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91.
A variety of causative factors of infertility in male dogs has been reported. In this study, the results of clinical examination and semen evaluation of 61 infertile stud dogs are described. Infertility was defined as conception failure of at least three matings with different bitches. The dogs, belonged to various breeds, were 4–8 years old and had a history of prior normal fertility. The dogs were subjected to clinical examination including ultrasonography of the prostate and testes. The semen was evaluated using CASA and microscopically morphology and live-dead spermatozoa. In all dogs, the semen parameters were outside the reference range, and mostly oligoastheno-teratozoospermia was found. There were also three cases of azoospermia. Thirty dogs showed no clinical abnormalities of the genital organ and no signs of systemic diseases, and testicular degeneration was assumed as the possible cause of infertility. In 20 dogs, BPH was diagnosed. In three dogs, infertility was associated with hypothyroidism. Three dogs had a history of babesiosis, and one dog prolonged ketoconazole treatment. One case each of chronic prostatitis, prostatic adenocarcinoma, epididymitis and retrograde ejaculation was diagnosed. The cause of acquired infertility could not be identified in almost half of the dogs. In other, infertility was often associated with prostate diseases.  相似文献   
92.
The aim of the randomised trial was to compare conventional semen parameters, sperm DNA fragmentation levels and satisfaction levels between semen samples collected at home and at the clinic. We recruited 110 men with a history of infertility for at least 1 year from the outpatient andrology clinic. Each man collected two semen samples, one at home and one at the clinic. Men were randomly assigned into the home first (n = 55) or clinic first (n = 55) groups. The primary outcome was sperm concentration. There was no significant difference in sperm concentration, sperm DNA fragmentation levels or other conventional semen parameters between home first and clinic first samples (> .05), while satisfaction levels were significantly higher for home first samples (p < .01). Consistent results were obtained when comparing home-collected and clinic-collected samples within individuals. Men can be offered the option to collect semen samples at home for examination or assisted reproduction without compromising semen quality, especially for those with difficulty in producing semen samples at the clinic.  相似文献   
93.
Cassiae semen has been shown to play significant roles in reversing “liver fire” to improve vision. The systems mechanism of Cassiae semen for hepatoprotection and brightening eyes has not been fully explored. The systems pharmacology approach is proposed to dissect the potential pharmacological mechanism of Cassiae semen for hepatoprotection and brightening eyes. The results showed that 26 active components of Cassiae semen that connected with 230 targets were obtained. Gene ontology enrichment, network and pathway analysis explored that Cassiae semen is responsible for hepatoprotection and brightening eyes. The current study will contribute to the research and development of functional foods.  相似文献   
94.
The effects of freezing technique and thawing protocol on thawed semen viability and fertility were studied. Ejaculates from 5 stallions (= 25) were frozen by conventional or a fast‐freezing technique. Frozen semen was thawed by two thawing protocols (37 °C 30 s?1 or 75 °C 7 s?1). Thawed semen was evaluated by progressive motility, vigour, morphology and plasma membrane integrity. Mares (= 25) were inseminated with 300 (= 11) or 150 (= 14) million spermatozoa. A greater (P < 0.05) vigour and progressively motile spermatozoa were detected, respectively, at thawing and after 20 min post‐thawing in the fast‐freezing technique than in the conventional one. Plasma membrane integrity was also greater (P < 0.05) in semen frozen with the fast‐freezing technique. Semen viability was not affected by thawing protocol. Pregnancy rate using the fast‐freezing technique was 76% (19/25), and did not differ (P > 0.05) between insemination doses. We concluded that the 150 million progressively motile spermatozoa per dose using a deep‐horn insemination maximises the use of equine semen. The fast‐freezing technique, as compared to the conventional one, efficiently preserves the viability and fertilising capacity of spermatozoa, indicating a new method to improve the fertility of frozen equine semen.  相似文献   
95.
This study aimed to characterise canine flow cytometry semen analysis, as well as seminal reactive oxygen species dosage using the Golden Retriever breed as model of study. Moreover, we searched for the influence of muscular dystrophy in Golden Retriever dogs on semen parameters. Thirty‐seven semen samples were obtained from healthy Golden Retrievers (n = 15) and from muscular dystrophy affected dogs (n = 22). Sperm‐rich fractions were analysed by standardised breeding soundness examination in addition to the assay of fluorescence assisted cell sorting for acrosome integrity, mitochondrial activity and DNA fragmentation. Volume of ejaculate, per cent of motile spermatozoa and vigour were similar between groups; there were no differences in the per cent of minor and major defects. Integrity of acrosomal membrane, mitochondrial potential and sperm DNA fragmentation had no significant differences between groups either. Animals from control group had higher concentration of spontaneous seminal oxidative species in comparison with affected animals. Dogs affected by dystrophy had seminal parameters similar to those observed in healthy dogs except for the lower concentration of oxidative species. Future studies aiming to establish reference values for canine seminal parameters should be considered preferably with distinction of breeds.  相似文献   
96.
Zika virus (ZIKV) RNA has been found to remain in human semen for up to one year after infection, but the presence of Flavivirus antigens in the different compartments of semen has been largely unexplored. Following the introduction of ZIKV in Nicaragua (2016), a prospective study of patients with clinical symptoms consistent with ZIKV was conducted in León to investigate virus shedding in different fluids. ZIKV infection was confirmed in 16 male subjects (≥18 years of age) by RT-qPCR in either blood, saliva or urine. Of these, three provided semen samples at 7, 14, 21, 28, 60 and 180 days postsymptom onset (DPSO) for Flavivirus antigens and RNA studies. These cases were compared with 19 asymptomatic controls. Flavivirus antigens were examined by immunofluorescence (IF) using the 4G2 Mabs, and confocal microscopy was used to explore fluorescence patterns. The three (100%) symptomatic subjects and 3 (16%) of the 19 asymptomatic subjects had Flavivirus antigens and viral RNA in the spermatozoa fraction. The percentage of IF Flavivirus-positive spermatozoa cells ranged from 1.9% to 25% in specimens from symptomatic subjects, as compared with 0.8% to 3.8% in specimens from asymptomatic controls. A marked IF-pattern in the cytoplasmic droplets and tail of the spermatozoa was observed. The sperm concentrations (45 × 106/mL vs. 63.5 × 106/mL, p = 0.041) and the total motility percentage (54% vs. 75%, p = 0.009) were significantly lower in specimens from ZIKV-positive than in those of ZIKV-negative. In conclusion, this study demonstrated the presence of Flavivirus antigens and RNA within a time frame of 28 DPSO in sperm cells of symptomatic and asymptomatic subjects during the ZIKV epidemic. These findings have implications for public health, in terms of nonarthropod-born, silent transmission facilitated by sperm cells and potential transmission from asymptomatic males to pregnant women, with consequences to the fetus.  相似文献   
97.
98.
99.
We investigated whether the hypo-osmotic swelling (HOS) test is a reliable screening method for routine semen specimen quality screening. Of 159 male patients, 171 semen samples were investigated using the HOS test as well as routine semen specimen screening used in our clinic. There was a significant correlation between the HOS test and most semen parameters. There was no significant correlation between the HOS test and the percentage of morphologically normal spermatozoa in the initial semen sample. The HOS test is a reliable screening method for routine semen quality screening. © 1996 Wiley-Liss, Inc.  相似文献   
100.
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