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11.
In this study, we have used time-lapse video cinematography to study fertilization in 50 human oocytes that had undergone intracytoplasmic sperm injection (ICSI). Time-lapse recording commenced shortly after ICSI and proceeded for 17-20 h. Oocytes were cultured in an environmental chamber which was maintained under standard culture conditions. Overall, 38 oocytes (76%) were fertilized normally, and the fertilization rate and embryo quality were not significantly different from 487 sibling oocytes cultured in a conventional incubator. Normal fertilization followed a defined course of events, although the timing of these events varied markedly between oocytes. In 35 of the 38 fertilized oocytes (92%), there were circular waves of granulation within the ooplasm which had a periodicity of 20-53 min. The sperm head decondensed during this granulation phase. The second polar body was then extruded, and this was followed by the central formation of the male pronucleus. The female pronucleus formed in the cytoplasm adjacent to the second polar body at the same time as, or slightly after, the male pronucleus, and was subsequently drawn towards the male pronucleus until the two abutted. Both pronuclei then increased in size, the nucleoli moved around within the pronuclei and some nucleoli coalesced. During pronuclear growth, the organelles contracted from the cortex towards the centre of the oocyte, leaving a clear cortical zone. The oocyte decreased in diameter from 112 to 106 microm (P < 0.0001) during the course of the observation period. The female pronucleus was significantly smaller in diameter than the male pronucleus (24.1 and 22.4 microm respectively, P = 0.008) and contained fewer nucleoli (4.2 and 7.0 respectively, P < 0.0001). After time-lapse recording, oocytes were cultured for 48 h prior to embryo transfer or cryopreservation. Embryo quality was related to fertilization events and periodicity of the cytoplasmic wave, and it was found that good quality embryos arose from oocytes that had more uniform timing from injection to pronuclear abuttal and tended to have a longer cytoplasmic wave. In conclusion, we have shown that time-lapse video cinematography is an excellent tool for studying fertilization and early embryo development, and have demonstrated that human fertilization comprises numerous complex dynamic events.   相似文献   
12.
Metastatic dissemination is the primary cause of death in ovarian cancer (OvCa) patients, and dissemination to pleural and peritoneal effusions is a common clinical event. Effusion samples were collected from 15 OvCa patients. Twenty-six samples were collected prospectively, two were archival, and eight were taken from patients with other malignancies. Twenty-nine samples were from malignant ascites, and seven specimens were pleural fluids. In addition, six ascites and two pleural fluids from noncancer patients were studied as effusion controls. Effusion supernatants were tested for migration-stimulation activity, using A2058 human melanoma cells as the index responder cell. Malignant samples induced a 400-1200% increase in migration. Sixty percent of the migration was inhibited by incubation of the malignant fluid with antifibronectin (FN) antibody, in contrast to 75% inhibition of control fluid-stimulated migration (P = 0.017). Gelatin zymography and Western blot analyses showed that latent and activated MMP-2 and MMP-9 collagenases, and tissue inhibitor of metalloproteinase-2 (TIMP-2) were present in all malignant fluids. Serial samples were taken from several patients, and a trend for correlation between MMPs and clinical behavior of the tumors was shown. Free TIMP-2 correlated with CA-125 levels in two patients for whom serial samples were available. The demonstration of promigratory and proinvasive activity in malignant effusions is consistent with their association with other metastatic disease in OvCa patients and their function as a haven for metastatic cells.  相似文献   
13.
Lung carcinoma remains one of the most frequent and aggressive human neoplasms. Fortunately, in the last decades, the increasing knowledge of the molecular mechanisms leading to cancer development has allowed the use of targeted therapies with improvement of prognosis in many patients. Clinical management has also changed after the introduction of endobronchialultrasonographic bronchoscopy that allows a conservative staging of lung tumors, avoiding the need of mediastinoscopy for lymph node staging. Lung pathologists and cytopathologists are facing the challenge of giving the more comprehensive prognostic and predictive information with ever smaller tissue or cytological samples. The aim of this review is to summarize the molecular testing for non-small cell lung carcinoma and how pathologists can contribute to the patient's outcome with a conscious management of biological samples.  相似文献   
14.
