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101.
D D Karp L M Parker N Binder R Tantravahi B R Smith T J Ervin G P Canellos 《American journal of hematology》1985,18(3):243-249
Seven nonsplenectomized patients with blastic CGL have received high dose BCNU chemotherapy followed by cryopreserved peripheral blood stem cells (PBSC). The PBSC obtained at diagnosis were stored in the vapor phase of liquid nitrogen in 10% dimethyl sulfoxide for 11-46 months prior to use. Patients received 2.9 X 10(8) (1.9-7.8) thawed washed mononuclear cells/kg over 30 minutes with minimal morbidity. One patient was not rendered pancytopenic and died with blastic leukemia at 4 months. One patient, previously treated with daily busulfan, died of progressive hepatic failure 2 months after high dose BCNU. Restoration of the chronic phase of CGL was observed in the remaining five patients. Peripheral blood counts returned to normal ranges after a median of 19 days. Median survival for all patients is 11 months. Cytogenetic studies revealed elimination of acquired aneuploid cell lines in four of seven patients with persistence of Ph1. We conclude that: 1) frozen PBSC retain their viability for up to 4 years after cryopreservation and 2) the use of autologous PBSC following ablative chemotherapy may be associated with both symptomatic and karyotypic improvement in patients with blastic CGL. 相似文献
102.
F M Guttman L T Nguyen J M Laberge N V Nguyen T A Seemayer L Gibbons 《Journal of pediatric surgery》1985,20(6):747-753
Successful preservation of small bowel by cryobiologic techniques would increase the feasibility of intestinal transplants. Immunosuppression by Cyclosporin A (CyA) has also increased interest in intestinal transplantation. We have investigated the effect of cryopreservation and immunosuppression in fetal rat intestinal transplantation. Segments of fetal bowel implanted isogeneically into the paravertebral gutter of young rats were found to grow in a high percentage of animals (53% to 100%). Segments frozen to -20 degrees C or -40 degrees C at two rates of cooling, grew isogeneically (50% to 89%), demonstrating the feasibility of cryopreservation. Histologic examination of this bowel showed preservation of structure. When these segments were cooled and implanted allogeneically, no immunosuppressive effect was found. Segments protected by daily CyA administration grew. No synergistic effect was seen by associating CyA and cryopreservation. These experiments suggest the possibility of creating fetal small bowel long-term banking. 相似文献
103.
D.?V.?Gol’dshtein E.?I.?Smol’yaninova A.?G.?PogorelovEmail author 《Bulletin of experimental biology and medicine》2004,138(7):40-41
The need for effective methods of cryopreservation of early mammalian embryos necessitates the study of the mechanisms of
blastomere adaptation to the equilibration procedure and subsequent washing from the cryoprotector. The osmotic effects during
these procedures can cause electrolyte imbalance in embryonic cells. Intracellular potassium concentrations at the stage of
two-blastomere mouse embryo were studied by electron probe microanalysis.
Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 138, No. 7, pp. 48–49, July, 2004 相似文献
104.
OBJECTIVE: To compare the outcomes of first-attempt IVF-intracytoplasmic sperm injection (ICSI) cycles when using fresh testicular biopsy samples vs. frozen biopsy samples. DESIGN: Retrospective chart review of 92 consecutive first-attempt IVF-ICSI cycles. SETTING: Two IVF programs. PATIENT(S): Forty consecutive first-attempt IVF-ICSI patients using sperm from fresh testicular biopsy samples and 52 consecutive first-attempt IVF-ICSI cycles using frozen testicular biopsy samples. INTERVENTION(S): Testicular biopsy, IVF-ICSI with fresh and frozen-thawed spermatozoa. MAIN OUTCOME MEASURE(S): Fertilization rates, embryo quality, pregnancy, delivery, and spontaneous abortion rates. RESULT(S): A significantly increased ICSI fertilization percentage was obtained with frozen testicular biopsy samples (76.5% +/- 3.1%) vs. fresh biopsy samples (68.3% +/- 2.6%). However, embryo quality, pregnancy, and delivery rates were higher in the fresh biopsy group. Mean embryo score was 4.54 +/- 0.31 and 3.62 +/- 0.2 in the fresh vs. frozen group, respectively. Chemical pregnancy rates (60% vs. 49.1%), clinical pregnancy rates (56.4% vs. 41.2%), and delivery rates (48.7% vs. 31.2%) were each higher in the fresh group vs. frozen group. Accordingly, the spontaneous abortion rate was lower in the fresh group (21.7%) vs. the frozen group (33.3%). CONCLUSION(S): Although the use of frozen biopsy samples has logistical advantages, we conclude it may be advantageous to use fresh testicular biopsy samples in IVF-ICSI cases whenever possible, as fresh specimens yielded significantly improved embryo quality, generally higher pregnancy rates, and lower spontaneous abortion rates. 相似文献
105.
