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131.
Until recently the only way to rescue masked epitopes in routinely processed surgical pathological material was enzymatic digestion. The use of heat for antigen retrieval, first by microwave irradiation, represents an important breakthrough in immunohistochemistry. With the acceptance of microwave oven pretreatment, various modified techniques and alternative heating methods have also been proposed. Wet autoclave pretreatment for tissue proteolysis is a highly reliable alternative to the microwave antigen retrieval technique. It provides uniform heating of the slides, hence an even enhancement of staining intensity in a variety of formalin-sensitive antigens, and it also offers consistent interlaboratory results. The method has been introduced in routine diagnostic immunohistochemistry for the detection of estrogen-and progesterone receptors, L26-, Ki-67- and bcl-2 antigens and variable types of cytokeratins (1/5/10/11, 8, 13, 19). Experimentally, wet autoclaving can be used very successfully for the immunophenotyping of p53 and mdm2 expression, for the detection of adhesion molecules (CD44, integrins) and some anti-inflammatory molecules (annexins), among others. It has produced a substantial improvement in the visualisation of silver-stained nucleolar organizer regionsassociated proteins (AgNORs) in routine paraffin sections and along with modified silver staining and standardized AgNOR parameters assessed by image analysis. Wet autoclaving-based AgNOR staining has been proposed by a European multicentric study group as the standardized method for AgNOR analysis in archival material.  相似文献   
132.
133.
PURPOSE: This article describes baseline data collection and the intervention design of Partnership for Health, a smoking cessation intervention for smokers in the Childhood Cancer Survivors Study. The purpose of this article is to evaluate demographic, psychosocial, and cancer-related factors that are associated with smoking behavior and mediators of smoking cessation. PATIENTS AND METHODS: This study includes 796 smokers from the Childhood Cancer Survivors Study database who were diagnosed with cancer before the age of 21, had survived at least 5 years, and were at least 18 years of age at the time of the baseline survey. Correlates of smoking behaviors included smoking rate, number of recent quit attempts, and nicotine dependence; two key mediators of smoking cessation, readiness to quit smoking and self-efficacy, were also assessed. RESULTS: Participants smoked, on average, 14 cigarettes/day; 53.2% were nicotine dependent, and 58% had made at least one quit attempt in the past year. Smoking behaviors were primarily associated with demographic variables; mediators of cessation were primarily associated with age at cancer diagnosis and perceived vulnerability to smoking-related illnesses. Severity of psychologic symptoms was associated with increased smoking rate, high nicotine dependence, and low self-efficacy. Support for quitting was related to smoking rate, number of quit attempts, readiness to quit smoking, and self-efficacy. CONCLUSION: These findings indicate that many cancer survivors who smoke are receptive to smoking cessation interventions. Factors related to mediators of smoking cessation might be particularly good targets for intervention.  相似文献   
134.
Although transjugular liver biopsies are frequently performed in patients with impaired blood coagulation, their impact on effecting changes in clinical management has not been assessed. We reviewed our experience with 43 consecutive transjugular liver biopsies performed over 3 years (1998?2000) at Westmead Hospital, Sydney, Australia. The technical success, procedural complication rates and subsequent management of these patients were ascertained from the medical case records. Forty‐two (28 men) patients were studied. The indications for liver biopsy were as follows: assessment of hepatitis/cirrhosis status (n = 21), evaluation of liver dysfunction following bone marrow transplantation (n = 19) and miscellaneous (n = 2). All liver biopsies were performed with a Cook 20‐G transjugular cutting needle device. Adequate histological samples were obtained in 42 (98%) of the 43 biopsies performed. The pre‐biopsy diagnoses were confirmed by histology in 28 cases (65%). A change in clinical diagnosis was observed in 12 (28%) patients, and there were changes to subsequent management in all 12 patients. Four patients developed procedural complications, including small neck haematomas in two patients and a self‐limiting biliary fistula in one. The only major complication was an extracapsular bleed from a hepatic laceration. This patient required emergency surgery but recovered. Transjugular liver biopsies can be effectively and safely performed in high‐risk patients with impaired coagulation. They aid accurate histological appraisal of liver dysfunction in these patients and influence clinical decision‐making.  相似文献   
135.
