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101.
Purpose. In a patient with internal derangement of the shoulder, the diagnostic method of choice is controversial. Conventional arthrography can diagnose most rotator cuff tears accurately; however, in many institutions MR arthrography is usually necessary to diagnose labral tears. We utilized decision tree methodology to compare the cost- effectiveness of conventional arthrography and conventional MRI with a hypothetical algorithm in which a patient underwent arthrography, performed with admixed gadolinium, which if negative, was followed by MRI. Design. The use of double-contrast arthrography alone, conventional MRI alone, and gadolinium-enhanced MRI used as an adjunct to conventional arthrography were modeled for the diagnosis of full-thickness rotator cuff tears (RCT), partial RCTs, labral tears, and the absence of cuff/labral tears using decision analysis methodology. English language medical publications were searched to determine the base probabilities for the accuracy of the diagnostic tests. The outcome utilities ranged from –1 to +1 to reflect the value of correct diagnostic evaluation. Charges for diagnostic tests and appropriate surgical treatments were based on 1997 Medicare reimbursement rates for professional fees and hospital charges in an outpatient setting. Sensitivity analyses were performed to evaluate the effects of uncertainty regarding the prevalence of each disease state and the accuracy of several diagnostic tests. Results. In the base-case analysis, the average effectiveness of double-contrast arthrography alone, MRI alone and arthrography selectively followed by MRI were 0.6610, 0.6715, and 0.7204, respectively. The average costs for each of these strategies were $1090, $2033, and $2339, respectively. Conclusion. Arthrography performed with admixed diluted gadolinium, which if negative is immediately followed by MRI, was somewhat more expensive than conventional MRI. However, because of much greater effectiveness, cost-effectiveness was significantly higher for our proposed algorithm. Conventional arthrography without gadolinium, although less expensive, had severely limited effectiveness. Received: 4 June 1999 Revision requested: 6 August 1999 Revision received: 30 August 1999 Accepted: 1 September 1999  相似文献   
102.
This paper describes the extent of the informal caregiving unit for older people who are physically or mentally frail living in private households or resident in long-term care institutions using cross-sectional analysis of survey data. A total of 1444 people aged 65 years or more registered with a general practitioner (GP) in four areas in England and, consenting to the study, were screened for mental or physical frailty. Of 1127 older subjects living at home 7% reported receiving no informal support, 15% had a paid supporter only and 78% nominated a key informal supporter who helped with defined activities of daily living of whom 650 (74%) were interviewed. Only 13% nominated more than one informal supporter. Key supporters were spouses (38%), daughters (30%), sons (9%), daughters-in-law (4%), other relatives (11%) and friends and neighbours (8%). Of 317 frail older people resident in long-term care institutions 175 (55%) received a main visitor at least once a week of whom 132 (75%) were interviewed. Main visitors were spouses (11%), daughters (36%), sons (23%), daughters-in-law (2%), other relatives (24%) and friends (4%). Qureshi & Walker's (1989) hierarchical, decision-making model for selecting informal caregivers was applied to the data and correctly identified 85% of key informal supporters and 79% of main visitors interviewed. This large-scale comprehensive survey of informal care for frail older people supports earlier small-scale localized studies highlighting the key role of spouses and daughters in the provision of informal support. Families of frail older people provide the support to maintain people at home.  相似文献   
103.

Purpose

We evaluated risk factors for the development of bladder tumors in spinal cord injury patients.

Materials and Methods

A retrospective review was done of all bladder tumors at 1 institution with matched controls for 7 years.

Results

We identified 17 malignant and 2 benign tumors. Indwelling bladder catheters and a history of bladder stones were statistically significant risk factors. Four patients with negative biopsies underwent repeat biopsy due to suspicious cytology and cancer was found.

