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171.
BACKGROUND: The Shipman Inquiry recommended mortality rate monitoring if it could be 'shown to be workable' in detecting a future mass murderer in general practice. AIM: To examine the effectiveness of cumulative sum (CUSUM) charts, cross-sectional Shewhart charts, and exponentially-weighted, moving-average control charts in mortality monitoring at practice level. DESIGN OF STUDY: Analysis of Scottish routine general practice data combined with estimation of control chart effectiveness in detecting a 'murderer' in a simulated dataset. METHOD: Practice stability was calculated from routine data to determine feasible lengths of monitoring. A simulated dataset of 405,000 'patients' was created, registered with 75 'practices' whose underlying mortality rates varied with the same distribution as case-mix-adjusted mortality in all Scottish practices. The sensitivity of each chart to detect five and 10 excess deaths was examined in repeated simulations. The sensitivity of control charts to excess deaths in simulated data, and the number of alarm signals when control charts were applied to routine data were estimated. RESULTS: Practice instability limited the length of monitoring and modelling was consequently restricted to a 3-year period. Monitoring mortality over 3 years, CUSUM charts were most sensitive but only reliably achieved >50% successful detection for 10 excess deaths per year and generated multiple false alarms (>15%). CONCLUSION: At best, mortality monitoring can act as a backstop to detect a particularly prolific serial killer when other means of detection have failed. Policy should focus on changes likely to improve detection of individual murders, such as reform of death certification and the coroner system.  相似文献   
172.
Inhaled beta-agonists can produce bronchodilatation and reduce airway hyperreactivity in patients with asthma. Using these two measures, we compared inhaled bitolterol (three puffs, 1110 micrograms), albuterol (two puffs, 180 micrograms), and placebo administered by metered-dose inhaler in a blinded, crossover study of 40 subjects with chronic asthma. On each study day, subjects underwent histamine challenges at 1 1/2 hours before, and 1/2, 2, 4, 6, and 8 hours after inhaling one of the three test-drug treatments. Both drugs produced significant bronchodilatation at 30 minutes through 4 hours and significant effects on airway reactivity at 30 minutes through 2 hours (p less than 0.05). Bitolterol also produced small but significant bronchodilator effects at 6 hours and effects on airway reactivity at 4 hours (p less than 0.05). Effects of bitolterol on airway reactivity diminished significantly more slowly than effects of albuterol in subjects with baseline provocative concentration causing a 20% fall in FEV1 greater than or equal to 1.0 mg/ml of histamine (half-life of biologic effect 1.37 versus 0.92 hours; p less than 0.05) but not in subjects with baseline provocative concentration causing a 20% fall in FEV1 less than or equal to 1.0 mg/ml (half-life of biologic effect of 1.01 versus 1.00 hours; p greater than 0.05).  相似文献   
173.
Glomus tumors are tumors of pericytic origin and are usually found in the distal extremities. Glomus tumors have rarely been reported in viscera. The authors report a glomus tumor of the colon that caused rectal bleeding in a 40-yr-old man and was biopsied and excised endoscopically. The histology and immunohistochemical profile of the tumor are described and the literature on visceral glomus tumors is reviewed.  相似文献   
174.
A joint project between general practitioners and the South Eastern Health Board resulted in the establishment of a network of computerised practices collecting morbidity data in 1998 - 1999. Five practices established age sex registers for public and private patients. The International Classification of Primary Care 2 (ICPC-2) was used to define inclusion criteria for a range of illnesses relevant to primary care and public health. Problems arose in validating and extracting data in three practices. Disease prevalence for 17 illnesses was established for two practices only. The project clearly established the problems associated with morbidity data collection in general practice which include absence of a national patient registration system, absence of a national electronic messaging standard, difficulties extracting data from practice software systems and the need for a high level of dedicated staff and resources to implement such a project.  相似文献   
175.
BACKGROUND: Patients with familial adenomatous polyposis have a nearly 100 percent risk of colorectal cancer. In this disease, the chemopreventive effects of nonsteroidal antiinflammatory drugs may be related to their inhibition of cyclooxygenase-2. METHODS: We studied the effect of celecoxib, a selective cyclooxygenase-2 inhibitor, on colorectal polyps in patients with familial adenomatous polyposis. In a double-blind, placebo-controlled study, we randomly assigned 77 patients to treatment with celecoxib (100 or 400 mg twice daily) or placebo for six months. Patients underwent endoscopy at the beginning and end of the study. We determined the number and size of polyps from photographs and videotapes; the response to treatment was expressed as the mean percent change from base line. RESULTS: At base line, the mean (+/-SD) number of polyps in focal areas where polyps were counted was 15.5+/-13.4 in the 15 patients assigned to placebo, 11.5+/-8.5 in the 32 patients assigned to 100 mg of celecoxib twice a day, and 12.3+/-8.2 in the 30 patients assigned to 400 mg of celecoxib twice a day (P=0.66 for the comparison among groups). After six months, the patients receiving 400 mg of celecoxib twice a day had a 28.0 percent reduction in the mean number of colorectal polyps (P=0.003 for the comparison with placebo) and a 30.7 percent reduction in the polyp burden (the sum of polyp diameters) (P=0.001), as compared with reductions of 4.5 and 4.9 percent, respectively, in the placebo group. The improvement in the extent of colorectal polyposis in the group receiving 400 mg twice a day was confirmed by a panel of endoscopists who reviewed the videotapes. The reductions in the group receiving 100 mg of celecoxib twice a day were 11.9 percent (P=0.33 for the comparison with placebo) and 14.6 percent (P=0.09), respectively. The incidence of adverse events was similar among the groups. CONCLUSIONS: In patients with familial adenomatous polyposis, six months of twice-daily treatment with 400 mg of celecoxib, a cyclooxygenase-2 inhibitor, leads to a significant reduction in the number of colorectal polyps.  相似文献   
176.
