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11.
BACKGROUND: The growth pattern of the smallest ovarian follicles in humans is still incompletely documented. Using follicle hemispheres in thick histological sections, morphometric changes of primordial to primary follicles and possible age-related effects were evaluated. METHODS: In ovarian sections from 25 females aged 4-39 years a total of 1122 primordial, transitory or primary follicles were assessed for the diameters of follicles, oocytes and oocyte nuclei and for number of granulosa cells (GCs). RESULTS: The number of GCs in primordial, transitory and primary follicles were approximately 30, 50 and 100, respectively. The diameters of primordial follicles and oocytes increased with the woman's age until the mid-30's, after which time they decreased in size. The number of GCs in primordial follicles showed a moderate increase with age, whereas the number of GCs in transitory follicles showed a clear increase with age . The oocyte nucleus diameter (14-23 microm) showed significant linear correlations with the oocyte and follicular diameters and number of GCs in the follicle, while the number of GCs in the whole follicle and in the largest cross-section were closely related to the oocyte diameter. CONCLUSIONS: The number of GCs in small follicles is accurately estimated and shows an increase with age, indicating that the starting point of follicular development alters with female age. The age-related changes observed may be linked to the poorer reproductive performance of older women.  相似文献   
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13.
The purpose of this study was to investigate the effects of blockade of the saphenous nerve and the posterior branch of the obturator nerve in addition to a standard analgesic regimen for patients discharged the same day after knee arthroscopy. The primary outcome was knee pain on flexion during the first 24 postoperative hours, calculated as area under the curve. We allocated 60 patients to ultrasound‐guided nerve blocks with either ropivacaine or saline, 30 to each. The median (IQR [range]) pain score on knee flexion in the ropivacaine group 2.0 (1.1–3.7 [0.1–7.1]) was not statistically different to that in the saline group (3.3 (1.7–4.6 [0.3–6.8]), p = 0.06). There were no differences in pain at rest, opioid consumption or function.  相似文献   
14.
There are several reports of familial testicular cancer in the literature but few systematic attempts have been made to estimate the risk of testicular cancer in first-degree relatives of patients with this neoplasm, and the risk remains to be fully assessed in population-based studies. By means of data from the Danish Cancer Registry, we identified all testicular cancer patients (index cases) born and diagnosed during 1950–1993 in Denmark. Their fathers were identified from national registries, as were the brothers of a subcohort of these patients. Familial cancer occurrence was determined through linkage with the cancer registry and compared with the cancer incidence in the general male population in Denmark. The ratio of observed to expected cancers generated the measure used for the relative risk. Fathers of 2,113 index cases with testicular cancer experienced an almost 2-fold risk of developing testicular cancer themselves (RR = 1.96; 95% CI: 1.01–3.43). Overall, the fathers had a decreased relative cancer risk (RR = 0.84; 95% CI: 0.74–0.95) with a significantly decreased risk of cancers of the lung and digestive organs. Brothers of a subcohort of 702 index cases showed a markedly increased risk of testicular cancer (RR = 12.3; 95% CI: 3.37ndash;31.5). In conclusion, we documented a significantly increased familial risk of testicular cancer which was relatively more pronounced between brothers than between fathers and sons. These findings support the possible involvement of a genetic component in the aetiology of testicular cancer, but also leave room for a hypothesized influence of in-utero exposures, such as specific maternal hormone levels, that might be shared by brothers. © 1996 Wiley-Liss, Inc.  相似文献   
15.
Monospecific antisera against two fetal antigens (FA-1 and FA-2), alphafetoprotein (AFP) and two endometrial proteins (PP12 and PP14) were used to examine the distribution of these proteins and antigens in human trophoblast and gestational endometrium in first and third trimesters of pregnancy, normal human ovary and fetal tissues by indirect immunoperoxidase histochemical localisation techniques.

Fetal liver stained exclusively for FA-1 and AFP which was used as a reference protein. Staining for FA-2 was seen in fetal connective tissue, in particular the basement membrane. FA-1 and FA-2 did not stain positively in decidua, trophoblast or ovarian tissue. Gestational endometrium stained positively for PP14 exclusively in the glandular epithelium, whilst staining for PP12 was seen only in the stromal cells. Trophoblast, both early and late, and ovarian tissue did not stain positively for any of the four substances tested.  相似文献   

16.
