelium. In the case of the Dukes C or D tumors, we established two other prognostic groups (labeled III and IV) on the basis of the levels of MIF expression measured in the connective tissue. Kaplan-Meyer analyses confirmed the additional prognostic values (as compared with conventional clinical staging) given by this new classification (groups I to IV). They show that the Dukes A or B tumors characterized by low levels of galectin-3 expression in the tumor epithelium are associated with significantly better prognoses than those characterized by high levels. In addition, the Dukes C or D tumors characterized by high levels of MIF expression in the connective tumor tissue are associated with significantly better prognoses than those characterized by low levels. In conclusions, MIF and galectin-3 expression levels in colorectal tumors are related to their levels of biological aggressiveness. These markers could be used to identify patients at risk, for whom more aggressive adjuvant therapy seems to be indicated.  相似文献   
75.
N-(2-mercaptoethyl)-lt3-diaminopropane (WR1065) protects againstradiation-induced cell killing and mutagenesis at the hypoxanthine-guaninephosphoribosyl transferase (HGPRT) locus in V79 Chinese hamsterhing fibroblast cells. At a concentration of 4 mM, WR1065 wasfound to be effective in protecting against radiation-inducedcell lethality only if present during irradiation, e.g., a dosemodification factor (DMF) of 1.9. No protective effect was observedif the protector was added within 5 min after irradiation or3 h later, e.g., DMFs of 1.0 and 1.1, respectively. The effectof WR1065 on radiation-induced mutation, expressed as resistanceto the cytotoxic purine analogue 6-thioguanine (HGPRT), wasalso investigated. In contrast to the treatment-schedule dependencefor protection by WR1065 against cell killing, this agent waseffective in reducing radiation-induced mutations regardlessof when it was administered. Following a dose of 10 Gy of 60Co-rays, the mutation frequencies observed per 106 survivors were77 ± 8, 27 ± 6, 42 ± 7, and 42 ±7 for radiation only, and WR1065 present during, immediatelyafter, or 3 h after irradiation. These data suggest that althougha segment of radiation-induced damage leading to reproductivedeath cannot be modulated through the postirradiation actionof WR1065, processes leading to the fixation of gross geneticdamage and mutation induction in surviving cells can be effectivelyaltered and interfered with leading to a marked reduction inmutation frequency.  相似文献   
76.
Patients with chronic myelofibrosis often suffer from osteosclerosis, which is associated with bone pain and may lead to bone marrow failure. The pathogenesis of myelofibrosis is linked to aberrant megakaryocyte development and function. Null and loss-of-function mutations in MPIG6B, which codes for the inhibitory heparan sulfate receptor G6b-B, result in severe macrothrombocytopenia, large megakaryocyte clusters, and focal primary myelofibrosis in mice and humans. We investigated the development of osteosclerosis in Mpig6b null (Mpig6b−/−) mice. Although male and female Mpig6b−/− mice presented with elevated bone marrow megakaryocyte number and macrothrombocytopenia, female Mpig6b−/− mice developed progressive splenomegaly starting at 8 weeks of age. Micro–computed tomography (μCT) of femurs showed that female Mpig6b−/− mice had increased cortical thickness and reduced bone marrow area starting at 8 weeks of age and developed occlusion of the medullary cavity by trabeculae by 16 weeks of age. In contrast, male Mpig6b−/− mice developed only a small number of trabeculae in the medullary cavity at the proximal diaphysis and demonstrated a temporary decrease in bone volume fraction and trabecular thickness at 16 weeks. Ovariectomy of 10-week-old female Mpig6b−/− mice prevented the development of medullary cavity osteosclerosis, whereas orchiectomy of male Mpig6b−/− mice did not exacerbate their disease. Importantly, ovariectomized female Mpig6b−/− mice also demonstrated improvement in spleen weight compared to sham-operated Mpig6b−/− mice, establishing estrogen as a contributing factor to the severity of the megakaryocyte-driven osteosclerosis. © 2021 American Society for Bone and Mineral Research (ASBMR).  相似文献   
77.