Agarwal A Ranganathan P Kattal N Pasqualotto F Hallak J Khayal S Mascha E 《Fertility and sterility》2004,81(2):342-348
OBJECTIVE: To examine the outcome of assisted reproduction techniques (ART) using cryopreserved semen from patients with cancer. DESIGN: Prospective. SETTING: Therapeutic semen banking program at a tertiary healthcare center. PATIENT(S): Twenty-nine men with cancer who cryopreserved their sperm before treatment at our facility from 1982 to 2001 and withdrew their samples for assisted reproduction (IUI, IVF, or intracytoplasmic sperm injection [ICSI]). INTERVENTION(S): Sperm bank records were used to identify the patients. Information on fertility potential indices was obtained from medical records and through interviews. Of the 29 patients, 9 had testicular cancer, 12 had Hodgkin's disease, and 8 had other types of cancer. MAIN OUTCOME MEASURE(S): Pregnancy and live births. RESULT(S): A total of 87 ART cycles (42 IUI, 26 IVF, and 19 ICSI) was performed. Of those cycles, 18.3% resulted in pregnancy (7% IUI, 23% IVF, and 37% ICSI), and 75% of the pregnancies resulted in a live birth (100% IUI, 83% IVF, and 57% ICSI). There was no significant difference in the outcomes when the results were stratified by type of ART and malignancy. None of the 11 infants who were born had congenital anomalies. CONCLUSION(S): Our findings emphasize the need for physicians to discuss the issue of semen cryopreservation with all men of reproductive age who have cancer before antineoplastic therapy is started. 相似文献
106.
Quantitative assessment of ischemic tissue damage in ovarian cortical tissue with or without antioxidant (ascorbic acid) treatment 总被引:11,自引:0,他引:11
OBJECTIVE: To estimate ischemic tissue damage in ovarian cortex and to evaluate the effectiveness of ascorbic acid, an antioxidant, to protect ovarian tissue from apoptosis caused by ischemia. DESIGN: In vitro laboratory experiments. SETTING: Academic research institute. INTERVENTION(S): Fresh and frozen/thawed cortical sections of bovine ovaries were incubated in MEM medium with or without ascorbic acid for a duration of 3, 24, and 48 hours at 37 degrees C. MAIN OUTCOME MEASURE(S): Oxygen consumption rates, lactate dehydrogenase concentrations, apoptosis rates determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining, and DNA fragmentation analysis. RESULT(S): The oxygen consumption rates were correlated inversely with the duration of incubation. When the rates of apoptosis in primordial follicles with or without ascorbic acid treatment were compared, there was no statistically significant difference between the two groups. However, the ascorbic acid treatment group showed significantly decreased apoptosis in ovarian cortex (stromal cells) with 24 hours of incubation. CONCLUSION(S): The correlation between ischemic tissue damage and the duration of ischemia was verified. Ovarian cortex could tolerate ischemia at least for 3 hours. Ascorbic acid treatment reduced apoptosis in ovarian cortex up to 24 hours of incubation in vitro. It appeared that stromal cells were more vulnerable to ischemia compared to primordial follicles. 相似文献
107.
