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11.
OBJECTIVE: The primary objectives of this study were to compare the effect of spinal manipulation vs. sham manipulation on a) circulating plasma levels of the prostaglandin F2a metabolite, 15-keto-13,14-dihydroprostaglandin (KDPGF2a), b) perceived abdominal and back pain and c) perceived menstrual distress in women with primary dysmenorrhea. DESIGN: This randomized clinical pilot study investigated the outcome measures before and after either a spinal manipulation treatment (SMT) or a sham manipulation. SETTING: All subjects were treated at the National College Chiropractic clinic, a private chiropractic clinic in the suburban Chicago area. PARTICIPANTS: Forty-five women with a history of primary dysmenorrhea were recruited from the local community. The volunteers ranged in age from 20-49 (mean age = 30.3 yr), and were entered into the study between April 1990 and January 1991. Twenty-four were randomly assigned to the spinal manipulation group and 21 were assigned to the sham group. INTERVENTIONS: Subjects treated with spinal manipulation were placed in a side-lying position with the bottom leg straight and the top leg flexed at the knee and hip. They received a high-velocity, short lever, low-amplitude thrust to all clinically relevant vertebral levels within T10 and L5-S1 and the sacroiliac joints. In the sham manipulation, subjects were placed in a side-lying position with both hips and knees flexed. Their manipulation consisted of a similar thrust administered to the midline base of the sacrum. OUTCOME MEASURES: Perceived abdominal and back pain were measured with a visual analog scale, and menstrual distress was measured with the Menstrual Distress Questionnaire. Both were administered 15 min before and 60 min after treatment. Blood samples were collected by venipuncture for the determination of plasma levels of KDPGF2a at the same times. The plasma was then assayed for KDPGF2a by radioimmunoassay. RESULTS: Analysis of covariance and paired Student's t tests were used for the statistical evaluation. Immediately after treatment, the perception of pain and the level of menstrual distress were significantly reduced by SMT. This reduction was associated with a significant reduction in plasma levels of KDGPF2a in the SMT group. A significant and similar reduction in plasma KDPGF2a also occurred in the sham group, indicating that a placebo effect was associated with a single sham intervention. CONCLUSIONS: This randomized pilot study suggests that SMT may be an effective and safe nonpharmacological alternative for relieving the pain and distress of primary dysmenorrhea. However, the large change in KDPGF2a observed in both treatment groups clearly indicates that further studies with more subjects, studied over a longer time frame, are needed to resolve the question of a placebo effect.  相似文献   
12.
Analysis of extant clinical records is receiving increased emphasis in nursing investigations. Appropriate use of this approach to patient research requires careful attention to data management, including assessment of reliability. Percent agreement, phi, and Kappa all serve as estimates of interrater reliability in the analysis of data. Kappa has particular merit as a measure of interrater reliability; it also has some peculiar problems in implementation and interpretation. The nature and computation of Kappa and its application in analysis of clinical data are discussed.  相似文献   
13.
Corneal pathophysiology with contact lens wear   总被引:2,自引:0,他引:2  
Contact lens wear induces a wide spectrum of changes in the appearance and function of the cornea. The most salient effect of lens wear is the hypoxically induced reduction in the rate of metabolic activity of the corneal epithelium and its sequellae. Other important alterations to corneal health associated with contact lens wear may be caused by antigenic and toxic stimuli, mechanical forces, osmotic effects and carbon dioxide retention. Perhaps the most important task facing the contact lens clinician is to distinguish between an acceptable state of physiological modification and an anomalous or pathological state of hypofunction. In this article, we review the assortment of corneal changes primarily on the basis of the causative agents and time scale with reference to the physical and chemical processes leading to the observed signs or symptoms. This procedure allows a strong foundation for understanding the etiology and management principles for the variety of effects that contact lenses may have on the cornea.  相似文献   
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Repeat hepatic resections for metastatic colorectal cancer.   总被引:7,自引:0,他引:7       下载免费PDF全文
OBJECTIVE: The authors weighed the risks and benefits of repeat liver resections for colorectal metastatic disease. METHOD: In the 6-year period between January 1985 and June 1991, 499 patients underwent liver resections for colorectal metastases at the Memorial Sloan-Kettering Cancer Center. Of these, 25 patients had repeat surgical resections for isolated recurrent disease to the liver. The clinical data for these patients were reviewed. RESULTS: The median interval between the two resections was 11 months. There were no perioperative deaths, and the complication rate was 28%. Median follow-up after the second liver resection is 19 months, with median survival of 17 months for nonsurvivors. Although the median survival after the second resection is 30 months, 20 of the 25 patients have had recurrences with a median disease-free interval of only 9 months. No characteristic of primary or metastatic disease predicted outcome, including time between presentation of the primary and development of liver metastases, disease-free interval after the first liver resection, and bilobar liver involvement. CONCLUSIONS: Although repeat liver resections can be performed safely and improves survival, the likelihood of cure from such resection therapy is low. This likelihood of further recurrences encourage studies of adjuvant or alternative treatments of this population.  相似文献   
17.
Socioeconomic status and risk for substandard medical care.   总被引:12,自引:0,他引:12  
H R Burstin  S R Lipsitz  T A Brennan 《JAMA》1992,268(17):2383-2387
OBJECTIVE--To assess whether the socioeconomic status of the patient was associated with the risk of adverse events, defined as medical injuries caused by medical management, and the proportion of these events that resulted from substandard care. SETTING--51 hospitals in New York State. METHODS--Rates of medical injury and substandard care by gender, race, income, and payer status were developed from reviews of 30,195 medical records in New York in 1984. We evaluated these socioeconomic parameters in a multivariate analysis, while controlling for hospital-level factors. RESULTS--We found that uninsured patients (odds ratio, 2.35; 95% confidence interval, 1.40 to 3.95) were at greater risk for substandard care. The characteristics of the hospitals to which patients were admitted did not affect this result. Race, gender, and income were not independently associated with risk for medical injury or substandard care in multivariate analyses. CONCLUSION--Our findings suggest that the uninsured are at greater risk for suffering medical injury due to substandard medical care.  相似文献   
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Background: Studies have consistently confirmed the benefit of liver resection for metastatic colorectal cancer. Few reports, however, have a long enough followup or sufficient 5-year survivors to study the clinical course of patients beyond 5 years.