Total elbow arthroplasty as a treatment option for open elbow fracture is relatively rare described. We reported a 39 years old polytrauma patient with complex open elbow fracture (Gustilo-Anderson type IIIB). The patient presented with large soft tissues defect on dorsal part of the left elbow, ulnar palsy due to the irreparable loss of the ulnar nerve, distal triceps loss due to the complete loss of the olecranon, loss of both humeral condyles with collateral ligaments and complex elbow instability. Only few similar cases have been published. Reconstructive surgery included repetitive radical debridement, irrigation, vacuum assisted closure system therapy, external fixation, coverage of the soft tissue defect with fascia ecutaneous flap from the forearm. Four months after the injury, total elbow arthroplasty with autologous bone graft (from the proximal radius) inserted in the ulnar component, was performed. At 3 years postoperatively, the patient is able to perform an active flexion from 0 to 110 with full pronosupination. Only passive extension is allowed. The ulnar neuropathy is persistent. Patient has no signs of infection or loosening of the prosthesis.  相似文献   
78.
BackgroundTo evaluate whether stone extraction with a loop ureteral catheter (LUC) in distal ureteral stones is associated with a higher frequency of ureteral strictures compared to treatment with primary ureteroscopic stone removal (p-URS) or ureteroscopic laser lithotripsy (l-URS).MethodsFive hundred and forty-seven consecutive patients were primarily endourologically treated for distal ureteral stones in our department between 2005 and 2019 and included in the study protocol. Data was retrospectively obtained from the patients’ charts and medical reports as well as from office-based urologists. Data analysis was performed using Fisher’s exact test, Mann-Whitney test or Student’s t-test as appropriate. A level of P<0.05 was assigned statistical significance.ResultsFour hundred and twelve patients were treated by URS (p-URS n=304, l-URS n=108) and another 135 by LUC stone extraction. Median follow-up was 41 [2–159] months. There was no difference between the groups concerning age, gender, proportion of patients with ureteral stenting, operating time, hospitalization or readmission rates. The number of ureteric strictures was small in all procedures [n=3 (1.0%) in p-URS, n=2 (1.9%) in l-URS and n=2 (1.5%) in LUC] and there was no difference between the groups concerning this serious complication (p-URS vs. LUC: P=0.6465; l-URS vs. LUC: P=0.9999).ConclusionsIn small distal stones, LUC stone extraction still is an alternative to URS procedures in stone management with comparable results concerning postinterventional ureteral strictures. In experienced hands, it still has its value in accurately selected patients.  相似文献   
79.
Members of the filamentous fungal genus Fusarium are among the agents most frequently causing keratomycosis in humans. Fusarium keratitis is most common among agricultural workers in geographical regions with hot, humid, tropical or semi-tropical climates, but can occur more rarely in countries with temperate climates, such as Hungary. Keratitis is usually treated with a topical antifungal agent, sometimes in combination with sub-conjunctival injections and/or antimycotic agents, but therapeutic keratoplasty may be needed for patients whose corneal infection does not resolve. Early and accurate diagnosis, coupled with appropriate antifungal therapy, is crucial for improving the chances of complete recovery.  相似文献   
80.
Intracytoplasmic sperm injection in the mouse   总被引:9,自引:0,他引:9  
Intracytoplasmic sperm injection (ICSI) into mouse oocytes involvesa very low survival rate. This study was designed to determinewhy ICSI frequently fails in mice. Metaphase II oocytes wereobtained from superovulated 4–6 week old F1 hybrid mice.Spermatozoa were retrieved from the epididymis of 12–14week old F1 hybrid mice. The spiked microinjection pipette usedto inject a spermatozoon into the ooplasm had outer and innerdiameters of 10 and 8 µm respectively. The oocytes usedin the first part of the study were not activated (group 1).Some oocytes were incubated with calcium ionophore for 5 min(group 2). The injected oocytes were evaluated 6, 20, 48 and72 h after injection. A total of 143 eggs in each group underwentICSI. In group 1, sperm heads escaped into the perivitellinespace. In all, 63 (47%) of the remaining oocytes were damagedduring the injection or had degenerated by the first evaluation.The survival rate was 53%, but fertilization did not occur.In group 2, 31 oocytes (22%) were damaged during microinjectionor soon degenerated. Two oocytes underwent accidental subzonalinsemination. Six oocytes were fertilized (4.2%) among the 78%of survivors. After injection, the sperm tail was found in thecytoplasm (27 and 31% in groups 1 and 2 respectively), the perivitellinespace (45% in both groups) or protruding through the zona pellucida(28 and 23% respectively). More oocytes degenerated when thetail remained in the cytoplasm, i.e. 78% in group 1 and 36%in group 2.  相似文献   
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