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151.
We report three patients who developed severe supraglottic airway obstruction due to Epstein-Barr virus lymphoproliferative disease following allogeneic bone marrow transplantation. In addition to enlarged pharyngeal lymphoid tissue seen in all three patients, two had supraglottic airway narrowing and two developed pulmonary lymphoproliferative disease. They were treated with unmanipulated T cells or EBV-specific cytotoxic T lymphocytes. Life-threatening upper airway obstruction is a radiologically detectable complication of allogeneic bone marrow transplantation in children. Received: 12 August 1997 Accepted: 11 December 1997  相似文献   
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153.
Objective To determine whether increasing maternal age increases the risk of operative delivery and to investigate whether such a trend is due to fetal or maternal factors.
Design Analysis of prospectively collected data on a maternity unit database.
Setting A postgraduate teaching hospital.
Population 6410 nulliparous women with singleton cephalic pregnancies delivering at term (37–42) weeks of gestation) between 1 January 92 and 31 December 95.
Main outcome measures Mode of delivery, rates of prelabour caesarean section, induction of labour and epidural usage.
Results There was a positive, highly significant association between increasing maternal age and obstetric intervention. Prelabour (  P < 0.001  ) and emergency (   P < 0.001  ) caesarean section, instrumental vaginal delivery (spontaneous labour   P < 0.001  ; induced labour   P = 0.001  ), induction of labour (   P < 0.001  ) and epidural usage in spontaneous labour (  P = 0.005  ) all increased with increasing age. In the second stage of labour fetal distress and failure to advance, requiring instrumental delivery, were both more likely with increasing maternal age (in both   P < 0.001  ). Epidural usage in induced labour and the incidence of small for gestational age newborns did not increase with increasing maternal age (P = 0.68 and  P = 0.50  , respectively).
Conclusions This study demonstrates that increasing maternal age is associated with an incremental increase in obstetric intervention. Previous studies have demonstrated a significant effect in women older than 35 years of age, but these data show changes on a continuum from teenage years. This finding may reflect a progressive, age-related deterioration in myometrial function.  相似文献   
154.
The herbicide atrazine is a putative endocrine disruptor. The present studies investigated the effects of atrazine in male Japanese quail during sexual maturation. Atrazine was administered for two weeks in the diet or systemically to birds under long photoperiods. Atrazine had no effect on mortality but depressed both feed intake and growth (average daily gain [ADG] in g/day) at dietary concentrations of 1000 ppm. Atrazine in the diet at 10 ppm, but at no other concentrations, increased testes weight and gonadal-somatic-index and decreased the seminiferous tubule diameter-to-testis weight ratio. However, there were no effects on absolute tubule diameter, relative stage of testicular development, or the presence of a lumen. Atrazine in the diet at 1000 ppm increased circulating concentrations of testosterone but this effect was not observed consistently in all studies. Dietary atrazine at 10 ppm increased circulating concentrations of estradiol. Moreover, in one study, atrazine at 1000 ppm in the diet decreased circulating concentrations of luteinizing hormone. Atrazine administered systemically exerted no effect on indices of growth or reproduction. Atrazine did not mimic the effects of either estradiol or tamoxifen in male quail; thus, atrazine did not exhibit overt estrogenic or anti-estrogenic activity. Conversely, atrazine augmented the effects of testosterone and estradiol on testis regression, presumably by increasing the negative-feedback effects of these sex-steroids on follicle stimulating hormone secretion. It is concluded that atrazine up to 1000 ppm in the diet may exert some effects on reproductive development in sexually maturing male birds, but these are inconsistent and modest.  相似文献   
155.
OBJECTIVE: To determine the effects of monophasic oral contraceptives on the nasal respiratory epithelium in premenopausal women. DESIGN: Prospective open clinical trial. SETTING: Outpatient Family Planning Centre. PATIENT(S): Eighty-eight premenopausal women, with ovulatory cycle, who were planning to take oral contraceptives. INTERVENTION(S): Baseline endovaginal ultrasound examination and blood test to measure serum progesterone to confirm ovulatory cycle. Thirty-eight women on pill containing 30 microg ethinylestradiol (EE) plus 75 microg gestodene, and 35 women on pill containing 15 microg ethinylestradiol plus 60 microg gestodene. MAIN OUTCOMES/MEASURE(S): Cytological changes on the nasal respiratory epithelium evaluated with the maturation index performed during the follicular, periovular, and luteal phases of the menstrual cycle, and on the sixth cycle of pill intake. RESULT(S): Hematoxylin-eosin staining for the maturation index showed similar trophic cytological aspects between the nasal and vaginal epithelium during the menstrual cycle and pill usage. Both the nasal and vaginal cytological samples showed higher maturation indexes during both the follicular and the periovular phases than during the luteal phase. Women on pill containing 15 microg EE showed lower trophic aspects in the nasal cytological samples compared with those on pill with 30 microg EE. CONCLUSION(S): Along with the vaginal cells, the nasal respiratory epithelium is an ovarian steroid target. The maturation index of the nasal respiratory epithelium seems to depend on the variation of the ovarian steroids during the menstrual cycle and on the iatrogenic effects of oral contraceptives.  相似文献   
156.