Conclusions

An indwelling urinary catheter and a history of bladder stones are statistically significant risk factors. Cytology and biopsy are complementary in the evaluation of urothelial malignancy in this population. A high index of suspicion and thorough evaluation are needed in spinal cord injury patients.  相似文献   
104.
Recent developments in genetics are likely to exacerbate the ethical issues in clinical practice, especially with regard to privacy and disclosure of genetic information. To evaluate the behaviour of patients with respect to transmitting carrier information, we undertook a survey of 283 families with a balanced chromosomal rearrangement as a model. In these families, 1816 relatives were considered at risk and 806 of them were karyotyped (44.4%). The percentage of karyotypes performed is significantly related to the number of living children of the index couple, the reason for referral, the nature of the anomaly, the training of the counsellor and the age of the index case. This study shows the limits of the screening of at risk individuals within families, based on the willingness of the patients, and addresses practical and ethical issues around family disclosure in medical genetics.  相似文献   
105.
106.
A randomized prospective clinical trial was conducted to compare conventional high dose radiotherapy with hypofractionated, short course radiotherapy in poor prognosis patients with high grade glioma. The primary endpoint was overall survival.  相似文献   
107.
Wolcott-Rallison syndrome is a rare autosomal recessive condition characterized by diabetes mellitus arising in early infancy and multiple epiphyseal dysplasia. To date, nine cases have been described in the world literature. We report an affected girl who died at the age of 4 years and on whom a full autopsy was performed. In addition to neonatal diabetes mellitus and epiphyseal dysplasia, this child had mental retardation and recurrent episodes of self-limiting hepatic failure. Autopsy revealed severe pancreatic hypoplasia and markedly abnormal pancreatic histology, while histology of the bone was consistent with epiphyseal dysplasia. There was laryngeal stenosis and pulmonary hypoplasia. The heart was enlarged with mitral valve dysplasia and stenosis, left atrial dilatation, left ventricular hypertrophy, and endocardial fibroelastosis. Examination of the central nervous system showed arrhinencephaly and cerebellar cortical dysplasia. The liver showed minor histological abnormalities but no features were present to account for the recurrent hepatic failure. In addition to Wolcott-Rallison syndrome this child had a deletion at 15q11-12 in 65 of her cells.  相似文献   
108.
OBJECTIVE: In 1991 the Oregon Board of Medical Examiners initiated a separate category for the complaint of sexual misconduct. Investigated complaints of sexual misconduct brought to the Oregon Board of Medical Examiners were analyzed for the years 1991 to 1995 to serve as a baseline. Comparison was made to the Federation of State Medical Boards sexual misconduct data for 1991 and 1992.STUDY DESIGN: One hundred complaints brought against 80 licensees were evaluated by practitioner's degree, age group, sex, specialty, and disposition of complaints for the years 1991 to 1995. The allegations were classified into behavior categories of sexual impropriety, sexual transgression, and sexual violations.RESULTS: Sexual misconduct was the allegation in 5.9% of the complaints investigated for the study period. Oregon had more sexual misconduct complaints than the average reported to the Federation of State Medical Boards for the years 1991 and 1992. Most (72%) complaints came from the patients or their families. Two female physicians (2.4%) had sexual boundary complaints. Sexual misconduct complaints increased by a risk ratio of 1.44 with advancing age by decades. Allegations classified into behavior categories according to severity revealed 39% sexual impropriety, 31% sexual transgression, and 30% sexual violation. Reportable disciplinary actions occurred only with multiple allegations of sexual impropriety (6.5%) and for sexual transgression (27%) whereas sexual violation allegations often had one complainant but there were 54% reportable disciplinary actions. Family practice, obstetrics and gynecology, and psychiatry had the highest incidence of sexual misconduct complaints whereas psychiatry and obstetrics and gynecology had the highest incidence of reportable disciplinary actions. Twenty-five percent of the closed cases resulted in reportable disciplinary actions. This analysis is discussed in relationship to legal and ethical issues and the goal of zero tolerance.CONCLUSIONS: Oregon has a higher percentage of sexual misconduct complaints than the average for 42 states reporting to the Federation of State Medical Boards for the years 1991 and 1992. Analysis of the Oregon Board's experience for the study years will provide a baseline for future evaluation and as an educational resource for the Oregon Board of Medical Examiners and professional and specialty societies. Ethical standards, the reporting and investigative processes, and the legal framework are in place and lessen the incidence of sexual misconduct and work toward zero tolerance. (Am J Obstet Gynecol 1997;176:1340-8.)  相似文献   
109.
Phosphorus-31 nuclear magnetic resonance spectroscopy was used to evaluate the stability of carboxycyclophosphamide (CXCP) and carboxyifosfamide (CXIF) in human urine at pH 7.0 and 5.5 at 25°, 8°, −20°, and −80 °C. At 25 °C and pH 7.0, CXCP and CXIF are relatively stable (≈10% degradation in 24 h). In contrast, they are much less stable at pH 5.5 (≈80% degradation of CXIF and ≈50% degradation of CXCP in 24 h). The rate of degradation of CXCP and CXIF was a function of the storage temperature of the urine samples but, even at −80 °C, was not negligible: ≈30% degradation for CXCP irrespective of pH and ≈40% and 50% degradation for CXIF at pH 7.0 and 5.5, respectively, after storage for 6 months. CXCP was more stable than CXIF at either pH (7.0 or 5.5) and at all storage temperatures (8°, −20°, or −80 °C) of the urine samples. CXCP and CXIF were more stable at pH 7.0 than at pH 5.5, although this difference fell with decreasing temperatures to be almost negligible at −80 °C. To ensure a true estimate of CXCP and CXIF levels, urine samples must be frozen and stored at −80 °C within a few hours of micturition. CXCP and CXIF assays should also be carried out within 2 months and 1 month of storage, respectively. Received: 13 July 1996 / Accepted: 20 January 1997  相似文献   
110.
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