To evaluate toxicity and efficacy of chemotherapy in elderly patients (≥65 years of age) with advanced colorectal cancer, data from two consecutive trials conducted between 1984 and 1995 at the National Institute for Cancer Research were analysed comparing the results of treatment in those 65 years of age or older and in those younger than 65 years. Of 215 patients recruited, 82 elderly patients (median age 70 years, median performance status 1) received one of the following regimens based on 5-fluorouracil (5-FU): (1) weekly 5-FU 600 mg/m2 i.v. bolus (30 patients); (2) weekly 5-FU 600 mg/m2 bolus plus leucovorin (LV) 500 mg/m2 2-h i.v. infusion (28 patients); (3) Weekly 5-FU 2600 mg/m2 24-h continuous i.v. infusion plus LV 100 mg 4-h i.v. infusion and 50 mg orally every 4 h for five doses (24 patients). Overall, 1071 chemotherapy cycles were administered with a median number of 12 courses per patient. The main side effects were diarrhoea, observed in 38% of patients, stomatitis in 24% of patients and hand-foot syndrome in 13% of patients, and haematological toxicity affected only 15% of patients. No patient suffered grade IV toxicity. In three patients chemotherapy was discontinued because of toxicity (two patients suffered grade III diarrhoea, one patient grade III hand-foot syndrome). No significant difference in toxicity was evident between patients older than or younger than 65 years. Analysis of median dose intensity demonstrated no difference between the two groups. Overall objective response was observed in 18% (95% confidence limits 11–29) of elderly patients (15/82) in comparison with 23% (95% CL 17–32) of patients <65 years of age (31/133 pts). In conclusion, chemotherapy in elderly patients with advanced colorectal cancer is a safe and effective treatment with acceptable toxicity and comparable objective response rates. Received: 6 January 1998 / Accepted: 27 February 1998  相似文献   
136.
The role of glutamatergic dysfunction in the pathophysiology of OCD has hardly been explored despite recent reports implicating glutamatergic dysfunction in OCD. We decided to investigate CSF glutamate levels in adult OCD probands compared to psychiatrically normal controls. In total, 21 consenting psychotropic drug-na?ve adult OCD patients, diagnosed using SCID-IV-CV, and 18 consenting psychiatrically normal controls with age within 10 years of age of the patients, who did not have any history of head injury or neurological illness, were included into the study. Aseptically collected and stored CSF samples obtained from the patients and control subjects were used for glutamate estimation, which was carried out by a modification of the procedure described by Lund (1986). CSF glutamate (micromol/l) level was found to be significantly higher [F(1,31)=6.846, p=0.014] in OCD patients (47.12+/-4.25) compared to control subjects (41.36+/-3.63) on analysis of covariance. There was no effect of gender, age, duration of illness, Y-BOCS score, or CGI-S score on CSF glutamate levels. Our study provides preliminary evidence implicating glutamatergic excess in the pathophysiology of OCD, which needs to be further explored by studies from other centers involving larger sample sets from different age groups.  相似文献   
137.
Associations between maternal nutritional factors including energy intake, body mass index, postpartum weight change, and anemia status and maternal-infant interactions were examined in 124 mother-infant pairs from a marginally malnourished, rural Kenyan population. Anemic mothers spent less time holding and caring for their infants than nonanemic mothers. Mothers who retained their pregnancy weight gain or were able to gain weight postpartum spent more time looking at their infants than mothers who lost weight postpartum. Maternal food intake per se was not associated with patterns of infant interaction. Lower birth weight infants were held more, cared for more, and looked at face-to-face more by their mothers. Older sisters tended to be more involved in infant interactions with higher birth weight infants.  相似文献   
138.
