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91.
Ginsburg S Schreiber M Regehr G 《Advances in health sciences education : theory and practice》2004,9(2):137-145
PURPOSE: The selection process for residency positions is sometimes seen as being "opaque" and unfair by students, and can be a significant source of student stress. Yet efforts to clarify the process may not have helped reduce student stress for a number of reasons. This paper examines the nature of the knowledge that students possess and describes the implications for future efforts at addressing this knowledge. METHODS: The current study assessed the perceptions of three groups (selection committee members, faculty advisors, and students) at a single institution using two evaluation methods (ranking of a context-free list of variables, and an assessment of the legitimacy of 20 "common language" opinion statements comparing the variables). RESULTS: For the context-free ranking of variables, ICC's were moderately high for all three groups (0.479-0.584) and the disattenuated correlations were very high (0.872 to 0.946). By contrast, when more contextually relevant opinion statements were evaluated, the ICC's were much more variable (less than 0 to 0.279), the correlations (where calculable) were lower (0.449 to 0.547), and inconsistencies of opinion regarding particular variables became apparent. CONCLUSIONS: To properly understand the true nature of the opinions that are being held by the various groups it is necessary to use statements that reflect the vernacular of the "rumour mills" that are the common source of student information. 相似文献
92.
Using two luminescence-inducing cocktails, two distinct patterns of inhibition of light by different anti-oxidants have been identified, comprising Group A, in which a complete inhibition of light emission which is then followed by re-emergence of light, forming apparent S-shaped curves or similar shapes. This light pattern is induced by the “classical” anti-oxidants, ascorbate, vitamin E, uric acid, thiols, deferoxamine, as well as by anti-oxidant agents present in plasma, saliva, urine and in extracts derived from black coffee, and Group B, in which a gradually emerging “mound”-shaped pattern of light was seen with extracts from the Tibetan plant mixture PADMA-28, elderberry (Sambucol), grape seeds, green and black teas, apple, parsimony, red wines, edible oils and SOD. While the results with the Group A agents point to the presence of probably a single, major, anti-oxidants relatively sensitive to oxidation, Group B agents probably include a mixture of anti-oxidants which are more resistant to oxidation. It was also shown that agents from Group B could protect agents from Group A against consumption by the oxidants generated by the cocktails. It is proposed that these simple to use cocktails which probably generate a multiplicity of oxidants mimicking those generated by activated phagocytes, can rapidly assess the total anti-oxidant capacities (TAOC) in body fluids derived from patients suffering of excessive oxidative stress. Also, this technique may be useful in determining the content of dietary anti-oxidants recommended as supplements to enhance the resistance against excessive oxidation of lipids. 相似文献
93.
94.
Randolph JF Ginsburg KA Leach RE Blacker CM Moghissi KS Diamond MP Reame NE 《Fertility and sterility》2003,80(2):320-327
OBJECTIVE: To determine whether women with rigorously defined unexplained infertility demonstrated altered GnRH secretion, as reflected by serum LH secretion patterns. DESIGN: Prospective observational study. SETTING: National Center for Infertility Research at Michigan. PATIENT(S): Nine women with rigorously defined unexplained infertility and 11 healthy, parous age-matched control women.Gonadotropin-releasing hormone (25 ng/kg) as a bolus injection. MAIN OUTCOME MEASURE(S): Daytime pulse patterns of LH secretion measured every 10 minutes; mean serum concentrations of LH, FSH, E(2), P, PRL, and cortisol; and response to a physiologic dose of GnRH in the early follicular, late follicular, mid-luteal, and late luteal phases of the same menstrual cycle. RESULT(S): Serum LH pulse frequency and pulse amplitude and LH secretion in response to a physiologic bolus of GnRH were not significantly different in unexplained infertility patients at any phase of the cycle. Luteinizing hormone pulse frequency and amplitude, as well as response to GnRH, varied significantly across the cycle. Mean early follicular serum LH and FSH concentrations were significantly higher in unexplained infertility patients than in fertile control subjects (LH: 5.31 +/-.51 vs. 4.03 +/-.33 [mIU/mL +/- SEM]; FSH: 5.81 +/-.63 vs. 3.80 +/-.45) but were not different at any other phase of the cycle. CONCLUSION(S): These data do not support the hypothesis that unexplained infertility is caused by an abnormality in pulsatile GnRH secretion or abnormal pituitary sensitivity to GnRH. However, the results are consistent with a difference in negative feedback from the ovary to the pituitary in unexplained infertility patients that is suggestive of diminished ovarian reserve. 相似文献
95.
96.