Study Design: From July 1985 through December 1991, 456 patients underwent liver resection for colorectal metastases. Ninety-six actual 5-year survivors (21%) were identified and their clinical course retrospectively reviewed.

Results: Five-year survivors (n = 96) were more likely to have a Duke’s B primary colorectal carcinoma, fewer than four metastatic lesions, unilobar disease, and a negative histologic margin when compared with patients not surviving 5 years (n = 298). Forty-four (46%) of the 96 five-year survivors had a recurrence after hepatectomy. Of these 44, 19 (43%) were rendered disease free after further treatment. Overall, 71 of the 96 five-year survivors were free of disease at last followup. The actuarial 10-year survival of this group was 78%.

Conclusions: Patients that are disease free 5 years after liver resection are likely to have been cured by liver resection. Patients should be aggressively followed for recurrence because of the potential for further treatment and longterm survival.  相似文献   

20.
To determine the success rate and the safety of percutaneous transluminal coronary angioplasty in patients with unstable angina pectoris (group 1) versus stable angina (group 2), we studied 299 consecutive patients who underwent coronary angioplasty of 373 consecutive lesions. Of these patients, 149 had unstable angina pectoris and dilation of 188 arteries. The success rate was high and similar in both groups (95 and 93%, respectively). The groups did not differ in regard to the lesion characteristics, vessels and number of sites dilated except for an increase in the presence of thrombus in the unstable angina group (p < 0.03). Although there was a higher incidence of coronary thrombus and more acute myocardial infarction in group 1, the major complication rate did not differ from that of group 2 and was low in both of them (3 and 2%, respectively). No deaths occurred. Six patients (3 in each group) needed urgent coronary artery bypass grafting while 3 additional patients developed acute Q-wave myocardial infarction (all of them in group 1). Thus, percutaneous transluminal coronary angioplasty is a safe and successful procedure in patients with unstable angina as well as in patients with stable angina pectoris.  相似文献   
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