Objective To know the characteristics of contraceptive use in Sao Paulo State collected by the Demographic and Health Survey (DHS) conducted in 1996. Methods Data of Sao Paulo in 1996 were analyzed compared with the previous DHS carried on in 1986focusing on Sao Paulo State. Contraceptive use among married or cohabiting women by age, number of children and schooling was closely examined. Age and timing of female sterilization were also analyzed. Results The results showed that unlike Brazil there was a stability of female sterilization in Sao Paulo State during 1986 and 1996. There was a pattern in Sao Paulo: up to 30 years old the pill was the most used contraceptive, after 30 there was a predominance of female sterilization, which increased with the number of children and decreased with schooling. The use of male methods had also increased in the 1986 and 1996 period, being greater in Sao Paulo than in Brazil. Sao Paulo also presented more diversity in the use of reversible contraceptives. Conclusions The predominant two contraceptive methods in Brazil and Sao Paulo changed from 1986 to 1996, i.e..from pill to female sterilization.  相似文献   
139.
PURPOSE: Tuberous sclerosis complex (OMIM 191100) is a multiorgan disease commonly associated with epilepsy refractory to anticonvulsants. Individual reports indicate that seizures in children with tuberous sclerosis might benefit from a ketogenic diet. We studied the effects of the diet introduced at 3.5 years of age in three boys with tuberous sclerosis and refractory partial seizures. METHODS: On admission a classical LCT ketogenic diet was initiated and patients were followed for 12 months. Antiepileptic drugs were maintained unless adverse effects required reduction. RESULTS: Two patients became seizure-free within 2 months on the diet. In the third patient drop attacks decreased significantly. On follow-up the diet was well accepted and without adverse effects. CONCLUSION: The ketogenic diet should be considered as a treatment option for children with tuberous sclerosis and partial seizures refractory to anticonvulsants. Our data support the need for further studies in larger cohorts to confirm the effectiveness of the ketogenic diet in this entity.  相似文献   
140.
Previous reports have shown that ortho-substituted polychlorinated biphenyls (PCBs) are uterotonic and activate phospholipase A2 to release arachidonic acid (AA) from membrane phospholipids. AA serves as the precursor to various eicosanoids, which, in addition to AA itself, are capable of modulating uterine function. To examine whether PCBs stimulate phospholipase A2 (PLA2) to mobilize arachidonic acid from late-gestation rat uterus, primary cultures of gestation day 20 (gd20) rat myometrial cells (RMC) were labeled with 0.5 microCi 3H-AA prior to a 10-, 20-, or 30-min exposure to 2,2',4,6-tetrachlorobiphenyl (PCB 50) (1-50 microM) or 0.1% DMSO (solvent control). PCB 50 stimulated the release of 3H-AA from gd20 RMC in concentration- and time-dependent manners (p < 0.05). PCB 50 stimulation of RMC was attenuated with ethylene glycol bis(2-aminoethyl ether)-N,N,N'N'-tetraacetic acid (EGTA) and nifedipine, suggesting that AA release was dependent on the influx of extracellular calcium through L-type voltage-operated calcium channels. PCB 50-induced release of AA from RMC was also attenuated with the PLA2-specific inhibitors methyl arachidonyl fluorophosphonate (MAFP), bromoenol lactone (BEL), and manoalide (p < 0.05). Stimulation of PLA2 enzymes in response to PCB exposure occurred via p38 mitogen activated protein kinase (MAPK) activation as indicated by the significant attenuation of PCB 50-induced AA release from RMC in the presence of SB 202190. In addition to stimulating AA release, PCB 50 induced a significant production of prostaglandins from gd20 RMC compared with controls (p < 0.05). These results suggest that myometrial cells express multiple PLA2 isoforms that may serve as a target and effector for ortho-substituted PCB-mediated stimulation of uterine function through arachidonic acid and prostaglandin release.  相似文献   
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