Metastastic tumours involving the epididymis are rare and most often found in patients with disseminated disease. It is even more unusual when the metastasis of the epididymis is the first sign of tumour recurrence. We report a case of an asymptomatic recurrent colon carcinoma presenting as metastasis in the epididymis. Although metastatic cancer presenting as an intra-scrotal mass is extremely rare, it should be considered as a possibility in patients who present with a mass involving the testicle or epididymis.  相似文献   
157.
PURPOSE: Most cases of non-small-cell lung cancer (NSCLC) with dramatic responses to gefitinib have specific activating mutations in the epidermal growth factor receptor (EGFR), but the predictive value of these mutations has not been defined in large clinical trials. The goal of this study was to determine the contribution of molecular alterations in EGFR to response and survival within the phase II (IDEAL) and phase III (INTACT) trials of gefitinib. PATIENTS AND METHODS: We analyzed the frequency of EGFR mutations in lung cancer specimens from both the IDEAL and INTACT trials and compared it with EGFR gene amplification, another genetic abnormality in NSCLC. RESULTS: EGFR mutations correlated with previously identified clinical features of gefitinib response, including adenocarcinoma histology, absence of smoking history, female sex, and Asian ethnicity. No such association was seen in patients whose tumors had EGFR amplification, suggesting that these molecular markers identify different biologic subsets of NSCLC. In the IDEAL trials, responses to gefitinib were seen in six of 13 tumors (46%) with an EGFR mutation, two of seven tumors (29%) with amplification, and five of 56 tumors (9%) with neither mutation nor amplification (P = .001 for either EGFR mutation or amplification v neither abnormality). Analysis of the INTACT trials did not show a statistically significant difference in response to gefitinib plus chemotherapy according to EGFR genotype. CONCLUSION: EGFR mutations and, to a lesser extent, amplification appear to identify distinct subsets of NSCLC with an increased response to gefitinib. The combination of gefitinib with chemotherapy does not improve survival in patients with these molecular markers.  相似文献   
158.
PURPOSE: To determine the toxicity, maximal tolerated dose, and clinical and immunologic response to autologous dendritic cells pulsed with melanoma-associated antigen gp100-derived G280-9V peptide. PATIENTS AND METHODS: Twelve HLA-A*0201(+) patients with advanced melanoma were administered dendritic cells pulsed with G280-9V peptide. Cohorts of three patients were administered 5 x 10(6), 15 x 10(6), and 50 x 10(6) cells i.v. every 3 weeks for six doses according to a dose escalation scheme. Three additional patients were treated at the highest dose. No additional cytokines or therapies were coadministered. The immunogenicity of G280-9V-pulsed dendritic cells was measured by IFN-gamma ELISPOT assay, tetramer assay, and (51)Cr release assay comparing prevaccination to postvaccination blood samples. Response to treatment was assessed by Response Evaluation Criteria in Solid Tumors. RESULTS: CD8(+) immunity to the native G280 was observed in 8 (67%) patients as measured by ELISPOT and in 12 (100%) patients as measured by tetramer assay. Of the 9 patients tested, 9 (100%) had measurable high-avidity CTL activity as defined by lysis of allogeneic melanoma lines, which coexpress HLA-A*0201 and gp100. The median follow-up of the entire cohort is 43.8 months. Two (17%) partial responses were observed and 3 (25%) patients had stable disease. The median survival of the treated population was 37.6 months. At this time, three patients are alive, including one patient who continues to respond without additional treatment. CONCLUSION: The high rate of immunization as measured by three independent assays and the occurrence of clinical regression support continued investigation of G280-9V peptide as a candidate epitope in melanoma vaccine formulations.  相似文献   
159.
160.
Testis cancer is considered a rare‐incidence cancer but comprises the third most common cancer diagnosed within the adolescent and young adult (AYA) years (15–39 years). Most testis cancer patients can anticipate a survival outcome in excess of 95%. However, there are subgroups of AYA patients where outcomes are considerably worse, including younger adolescents, patients with certain histological subtypes, or from certain ethnic backgrounds. For those cured with chemotherapy, the toxicity of treatment and burden of late effects is significant. Newer germ cell tumor–specific biomarkers may identify patients who do not require further treatment interventions or may detect early recurrence, potentially reducing the burden of treatment required for cure. An international collaboration for this rare tumor is creating the forum for trial design, where these biomarker research questions are embedded. Going forward, AYA testis cancer patients could benefit from having a more personalized treatment plan, tailored to risk, that minimizes the overall burden of late effects.  相似文献   
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