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71.
Among patients with coronavirus disease (COVID-19), IgM levels increased early after symptom onset for those with mild and severe disease, but IgG levels increased early only in those with severe disease. A similar pattern was observed in a separate serosurveillance cohort. Mild COVID-19 should be investigated separately from severe COVID-19.  相似文献   
72.
Male Syrian hamsters were exposed to 30 5 ppm nitrogen dioxide for 22 hr daily for 3 wk. Nitrogen dioxide-exposed hamsters sacrificed at various times during the 3 wk exposure showed a general loss of body weight and an increased dry lung weight when compared with the controls, which were housed in a similar, but nitrogen dioxide-free environment. Analysis of total lung collagen and total lung elastin revealed a net decrease in the moieties within 4 and 10 days, respectively, following commencement of nitrogen dioxide exposure. Total lung collagen returned toward pre-exposure levels by the 14th day of nitrogen dioxide exposure. Total lung elastin did not return toward normal until termination of nitrogen dioxide exposure. Recovery in room air for 3 wk following 21 days of nitrogen dioxide exposure restored the total pulmonary collagen and elastin to values similar to the control groups. These data suggest that the dynamics of elastin and collagen degradation and synthesis differ during and after nitrogen dioxide exposure. Lung collagen loss was observed earlier and was restored to normal values during the continuation of nitrogen dioxide exposure. Lung elastin loss occurred later and persisted during the entire period of exposure but returned to normal after exposure was terminated.  相似文献   
73.
BACKGROUND: In 2006, all local education agencies in the United States participating in federal school meal programs were required to establish school wellness policies. This study documented the strength and comprehensiveness of 1 state's written district policies using a coding tool, and tested whether these traits predicted school‐level implementation and practices. METHODS: School wellness policies from 151 Connecticut districts were evaluated. School principal surveys were collected before and after the writing and expected implementation of wellness policies. Sociodemographic variables were assessed for each district, including enrollment, population density, political climate, racial composition, and socioeconomic status. Changes in school‐level policy implementation before and after the federal wellness policy mandate were compared across districts by wellness policy strength; policies were compared based on district‐level demographics. RESULTS: Statewide, more complete implementation of nutrition and physical activity policies at the school level was reported after adoption of written policies. Districts with stronger, more comprehensive policies were more successful in implementing them at the school level. Some sociodemographic characteristics predicted the strength of wellness policies. CONCLUSIONS: Written school wellness policies have the potential to promote significant improvements in the school environment. Future regulation of school wellness policies should focus on the importance of writing strong and comprehensive policies.  相似文献   
74.
PURPOSE: To evaluate the efficacy and toxicity of irinotecan in patients with metastatic platinum-resistant or platinum-refractory epithelial ovarian cancer or primary peritoneal cancer. PATIENTS AND METHODS: Thirty-one patients with measurable disease were enrolled in our study at The University of Texas M.D. Anderson Cancer Center. Twenty-five of these patients were treated with irinotecan at a dose of 300 mg/m2 intravenously for 90 minutes every 3 weeks; the remaining six patients were treated with 250 mg/m2 because their age was greater than 65 years. Median age was 57 years (range, 38 to 74 years). The majority (84%) had a Zubrod performance status of 0. All patients were evaluated for irinotecan toxicity, and 29 (94%) were evaluable for response. RESULTS: The overall response rate was 17.2%. One patient (3%) had a complete response, four (14%) had partial responses, 14 (48%) had stable disease, and 10 had (35%) disease progression. Median progression-free survival was 2.8 months (range, 1.1 to 16 months), median duration of response was 1.4 months (range, 0.7 to 10.1 months); median survival from primary diagnosis was 24.3 months (range, 6.5 to 85.7 months); and median survival from initiation of irinotecan was 10.1 months (range, 2.3 to 34 months). Major toxicities included fatigue (16 patients), neutropenia (11 patients), diarrhea (nine patients), nausea (10 patients), and anorexia (seven patients). Eleven patients required dose reductions because of these toxicities. No treatment-related deaths occurred. CONCLUSION: Irinotecan has moderate efficacy and substantial toxicity in patients with metastatic platinum-resistant or platinum-refractory epithelial ovarian or primary peritoneal cancer.  相似文献   
75.
In this study we demonstrated that natural killer (NK) cell lysis by human peripheral blood nonadherent (NA) cells against K562 target cells was rapidly inhibited by four agents that inhibit the lipoxygenase pathway of arachidonic acid metabolism, nordihydroguaiaretic acid (NDGA), U-60257, alpha-phenanthroline, and esculetin. However, human NK cells activated by interferons (IFN) or poly I:C were partially resistant to suppression by NDGA and U-60257. Pretreatment of the NA cells with the four lipoxygenase inhibitors at 37 degrees C for 18 h led to suppression of NK activity. The inhibition of NK activity by NDGA was not reversed by aspirin at a concentration that inhibits PGE2 synthesis. Thus, suppression of NK activity by NDGA was not mediated by the effects on PGE2 synthesis. However, the inhibition of endogenous NK activity by NDGA, U-60257, alpha-phenanthroline, or esculetin was partially reversed by IFN or poly I:C. These results suggest that products of lipoxygenation are required for maintenance of human NK activity.  相似文献   
76.
A 79-year-old woman in the course of a syncope evaluation is shown to have a trazodone-related cardiac arrhythmia confirmed by drug rechallenge. This nontricyclic antidepressant should be considered as potentially arrhythmogenic despite its generally favorable cardiovascular profile.  相似文献   
77.
Large single-fraction irradiation is effective palliation for advanced ovarian cancer. It has an acceptable complication rate and requires only a limited number of visits (i.e., one treatment per 4-week course) to administer. Forty-two patients received single or multiple fractions of (three maximum) 10 Gray (Gy) to the pelvis. Most patients had advanced disease, 71.4% had Stage III or IV and 90.5% Grade 2 or 3 at the time of diagnosis. Forty patients had received preirradiation chemotherapy. Tumor size before and after radiotherapy was evaluable in 34 patients and decreased in 25. Bleeding decreased or stopped in 15 of 21 patients, and pain lessened or ceased in 11 of 20 patients. Thirteen patients had surgical procedures performed after irradiation therapy. Ten had gastrointestinal procedures, and in six radiation injury was believed to be the main contributor to complication. Hemorrhagic cystitis or proctitis occurred 6 to 18 months after irradiation in four patients. Three of these four patients received three 10 Gy fractions. The safest and most efficient dose may be one or two fractions, since three 10 Gy fractions may not increase palliation.  相似文献   
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The rarity of Stage II endometrial carcinoma and variable treatment modalities have made the evaluation of prognostic factors difficult. Clinical, surgical, and pathologic characteristics were evaluated in 64 patients treated with whole pelvic irradiation and intracavitary radium followed by hysterectomy at The University of Texas M.D. Anderson Hospital and Tumor Institute from January 1965 to December 1983. Comparison of 5-year actuarial survival rates revealed the following statistically significant categories: age, grade, depth of myometrial invasion, disease extent at surgery including lymph node metastases, and pelvic cytology. Race, weight, and cell type were not significant prognostic factors. Evaluation of prognostic factors at surgery includes pelvic and para-aortic lymph node biopsies, omental biopsy, pelvic cytologic washings, and biopsy of any suspicious tissues. Patients with adverse prognostic factors are candidates for trials with adjuvant therapy.  相似文献   
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