Patterns of autoantibody production are diagnostic of many autoimmune disorders; the recent observation of additional autospecificities towards stress-induced proteins may also provide insight into the mechanisms by which such responses arise. Grp78 (also known as BiP) is a target of autoaggressive B and T cell responses in our murine model of anti-Ro (SS-A) autoimmunity and also in rheumatoid arthritis. In this report we demonstrate reciprocal intermolecular spreading occurs between Ro52 and Grp78 in immunized mice, reflecting physiological association of these molecules in vivo. Moreover, we provide direct biochemical evidence that Grp78 associates with the clinically relevant autoantigen, Ro52 (SS-A). Due to the discrete compartmentalization of Ro52 (nucleocytoplasmic) and Grp78 (endoplasmic reticulum; ER) we propose that association of these molecules occurs either in apoptotic cells, where they have been demonstrated indirectly to co-localize in discrete apoptotic bodies, or in B cells themselves where both Ro52 and Grp78 are known to bind to immunoglobulin heavy chains. Tagging of molecules by association with Grp78 may facilitate receptor mediated phagocytotsis of the complex; we show evidence that exogenous Grp78 can associate with cell surface receptors on a subpopulation of murine splenocytes. Given the likelihood that Grp78 will associate with viral glycoproteins in the ER it is possible that it may become a bystander target of the spreading antiviral immune response. Thus, we propose a model whereby immunity elicited towards Grp78 leads to the selection of responses towards the Ro polypeptides and the subsequent cascade of responses observed in human disease.  相似文献   
177.
178.
The Mater Misericordiae Hospital is a 575-bed tertiary referral centre with busy medical and surgical subspecialty services (including the national cardiac, cardiothoracic, spinal cord injury and pulmonary hypertension units). An audit of in-patient referrals to a neurology service was carried out over the twelve-month period of January to December 2002 inclusively. Five hundred and seventy seven inpatients were evaluated and managed in conjunction with the referring services. Consultation by the neurological service led to a significant contribution in the management of clinical cases in one of three ways: establishing a de novo diagnosis in patients admitted with active neurological symptoms where no working diagnosis exists (40.7% of referrals), significant alteration in diagnosis where the referring service have already established a specific working diagnosis (11.1% of referrals), or offering advice in the ongoing management of active neurological symptoms when the diagnosis is historically established and secure (48.2% of referrals). In order of frequency the most common reason for referral was stroke (131 cases (22.7%)), seizures unrelated to alcohol (59 cases (10.2%)), alcohol-related neurological problems (55 cases (9.5%)), movement disorders (41 cases (7.1%)), neuromuscular (40 cases (6.9%)), coma (35 cases (6%)), disorders of cognition (31 cases (5.3%)), acute headache (28 case (4.8%)) and functional neurological syndromes (26 cases (4.5%)). This audit highlights the value of a consulting neurology service in a multidisciplinary tertiary referral setting.  相似文献   
179.
180.
BACKGROUND. Several new antibacterial drugs have been introduced in the last 10 years with the aim of improved treatment of respiratory tract infection. AIM. The study set out to use repeat consultations as a measure of the outcome of antibiotic treatment for respiratory tract infection, and to develop a simple model for discussion of the cost effectiveness of alternative antibiotic treatments. METHOD. All consultations to one practice during a single winter were reviewed by one general practitioner. RESULTS. A total of 1140 patients had acute symptoms suggestive of respiratory infection. Of these, 899 patients (79%) were prescribed antibiotics at the first consultation and 160 of the 899 patients (18%) returned for one or more repeat consultations; only nine repeat consultations were due to adverse effects of the antibiotics prescribed. Only two patients were admitted to hospital for respiratory symptoms following initial antibiotic therapy and both patients had additional reasons for their admission. Using the highest estimates, the cost of a repeat consultation was found to be 28.54 pounds. These data were used to calculate how much more might be spent on more effective antibiotics at the first consultation. It would be difficult to justify increasing the cost of antibiotic treatment by more than 5 pounds per patient, even if the new treatment were 100% effective and all repeat consultations were due to treatment failure (5 pounds is equal to 28.54 pounds x 0.18, which is the maximum cost of a repeat consultation multiplied by the proportion of patients prescribed antibiotics who make repeat consultations). CONCLUSION. From these results and a review of the literature it can be concluded that new antibacterial drugs will have to be carefully targeted if they are to prove cost effective in practice. Other methods for reducing repeat consultation merit investigation.  相似文献   
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