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51.
Lagares MA  Petzoldt R  Sieme H  Klug E 《Andrologia》2000,32(3):163-167
The swelling of cells in a hypo-osmotic medium has been described as an important criterion for assessing the functional integrity of the sperm plasma membrane. The resistance of equine spermatozoa to osmolarity changes was studied by extending 98 semen samples collected from nine stallions in media at five osmolarities (300, 200, 150, 100, and 50 mOsmol l(-1)). The response of the cells was measured by the spermatocrit technique and eosin staining. Spermatocrit determines the increase on spermatozoal volume under hypo-osmotic conditions, a sign of functional integrity of sperm plasma membrane, whereas the eosin staining evaluates the viability of spermatozoa. A significant positive correlation (P<0.01) was observed between spermatocrit values and percentage of eosin-unstained cells. Spermatocrit measurements and eosin staining proved to be useful methods to evaluate the integrity of sperm plasma membrane under hypo-osmotic conditions and could be used as an additional criterion to predict semen preservation ability.  相似文献   
52.
This study evaluated if the negative influence of Escherichia coli on the motility of human spermatozoa is a consequence of E. coli-induced ultrastructural alterations. Suspensions of spermatozoa were artificially infected with E. coli from a serotyped, pathogenic strain and incubated at 37 degrees C for 6 h. After incubation, spermatozoa were fixed in glutaraldehyde, stained with osmium tetroxide and ruthenium red and embedded in Spurr(R)-resin followed by ultramicrotomy. The sections were analysed subsequently by use of transmission electron microscopy. Uninfected suspensions of spermatozoa in medium and bacterial suspensions served as controls. Negative contrast technique was performed to facilitate visualization of ultrastructural details of the bacterial capsule after experimental exposure to spermatozoa. Electron microscopic evaluation revealed multiple and profound alterations in the ultrastructure of spermatozoa such as membrane defects and cytoplasmic vacuoles exclusively in spermatozoa of infected samples (> 90%). Morphological alterations involved all superficial structures of spermatozoa, in particular the plasma membrane of the mid-piece and neck as well as the inner and outer acrosomal membrane of the acrosome, indicating that morphological defects account for the immobilization of spermatozoa by E. coli. The results suggest that E. coli infection of ejaculates results in immobilization and impaired acrosomal function in human spermatozoa, findings that support the indication for antimicrobial chemotherapy in symptomatic and silent infections that affect the ejaculate.  相似文献   
53.
The concentration of chlorinated pesticides and heavy metals (lead and cadmium) was measured using gas liquid chromatography and the graphite tube atomizer of atomic absorption spectrophotometer, respectively, in semen samples collected from men in the normal human population. Significant concentrations of lead and cadmium were detected. Significant amounts of hexachlorocyclohexane (HCH) and its isomers alpha, beta, gamma and delta, the dichlorodiphenyl trichloroethane (DDT) metabolite 1,1,1-trichloro-2,2-bis (p chlorophenyl ethane) (pp'-DDE) and low values of 1,1,2-dichloro-2, 2-bis(p chlorophenyl ethane) (pp'-DDD) aldrin or endosulfan were detected. The presence of these xenobiotics in human semen might be related to the extensive use of pesticides, emission of exhaust from motor vehicles, consumption of tobacco and industrial operations.  相似文献   
54.
Objective: To compare the quality of semen in 1,055 Danish men born between 1950 and 1970 who are assumed to represent a random sample of the Danish male population of fertile age.Design: Retrospective review of data on semen quality at the time of the female partner's first IVF treatment.Setting: The Fertility Clinic, Odense University Hospital, Odense, Denmark.Patient(s): One thousand fifty-five male partners of women with tubal infertility who were referred for IVF treatment consecutively during the period 1990–1996.Intervention(s): Analysis of the semen samples delivered and used in connection with the couples' first IVF treatment.Main Outcome Measure(s): Year of birth, age at time of sample collection, sperm concentration, and semen volume.Result(s): The mean sperm concentration (±SD) was 183.7 x 106 mL and the mean semen volume (±SD) was 3.9 mL. A considerable variation in both parameters was found from year to year, but no significant change occurred in either parameter throughout the entire period. When four birth cohorts were compared, a later year of birth was not associated with any change in sperm concentration or semen volume.Conclusion(s): Sperm concentration and semen volume were not related to year of birth, indicating that sperm quality has not changed in the Danish male population during the last 20–30 years.  相似文献   
55.
人精浆酸性磷酸酶对小鼠T淋巴细胞产生IL-2的影响   总被引:2,自引:1,他引:2  
本文研究了从正常人精浆中分离纯化的酸性磷酸酶(ACP)对BALB/c小鼠脾脏细胞来源的T淋巴细胞产生IL-2的影响。本文采用MTT生物学测定法测IL-2活性。实验证明:人糖浆ACP对小鼠T淋巴细胞产生IL-2有明显的抑制作用(P<0.05),并且抑制作用随ACP剂量的增加而增强。这说明了精浆中大量ACP是构成精浆免疫抑制功能的重要组成成份之一。  相似文献   
56.
