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51.
Evidence that the shift of services from secondary to primary care is creating extra work for GPs is limited. A study showed that it is possible to quantify additional workload for GPs, but that certain aspects, such as measuring the time input, remain problematic. Future research needs to agree workload definitions, employ sensitive measures other than consultation rates, and distinguish between workload in practices and that of individual practitioners.  相似文献   
52.
Previous studies have shown that hyperthermia is an effective modulator of cis-diamminedichloroplatinum(II) (CDDP) cytotoxicity. We have examined the potential of inhibitors of the arachidonic acid metabolism to increase the antitumor activity of CDDP and hyperthermia. Sulindac and diflunisal are cyclooxygenase inhibiting non-steroidal anti-inflammatory drugs (NSAIDS) and phenidone is a lipoxygenase inhibitor. Using the FSaIIC in vivo-in vitro excision assay, neither five daily injections of sulindac nor diflunisal added to the killing of FSaIIC cells achieved by one injection of CDDP at normal temperature. When the i.p. injection of CDDP and the NSAIDS were followed immediately by hyperthermia treatment to the tumor bearing limb at 43-degrees-C for 30 min, the cell killing achieved was increased by 2-3-fold by diflunisal over the dose range of CDDP examined but was unaffected by sulindac. Phenidone did not alter the cell killing achieved by CDDP at normal temperature or when the CDDP was followed by local hyperthermia, but use of a combination of sulindac or diflunisal plus phenidone increased the cell killing achieved by 2-10-fold when used with local hyperthermia over the dose range of CDDP tested. In tumor growth delay (TGD) studies, addition of five daily injections of sulindac, diflunisal or phenidone did not increase the TGD achieved by CDDP at normal temperature and neither diflunisal nor phenidone markedly increased the TGD produced by CDDP in conjunction with local hyperthermia, but the administration of sulindac resulted in about a 3-fold increase in TGD as did use of a combination of diflunisal or sulindac plus phenidone. These results indicate that inhibitors of arachidonic acid metabolism can increase the cell killing and the tumor growth delay produced by CDDP plus local hyperthermia.  相似文献   
53.
EMT-6/Parent and EMT-6/CDDP and EMT-6/CTX in vivo alkylating agent resistant cells were grown as spheroids or as monolayers and their response to cis-diamminedichloroplatinum(II) or 4-hydroperoxycyclophosphamide exposure for 1 h alone or in combination with TNP-470 or SR-4233 was determined. When grown as spheroids, each of the three cell lines were less responsive to cis-diamminedichloroplatinum(II) and 4-hydroperoxycyclophosphamide exposure than when the cells were grown and drug-treated in monolayer. The hypoxic cell selective cytotoxic agent SR-4233 was additive in cytotoxicity with the antitumor alkylating agents in both the monolayer and spheroid cultures as determined by isobologram analysis. The antiangiogenic agent TNP-470 was synergistic in cytotoxicity in combination with cis-diammedichloroplatinum in each of the three cell lines when the cells were grown in monolayer and was additive in cytotoxicity with cis-diamminedichloroplatinum(II) when the cells were grown as spheroids. The combination of TNP-470 and 4-hydroperoxycyclophosphamide resulted in additive cytotoxicity toward both monolayer cultures and spheroids. Thus, co-exposure with TNP-470 or SR-4233 increased the cytotoxicity of the antitumor alkylating agents in both the parental and drug resistant cells grown as monolayers or spheroids.  相似文献   
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DNA topoisomerase I (topo I) is the molecular target of the camptothecin group of antitumor drugs. Laboratory studies have indicated that cells sensitive to these drugs contain elevated levels of topo I. In this study, we immunostained 49 cases of transitional cell carcinoma from the urinary bladder with a monoclonal antibody directed against human topo I. We found elevated expression of the enzyme in 77% (38 of 49). This included three of six grade I tumors (50%), 9 of 15 grade II tumors (60%), 14 of 15 grade III tumors (93%) and 12 of 13 grade IV tumors (92%). Because the number of cycling cells in a tumor also may be an important determinant of topo I drug response, a proliferation index (topo II-alpha) also was performed for each case. The average topo II-alpha index of grade I tumors was 7.5 x 3.8; for grade II tumors, 20.1+/-10.5; for grade III tumors, 40.3 x 8.2; and for grade IV tumors, 50.5+/-13.0. Because a functional p53 tumor suppressor gene may be necessary for anticancer drug response, we also evaluated our cases for alteration in p53 function. Mutations in the p53 tumor suppressor gene, estimated by immunohistochemical staining, were common, occurring in 23 of 49 cases (47%). The number of cases with elevated topo I, a large growth fraction, and a functional p53 tumor suppressor gene was 4 of 49 (8%). Our results suggest that a small population of patients with transitional cell carcinoma of the urinary bladder may have tumors with molecular features suggesting responsiveness to the new anticancer drugs targeting topo I.  相似文献   
56.