OBJECTIVE: To investigate Volvox globator as an easy-to-handle vehicle and as a safe alternative for cryopreservation of functional motile sperm cells. DESIGN: Prospective, controlled, clinical pilot study. SETTING: Two in vitro fertilization (IVF) outpatient clinics for reproductive medicine. PATIENT(S): Fifteen patients with severe male infertility (density <100 motile sperm per milliliter) who were recruited from two IVF programs. The sperm cells were not intended for clinical use after thawing. INTERVENTION(S): In each case, a predetermined number (n = 8) of motile and morphologically intact sperm cells were injected into each Volvox sphere and then cryopreserved. The quality of the sperm cells and the handling of the Volvox spheres were verified. MAIN OUTCOME MEASURE(S): Postthaw recovery rate in cases of severe male infertility and the amount of motile sperm after thawing. RESULT(S): The postthaw recovery rate was 100%. At least 60% of the sperm cells were motile after thawing. CONCLUSION(S): The use of the spherical algae Volvox globator offers a promising, inexpensive, and easy approach to the cryopreservation of functional motile sperm cells. Volvox globator is an alternative in countries that prohibit the destructive use of oocytes, even after fertilization has failed. 相似文献
108.
OBJECTIVE: To evaluate the ability of two cryopreservation methods and three cryoprotectants to preserve sperm quality. DESIGN: A prospective clinical study. SETTING: Male infertility clinic at a tertiary healthcare center. PATIENT(S): Twenty infertile men and 10 healthy donors. INTERVENTION(S): In the first experiment, semen was cryopreserved by either the Irvine Scientific method (IS) or the Cleveland Clinic Foundation (CCF) method. In the second experiment, semen was cryopreserved by the IS method and one of three cryoprotectants: TES and Tris yolk buffer, Sperm Freezing Medium, or Enhance Sperm Freeze. MAIN OUTCOME MEASURE(S): Postthaw sperm motility, cryosurvival, and kinematics. RESULT(S): Percentages of postthaw sperm motility and cryosurvival were higher in the IS cryopreservation method compared with in the CCF method (15.94 +/- 9.19 vs. 12.07 +/- 7.31 and 47.42 +/- 17.44 vs. 35.76 +/- 17.56). However, the CCF method resulted in significantly better sperm kinematics. Postthaw motility in the donors and patients was highest in the samples frozen in TES and Tris yolk buffer medium. CONCLUSION(S): The IS method was associated with more flash freezing compared with the CCF method and resulted in better preservation of sperm motility and a higher cryosurvival rate. TES and Tris yolk buffer was most effective at protecting sperm from the negative effects of the cryopreservation process. This may be due to the presence of egg yolk along with glycerol. 相似文献
109.
Evaluation of chromatin integrity in human sperm using acridine orange staining with different fixatives and after cryopreservation 总被引:3,自引:0,他引:3
Staining of cells with acridine orange (AO) has been widely accepted as a predictor of DNA damage in many cell types. Because of variability of protocols used in previous studies, the AO staining technique has not been widely accepted as a screening test to predict DNA damage in human sperm. In order to further validate the use of AO staining, sperm were evaluated using numerous variations in the staining protocol. This study also elucidated the effects of cryopreservation on sperm DNA. Sperm fixation in Carnoy's solution showed significantly (P < 0.05) more DNA damage (29.9 +/- 4.5%) than 2% glutaraldehyde (14.4 +/- 2.1%), 4% paraformaldehyde (5.5 +/- 1.7%), no fixation (15.8 +/- 4.3%) but did not differ from Diff Quik solution (19.2 +/- 5.8%). No difference was observed for sperm DNA damage assessment using a 0.2 m (15.5 +/- 3.2%) or 0.3 m (14.9 +/- 3.3%) concentration of Na(2)HPO(4).7H(2)O in the AO staining solution. Frozen-thawed semen samples showed increased damage to sperm DNA under both Carnoy's (fresh: 10.9 +/- 1.3%; frozen: 30.8 +/- 2.9%; P < 0.05) and Diff Quik fixation (fresh: 6.2 +/- 0.8; frozen: 17.1 +/- 2.5%P < 0.05). Present data also showed that spermatozoa from some individuals are more prone to DNA damage after freezing and thawing procedures than others. In conclusion, Carnoy's fixative provides a better predictive value for DNA damage to sperm using AO staining. Additionally, cryopreservation increased damage to the sperm DNA. 相似文献
110.
The advice that should be given to a couple considering assisted reproductive technologies for the treatment of their infertility, when they are completely opposed to the destruction of surplus embryos, is discussed. It is urged that they do not use treatments that generate surplus embryos. They should be given the options of declining IVF and considering adoption, or less efficient treatments, namely limited ovarian stimulation, limited insemination of available ova or natural cycle IVF where no surplus embryos are generated. 相似文献