Topoisomerase II is the primary cellular target for a variety of antineoplastic drugs that are active against human cancers. These drugs exert their cytotoxic effects by stabilizing covalent topoisomerase II-cleaved DNA complexes that are fleeting intermediates in the catalytic cycle of the enzyme. Despite this common feature of drug action, a number of mechanistic differences between drug classes have been described. These mechanistic differences (including effects on DNA cleavage/religation, DNA strand passage, and adenosine triphosphate hydrolysis) were used as the basis for a series of competition experiments to determine whether different compounds share a common site of action on topoisomerase II or interact at distinct sites. Results of the present study strongly suggest that at least four structurally disparate antineoplastic drugs, etoposide, amsacrine, genistein, and the quinolone CP-115,953, share an overlapping interaction domain on the enzyme.Paper presented at the Topoisomerase Inhibitors Conference, University of Maryland Cancer Center, 27–30 October 1993, Monterey, California, USA. Supported in part by Bristol Myers Oncology Division  相似文献   
17.
Maternal circulating pregnancy-associated plasma protein A (PAPP-A) was measured in 51 patients with vaginal bleeding in the first half of pregnancy. Concentrations of PAPP-A were consistently lower in pregnancies which failed. In the prediction of early pregnancy failure, the predictive value of depressed maternal PAPP-A levels was 58%, the sensitivity was 91.9%, and specificity was 95.1%. These results compared favorably with other biochemical tests of placental function. However, if fetal life was demonstrated ultrasonically, depressed levels of PAPP-A substantially differentiated between those pregnancies which continued normally and those which did not, suggesting that PAPP-A estimations would be of clinical value in cases previously beyond the reach of any diagnostic measure.  相似文献   
18.
In the present study we examined the relationship among handedness, immune functioning, and behavioural reactivity in rhesus macaques. We used the absolute number of CD4+ (T-helper) and CD8+ (T-suppressor) cells as dependent measures of immune functioning. We derived reactivity profiles from behavioural responses to a threat, and hand preference profiles from a quadrupedal food-reaching test. The results indicate positive correlations between the frequency of right versus left hand reaches and the absolute number of CD4+ cells, and between the frequency of right versus left hand reaches and the degree of human-directed aggression in response to an invasive threat. Immune measures were not associated with the strength of hand preference. These results are consistent with and extend previous findings obtained with rodents to nonhuman primates and provide further support for the view that behavioural lateralisation is associated with immune functioning and behavioural reactivity.  相似文献   
19.
Short bowel syndrome is an uncommon disease that results from extensive intestinal resection. Short bowel patients develop severe malabsorption of macronutrients, micronutrients, electrolytes and water, and pose difficult management problems. This report describes a typical patient with the short bowel syndrome and how each component of the malabsorption syndrome is managed to maintain nutritional, electrolyte, and water balance. In practice, some short bowel patients become dependent on parenteral nutrition for life, while others become independent with time due to intestinal adaptation and can be managed on oral intake and supplementations. Short bowel patients are at risk of developing gallstones, oxalate kidney stones and, rarely, d-lactic acidosis, and the pathophysiology of these disease processes is outlined. A minority of short bowel patients may ultimately require intestinal transplantation due to irreversible complications, and the current status of this intervention is reviewed. Finally, growth factors that stimulate intestinal growth and, thus, enhance absorptive capacity, are currently being identified and may eventually be introduced in the treatment of these patients.  相似文献   
20.
SUBJECT: Data from the compulsory Danish National IVF Registry from 1994 and 1995 regarding treatments, abortions and complications following assisted reproductive technologies. METHODS: Data were generated through registries and compared to pregnancies in Denmark in 1995. Those pregnancies that resulted in a delivery were compared to a matched control group. RESULTS: In 1994 and 1995 5219 women were treated in 9471 initiated cycles. The numbers increased over the period. The overall delivery rate per initiated cycle was 19%, egg donation 24%, IVF 20%, ICSI 16% and frozen egg replacement 10%. The rates increased over the period. The rate of spontaneous abortions was highest for ICSI (25%) and egg donation (27%). For IVF and ICSI the birth rates per transfer of 1 embryo was 13, 1%, 2 embryos 25, 4%, 3 embryos 25, 8% and 4 or more 3, 8%. Transfer of 2 embryos resulted in 75% singleton, 25% twin and 0.2% triplet deliveries. After transfer of 3 embryos the corresponding rates were 68%, 29% and 4%. No quadruplet deliveries occurred. Totally, 1.4% reported complications to the treatment, the most frequent being ovarian hyperstimulation syndrome. In the study group 5.8% of the women who gave birth were diagnosed with imminent abortion vs. 3.0% in the control group (OR 1.98, CI 1.41-2.78). CONCLUSIONS: Transfer of three embryos did not result in higher pregnancy rates as compared to transfer of two embryos. The first data from the Danish IVF Registry support data from other registries regarding treatment, pregnancy outcome and complications during pregnancy.  相似文献   
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