OBJECTIVE: To examine lifetime and current psychiatric comorbidity measures as predictors of drug abuse treatment retention, and to test the generalizability of results across treatment agencies in diverse settings and with varying practices. DATA SOURCES/STUDY SETTING: The national Drug Abuse Treatment Outcome Studies (DATOS), a longitudinal study of clients from 96 treatment agencies in 11 U.S. cities. STUDY DESIGN: The design is naturalistic and uses longitudinal analysis of treatment retention in long-term residential, outpatient drug-free, and outpatient methadone treatment modalities; client background (including psychiatric comorbidity) and program service provision are predictors. Clinical thresholds for adequate treatment retention were 90 days for long-term residential and outpatient drug-free, and 360 days for outpatient methadone. Psychiatric indicators included lifetime DSM-III-R diagnoses of depression/anxiety and antisocial personality, and dimensional measures of current symptoms for depression and hostility. DATA COLLECTION/EXTRACTION METHODS: Data include structured interviews with clients, a survey of treatment program administrators, and program discharge records. PRINCIPAL FINDINGS: Dimensional measures of current psychiatric symptoms emerged as better predictors than lifetime DSM-III-R diagnoses. In addition, the predictive association of hostility with retention varied significantly across treatment agencies, both in the long-term residential and outpatient drug-free modalities. Other notable findings were that on-site mental health services in long-term residential programs were associated with better retention for clients with symptoms of hostility. CONCLUSIONS: Assessment issues and stability of results across programs are important considerations for treatment research and practice.  相似文献   
15.
A simple auto-evaluation sheet is presented for the proper assessment of the patient's condition after surgery. Stress is put not only on weight loss, but on other important factors as well.  相似文献   
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As many as 29% of women suffer from migraine headache, yet it remains a poorly understood phenomenon. Our purpose in conducting this pilot study was to determine the relationships among migraine pain, disability, depressive symptomatology, and coping in women. A convenience sample of 34 women was recruited from university and workplace populations. Nineteen women met the International Headache Society criteria for migraine, while 15 women served as a nonmigraine comparison group. Participants completed eight instruments measuring migraine pain, disability, depressive symptomatology, and coping. The two groups of women were not significantly different on demographic variables. Migraineurs scored significantly higher for pain characteristics, disability, depressive symptomatology, and total coping scores.  相似文献   
19.
BACKGROUND: A clinical diagnosis of familial hypercholesterolaemia (FH) is often made in the absence of tendon xanthomata (TX), which are not usually present before the fourth decade of life. The prognosis of treated non-xanthomatous (TX-) FH is uncertain and the objective of this study was to compare mortality from coronary heart disease (CHD) in patients with treated TX+ (definite) and TX- (possible) heterozygous FH. METHODS: A diagnosis of definite or possible FH was based on raised cholesterol levels (>7.5 mmol/l) and a family history of premature CHD or hypercholesterolaemia. Patients were recruited from 21 outpatient lipid clinics in the UK from 1980 to 1998. The cohort of 1569 patients with TX+ FH were followed for 12754 person years and the cohort of 1302 patients with TX- FH for 10238 person years. The standardised mortality ratio (SMR) was calculated from the ratio of the number of deaths observed to the number expected in the general population of England and Wales (SMR=100 for reference population). FINDINGS AND DISCUSSION: CHD accounted for 64 (63%) of the 102 deaths in the TX+ cohort and 38 (57%) of the 67 deaths in the TX- cohort with the SMR for a fatal coronary event being, respectively, 294 (95% confidence interval 228, 380, P<0.00001) and 205 (95% CI 145, 282, P=0.0001). The similarly elevated CHD mortality risk suggests that, in adulthood, both groups of patients should be treated equally aggressively with HMG Co A reductase inhibitors (statins).  相似文献   
20.
Seventy-five patients, 13 to 49 years of age, with acute nonlymphoblastic leukemia in first remission were treated with cyclophosphamide, fractionated total body irradiation, and marrow transplantation from an HLA-identical sibling and randomized to receive either cyclosporine (CSP) (n = 36) or methotrexate (MTX) (n = 39) as prophylaxis for graft-v-host disease (GVHD). All patients engrafted, and 22 who were given CSP and 21 who were given MTX, are alive at 20 to 47 (median, 35) months (P = .5). Engraftment as assessed by granulocyte recovery (P less than .0005) and platelet transfusion requirement (P = .01) was faster in patients on CSP. Twelve patients (33%) on CSP and 22 (56%) on MTX developed acute GVHD of grades II through IV (P = .07) and 15 of 30 on CSP and 14 of 32 on MTX that were at risk developed chronic GVHD. The most frequent causes of death were interstitial pneumonitis and marrow relapse of leukemia, which occurred with similar frequency in both groups. Beneficial effects observed in patients on CSP included less severe mucositis and shorter duration of hospitalization; adverse effects included renal function impairment and hypertension. These data confirm that CSP is a useful immunosuppressant in patients undergoing marrow transplantation but fail to show a significant improvement in survival as compared with the standard regimen of MTX.  相似文献   
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