This pilot study's aim was to determine, using magnetic resonance imaging (MRI), if and to what extent asymptomatic intracranial hemorrhage occurs in normal term neonates after uncomplicated vaginal deliveries. Eight normal, term, vaginally delivered infants and three cesarean-section deliveries used as controls underwent cranial MRI. No sedation was administered. Small subdural hematomas of the falx cerebri or tentorium cerebelli were found in half of those with an uneventful vaginal delivery. Pediatric follow-up, on average 3.9 years after the MRI study was performed, demonstrated normal growth and development. It appears that more data is needed to confirm the observation that the intracranial hemorrhages described should not be considered the etiology for neurologic abnormalities present in symptomatic neonates.  相似文献   
57.
Preliminary pharmacologic evidence suggests that tiagabine, a new presynaptic gamma-aminobutyric acid-uptake inhibitor developed as an antiepileptic drug, may also relieve spasticity. This pilot study assessed the drug's efficacy in 14 children with congenital or acquired spastic quadriplegia and concomitant intractable epilepsy refractory to treatment with multiple antiepileptic drugs. The primary outcome variable was change in motor function; the secondary outcome was change in seizure frequency. Tiagabine was initiated at 0.1-0.2 mg/kg/day and then gradually titrated upward until seizures ceased, adverse effects supervened, or the maximum dose of 1.1 mg/kg/day was reached. When a modified Ashworth scale was used to assess motor function, a mean improvement of approximately 50% was observed. Common findings included improved tone, strength, coordination, range of motion, and relaxation of extremities, with less ataxia and wobbling. Mean reduction in seizure frequency was 50-74%. Randomized, double-blind controlled studies are needed to confirm the suggested efficacy of tiagabine in relieving chronic spasticity in children with neurodevelopmental disorders.  相似文献   
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PURPOSE: To report the association between colonization of contact lenses with Streptococcus pneumoniae and the observation of corneal infiltrative events in a group of patients wearing disposable hydrogel lenses on an extended-wear schedule. METHODS: In a prospective clinical trial, 330 patients wore disposable hydrogels on a 6-night extended-wear and replacement schedule. The contact lens, lid, and conjunctival microbiota of these subjects was analyzed at frequent intervals and at the time of an adverse event. RESULTS: Streptococcus pneumoniae was an uncommon isolate and was recovered from only one of the 3,763 conjunctival samples, five (0.1%) of the 3,764 lid samples, and 33 (0.8%) of the 4,315 contact lens samples. Of the 33 lens samples, 10 (30%) were associated with corneal infiltrative events. Many of the events were mild inflammatory responses and resolved rapidly on discontinuation of lens wear. The presence of S. pneumoniae on the contact lens was associated with a significant risk of development of corneal infiltrates (odds ratio, 3.0; p = 0.0227, logistic-regression analysis). CONCLUSIONS: Presence of S. pneumoniae on hydrogel lenses is a significant risk factor for the development of corneal infiltrates.  相似文献   
60.
CAMPATH-1H IN RHEUMATOID ARTHRITIS--AN INTRAVENOUS DOSE-RANGING STUDY   总被引:1,自引:0,他引:1  
Forty-one patients with active and refractory rheumatoid arthritis(RA) received a total of 100, 250 or 400 mg of CAMPATH-1H (CAMPATHis a trademark of Glaxo-Wellcome group companies, registeredin the US Patent and Trademark Office) over 5 or 10 days inan open, uncontrolled study. Following therapy, patients weremonitored for adverse effects and disease activity for 6 months.Therapy was associated with prolonged peripheral blood lymphopeniain all dosing cohorts. During the month immediately followingtherapy, lymphopenia was most profound in the 400 mg cohorts.The first dose of monoclonal antibody (Mab) was associated witha ‘flu’-like syndrome, more pronounced at higherinitial doses. One patient developed haemolytic-uraemic syndrome.There were a number of dose-related infections during the earlypost-treatment period and one fatal opportunistic infectionwhich followed additional immunosuppressive therapy. Antiglobulinresponses developed in 9 of 31 patients tested. The majorityof patients showed symptomatic improvement following therapyand 20% of patients maintained a 50% Paulus response at 6 months,all of whom were in the 250 or 400 mg cohorts. CAMPATH- 1H appearsto be an effective treatment for RA. Allowing for the smallnumber of patients treated, infections were more common withhigher doses, although this was not true for adverse eventsoverall, and therapeutic responses were more sustained at higherdosing levels. The broad specificity of CAMPATH- 1H may be appropriatefor the immunotherapy of RA and future studies should aim todefine a dose with an optimal therapeutic ratio. KEY WORDS: CAMPATH-1H, Rheumatoid arthritis, Immunotherapy, Monoclonal antibody, Antiglobulin response  相似文献   
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