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91.
From its beginnings in 1955, the American College of Nurse-Midwives has supported the concept of Quality Care Assessment and Assurance (QCAA) and charged its members with responsibility to involve themselves in such activities within their practice. Six tools are reviewed that represent a sound basis for the development of QCAA programs within nurse-midwifery practice, the ultimate goal being the provision of optimal health care to women and the childbearing family. 相似文献
92.
Iodine-131 levels in sludge and treated municipal wastewaters near a large medical complex. 下载免费PDF全文
Iodine-131 was found to dominate the gamma spectra of dried sludge and concentration liquid effluent samples from a sewage treatment plant serving the area containing the Texas Medical Center in 1975. The concentration of Iodine-131 varied considerably on a time scale of weeks but was fairly stable in the course of a single day. The partition of Iodine-131 between the dried sludge and the liquid effluent was found to be reasonably constant during the sampling period. Knowledge of the concentration in these phases and the daily output of sludge and effluent let to be estimate of an annual discharge of over one Curie of Iodine-131. Circumstantial evidence linking this discharge to the practice of nuclear medicine in the area is considered strong, but an attempt to correlate variation in the effluent activity with actual nuclide use was inconclusive due, among other reasons, to an insufficient clinical data base. An analysis of possible exposure pathway indicated that negligible human exposure resulted from the Iodine-131 released primarily because the receiving body of water is a saline industrial waterway. A more extensive analysis would be in order for a similar plant discharging treated wastewaters into an inland water system. 相似文献
93.
A significant recent advance that has occurred world over in the continuously evolving field of Magnetic Resonance Imaging (MRI) practice is the introduction of Cardiac applications. Cardiac MRI has moved to the centre stage of clinical management strategy by non-invasively imaging the structure as well as function of the heart. It has a wide range of specific applications such as delineation of morphological anatomy, quantification of flow and pressure across cardiac valve dysfunction, evaluation of myocardial function, assessment of infarcts, mapping coronary arteries and so on. Evaluation of congenital heart disease (CHD) is an important application of Cardiac MRI since the morphological details of chambers, septum, defects and anomalous connections are depicted accurately. Besides, flow information across valves, chambers, outflow tracts and shunts are also provided. This article describes our experience in the use of cardiac MRI in congenital heart disease.Key Words: Cardiac MRI, Congenital heart disease, Cyanotic and Acyanotic heart disease 相似文献
94.
JAN RIORDAN RN MN BETTY ANN COUNTRYMAN RN MN 《Journal of obstetric, gynecologic, and neonatal nursing : JOGNN / NAACOG》1980,9(6):357-361
The resources of motivation and knowledge that make the nurse a valuable support to the new mother initiating breastfeeding are needed again, equally as much, as the nurse prepares the mother for self-care at home and remains available for counseling afterwards. There are general guidelines for promoting continued breastfeeding success and for avoiding potential problems. The nurse should be familiar with these and with how to proceed in special situations and with specific breastfeeding problems. "Self-Care for Continued Breastfeeding" and "Some Breastfeeding Problems and Solutions", presented below, end the series on breastfeeding begun in the July/August issue.
The advantages of continuing breastfeeding beyond the neonatal period are reviewed and general guidelines for selfcare at home are discussed. Developmental changes in the instant and psychological and physical changes in the mother are outlined and related to breastfeeding success. Advice for working mothers and for weaning is also presented. 相似文献
The advantages of continuing breastfeeding beyond the neonatal period are reviewed and general guidelines for selfcare at home are discussed. Developmental changes in the instant and psychological and physical changes in the mother are outlined and related to breastfeeding success. Advice for working mothers and for weaning is also presented. 相似文献
95.
Light regulates sleep timing through circadian entrapment and by eliciting acute changes in behavior. These behaviors are mediated by the subcortical visual system, retinorecipient nuclei distinct from the geniculocortical system. To test the hypothesis that early visual experience shapes light regulation of behavior, the authors recorded sleep in albino rats reared in continuous dark, continuous light, or a 12-hr light-dark cycle. Dark rearing strengthened and light rearing weakened acute responses to light, including light modulation of REM sleep, a marker for pretectal function in albino rats. However, neither dark nor light rearing altered daily amounts of wakefulness, non-REM sleep, or REM sleep. Thus, light and dark rearing might differentially affect the balance between acute and circadian responses to light that, in concert, govern sleep timing. 相似文献
96.
