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91.
The thermal stability of IL-1 in aqueous solution as a function of temperature (5–60°C), pH (2–9), buffer (acetate, citrate, tris, and phosphate), and cyroprotectants (sugars, HSA) was investigated in this study. The analytical methodologies included RP-HPLC, SEC, ELISA, IEF-PAGE, SDS-PAGE, and bioassay. The degradation and inactivation of IL-1 at or above 39°C were attributed to autoxidation of the two cysteine residues in the denatured protein, followed by hydrophobic/covalent aggregation and precipitation. At or below 30°C, IEF- and SDS-PAGE results suggest a possible deamidation reaction. The difference in mechanism of degradation precludes the prediction of formulation shelf life from accelerated temperature data. Nonetheless, the good stability observed at 5°C suggests that a solution formulation may be feasible for IL-1.  相似文献   
92.
This study evaluates the effects of a Tele-check/Tele-emergency service on the quality of life in the elderly. Through telephone interviews a questionnaire has been repeatedly administered to explore various psychological, somatic, and social aspects in a random sample of 574 subjects aged 65 years and over (mean = 76.8 years). The findings suggest that the elderly helped by the service (in its control functioning) make less demands on health facilities (GPs visits, number of days in hospital) as compared to controls. Implications are presented and discussed.  相似文献   
93.
Urethral diverticulum in women is not a frequent disease. The diagnosis of this lesion is based on history and careful physical examination looking for a swelling on the anterior vaginal wall. A study of 15 cases is reported. The authors insist on investigations as a help to confirm and localise the diverticulum. A new technique of retrograde urethrography using a prehension cannula ("Bomelaer") is described. By this well tolerated and minimally invasive test, the visualisation of the urethral diverticulum was obtained in 14/15 patients. Associated with intravenous urography, it is certainly the most adapted strategy for diagnosis and management.  相似文献   
94.
Reactivation of electric eel acetylcholinesterase (AChE) inhibited by MeO(NH2)P(O)SMe (methamidophos) and by MeS(NH2)P(O)SMe was studied at pH 7.5 and 25° C. The former inhibited enzyme shows a rather rapid spontaneous reactivation (t1/2=3.7 h); this reactivation is accelerated by 1 M of the bispyridinium oximes TMB4 and obidoxime, and, to a lesser extent, by the monopyridinium oximes P2S and its 1-benzyl analogue (benzyl-P2A). The latter inhibited enzyme shows rapid aging (t1/2=0.6 h). Reactivation with 1 mM of the bispyridinium oximes is incomplete and reactivation with 1 mM of the monopyridinium oximes proceeds very slowly. These large differences between the properties of the two inhibited enzymes indicate that the methylthio group is the leaving group during inhibition of AChE by methamidophos. Additional support is afforded by the observation of induced aging of the former inhibited enzyme by thiourea.Upon comparison of the reactivation of AChE inhibited by methamidophos with that of AChE inhibited by an N-methyl analogue, cruf ornate, and an N,N-dimethyl analogue, tabun, it appears that the rate of spontaneous reactivation decreases with increasing alkylation of the P-NH2 group. Whereas benzyl-P2A is somewhat less active than P2S for reactivation of AChE inhibited by methamidophos, it is superior to P2S for reactivation of AChE inhibited by crufomate and also superior to P2S and to the bispyridinium oximes for AChE inhibited by tabun.  相似文献   
95.
9-Tetrahydrocannabinol (9-THC) was administered in a crossover design by smoking and IV injection to groups of heavy and light users of marihuana. Plasma concentrations of 9-THC were similar for the groups after IV injection of 5.0 mg 9-THC, but the AUC0–240 min showed a trend towards lower values for the heavy user group. To achieve a maximum desired high, both groups smoked similar amounts (about 13 mg) of 9-THC. Heavy users tended to have higher plasma levels than light users. The systemic availability of smoked 9-THC was significantly higher for the heavy users (heavy users 23±16% vs 10±7% for light users). These results also indicate that heavy cannabis users smoke more efficiently than casual smokers.Both light and heavy users showed more clinical effect following IV administration than after smoking. The response of the heavy users, both with respect to effect on heart and high, was quite comparable to that of light users.The present study does not suggest that tolerance readily develops in heavy users.  相似文献   
96.
During the last 20 years, various conservative surgical techniques have been proposed to treat larynx cancer. On the basis of our various experiences and of the ultrastructural data on the tissues treated with radiowaves, we decided to also use radiosurgery in operations under direct microlaryngoscopy. We select 18 patients suffering from epidermoid carcinoma. These patients had been referred to our ENT clinic at the Polichnico of Palermo between 1999 and 2001. The authors describe the surgical procedures used and emphasize the advantages of radiosurgery in the treatment of larynx cancer.  相似文献   
97.