Persellin ST Cohen MD Ginsburg WW Calamia KT Waldorf JC Khoor A 《The Journal of rheumatology》2003,30(1):191-192
Giant cell arteritis (GCA) is a disease of unknown etiology characterized by granulomatous inflammation of medium and large arteries. A 69-year-old man presented with right jaw claudication, intermittent scalp tenderness without headache, and visibly swollen temporal arteries. Results of a right temporal artery biopsy were positive for GCA. Auscultation revealed audible bruits of the temporal arteries. We believe this is the first reported example of bruits of the temporal arteries as a manifestation of GCA. The condition resolved with corticosteroid therapy. 相似文献
97.
Na(+)-Ca(2+) exchange (NCX) is crucial in the regulation of [Ca(2+)](i) and cardiac contractility, but key details of its dynamic function during the heartbeat are not known. In the present study, we assess how NCX current (I(NCX)) varies during a rabbit ventricular action potential (AP). First, we measured the steady-state voltage and [Ca(2+)](i) dependence of I(NCX) under conditions when [Ca(2+)](i) was heavily buffered. We then used this relationship to infer the submembrane [Ca(2+)](i) ([Ca(2+)](sm)) sensed by NCX during a normal AP and [Ca(2+)](i) transient (when the AP was interrupted to produce an I(NCX) tail current). The [Ca(2+)](i) dependence of I(NCX) at -90 mV allowed us to convert the peak inward I(NCX) tail currents to [Ca(2+)](sm). Peak [Ca(2+)](sm) measured via this technique was >3.2 micromol/L within < 32 ms of the AP upstroke (versus peak [Ca(2+)](i) of 1.1 micromol/L at 81 ms measured with the global Ca(2+) indicator indo-1). The voltage and [Ca(2+)](sm) dependence of I(NCX) allowed us to infer I(NCX) during the normal AP and Ca(2+) transient. The early rise in [Ca(2+)](sm) causes I(NCX) to be inward for the majority of the AP. Thus, little Ca(2+) influx via NCX is expected under physiological conditions, but this can differ among species and in pathophysiological conditions. 相似文献
98.
99.
KN?FountoulakisEmail author A?Iacovides S?Kleanthous S?Samolis K?Gougoulias I?Tsiptsios GS?Kaprinis P?Bech 《BMC psychiatry》2003,3(1):2
Background
The Major Depression Inventory (MDI) is a brief self-rating scale for the assessment of depression. It is reported to be valid because it is based on the universe of symptoms of DSM-IV and ICD-10 depression. The aim of the current preliminary study was to assess the reliability, validity and psychometric properties of the Greek translation of the MDI. 相似文献100.
In vitro fertilization for cancer patients and survivors 总被引:8,自引:0,他引:8
OBJECTIVE: To determine in vitro fertilization (IVF) outcome in cancer patients. DESIGN: Retrospective record review. SETTING: Academic, hospital-based assisted reproductive technology (ART) program. PATIENT(S): Sixty-nine women undergoing 113 IVF/gamete intrafallopian transfer (GIFT) cycles after cancer treatment in one partner, and 13 women undergoing 13 IVF cycles for embryo cryopreservation before chemotherapy/radiation. INTERVENTION(S): IVF, intracytoplasmic sperm injection (ICSI), assisted hatching, and gamete intrafallopian transfer as indicated. MAIN OUTCOME MEASURE(S): Delivery rate, spontaneous abortion rate, number of embryos cryopreserved, cancer diagnosis, systemic or local cancer treatment, female age, amount of gonadotropin used, treatment duration, peak estradiol level, and number of oocytes and embryos. RESULT(S): The women undergoing IVF after chemotherapy had poorer responses to gonadotropins than did the women with locally treated cancers even though they were younger (33.5 +/- 1.3 vs. 36.5 +/- 0.5 years; P<.05). The delivery rates after the women had undergone chemotherapy tended to be lower among the systemic treatment group than it was for the local cancer treatment group: (13.3% [2 of 15] vs. 40% [14 of 56, P=NS]). The women who had cryopreserved all embryos before chemotherapy produced more oocytes (18.7 +/- 3.2 vs. 14.5 +/- 1.2) and embryos (11.3 +/- 1.9 vs. 7.5 +/- 0.7) than did the women who had had a history of local cancer treatment. Male factor infertility as a result of cancer treatment is well treated with IVF or intracytoplasmic sperm injection, where indicated (32% delivery rate/cycle), with no difference between the frozen sperm banked before cancer treatment and fresh sperm produced after treatment. CONCLUSION(S): Chemotherapy diminishes the response to ovulation induction in assisted reproductive technologies. IVF with cryopreservation of embryos allows embryo banking before chemotherapy for women who have been newly diagnosed with cancer. Factors related to the partner affect the success of IVF for male factor infertility as a result of cancer treatment. 相似文献