Foote JA Kemmeter PR Prichard PA Baker RS Paauw JD Gawel JC Davis AT 《JPEN. Journal of parenteral and enteral nutrition》2004,28(3):154-157
BACKGROUND: Early postpyloric feeding is considered the accepted method of nutrition support in critically ill patients. Endoscopic and fluoroscopic techniques are associated with the highest percentage of successful placement. The purpose of this study was to compare endoscopic vs fluoroscopic placement of postpyloric feeding tubes in critically ill patients. METHODS: This is a randomized prospective clinical trial. Forty-three patients were randomized to receive feeding tubes by endoscopic or fluoroscopic technique. All procedures were performed at the bedside in the critical care unit. A soft small-bore nonweighted feeding tube was used in all cases. Successful placement was confirmed by either an abdominal x-ray for endoscopic technique or a fluoroscopic radiograph for fluoroscopic technique. RESULTS: Postpyloric feeding tubes were successfully placed in 41 of 43 patients (95%). The success rate using endoscopic technique was 96% (25 of 26), whereas the rate using fluoroscopy was 94% (16 of 17). The average time of successful placement was 15.2 +/- 2.9 (mean +/- SEM) minutes for endoscopic placement and 16.2 +/- 3.2 minutes for fluoroscopic placement, which was not statistically significant (p > .05). CONCLUSIONS: Endoscopic and fluoroscopic placement of postpyloric feeding tubes can safely and accurately be performed at the bedside in critically ill patients. Our results showed no significant difference in the success rate or time of placement between endoscopic vs fluoroscopic placement of postpyloric feeding tubes. 相似文献
97.
Our blood bank routinely screens donors for antibodies using a solid-phase red cell adherence (SPRCA) assay. Positive results are then confirmed using a tube technique with polyethylene glycol (PEG) enhancement due to reported higher specificity than with SPRCA. Over a 5-month period, 49,084 donor serum or plasma samples were tested using the SPRCA assay. Further identification of positive samples was performed using a PEG enhancement method. Testing was performed with strict adherence to the manufacturers' inserts. Of 49,084 samples, 313 (0.64%) were positive by the SPRCA assay. Of these, 99 (31.6%) samples remained positive when tested with PEG enhancement. The remaining 214 (68.4%) were negative, giving specificity for the SPRCA assay of 99.6 percent (48,985/ 49,199). We report a high specificity for antibody screening using the SPRCA assay. However, it is cost effective to perform a confirmatory tube test with PEG enhancement because 214 SPRCA assay samples were interpreted as having a negative antibody screen, thus allowing the release of valuable blood components for transfusion. 相似文献
98.
99.
In recent years evidence has accumulated for the existence of central imidazoline (I1) receptors that influence blood pressure. While there is some controversy, it has been suggested that clonidine exerts its blood pressure-lowering effect mainly by activation of imidazoline I1 receptors in the rostral ventrolateral medulla, while its sedative effect is mediated by activation of central alpha2-receptors. Moxonidine and rilmenidine are 2 imidazoline compounds with 30-fold greater specificity for I1 receptors than for alpha2-receptors. In comparison, clonidine displays a 4-fold specificity for I1 receptors compared with alpha2 receptors. Moxonidine and rilmenidine lower blood pressure by reducing peripheral resistance. They reduce circulating catecholamine levels and moxonidine reportedly reduces sympathetic nerve activity in patients with hypertension. Moxonidine and rilmenidine modestly reduce elevated blood glucose levels and moxonidine has been reported to reduce insulin resistance in hypertensive patients with raised insulin resistance. Small reductions in plasma levels of total cholesterol, low density lipoprotein-cholesterol and triglycerides have been reported with rilmenidine. Both moxonidine and rilmenidine are well absorbed after oral administration and are eliminated unchanged by the kidneys. The elimination half-life (t(1/2)) of rilmenidine and moxonidine is 8 and 2 hours, respectively, but trough/peak plasma concentration ratios indicate that moxonidine can be administered once daily, suggesting possible CNS retention. As would be expected, t(1/2) values are increased in patients with reduced renal function, and in elderly individuals. Both drugs have been compared with established antihypertensive drugs from all the major groups. Studies, almost all of which were of a double-blind, parallel-group design, indicate that blood pressure control with moxonidine or rilmenidine is similar to that with established drugs, i.e. alpha-blocking drugs, calcium antagonists, ACE inhibitors, beta-blocking drugs and diuretic agents. There have been few studies conducted solely in elderly patients. However, evidence clearly suggests that the antihypertensive effect of the imidazoline compounds is not reduced in elderly patients. The overall adverse effect profile of moxonidine and rilmenidine compares reasonably with established agents. In accord with the receptor-binding studies, drowsiness and dry mouth are observed less often with these drugs than with other centrally acting drugs, although the symptoms occur more often than with placebo. An overshoot of blood pressure was seen when treatment with clonidine, but not moxonidine, was abruptly discontinued in conscious, spontaneously hypertensive rats. Clinical evidence of withdrawal reaction with moxonidine or rilmenidine is scant but caution should be observed pending more formal studies. 相似文献
100.