Purpose: Our purpose was to measure changes in semen quality and quantity in young healthy sperm donors in Jerusalem over time. Methods: A retrospective analysis of semen parameters over 15 years using linear regression analysis, in a single sperm bank in a tertiary university center. Study population consisted of 188 young, healthy medical students, aged 20 to 30 years, who donated sperm samples for Artificial insemination between 1980 and 1995. Results: There were no statistically significant changes in semen concentration and motility during the study period. The mean semen volume increased by 0.1 ml (5.1%) per year (P < 0.0001), with a concomitant mean rise of 5.8 × 106 (7.7%) per year in total motile sperm count. The percentage normal morphology decreased by a mean of 1.04% per year during the entire period (P < 0.0001). Conclusions: During the past 15 years, there has been an increase in total motile sperm count, secondary to an increase in semen volume, and a decline in normal morphology that are independent of the age and the duration of abstinence in fertile men.  相似文献   
57.
Purpose: Recruiting donors to a sperm bank program is difficult and slow because of high dropout rates and high rejection rates. The profile of successful and unsuccessful donors was determined at our sperm bank. Methods: A total of 199 men was screened from 1986 to 1994 in the anonymous sperm bank donor program; 174 (87%) men dropped out or did not meet minimum guidelines. The study included 25 accepted donors and 20 rejected men (of 52 rejected donors, only 20 donors who came for two consecutive semen analyses were selected). Sperm quality variables and demographic data were compared between the groups. Results: Accepted donors had significantly better semen quality in motility, velocity, linearity, and ALH than did rejected donors (P < 0.01). More rejected donors than accepted donors were single (P < 0.01). A higher percentage of accepted donors consumed caffeine (P < 0.001), and they were more likely to have college degrees (P < 0.03). Conclusions: These results indicate that loss of interest and poor semen quality were the major reasons for rejection of donors in our anonymous donor sperm bank program.  相似文献   
58.
成年男性血清生殖激素水平与精液量以及精子密度的关系   总被引:3,自引:0,他引:3  
目的:探索普通成年男性血清生殖激素水平与精液量以及精子密度的关系。方法:资料来源于对5个研究现场(河北省石家庄市、山西省太原市、贵州省贵阳市、浙江省杭州市及山东省青岛市)的普通成年男性的横断面调查。同时收集研究对象的血样和精液样本,分析黄体生成素(LH)、卵泡刺激素(FSH)、睾酮(T)以及雌二醇(E2)与精液量、精子密度之间的关系。结果:共招收研究对象978名,通过相关分析及方差分析表明,高水平T对象的精子密度较低;高水平E2对象精液量较少。Logistic回归分析发现,高水平T发生低精子密度的危险性大,低水平的LH发生低精子密度的危险性小。结论:普通成年男性血清中生殖激素水平与精液数量指标有关,但表现出的某些关联性用已知的下丘脑-垂体-睾丸轴调节机制尚无法完全解释。  相似文献   
59.
目的 考察莲子心总碱缓释片体外释放度。方法 模拟人体体内环境,用紫外分光光度法测定莲子心总碱的体外释放度。结果 莲子心总碱释药方程:log(1 0 0 -Rn) =2 . 1 1 2 - 0 . 1 2 8t(F =2 1 9 . 31 0 ,P <0 0 0 1 ) ,r =- 0 . 982 (P <0 . 0 0 1 ) ,T50 =3 . 2 33h ,Td=4 . 2 74h ,Kr=0 . 1 2 8h-1 。结论 莲子心总碱缓释片体外释药符合一级释药模式,具有缓释特点。  相似文献   
60.
高效液相色谱法测定决明子4种成分含量   总被引:1,自引:0,他引:1  
目的建立同时测定决明子中4种成分含量的高效液相色谱(HPLC)法。方法色谱柱为迪马Dimonsil柱(150 mm×4.6mm,5μm),流动相为乙腈-甲醇-0.1%磷酸溶液(49∶7∶44,V/V/V),等度洗脱,柱温为30℃,检测波长为222 nm,流速为1.0 mL/min,进样量为10μL。结果进样量线性范围橙黄决明素为0.02464~0.2464μg(r=0.99999),大黄素为0.0174~0.174μg(r=0.99999),大黄酚为0.02956~0.2956μg(r=0.99999),大黄素甲醚为0.016~0.16μg(r=0.99998);平均回收率橙黄决明素、大黄素、大黄酚、大黄素甲醚分别为99.41%,99.51%,99.48%和99.24%,RSD分别为0.58%,0.82%,0.95%和0.90%(n=6)。结论该方法可用于决明子质量的综合评价。  相似文献   
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