PURPOSE: To determine demographic data and define prognostic factors for long-term outcome in patients presenting with high-grade osteosarcoma of bone with clinically detectable metastases at initial presentation. PATIENTS AND METHODS: Of 1,765 patients with newly diagnosed, previously untreated high-grade osteosarcomas of bone registered in the neoadjuvant Cooperative Osteosarcoma Study Group studies before 1999, 202 patients (11.4%) had proven metastases at diagnosis and therefore were enrolled onto an analysis of demographic-, tumor-, and treatment-related variables, response, and survival. The intended therapeutic strategy included pre- and postoperative multiagent chemotherapy as well as aggressive surgery of all resectable lesions. RESULTS: With a median follow-up of 1.9 years (5.5 years for survivors), 60 patients were alive, 37 of whom were in continuously complete surgical remission. Actuarial overall survival rates at 5 and 10 (same value for 15) years were 29% (SE = 3%) and 24% (SE = 4%), respectively. In univariate analysis, survival was significantly correlated with patient age, site of the primary tumor, number and location of metastases, number of involved organ systems, histologic response of the primary tumor to preoperative chemotherapy, and completeness and time point of surgical resection of all tumor sites. However, after multivariate Cox regression analysis, only multiple metastases at diagnosis (relative hazard rate [RHR] = 2.3) and macroscopically incomplete surgical resection (RHR = 2.4) remained significantly associated with inferior outcomes. CONCLUSION: The number of metastases at diagnosis and the completeness of surgical resection of all clinically detected tumor sites are of independent prognostic value in patients with proven primary metastatic osteosarcoma.  相似文献   
98.
Gomez F  Leo NA  Grigson PS 《Brain research》2000,863(1-2):52-58
Rats suppress intake of a saccharin conditioned stimulus (CS) when paired with a drug of abuse. This phenomenon, however, is not uniform across all subjects and is greater following exposure to stress and in animals that more readily self-administer drugs of abuse. The present study was designed to examine these individual differences in intake suppression following seven saccharin-morphine pairings. Plasma corticosterone also was evaluated both before and after conditioning in order to determine whether the magnitude of CS suppression is, or is not, related to circulating corticosterone levels. The findings indicated that, while all rats were exposed to the same number of saccharin-morphine pairings, only half of these animals actually suppressed intake of the saccharin CS. Moreover, the results showed that greater suppression of CS intake was associated with higher corticosterone levels at test (r=-0.84, P<0.0001). Taken together, the results demonstrate that individual differences affect not only the reduction in CS intake following taste-drug pairings, but also the associated cue-induced elevation in circulating corticosterone.  相似文献   
99.
Several studies have demonstrated that contact between the olfactory nerve and the forebrain is critical for normal olfactory bulb development. Removal of the embryonic olfactory placode results in a failure of the olfactory bulb to form, as well as causing other forebrain malformations. The current study introduces a technique that permits removal of contact between specific regions of the olfactory nerve and the bulb early in development, without causing damage to other brain regions, and without removing the peripheral olfactory organ. The manipulation, which involves insertion of a small Teflon chip between the cribriform plate and the bulb, prohibits growth of new axons into the "shadow" region behind the implant. Focal denervation of the olfactory bulb causes a decrease in bulb and layer sizes, a reduction in mitral cell number, and changes to bulb architecture. Using a battery of antibodies (OMP, MAP2, TuJ1, calretinin, calbindin, parvalbumin, TH, and GAD), we further demonstrated that 1) focal denervation alters the relationship between the olfactory nerve and the bulb, 2) the fine structure of cells in denervated regions is disrupted, and 3) cellular phenotypes change in response to loss of afferent contact. These results suggest that contact between the olfactory nerve and the bulb is important for maintaining bulb architecture and cell survival, structure, and phenotype. They also point to focal denervation as a useful technique for examining the role of neural contact in olfactory development and maintenance of the central nervous system.  相似文献   
100.
OBJECTIVE: To determine if differences between English- and Spanish-speaking parents in ratings of their children's health care can be explained by need for interpretive services. METHODS: Using the Consumer Assessment of Health Plans Survey-Child-Survey (CAHPS), reports about provider communication were compared among 3 groups of parents enrolled in a Medicaid managed care health plan: 1) English speakers, 2) Spanish speakers with no self-reported need for interpretive services, and 3) Spanish speakers with self-reported need for interpretive services. Parents were asked to report how well their providers 1) listened carefully to what was being said, 2) explained things in a way that could be understood, 3) respected their comments and concerns, and 4) spent enough time during medical encounters. Multivariate logistic regression was used to compare the ratings of each of the 3 groups while controlling for child's gender, parent's gender, parent's educational attainment, child's health status, and survey year. RESULTS: Spanish-speaking parents in need of interpretive services were less likely to report that providers spent enough time with their children (odds ratio = 0.34, 95% confidence interval = 0.17-0.68) compared to English-speaking parents. There was no statistically significant difference found between Spanish-speaking parents with no need of interpretive services and English-speaking parents. CONCLUSIONS: Among Spanish- versus English-speaking parents, differences in ratings of whether providers spent enough time with children during medical encounters appear to be explained, in part, by need for interpretive services. No other differences in ratings of provider communication were found.  相似文献   
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